diff --git a/.github/workflows/build_wheels_linux.yml b/.github/workflows/build_wheels_linux.yml
index 7ff34a18..5315e161 100644
--- a/.github/workflows/build_wheels_linux.yml
+++ b/.github/workflows/build_wheels_linux.yml
@@ -4,6 +4,7 @@ on:
   pull_request:
     branches:
       - master
+      - 3.4
     paths-ignore:
       - '.github/workflows/build_wheels_linux_arm.yml'
       - '.github/workflows/build_wheels_windows*'
@@ -23,7 +24,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest]
-        python-version: ['3.6', '3.7', '3.8', '3.9', '3.10']
+        python-version: ['3.6']
         platform: [x64]
         with_contrib: [0, 1]
         without_gui: [0, 1]
@@ -37,13 +38,12 @@ jobs:
       MB_PYTHON_VERSION: ${{ matrix.python-version }}
       TRAVIS_PYTHON_VERSION: ${{ matrix.python-version }}
       MB_ML_VER: 2014
-      NP_TEST_DEP: numpy==1.19.4
-      NP_TEST_DEP_LATEST: numpy==1.21.2
       TRAVIS_BUILD_DIR: ${{ github.workspace }}
       CONFIG_PATH: travis_config.sh
-      DOCKER_IMAGE: quay.io/asenyaev/manylinux2014_${PLAT}
+      DOCKER_IMAGE: quay.io/opencv-ci/opencv-python-manylinux2014:${PLAT}
       USE_CCACHE: 1
       UNICODE_WIDTH: 32
+      PLAT: x86_64
       SDIST: ${{ matrix.build_sdist || 0 }}
       ENABLE_HEADLESS: ${{ matrix.without_gui }}
       ENABLE_CONTRIB: ${{ matrix.with_contrib }}
@@ -59,25 +59,64 @@ jobs:
       if: github.event_name == 'pull_request'
       run: git submodule update --remote
 
-    - name: Setup Environment variables
-      run: |
-        if [ "schedule" == "${{ github.event_name }}" ]; then echo "TRAVIS_EVENT_TYPE=cron" >> $GITHUB_ENV; else echo "TRAVIS_EVENT_TYPE=${{ github.event_name }}" >> $GITHUB_ENV; fi
-        if [ "schedule" == "${{ github.event_name }}" ]; then echo "BUILD_COMMIT=master" >> $GITHUB_ENV; else echo "BUILD_COMMIT=$BUILD_COMMIT" >> $GITHUB_ENV; fi
-        if [ "x64" == "${{ matrix.platform }}" ]; then echo "PLAT=x86_64" >> $GITHUB_ENV; fi
-        if [ "3.10" == "${{ matrix.python-version }}" ]; then echo "TEST_DEPENDS=$(echo $NP_TEST_DEP_LATEST)" >> $GITHUB_ENV; else echo "TEST_DEPENDS=$(echo $NP_TEST_DEP)" >> $GITHUB_ENV; fi
-
-    - name: build
+    - name: Build a package
       run: source scripts/build.sh
 
-    - name: install and test
-      run: source scripts/install.sh
-
-    - name: saving artifacts
+    - name: Saving all wheels
       uses: actions/upload-artifact@v2
       with:
         name: wheels
         path: wheelhouse/opencv*.whl
 
+    - name: Saving a wheel accordingly to matrix
+      uses: actions/upload-artifact@v2
+      with:
+        name: wheel-${{ matrix.with_contrib }}-${{ matrix.without_gui }}-${{ matrix.build_sdist }}
+        path: wheelhouse/opencv*.whl
+
+  test:
+    needs: [build]
+    runs-on: ${{ matrix.os }}
+    defaults:
+      run:
+        shell: bash
+
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest]
+        python-version: ['3.6', '3.7', '3.8', '3.9', '3.10']
+        platform: [x64]
+        with_contrib: [0, 1]
+        without_gui: [0, 1]
+        build_sdist: [0]
+
+    env:
+      ACTIONS_ALLOW_UNSECURE_COMMANDS: true
+      MB_PYTHON_VERSION: ${{ matrix.python-version }}
+      NP_TEST_DEP: numpy==1.19.4
+      NP_TEST_DEP_LATEST: numpy==1.21.2
+      CONFIG_PATH: travis_config.sh
+      PLAT: x86_64
+
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v2
+      with:
+        submodules: true
+        fetch-depth: 0
+
+    - name: Setup Environment variables
+      run: if [ "3.10" == "${{ matrix.python-version }}" ]; then echo "TEST_DEPENDS=$(echo $NP_TEST_DEP_LATEST)" >> $GITHUB_ENV; else echo "TEST_DEPENDS=$(echo $NP_TEST_DEP)" >> $GITHUB_ENV; fi
+
+    - name: Download a wheel accordingly to matrix
+      uses: actions/download-artifact@v2
+      with:
+        name: wheel-${{ matrix.with_contrib }}-${{ matrix.without_gui }}-${{ matrix.build_sdist }}
+        path: wheelhouse/
+
+    - name: Package installation and run tests
+      run: source scripts/install.sh
 
   build_sdist:
     runs-on: ${{ matrix.os }}
@@ -107,7 +146,7 @@ jobs:
       NP_TEST_DEP: numpy==1.19.4
       TRAVIS_BUILD_DIR: ${{ github.workspace }}
       CONFIG_PATH: travis_config.sh
-      DOCKER_IMAGE: quay.io/asenyaev/manylinux2014_${PLAT}
+      DOCKER_IMAGE: quay.io/opencv-ci/opencv-python-manylinux2014:${PLAT}
       USE_CCACHE: 1
       UNICODE_WIDTH: 32
       SDIST: ${{ matrix.build_sdist || 0 }}
@@ -131,19 +170,14 @@ jobs:
         python-version: ${{ matrix.python-version }}
         architecture: ${{ matrix.platform }}
 
-    - name: Setup Environment variables
-      run: |
-        if [ "schedule" == "${{ github.event_name }}" ]; then echo "TRAVIS_EVENT_TYPE=cron" >> $GITHUB_ENV; else echo "TRAVIS_EVENT_TYPE=${{ github.event_name }}" >> $GITHUB_ENV; fi
-        if [ "schedule" == "${{ github.event_name }}" ]; then echo "BUILD_COMMIT=master" >> $GITHUB_ENV; else echo "BUILD_COMMIT=$BUILD_COMMIT" >> $GITHUB_ENV; fi
-
-    - name: before install
+    - name: Build a package
       run: |
         set -e
         # Build and package
         set -x
           python -m pip install --upgrade pip
           python -m pip install scikit-build
-          python setup.py sdist
+          python setup.py sdist --formats=gztar
         set +x
         # Install and run tests
         set -x
@@ -157,7 +191,7 @@ jobs:
 
   test_release_opencv_python:
     if: github.event_name == 'release' && github.event.release.prerelease
-    needs: [build, build_sdist]
+    needs: [build, build_sdist, test]
     runs-on: ubuntu-latest
     environment: test-opencv-python-release
     defaults:
@@ -176,7 +210,7 @@ jobs:
 
   release_opencv_python:
     if: github.event_name == 'release' && !github.event.release.prerelease
-    needs: [build, build_sdist]
+    needs: [build, build_sdist, test]
     runs-on: ubuntu-latest
     environment: opencv-python-release
     defaults:
diff --git a/.github/workflows/build_wheels_linux_arm.yml b/.github/workflows/build_wheels_linux_arm.yml
index 89142a57..a892040b 100644
--- a/.github/workflows/build_wheels_linux_arm.yml
+++ b/.github/workflows/build_wheels_linux_arm.yml
@@ -4,6 +4,7 @@ on:
   pull_request:
     branches:
       - master
+      - 3.4
     paths-ignore:
       - '.github/workflows/build_wheels_linux.yml'
       - '.github/workflows/build_wheels_windows*'
@@ -23,7 +24,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ARM64]
-        python-version: ['3.6', '3.7', '3.8', '3.9', '3.10']
+        python-version: ['3.6']
         platform: [x64]
         with_contrib: [0, 1]
         without_gui: [0, 1]
@@ -38,12 +39,9 @@ jobs:
       TRAVIS_PYTHON_VERSION: ${{ matrix.python-version }}
       PLAT: aarch64
       MB_ML_VER: 2014
-      NP_TEST_DEP: numpy==1.19.4
-      NP_TEST_DEP_LATEST: numpy==1.21.2
       TRAVIS_BUILD_DIR: ${{ github.workspace }}
       CONFIG_PATH: travis_config.sh
-      DOCKER_IMAGE: quay.io/asenyaev/manylinux2014_${PLAT}
-      DOCKER_TEST_IMAGE: multibuild/focal_arm64v8
+      DOCKER_IMAGE: quay.io/opencv-ci/opencv-python-manylinux2014:${PLAT}
       USE_CCACHE: 0
       UNICODE_WIDTH: 32
       SDIST: ${{ matrix.build_sdist || 0 }}
@@ -61,26 +59,74 @@ jobs:
         submodules: false
         fetch-depth: 0
 
-    - name: Setup Environment variables
-      run: |
-        if [ "ARM64" == "${{ matrix.os }}" ]; then echo "PLAT=aarch64" >> $GITHUB_ENV; fi
-        if [ "3.10" == "${{ matrix.python-version }}" ]; then echo "TEST_DEPENDS=$(echo $NP_TEST_DEP_LATEST)" >> $GITHUB_ENV; else echo "TEST_DEPENDS=$(echo $NP_TEST_DEP)" >> $GITHUB_ENV; fi
-
-    - name: build
+    - name: Build a package
       run: source scripts/build.sh
 
-    - name: install and test
-      run: source scripts/install.sh
-
-    - name: saving artifacts
+    - name: Saving all wheels
       uses: actions/upload-artifact@v2
       with:
         name: wheels
         path: wheelhouse/opencv*.whl
 
+    - name: Saving a wheel accordingly to matrix
+      uses: actions/upload-artifact@v2
+      with:
+        name: wheel-${{ matrix.with_contrib }}-${{ matrix.without_gui }}-${{ matrix.build_sdist }}
+        path: wheelhouse/opencv*.whl
+
+  test:
+    needs: [build_arm]
+    runs-on: ${{ matrix.os }}
+    defaults:
+      run:
+        shell: bash
+
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ARM64]
+        python-version: ['3.6', '3.7', '3.8', '3.9', '3.10']
+        platform: [x64]
+        with_contrib: [0, 1]
+        without_gui: [0, 1]
+        build_sdist: [0]
+
+    env:
+      ACTIONS_ALLOW_UNSECURE_COMMANDS: true
+      MB_PYTHON_VERSION: ${{ matrix.python-version }}
+      PLAT: aarch64
+      NP_TEST_DEP: numpy==1.19.4
+      NP_TEST_DEP_LATEST: numpy==1.21.4
+      CONFIG_PATH: travis_config.sh
+      DOCKER_TEST_IMAGE: multibuild/focal_arm64v8
+      UNICODE_WIDTH: 32
+
+    steps:
+    - name: Cleanup
+      if: always()
+      uses: AutoModality/action-clean@v1
+
+    - name: Checkout
+      uses: actions/checkout@v2
+      with:
+        submodules: true
+        fetch-depth: 0
+
+    - name: Setup Environment variables
+      run: if [ "3.10" == "${{ matrix.python-version }}" ]; then echo "TEST_DEPENDS=$(echo $NP_TEST_DEP_LATEST)" >> $GITHUB_ENV; else echo "TEST_DEPENDS=$(echo $NP_TEST_DEP)" >> $GITHUB_ENV; fi
+
+    - name: Download a wheel accordingly to matrix
+      uses: actions/download-artifact@v2
+      with:
+        name: wheel-${{ matrix.with_contrib }}-${{ matrix.without_gui }}-${{ matrix.build_sdist }}
+        path: wheelhouse/
+
+    - name: Package installation and run tests
+      run: source scripts/install.sh
+
   test_release_opencv_python:
     if: github.event_name == 'release' && github.event.release.prerelease
-    needs: [build_arm]
+    needs: [build_arm, test]
     runs-on: ubuntu-latest
     environment: test-opencv-python-release
     defaults:
@@ -99,7 +145,7 @@ jobs:
 
   release_opencv_python:
     if: github.event_name == 'release' && !github.event.release.prerelease
-    needs: [build_arm]
+    needs: [build_arm, test]
     runs-on: ubuntu-latest
     environment: opencv-python-release
     defaults:
diff --git a/.github/workflows/build_wheels_macos.yml b/.github/workflows/build_wheels_macos.yml
index d4f10be0..c453ab85 100644
--- a/.github/workflows/build_wheels_macos.yml
+++ b/.github/workflows/build_wheels_macos.yml
@@ -4,6 +4,7 @@ on:
   pull_request:
     branches:
       - master
+      - 3.4
     paths-ignore:
       - '.github/workflows/build_wheels_linux*'
       - '.github/workflows/build_wheels_windows*'
@@ -23,7 +24,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [macos-10.15, macos-11]
-        python-version: ['3.6', '3.7', '3.8', '3.9', '3.10']
+        python-version: ['3.6']
         platform: [x64]
         with_contrib: [0, 1]
         without_gui: [0, 1]
@@ -48,14 +49,14 @@ jobs:
       MB_PYTHON_VERSION: ${{ matrix.python-version }}
       TRAVIS_PYTHON_VERSION: ${{ matrix.python-version }}
       MB_ML_VER: 2014
-      NP_TEST_DEP: numpy==1.19.4
-      NP_TEST_DEP_LATEST: numpy==1.21.2
       TRAVIS_BUILD_DIR: ${{ github.workspace }}
       TRAVIS_OS_NAME: osx
       CONFIG_PATH: travis_config.sh
       DOCKER_IMAGE: quay.io/asenyaev/manylinux2014_${PLAT}
       USE_CCACHE: 1
       UNICODE_WIDTH: 32
+      PLAT: x86_64
+      FFMPEG_FORMULA_VERSION: '@4'
       SDIST: ${{ matrix.build_sdist || 0 }}
       ENABLE_HEADLESS: ${{ matrix.without_gui }}
       ENABLE_CONTRIB: ${{ matrix.with_contrib }}
@@ -71,15 +72,7 @@ jobs:
       if: github.event_name == 'pull_request'
       run: git submodule update --remote
 
-    - name: Setup Environment variables
-      run: |
-        if [ "schedule" == "${{ github.event_name }}" ]; then echo "TRAVIS_EVENT_TYPE=cron" >> $GITHUB_ENV; else echo "TRAVIS_EVENT_TYPE=${{ github.event_name }}" >> $GITHUB_ENV; fi
-        if [ "schedule" == "${{ github.event_name }}" ]; then echo "BUILD_COMMIT=master" >> $GITHUB_ENV; else echo "BUILD_COMMIT=$BUILD_COMMIT" >> $GITHUB_ENV; fi
-        if [ "x64" == "${{ matrix.platform }}" ]; then echo "PLAT=x86_64" >> $GITHUB_ENV; fi
-        if [ "x86" == "${{ matrix.platform }}" ]; then echo "PLAT=i686" >> $GITHUB_ENV; fi
-        if [ "3.10" == "${{ matrix.python-version }}" ]; then echo "TEST_DEPENDS=$(echo $NP_TEST_DEP_LATEST)" >> $GITHUB_ENV; else echo "TEST_DEPENDS=$(echo $NP_TEST_DEP)" >> $GITHUB_ENV; fi
-
-    - name: before install
+    - name: Build a package
       run: |
         set -e
         # Check out and prepare the source
@@ -96,19 +89,99 @@ jobs:
         echo $ENABLE_HEADLESS > headless.enabled
         set -x
         build_wheel $REPO_DIR $PLAT
-        git submodule update --init --recursive
-        install_run $PLAT
-        set +x
 
-    - name: saving artifacts
+    - name: Saving all wheels
       uses: actions/upload-artifact@v2
       with:
         name: wheels
         path: wheelhouse/opencv*.whl
 
+    - name: Saving a wheel accordingly to matrix
+      uses: actions/upload-artifact@v2
+      with:
+        name: wheel-${{ matrix.with_contrib }}-${{ matrix.without_gui }}-${{ matrix.build_sdist }}
+        path: wheelhouse/opencv*.whl
+
+  test:
+    needs: [build]
+    runs-on: ${{ matrix.os }}
+    defaults:
+      run:
+        shell: bash
+
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [macos-10.15, macos-11]
+        python-version: ['3.6', '3.7', '3.8', '3.9', '3.10']
+        platform: [x64]
+        with_contrib: [0, 1]
+        without_gui: [0, 1]
+        build_sdist: [0]
+        exclude:
+          - os: macos-10.15
+            python-version: '3.10'
+          - os: macos-11
+            python-version: '3.6'
+          - os: macos-11
+            python-version: '3.7'
+          - os: macos-11
+            python-version: '3.8'
+          - os: macos-11
+            python-version: '3.9'
+
+    env:
+      ACTIONS_ALLOW_UNSECURE_COMMANDS: true
+      MB_PYTHON_VERSION: ${{ matrix.python-version }}
+      NP_TEST_DEP: numpy==1.19.4
+      NP_TEST_DEP_LATEST: numpy==1.21.4
+      CONFIG_PATH: travis_config.sh
+      PLAT: x86_64
+      OPENCV_TEST_DATA_PATH: ${{ github.workspace }}/opencv_extra/testdata
+      PYLINT_TEST_FILE: ${{ github.workspace }}/opencv/samples/python/squares.py
+
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v2
+      with:
+        submodules: true
+        fetch-depth: 0
+
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v2
+      with:
+        python-version: ${{ matrix.python-version }}
+        architecture: ${{ matrix.platform }}
+
+    - name: Setup Environment variables
+      run: if [ "3.10" == "${{ matrix.python-version }}" ]; then echo "TEST_DEPENDS=$(echo $NP_TEST_DEP_LATEST)" >> $GITHUB_ENV; else echo "TEST_DEPENDS=$(echo $NP_TEST_DEP)" >> $GITHUB_ENV; fi
+
+    - name: Download a wheel accordingly to matrix
+      uses: actions/download-artifact@v2
+      with:
+        name: wheel-${{ matrix.with_contrib }}-${{ matrix.without_gui }}-${{ matrix.build_sdist }}
+        path: wheelhouse/
+
+    - name: Package installation
+      run: |
+        python -m pip install wheelhouse/opencv*.whl
+        cd ${{ github.workspace }}/tests
+        python get_build_info.py
+
+    - name: Run tests
+      run: |
+        cd ${{ github.workspace }}/opencv
+        python modules/python/test/test.py -v --repo .
+
+    - name: Pylint test
+      run: |
+        python -m pip install pylint==2.12.2
+        cd ${{ github.workspace }}/tests
+        python -m pylint $PYLINT_TEST_FILE
+
   test_release_opencv_python:
     if: github.event_name == 'release' && github.event.release.prerelease
-    needs: [build]
+    needs: [build, test]
     runs-on: ubuntu-latest
     environment: test-opencv-python-release
     defaults:
@@ -127,7 +200,7 @@ jobs:
 
   release_opencv_python:
     if: github.event_name == 'release' && !github.event.release.prerelease
-    needs: [build]
+    needs: [build, test]
     runs-on: ubuntu-latest
     environment: opencv-python-release
     defaults:
diff --git a/.github/workflows/build_wheels_macos_m1.yml b/.github/workflows/build_wheels_macos_m1.yml
index 79164dcf..1ac065f1 100644
--- a/.github/workflows/build_wheels_macos_m1.yml
+++ b/.github/workflows/build_wheels_macos_m1.yml
@@ -4,6 +4,7 @@ on:
   pull_request:
     branches:
       - master
+      - 3.4
     paths-ignore:
       - '.github/workflows/build_wheels_linux*'
       - '.github/workflows/build_wheels_windows*'
@@ -20,7 +21,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [macOS-M1]
-        python-version: ['3.7', '3.8', '3.9', '3.10']
+        python-version: ['3.7']
         platform: [x64]
         with_contrib: [0, 1]
         without_gui: [0, 1]
@@ -31,7 +32,6 @@ jobs:
       SDIST: ${{ matrix.build_sdist || 0 }}
       ENABLE_HEADLESS: ${{ matrix.without_gui }}
       ENABLE_CONTRIB: ${{ matrix.with_contrib }}
-      OPENCV_TEST_DATA_PATH: ${{ github.workspace }}/opencv_extra/testdata
 
     steps:
     - name: Checkout
@@ -44,36 +44,79 @@ jobs:
       if: github.event_name == 'pull_request'
       run: git submodule update --remote
 
-    - name: build script
+    - name: Build a package
       run: |
         git submodule update --init multibuild
         echo $ENABLE_CONTRIB > contrib.enabled
         echo $ENABLE_HEADLESS > headless.enabled
         export MACOSX_DEPLOYMENT_TARGET=11.0
-        arch -arm64 python${{ matrix.python-version }} -m pip wheel --wheel-dir=wheelhouse . --verbose
+        arch -arm64 python${{ matrix.python-version }} -m pip install toml && python${{ matrix.python-version }} -c 'import toml; c = toml.load("pyproject.toml"); print("\n".join(c["build-system"]["requires"]))' | python${{ matrix.python-version }} -m pip install -r /dev/stdin
+        arch -arm64 python${{ matrix.python-version }} setup.py bdist_wheel --py-limited-api=cp37 --dist-dir=wheelhouse -v
         delocate-wheel ${{ github.workspace }}/wheelhouse/opencv*
 
-    - name: before test
+    - name: Saving all wheels
+      uses: actions/upload-artifact@v2
+      with:
+        name: wheels
+        path: wheelhouse/opencv*.whl
+
+    - name: Saving a wheel accordingly to matrix
+      uses: actions/upload-artifact@v2
+      with:
+        name: wheel-${{ matrix.with_contrib }}-${{ matrix.without_gui }}-${{ matrix.build_sdist }}
+        path: wheelhouse/opencv*.whl
+
+  test:
+    needs: [build]
+    runs-on: ${{ matrix.os }}
+
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [macOS-M1]
+        python-version: ['3.7', '3.8', '3.9', '3.10']
+        platform: [x64]
+        with_contrib: [0, 1]
+        without_gui: [0, 1]
+        build_sdist: [0]
+
+    env:
+      OPENCV_TEST_DATA_PATH: ${{ github.workspace }}/opencv_extra/testdata
+      PYLINT_TEST_FILE: ${{ github.workspace }}/opencv/samples/python/squares.py
+
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v2
+      with:
+        submodules: true
+        fetch-depth: 0
+
+    - name: Download a wheel accordingly to matrix
+      uses: actions/download-artifact@v2
+      with:
+        name: wheel-${{ matrix.with_contrib }}-${{ matrix.without_gui }}-${{ matrix.build_sdist }}
+        path: wheelhouse/
+
+    - name: Package installation
       run: |
-        git submodule update --init --recursive
         arch -arm64 python${{ matrix.python-version }} -m pip install --user --no-cache --force-reinstall wheelhouse/opencv*.whl
         cd ${{ github.workspace }}/tests
         arch -arm64 python${{ matrix.python-version }} get_build_info.py
 
-    - name: run test
+    - name: Run tests
       run: |
         cd ${{ github.workspace }}/opencv
         arch -arm64 python${{ matrix.python-version }} modules/python/test/test.py -v --repo .
 
-    - name: saving artifacts
-      uses: actions/upload-artifact@v2
-      with:
-        name: wheels
-        path: wheelhouse/opencv*.whl
+    - name: Pylint test
+      run: |
+        arch -arm64 python${{ matrix.python-version }} -m pip install pylint==2.12.2
+        cd ${{ github.workspace }}/tests
+        arch -arm64 python${{ matrix.python-version }} -m pylint $PYLINT_TEST_FILE
 
   test_release_opencv_python:
     if: github.event_name == 'release' && github.event.release.prerelease
-    needs: [build]
+    needs: [build, test]
     runs-on: ubuntu-latest
     environment: test-opencv-python-release
     defaults:
@@ -92,7 +135,7 @@ jobs:
 
   release_opencv_python:
     if: github.event_name == 'release' && !github.event.release.prerelease
-    needs: [build]
+    needs: [build, test]
     runs-on: ubuntu-latest
     environment: opencv-python-release
     defaults:
diff --git a/.github/workflows/build_wheels_windows.yml b/.github/workflows/build_wheels_windows.yml
index 3eb13086..0dad17b5 100644
--- a/.github/workflows/build_wheels_windows.yml
+++ b/.github/workflows/build_wheels_windows.yml
@@ -4,6 +4,7 @@ on:
   pull_request:
     branches:
       - master
+      - 3.4
     paths-ignore:
       - '.github/workflows/build_wheels_linux*'
       - '.github/workflows/build_wheels_macos*'
@@ -21,8 +22,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [windows-latest]
-        python-version: ['3.6', '3.7', '3.8', '3.9', '3.10']
+        os: [windows-2019]
+        python-version: ['3.6']
         platform: [x86, x64]
         with_contrib: [0, 1]
         without_gui: [0, 1]
@@ -53,40 +54,94 @@ jobs:
         architecture: ${{ matrix.platform }}
 
     - name: Setup MSBuild.exe
-      uses: warrenbuckley/Setup-MSBuild@v1
+      uses: microsoft/setup-msbuild@v1.1
 
-    - name: build script
+    - name: Build a package
       run: |
         python --version
         python -m pip install --upgrade pip
         python -m pip install --upgrade setuptools
-        set "CI_BUILD=1" && python -m pip wheel --wheel-dir=%cd%\wheelhouse . --verbose
+        python -m pip install toml && python -c "import toml; c = toml.load('pyproject.toml'); print('\n'.join(c['build-system']['requires']))" >> requirements.txt | python -m pip install -r requirements.txt
+        set "CI_BUILD=1" && python setup.py bdist_wheel --py-limited-api=cp36 --dist-dir=%cd%\wheelhouse -v
       shell: cmd
 
-    - name: before test
+    - name: Saving all wheels
+      uses: actions/upload-artifact@v2
+      with:
+        name: wheels
+        path: wheelhouse/opencv*.whl
+
+    - name: Saving a wheel accordingly to matrix
+      uses: actions/upload-artifact@v2
+      with:
+        name: wheel-${{ matrix.with_contrib }}-${{ matrix.without_gui }}-${{ matrix.build_sdist }}-${{ matrix.platform }}
+        path: wheelhouse/opencv*
+
+  test:
+    needs: [build-windows-x86_64]
+    runs-on: ${{ matrix.os }}
+    defaults:
+      run:
+        shell: powershell
+
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [windows-2019]
+        python-version: ['3.6', '3.7', '3.8', '3.9', '3.10']
+        platform: [x86, x64]
+        with_contrib: [0, 1]
+        without_gui: [0, 1]
+        build_sdist: [0]
+
+    env:
+      ACTIONS_ALLOW_UNSECURE_COMMANDS: true
+      OPENCV_TEST_DATA_PATH: ${{ github.workspace }}\opencv_extra\testdata
+      PYLINT_TEST_FILE: ${{ github.workspace }}\opencv\samples\python\squares.py
+
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v2
+      with:
+        submodules: true
+        fetch-depth: 0
+
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v2
+      with:
+        python-version: ${{ matrix.python-version }}
+        architecture: ${{ matrix.platform }}
+
+    - name: Download a wheel accordingly to matrix
+      uses: actions/download-artifact@v2
+      with:
+        name: wheel-${{ matrix.with_contrib }}-${{ matrix.without_gui }}-${{ matrix.build_sdist }}-${{ matrix.platform }}
+        path: wheelhouse/
+
+    - name: Package installation
       run: |
-        git submodule update --init --recursive
         cd ${{ github.workspace }}/tests
         &python -m pip install --user --no-warn-script-location (ls "../wheelhouse/opencv*.whl")
         if ($LastExitCode -ne 0) {throw $LastExitCode}
         python get_build_info.py
       shell: powershell
 
-    - name: run test
+    - name: Run tests
       run: |
         cd ${{ github.workspace }}/opencv
         python modules\python\test\test.py -v --repo .
       shell: cmd
 
-    - name: saving artifacts
-      uses: actions/upload-artifact@v2
-      with:
-        name: wheels
-        path: wheelhouse/opencv*.whl
+    - name: Pylint test
+      run: |
+        python -m pip install pylint==2.12.2
+        cd ${{ github.workspace }}\tests
+        python -m pylint $PYLINT_TEST_FILE
+      shell: cmd
 
   test_release_opencv_python:
     if: github.event_name == 'release' && github.event.release.prerelease
-    needs: [build-windows-x86_64]
+    needs: [build-windows-x86_64, test]
     runs-on: ubuntu-latest
     environment: test-opencv-python-release
     defaults:
@@ -105,7 +160,7 @@ jobs:
 
   release_opencv_python:
     if: github.event_name == 'release' && !github.event.release.prerelease
-    needs: [build-windows-x86_64]
+    needs: [build-windows-x86_64, test]
     runs-on: ubuntu-latest
     environment: opencv-python-release
     defaults:
diff --git a/.gitmodules b/.gitmodules
index 655467e8..8ebdff3d 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,12 +1,15 @@
 [submodule "opencv"]
 	path = opencv
 	url = https://github.com/opencv/opencv.git
+        branch = 3.4
 [submodule "opencv_contrib"]
 	path = opencv_contrib
 	url = https://github.com/opencv/opencv_contrib.git
+        branch = 3.4
 [submodule "multibuild"]
 	path = multibuild
 	url = https://github.com/matthew-brett/multibuild.git
 [submodule "opencv_extra"]
 	path = opencv_extra
 	url = https://github.com/opencv/opencv_extra.git
+        branch = 3.4
diff --git a/LICENSE-3RD-PARTY.txt b/LICENSE-3RD-PARTY.txt
index 20f4fb37..1db522f7 100644
--- a/LICENSE-3RD-PARTY.txt
+++ b/LICENSE-3RD-PARTY.txt
@@ -1,208 +1,48 @@
 OpenCV library is redistributed within opencv-python package.
 This license applies to OpenCV binary in the directory cv2/.
 
+By downloading, copying, installing or using the software you agree to this license.
+If you do not agree to this license, do not download, install,
+copy or use the software.
 
-                                 Apache License
-                           Version 2.0, January 2004
-                        http://www.apache.org/licenses/
-
-   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
-
-   1. Definitions.
-
-      "License" shall mean the terms and conditions for use, reproduction,
-      and distribution as defined by Sections 1 through 9 of this document.
-
-      "Licensor" shall mean the copyright owner or entity authorized by
-      the copyright owner that is granting the License.
-
-      "Legal Entity" shall mean the union of the acting entity and all
-      other entities that control, are controlled by, or are under common
-      control with that entity. For the purposes of this definition,
-      "control" means (i) the power, direct or indirect, to cause the
-      direction or management of such entity, whether by contract or
-      otherwise, or (ii) ownership of fifty percent (50%) or more of the
-      outstanding shares, or (iii) beneficial ownership of such entity.
-
-      "You" (or "Your") shall mean an individual or Legal Entity
-      exercising permissions granted by this License.
-
-      "Source" form shall mean the preferred form for making modifications,
-      including but not limited to software source code, documentation
-      source, and configuration files.
-
-      "Object" form shall mean any form resulting from mechanical
-      transformation or translation of a Source form, including but
-      not limited to compiled object code, generated documentation,
-      and conversions to other media types.
-
-      "Work" shall mean the work of authorship, whether in Source or
-      Object form, made available under the License, as indicated by a
-      copyright notice that is included in or attached to the work
-      (an example is provided in the Appendix below).
-
-      "Derivative Works" shall mean any work, whether in Source or Object
-      form, that is based on (or derived from) the Work and for which the
-      editorial revisions, annotations, elaborations, or other modifications
-      represent, as a whole, an original work of authorship. For the purposes
-      of this License, Derivative Works shall not include works that remain
-      separable from, or merely link (or bind by name) to the interfaces of,
-      the Work and Derivative Works thereof.
-
-      "Contribution" shall mean any work of authorship, including
-      the original version of the Work and any modifications or additions
-      to that Work or Derivative Works thereof, that is intentionally
-      submitted to Licensor for inclusion in the Work by the copyright owner
-      or by an individual or Legal Entity authorized to submit on behalf of
-      the copyright owner. For the purposes of this definition, "submitted"
-      means any form of electronic, verbal, or written communication sent
-      to the Licensor or its representatives, including but not limited to
-      communication on electronic mailing lists, source code control systems,
-      and issue tracking systems that are managed by, or on behalf of, the
-      Licensor for the purpose of discussing and improving the Work, but
-      excluding communication that is conspicuously marked or otherwise
-      designated in writing by the copyright owner as "Not a Contribution."
-
-      "Contributor" shall mean Licensor and any individual or Legal Entity
-      on behalf of whom a Contribution has been received by Licensor and
-      subsequently incorporated within the Work.
-
-   2. Grant of Copyright License. Subject to the terms and conditions of
-      this License, each Contributor hereby grants to You a perpetual,
-      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
-      copyright license to reproduce, prepare Derivative Works of,
-      publicly display, publicly perform, sublicense, and distribute the
-      Work and such Derivative Works in Source or Object form.
-
-   3. Grant of Patent License. Subject to the terms and conditions of
-      this License, each Contributor hereby grants to You a perpetual,
-      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
-      (except as stated in this section) patent license to make, have made,
-      use, offer to sell, sell, import, and otherwise transfer the Work,
-      where such license applies only to those patent claims licensable
-      by such Contributor that are necessarily infringed by their
-      Contribution(s) alone or by combination of their Contribution(s)
-      with the Work to which such Contribution(s) was submitted. If You
-      institute patent litigation against any entity (including a
-      cross-claim or counterclaim in a lawsuit) alleging that the Work
-      or a Contribution incorporated within the Work constitutes direct
-      or contributory patent infringement, then any patent licenses
-      granted to You under this License for that Work shall terminate
-      as of the date such litigation is filed.
-
-   4. Redistribution. You may reproduce and distribute copies of the
-      Work or Derivative Works thereof in any medium, with or without
-      modifications, and in Source or Object form, provided that You
-      meet the following conditions:
-
-      (a) You must give any other recipients of the Work or
-          Derivative Works a copy of this License; and
-
-      (b) You must cause any modified files to carry prominent notices
-          stating that You changed the files; and
-
-      (c) You must retain, in the Source form of any Derivative Works
-          that You distribute, all copyright, patent, trademark, and
-          attribution notices from the Source form of the Work,
-          excluding those notices that do not pertain to any part of
-          the Derivative Works; and
-
-      (d) If the Work includes a "NOTICE" text file as part of its
-          distribution, then any Derivative Works that You distribute must
-          include a readable copy of the attribution notices contained
-          within such NOTICE file, excluding those notices that do not
-          pertain to any part of the Derivative Works, in at least one
-          of the following places: within a NOTICE text file distributed
-          as part of the Derivative Works; within the Source form or
-          documentation, if provided along with the Derivative Works; or,
-          within a display generated by the Derivative Works, if and
-          wherever such third-party notices normally appear. The contents
-          of the NOTICE file are for informational purposes only and
-          do not modify the License. You may add Your own attribution
-          notices within Derivative Works that You distribute, alongside
-          or as an addendum to the NOTICE text from the Work, provided
-          that such additional attribution notices cannot be construed
-          as modifying the License.
-
-      You may add Your own copyright statement to Your modifications and
-      may provide additional or different license terms and conditions
-      for use, reproduction, or distribution of Your modifications, or
-      for any such Derivative Works as a whole, provided Your use,
-      reproduction, and distribution of the Work otherwise complies with
-      the conditions stated in this License.
-
-   5. Submission of Contributions. Unless You explicitly state otherwise,
-      any Contribution intentionally submitted for inclusion in the Work
-      by You to the Licensor shall be under the terms and conditions of
-      this License, without any additional terms or conditions.
-      Notwithstanding the above, nothing herein shall supersede or modify
-      the terms of any separate license agreement you may have executed
-      with Licensor regarding such Contributions.
-
-   6. Trademarks. This License does not grant permission to use the trade
-      names, trademarks, service marks, or product names of the Licensor,
-      except as required for reasonable and customary use in describing the
-      origin of the Work and reproducing the content of the NOTICE file.
-
-   7. Disclaimer of Warranty. Unless required by applicable law or
-      agreed to in writing, Licensor provides the Work (and each
-      Contributor provides its Contributions) on an "AS IS" BASIS,
-      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
-      implied, including, without limitation, any warranties or conditions
-      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
-      PARTICULAR PURPOSE. You are solely responsible for determining the
-      appropriateness of using or redistributing the Work and assume any
-      risks associated with Your exercise of permissions under this License.
-
-   8. Limitation of Liability. In no event and under no legal theory,
-      whether in tort (including negligence), contract, or otherwise,
-      unless required by applicable law (such as deliberate and grossly
-      negligent acts) or agreed to in writing, shall any Contributor be
-      liable to You for damages, including any direct, indirect, special,
-      incidental, or consequential damages of any character arising as a
-      result of this License or out of the use or inability to use the
-      Work (including but not limited to damages for loss of goodwill,
-      work stoppage, computer failure or malfunction, or any and all
-      other commercial damages or losses), even if such Contributor
-      has been advised of the possibility of such damages.
-
-   9. Accepting Warranty or Additional Liability. While redistributing
-      the Work or Derivative Works thereof, You may choose to offer,
-      and charge a fee for, acceptance of support, warranty, indemnity,
-      or other liability obligations and/or rights consistent with this
-      License. However, in accepting such obligations, You may act only
-      on Your own behalf and on Your sole responsibility, not on behalf
-      of any other Contributor, and only if You agree to indemnify,
-      defend, and hold each Contributor harmless for any liability
-      incurred by, or claims asserted against, such Contributor by reason
-      of your accepting any such warranty or additional liability.
-
-   END OF TERMS AND CONDITIONS
-
-   APPENDIX: How to apply the Apache License to your work.
-
-      To apply the Apache License to your work, attach the following
-      boilerplate notice, with the fields enclosed by brackets "[]"
-      replaced with your own identifying information. (Don't include
-      the brackets!)  The text should be enclosed in the appropriate
-      comment syntax for the file format. We also recommend that a
-      file or class name and description of purpose be included on the
-      same "printed page" as the copyright notice for easier
-      identification within third-party archives.
-
-   Copyright [yyyy] [name of copyright owner]
-
-   Licensed under the Apache License, Version 2.0 (the "License");
-   you may not use this file except in compliance with the License.
-   You may obtain a copy of the License at
-
-       http://www.apache.org/licenses/LICENSE-2.0
-
-   Unless required by applicable law or agreed to in writing, software
-   distributed under the License is distributed on an "AS IS" BASIS,
-   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-   See the License for the specific language governing permissions and
-   limitations under the License.
+
+                          License Agreement
+               For Open Source Computer Vision Library
+                       (3-clause BSD License)
+
+Copyright (C) 2000-2021, Intel Corporation, all rights reserved.
+Copyright (C) 2009-2011, Willow Garage Inc., all rights reserved.
+Copyright (C) 2009-2016, NVIDIA Corporation, all rights reserved.
+Copyright (C) 2010-2013, Advanced Micro Devices, Inc., all rights reserved.
+Copyright (C) 2015-2021, OpenCV Foundation, all rights reserved.
+Copyright (C) 2015-2016, Itseez Inc., all rights reserved.
+Copyright (C) 2019-2021, Xperience AI, all rights reserved.
+Third party copyrights are property of their respective owners.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+  * Redistributions of source code must retain the above copyright notice,
+    this list of conditions and the following disclaimer.
+
+  * Redistributions in binary form must reproduce the above copyright notice,
+    this list of conditions and the following disclaimer in the documentation
+    and/or other materials provided with the distribution.
+
+  * Neither the names of the copyright holders nor the names of the contributors
+    may be used to endorse or promote products derived from this software
+    without specific prior written permission.
+
+This software is provided by the copyright holders and contributors "as is" and
+any express or implied warranties, including, but not limited to, the implied
+warranties of merchantability and fitness for a particular purpose are disclaimed.
+In no event shall copyright holders or contributors be liable for any direct,
+indirect, incidental, special, exemplary, or consequential damages
+(including, but not limited to, procurement of substitute goods or services;
+loss of use, data, or profits; or business interruption) however caused
+and on any theory of liability, whether in contract, strict liability,
+or tort (including negligence or otherwise) arising in any way out of
+the use of this software, even if advised of the possibility of such damage.
 
 ------------------------------------------------------------------------------
 libvpx is redistributed within all opencv-python Linux packages.
@@ -1000,7 +840,7 @@ This license applies to above binaries in the directory cv2/.
  * The implementation was written so as to conform with Netscapes SSL.
  *
  * This library is free for commercial and non-commercial use as long as
- * the following conditions are aheared to.  The following conditions
+ * the following conditions are adhered to.  The following conditions
  * apply to all code found in this distribution, be it the RC4, RSA,
  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  * included with this distribution is covered by the same copyright terms
@@ -1025,7 +865,7 @@ This license applies to above binaries in the directory cv2/.
  *    must display the following acknowledgement:
  *    "This product includes cryptographic software written by
  *     Eric Young (eay@cryptsoft.com)"
- *    The word 'cryptographic' can be left out if the rouines from the library
+ *    The word 'cryptographic' can be left out if the routines from the library
  *    being used are not cryptographic related :-).
  * 4. If you include any Windows specific code (or a derivative thereof) from
  *    the apps directory (application code) you must include an acknowledgement:
@@ -1043,7 +883,7 @@ This license applies to above binaries in the directory cv2/.
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- * The licence and distribution terms for any publically available version or
+ * The licence and distribution terms for any publicly available version or
  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  * copied and put under another distribution licence
  * [including the GNU Public Licence.]
diff --git a/MANIFEST.in b/MANIFEST.in
index 45cb6c40..b429eae0 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -9,3 +9,4 @@ recursive-include docker *
 recursive-include opencv *
 recursive-include opencv_contrib *
 recursive-include patches *
+recursive-include scripts *.py
diff --git a/README.md b/README.md
index d2831332..522cc005 100644
--- a/README.md
+++ b/README.md
@@ -79,7 +79,7 @@ A: It's easier for users to understand ``opencv-python`` than ``cv2`` and it mak
 
 ## Documentation for opencv-python
 
-[![Windows Buld Status](https://github.com/opencv/opencv-python/actions/workflows/build_wheels_windows.yml/badge.svg)](https://github.com/opencv/opencv-python/actions/workflows/build_wheels_windows.yml)
+[![Windows Build Status](https://github.com/opencv/opencv-python/actions/workflows/build_wheels_windows.yml/badge.svg)](https://github.com/opencv/opencv-python/actions/workflows/build_wheels_windows.yml)
 [![(Linux Build status)](https://github.com/opencv/opencv-python/actions/workflows/build_wheels_linux.yml/badge.svg)](https://github.com/opencv/opencv-python/actions/workflows/build_wheels_linux.yml)
 [![(Mac OS Build status)](https://github.com/opencv/opencv-python/actions/workflows/build_wheels_macos.yml/badge.svg)](https://github.com/opencv/opencv-python/actions/workflows/build_wheels_macos.yml)
 
@@ -176,7 +176,7 @@ On slow systems such as Raspberry Pi the full build may take several hours. On a
 
 Opencv-python package (scripts in this repository) is available under MIT license.
 
-OpenCV itself is available under [Apache 2](https://github.com/opencv/opencv/blob/master/LICENSE) license.
+OpenCV itself is available under [3-clause BSD License](https://github.com/opencv/opencv/blob/master/LICENSE).
 
 Third party package licenses are at [LICENSE-3RD-PARTY.txt](https://github.com/opencv/opencv-python/blob/master/LICENSE-3RD-PARTY.txt).
 
@@ -220,6 +220,7 @@ Python 3.x compatible pre-built wheels are provided for the officially supported
 - 3.7
 - 3.8
 - 3.9
+- 3.10
 
 ### Backward compatibility
 
diff --git a/appveyor.yml b/appveyor.yml
deleted file mode 100644
index c79e7de4..00000000
--- a/appveyor.yml
+++ /dev/null
@@ -1,201 +0,0 @@
-environment:
-  USER:
-    secure: fXgF9uyy6sT0JoVOR7BoqA==
-
-  PASS:
-    secure: 0bXSOVjf9x8L7nErTivu92TF1FwNosTjFJQPmxp8Dys=
-
-  matrix:
-    - PYTHON: "C:\\Python36"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python36-x64"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python37"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python37-x64"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python38"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python38-x64"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python39"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python39-x64"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python36"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python36-x64"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python37"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python37-x64"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python38"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python38-x64"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python39"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python39-x64"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 0
-
-    - PYTHON: "C:\\Python36"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python36-x64"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python37"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python37-x64"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python38"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python38-x64"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python39"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python39-x64"
-      ENABLE_CONTRIB: 0
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python36"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python36-x64"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python37"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python37-x64"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python38"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python38-x64"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python39"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 1
-
-    - PYTHON: "C:\\Python39-x64"
-      ENABLE_CONTRIB: 1
-      ENABLE_HEADLESS: 1
-
-matrix:
-    fast_finish: true
-
-install:
-  - ps: |
-      if (-not (Test-Path $env:PYTHON)) {
-        curl -o install_python.ps1 https://raw.githubusercontent.com/matthew-brett/multibuild/devel/install_python.ps1
-        .\install_python.ps1
-      }
-  - ps: if (-not (Test-Path $env:PYTHON)) { throw "No $env:PYTHON" }
-  - "set PATH=%PYTHON%;%PYTHON%\\Scripts;%PATH%"
-  - python --version
-
-build_script:
-- cmd: |
-    "%PYTHON%\\python.exe" -m pip install --upgrade pip
-    "%PYTHON%\\python.exe" -m pip install --upgrade setuptools
-    set "CI_BUILD=1" && "%PYTHON%\\python.exe" -m pip wheel --wheel-dir=%cd%\dist . --verbose
-
-before_test:
-- ps: |
-
-    cd ${Env:APPVEYOR_BUILD_FOLDER}\tests
-    $env:PYTHONWARNINGS = "ignore:::pip._internal.cli.base_command"
-    &"${Env:PYTHON}\\python.exe" -m pip install --user --no-warn-script-location (ls "../dist/opencv_*.whl")
-    if ($LastExitCode -ne 0) {throw $LastExitCode}
-
-test_script:
-- cmd: |
-
-    cd %APPVEYOR_BUILD_FOLDER%\tests
-    "%PYTHON%\\python.exe" -m unittest test
-
-artifacts:
-- path: dist\opencv*.whl
-  name: wheels
-
-deploy_script:
-- ps: |
-
-    if (${Env:APPVEYOR_REPO_TAG} -eq "true") {
-      cd ${Env:APPVEYOR_BUILD_FOLDER}
-      if (${Env:ENABLE_CONTRIB} -eq 0) {
-        if (${Env:ENABLE_HEADLESS} -eq 0) {
-          echo "This is a default build. Deployment will be done to PyPI entry opencv-python."
-        }
-        else {
-          echo "This is a headless build. Deployment will be done to PyPI entry opencv-python-headless."
-        }
-      }
-      else {
-        if (${Env:ENABLE_HEADLESS} -eq 0) {
-          echo "This is a contrib build. Deployment will be done to PyPI entry opencv-contrib-python."
-        }
-        else {
-          echo "This is a headless contrib build. Deployment will be done to PyPI entry opencv-contrib-python-headless."
-        }
-      }
-
-      &"${Env:PYTHON}\\python.exe" -m pip install twine
-      &"${Env:PYTHON}\\python.exe" -m twine upload -u ${Env:USER} -p ${Env:PASS} --skip-existing dist/opencv*
-    }
-    else {
-      echo "Tag not set, deployment skipped."
-    }
diff --git a/docker/manylinux2014/Dockerfile_aarch64 b/docker/manylinux2014/Dockerfile_aarch64
index c76ccec4..03889a51 100644
--- a/docker/manylinux2014/Dockerfile_aarch64
+++ b/docker/manylinux2014/Dockerfile_aarch64
@@ -1,72 +1,128 @@
 FROM quay.io/pypa/manylinux2014_aarch64:latest
 
-RUN yum install bzip2-devel curl-devel zlib-devel xcb-util-renderutil-devel xcb-util-devel xcb-util-image-devel xcb-util-keysyms-devel xcb-util-wm-devel mesa-libGL-devel libxkbcommon-devel libxkbcommon-x11-devel libXi-devel freetype-devel -y
+ARG CCACHE_VERSION=3.7.9
+ARG FFMPEG_VERSION=4.4.1
+ARG FREETYPE_VERSION=2.12.1
+ARG LIBPNG_VERSION=1.6.37
+ARG NASM_VERSION=2.15.04
+ARG OPENSSL_VERSION=1_1_1o
+ARG QT_VERSION=5.15.0
+ARG YASM_VERSION=1.3.0
 
-RUN curl -O -L https://download.qt.io/official_releases/qt/5.15/5.15.0/single/qt-everywhere-src-5.15.0.tar.xz && \
-    tar -xf qt-everywhere-src-5.15.0.tar.xz && \
-    cd qt-everywhere* && \
+ENV LD_LIBRARY_PATH /usr/local/lib:$LD_LIBRARY_PATH
+
+# epel-release need for aarch64 to get openblas packages
+RUN yum install bzip2-devel curl-devel zlib-devel xcb-util-renderutil-devel xcb-util-devel xcb-util-image-devel xcb-util-keysyms-devel xcb-util-wm-devel mesa-libGL-devel libxkbcommon-devel libxkbcommon-x11-devel libXi-devel lapack-devel epel-release -y && \
+    yum install openblas-devel -y && \
+    cp /usr/include/lapacke/lapacke*.h /usr/include/ && \
+    curl https://raw.githubusercontent.com/xianyi/OpenBLAS/v0.3.3/cblas.h -o /usr/include/cblas.h && \
+    # libpng will be built from source
+    yum remove libpng -y
+
+RUN mkdir ~/libpng_sources && \
+    cd ~/libpng_sources && \
+    curl -O -L https://download.sourceforge.net/libpng/libpng-${LIBPNG_VERSION}.tar.gz && \
+    tar -xf libpng-${LIBPNG_VERSION}.tar.gz && \
+    cd libpng-${LIBPNG_VERSION} && \
+    ./configure --prefix=/usr/local && \
+    make && \
+    make install && \
+    cd .. && \
+    rm -rf ~/libpng_sources
+
+RUN mkdir ~/freetype_sources && \
+    cd ~/freetype_sources && \
+    curl -O -L https://download.savannah.gnu.org/releases/freetype/freetype-${FREETYPE_VERSION}.tar.gz && \
+    tar -xf freetype-${FREETYPE_VERSION}.tar.gz && \
+    cd freetype-${FREETYPE_VERSION} && \
+    ./configure --prefix="$HOME/ffmpeg_build" --enable-freetype-config && \
+    make && \
+    make install && \
+    cd .. && \
+    rm -rf ~/freetype_sources
+
+RUN curl -O -L https://download.qt.io/official_releases/qt/5.15/${QT_VERSION}/single/qt-everywhere-src-${QT_VERSION}.tar.xz && \
+    tar -xf qt-everywhere-src-${QT_VERSION}.tar.xz && \
+    cd qt-everywhere-src-${QT_VERSION} && \
     export MAKEFLAGS=-j$(nproc) && \
-    ./configure -prefix /opt/Qt5.15.0 -release -opensource -confirm-license -qtnamespace QtOpenCVPython -xcb -xcb-xlib -bundled-xcb-xinput -no-openssl -no-dbus -skip qt3d -skip qtactiveqt -skip qtcanvas3d -skip qtconnectivity -skip qtdatavis3d -skip qtdoc -skip qtgamepad -skip qtgraphicaleffects -skip qtimageformats -skip qtlocation -skip qtmultimedia -skip qtpurchasing -skip qtqa -skip qtremoteobjects -skip qtrepotools -skip qtscript -skip qtscxml -skip qtsensors -skip qtserialbus -skip qtserialport -skip qtspeech -skip qttranslations -skip qtwayland -skip qtwebchannel -skip qtwebengine -skip qtwebsockets -skip qtwebview -skip xmlpatterns -skip declarative -make libs && \
+    ./configure -prefix /opt/Qt${QT_VERSION} -release -opensource -confirm-license -qtnamespace QtOpenCVPython -xcb -xcb-xlib -bundled-xcb-xinput -no-openssl -no-dbus -skip qt3d -skip qtactiveqt -skip qtcanvas3d -skip qtconnectivity -skip qtdatavis3d -skip qtdoc -skip qtgamepad -skip qtgraphicaleffects -skip qtimageformats -skip qtlocation -skip qtmultimedia -skip qtpurchasing -skip qtqa -skip qtremoteobjects -skip qtrepotools -skip qtscript -skip qtscxml -skip qtsensors -skip qtserialbus -skip qtserialport -skip qtspeech -skip qttranslations -skip qtwayland -skip qtwebchannel -skip qtwebengine -skip qtwebsockets -skip qtwebview -skip xmlpatterns -skip declarative -make libs && \
     make && \
     make install && \
     cd .. && \
-    rm -rf qt-everywhere-src-5.15.0 && \
-    rm qt-everywhere-src-5.15.0.tar.xz
+    rm -rf qt-everywhere*
 
-ENV QTDIR /opt/Qt5.15.0
+ENV QTDIR /opt/Qt${QT_VERSION}
 ENV PATH "$QTDIR/bin:$PATH"
 
-RUN mkdir ~/ffmpeg_sources && \
-    cd ~/ffmpeg_sources && \
-    curl -O -L https://github.com/openssl/openssl/archive/OpenSSL_1_1_1g.tar.gz && \
-    tar -xf OpenSSL_1_1_1g.tar.gz && \
-    cd openssl-OpenSSL_1_1_1g && \
+RUN mkdir ~/openssl_sources && \
+    cd ~/openssl_sources && \
+    curl -O -L https://github.com/openssl/openssl/archive/OpenSSL_${OPENSSL_VERSION}.tar.gz && \
+    tar -xf OpenSSL_${OPENSSL_VERSION}.tar.gz && \
+    cd openssl-OpenSSL_${OPENSSL_VERSION} && \
     ./config --prefix="$HOME/ffmpeg_build" --openssldir="$HOME/ffmpeg_build" no-pinshared shared zlib && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
     # skip installing documentation
     make install_sw && \
-    rm -rf ~/openssl_build
+    cd .. && \
+    rm -rf ~/openssl_build ~/openssl_sources
 
-RUN cd ~/ffmpeg_sources && \
-    curl -O -L http://www.nasm.us/pub/nasm/releasebuilds/2.15.04/nasm-2.15.04.tar.bz2 && \
-    tar -xf nasm-2.15.04.tar.bz2 && cd nasm-2.15.04 && ./autogen.sh && \
+RUN mkdir ~/nasm_sources && \
+    cd ~/nasm_sources && \
+    curl -O -L http://www.nasm.us/pub/nasm/releasebuilds/${NASM_VERSION}/nasm-${NASM_VERSION}.tar.bz2 && \
+    tar -xf nasm-${NASM_VERSION}.tar.bz2 && cd nasm-${NASM_VERSION} && ./autogen.sh && \
     ./configure --prefix="$HOME/ffmpeg_build" --bindir="$HOME/bin" && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
-    make install
+    make install && \
+    cd .. && \
+    rm -rf ~/nasm_sources
 
-RUN cd ~/ffmpeg_sources && \
-    curl -O -L http://www.tortall.net/projects/yasm/releases/yasm-1.3.0.tar.gz && \
-    tar -xf yasm-1.3.0.tar.gz && \
-    cd yasm-1.3.0 && \
+RUN mkdir ~/yasm_sources && \
+    cd ~/yasm_sources && \
+    curl -O -L http://www.tortall.net/projects/yasm/releases/yasm-${YASM_VERSION}.tar.gz && \
+    tar -xf yasm-${YASM_VERSION}.tar.gz && \
+    cd yasm-${YASM_VERSION} && \
     ./configure --prefix="$HOME/ffmpeg_build" --bindir="$HOME/bin" && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
-    make install
+    make install && \
+    cd .. && \
+    rm -rf ~/yasm_sources
 
-RUN cd ~/ffmpeg_sources && \
-    git clone --depth 1 https://chromium.googlesource.com/webm/libvpx.git && \
+RUN mkdir ~/libvpx_sources && \
+    cd ~/libvpx_sources && \
+    git clone --depth 1 https://github.com/webmproject/libvpx.git && \
     cd libvpx && \
     ./configure --prefix="$HOME/ffmpeg_build" --disable-examples --disable-unit-tests --enable-vp9-highbitdepth --as=yasm --enable-pic --enable-shared && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
-    make install
+    make install && \
+    cd .. && \
+    rm -rf ~/libvpx_sources
 
-RUN cd ~/ffmpeg_sources && \
-    curl -O -L https://ffmpeg.org/releases/ffmpeg-4.3.2.tar.bz2 && \
-    tar -xf ffmpeg-4.3.2.tar.bz2 && \
-    cd ffmpeg-4.3.2 && \
+RUN mkdir ~/ffmpeg_sources && \
+    cd ~/ffmpeg_sources && \
+    curl -O -L https://ffmpeg.org/releases/ffmpeg-${FFMPEG_VERSION}.tar.bz2 && \
+    tar -xf ffmpeg-${FFMPEG_VERSION}.tar.bz2 && \
+    cd ffmpeg-${FFMPEG_VERSION} && \
     PATH=~/bin:$PATH && \
     PKG_CONFIG_PATH="$HOME/ffmpeg_build/lib/pkgconfig" ./configure --prefix="$HOME/ffmpeg_build" --extra-cflags="-I$HOME/ffmpeg_build/include" --extra-ldflags="-L$HOME/ffmpeg_build/lib" --enable-openssl --enable-libvpx --enable-shared --enable-pic --bindir="$HOME/bin" && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
     make install && \
     echo "/root/ffmpeg_build/lib/" >> /etc/ld.so.conf && \
     ldconfig && \
-    rm -rf ~/ffmpeg_sources
+    rm -rf ~/ffmpeg_sources && \
+    yum remove bzip2-devel -y
 
-RUN curl -O -L https://github.com/ccache/ccache/releases/download/v3.7.9/ccache-3.7.9.tar.gz && \
-    tar -xf ccache-3.7.9.tar.gz && \
-    cd ccache-3.7.9 && \
+RUN curl -O -L https://github.com/ccache/ccache/releases/download/v${CCACHE_VERSION}/ccache-${CCACHE_VERSION}.tar.gz && \
+    tar -xf ccache-${CCACHE_VERSION}.tar.gz && \
+    cd ccache-${CCACHE_VERSION} && \
     linux32 ./configure && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
-    make install
+    make install && \
+    cd .. && \
+    rm -rf ccache-${CCACHE_VERSION}.tar.gz
+
+# Git security vulnerability: https://github.blog/2022-04-12-git-security-vulnerability-announced
+RUN mkdir /io && \
+    git config --global --add safe.directory /io
 
 ENV PKG_CONFIG_PATH /usr/local/lib/pkgconfig:/root/ffmpeg_build/lib/pkgconfig
 ENV LDFLAGS -L/root/ffmpeg_build/lib
diff --git a/docker/manylinux2014/Dockerfile_i686 b/docker/manylinux2014/Dockerfile_i686
index 6a60a073..3b866874 100644
--- a/docker/manylinux2014/Dockerfile_i686
+++ b/docker/manylinux2014/Dockerfile_i686
@@ -1,26 +1,34 @@
 FROM quay.io/pypa/manylinux2014_i686:latest
 
+ARG CCACHE_VERSION=3.7.9
+ARG CMAKE_VERSION=3.17.0
+ARG FFMPEG_VERSION=4.4.1
+ARG NASM_VERSION=2.15.04
+ARG OPENSSL_VERSION=1_1_1m
+ARG QT_VERSION=5.15.0
+ARG YASM_VERSION=1.3.0
+
 RUN yum install bzip2-devel curl-devel zlib-devel xcb-util-renderutil-devel xcb-util-devel xcb-util-image-devel xcb-util-keysyms-devel xcb-util-wm-devel mesa-libGL-devel libxkbcommon-devel libxkbcommon-x11-devel libXi-devel freetype-devel -y
 
-RUN curl -O -L https://download.qt.io/official_releases/qt/5.15/5.15.0/single/qt-everywhere-src-5.15.0.tar.xz && \
-    tar -xf qt-everywhere-src-5.15.0.tar.xz && \
+RUN curl -O -L https://download.qt.io/official_releases/qt/5.15/${QT_VERSION}/single/qt-everywhere-src-${QT_VERSION}.tar.xz && \
+    tar -xf qt-everywhere-src-${QT_VERSION}.tar.xz && \
     cd qt-everywhere* && \
     export MAKEFLAGS=-j$(nproc) && \
-    ./configure -prefix /opt/Qt5.15.0 -release -opensource -confirm-license -qtnamespace QtOpenCVPython -xcb -xcb-xlib -bundled-xcb-xinput -no-openssl -no-dbus -skip qt3d -skip qtactiveqt -skip qtcanvas3d -skip qtconnectivity -skip qtdatavis3d -skip qtdoc -skip qtgamepad -skip qtgraphicaleffects -skip qtimageformats -skip qtlocation -skip qtmultimedia -skip qtpurchasing -skip qtqa -skip qtremoteobjects -skip qtrepotools -skip qtscript -skip qtscxml -skip qtsensors -skip qtserialbus -skip qtserialport -skip qtspeech -skip qttranslations -skip qtwayland -skip qtwebchannel -skip qtwebengine -skip qtwebsockets -skip qtwebview -skip xmlpatterns -skip declarative -make libs && \
+    ./configure -prefix /opt/Qt${QT_VERSION} -release -opensource -confirm-license -qtnamespace QtOpenCVPython -xcb -xcb-xlib -bundled-xcb-xinput -no-openssl -no-dbus -skip qt3d -skip qtactiveqt -skip qtcanvas3d -skip qtconnectivity -skip qtdatavis3d -skip qtdoc -skip qtgamepad -skip qtgraphicaleffects -skip qtimageformats -skip qtlocation -skip qtmultimedia -skip qtpurchasing -skip qtqa -skip qtremoteobjects -skip qtrepotools -skip qtscript -skip qtscxml -skip qtsensors -skip qtserialbus -skip qtserialport -skip qtspeech -skip qttranslations -skip qtwayland -skip qtwebchannel -skip qtwebengine -skip qtwebsockets -skip qtwebview -skip xmlpatterns -skip declarative -make libs && \
     make && \
     make install && \
     cd .. && \
-    rm -rf qt-everywhere-src-5.15.0 && \
-    rm qt-everywhere-src-5.15.0.tar.xz
+    rm -rf qt-everywhere-src-${QT_VERSION} && \
+    rm qt-everywhere-src-${QT_VERSION}.tar.xz
 
-ENV QTDIR /opt/Qt5.15.0
+ENV QTDIR /opt/Qt${QT_VERSION}
 ENV PATH "$QTDIR/bin:$PATH"
 
 RUN mkdir ~/ffmpeg_sources && \
     cd ~/ffmpeg_sources && \
-    curl -O -L https://github.com/openssl/openssl/archive/OpenSSL_1_1_1g.tar.gz && \
-    tar -xf OpenSSL_1_1_1g.tar.gz && \
-    cd openssl-OpenSSL_1_1_1g && \
+    curl -O -L https://github.com/openssl/openssl/archive/OpenSSL_${OPENSSL_VERSION}.tar.gz && \
+    tar -xf OpenSSL_${OPENSSL_VERSION}.tar.gz && \
+    cd openssl-OpenSSL_${OPENSSL_VERSION} && \
     # in i686, ./config detects x64 in i686 container without linux32
     # when run from "docker build"
     linux32 ./config --prefix="$HOME/ffmpeg_build" no-pinshared shared zlib && \
@@ -30,16 +38,16 @@ RUN mkdir ~/ffmpeg_sources && \
     rm -rf ~/openssl_build
 
 RUN cd ~/ffmpeg_sources && \
-    curl -O -L http://www.nasm.us/pub/nasm/releasebuilds/2.15.04/nasm-2.15.04.tar.bz2 && \
-    tar -xf nasm-2.15.04.tar.bz2 && cd nasm-2.15.04 && ./autogen.sh && \
+    curl -O -L http://www.nasm.us/pub/nasm/releasebuilds/${NASM_VERSION}/nasm-${NASM_VERSION}.tar.bz2 && \
+    tar -xf nasm-${NASM_VERSION}.tar.bz2 && cd nasm-${NASM_VERSION} && ./autogen.sh && \
     linux32 ./configure && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
     make install
 
 RUN cd ~/ffmpeg_sources && \
-    curl -O -L http://www.tortall.net/projects/yasm/releases/yasm-1.3.0.tar.gz && \
-    tar -xf yasm-1.3.0.tar.gz && \
-    cd yasm-1.3.0 && \
+    curl -O -L http://www.tortall.net/projects/yasm/releases/yasm-${YASM_VERSION}.tar.gz && \
+    tar -xf yasm-${YASM_VERSION}.tar.gz && \
+    cd yasm-${YASM_VERSION} && \
     linux32 ./configure && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
     make install
@@ -52,9 +60,9 @@ RUN cd ~/ffmpeg_sources && \
     make install
 
 RUN cd ~/ffmpeg_sources && \
-    curl -O -L https://ffmpeg.org/releases/ffmpeg-4.3.2.tar.bz2 && \
-    tar -xf ffmpeg-4.3.2.tar.bz2 && \
-    cd ffmpeg-4.3.2 && \
+    curl -O -L https://ffmpeg.org/releases/ffmpeg-${FFMPEG_VERSION}.tar.bz2 && \
+    tar -xf ffmpeg-${FFMPEG_VERSION}.tar.bz2 && \
+    cd ffmpeg-${FFMPEG_VERSION} && \
     PATH=~/bin:$PATH && \
     PKG_CONFIG_PATH="$HOME/ffmpeg_build/lib/pkgconfig" linux32 ./configure --prefix="$HOME/ffmpeg_build" --extra-cflags="-I$HOME/ffmpeg_build/include" --extra-ldflags="-L$HOME/ffmpeg_build/lib" --enable-openssl --enable-libvpx --enable-shared --enable-pic --bindir="$HOME/bin" && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
@@ -63,22 +71,22 @@ RUN cd ~/ffmpeg_sources && \
     ldconfig && \
     rm -rf ~/ffmpeg_sources
 
-RUN curl -O -L https://github.com/ccache/ccache/releases/download/v3.7.9/ccache-3.7.9.tar.gz && \
-    tar -xf ccache-3.7.9.tar.gz && \
-    cd ccache-3.7.9 && \
+RUN curl -O -L https://github.com/ccache/ccache/releases/download/v${CCACHE_VERSION}/ccache-${CCACHE_VERSION}.tar.gz && \
+    tar -xf ccache-${CCACHE_VERSION}.tar.gz && \
+    cd ccache-${CCACHE_VERSION} && \
     linux32 ./configure && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
     make install
 
-RUN curl -O -L https://github.com/Kitware/CMake/releases/download/v3.17.0/cmake-3.17.0.tar.gz && \
-    tar -xf cmake-3.17.0.tar.gz && \
-    cd cmake-3.17.0 && \
+RUN curl -O -L https://github.com/Kitware/CMake/releases/download/v${CMAKE_VERSION}/cmake-${CMAKE_VERSION}.tar.gz && \
+    tar -xf cmake-${CMAKE_VERSION}.tar.gz && \
+    cd cmake-${CMAKE_VERSION} && \
     export MAKEFLAGS=-j$(getconf _NPROCESSORS_ONLN) && \
     ./configure --system-curl && \
     make && \
     make install && \
     cd .. && \
-    rm -rf cmake-3.17.0*
+    rm -rf cmake-${CMAKE_VERSION}*
 
 ENV PKG_CONFIG_PATH /usr/local/lib/pkgconfig:/root/ffmpeg_build/lib/pkgconfig
 ENV LDFLAGS -L/root/ffmpeg_build/lib
diff --git a/docker/manylinux2014/Dockerfile_x86_64 b/docker/manylinux2014/Dockerfile_x86_64
index 49622378..13325756 100644
--- a/docker/manylinux2014/Dockerfile_x86_64
+++ b/docker/manylinux2014/Dockerfile_x86_64
@@ -1,65 +1,118 @@
 FROM quay.io/pypa/manylinux2014_x86_64:latest
 
-RUN yum install bzip2-devel curl-devel zlib-devel xcb-util-renderutil-devel xcb-util-devel xcb-util-image-devel xcb-util-keysyms-devel xcb-util-wm-devel mesa-libGL-devel libxkbcommon-devel libxkbcommon-x11-devel libXi-devel freetype-devel -y
+ARG FFMPEG_VERSION=4.4.1
+ARG FREETYPE_VERSION=2.12.1
+ARG LIBPNG_VERSION=1.6.37
+ARG NASM_VERSION=2.15.04
+ARG OPENSSL_VERSION=1_1_1o
+ARG QT_VERSION=5.15.0
+ARG YASM_VERSION=1.3.0
 
-RUN curl -O -L https://download.qt.io/official_releases/qt/5.15/5.15.0/single/qt-everywhere-src-5.15.0.tar.xz && \
-    tar -xf qt-everywhere-src-5.15.0.tar.xz && \
-    cd qt-everywhere* && \
+ENV LD_LIBRARY_PATH /usr/local/lib:$LD_LIBRARY_PATH
+
+# epel-release need for aarch64 to get openblas packages
+RUN yum install bzip2-devel curl-devel zlib-devel xcb-util-renderutil-devel xcb-util-devel xcb-util-image-devel xcb-util-keysyms-devel xcb-util-wm-devel mesa-libGL-devel libxkbcommon-devel libxkbcommon-x11-devel libXi-devel lapack-devel epel-release -y && \
+    yum install openblas-devel -y && \
+    cp /usr/include/lapacke/lapacke*.h /usr/include/ && \
+    curl https://raw.githubusercontent.com/xianyi/OpenBLAS/v0.3.3/cblas.h -o /usr/include/cblas.h && \
+    # libpng will be built from source
+    yum remove libpng -y
+
+RUN mkdir ~/libpng_sources && \
+    cd ~/libpng_sources && \
+    curl -O -L https://download.sourceforge.net/libpng/libpng-${LIBPNG_VERSION}.tar.gz && \
+    tar -xf libpng-${LIBPNG_VERSION}.tar.gz && \
+    cd libpng-${LIBPNG_VERSION} && \
+    ./configure --prefix=/usr/local && \
+    make && \
+    make install && \
+    cd .. && \
+    rm -rf ~/libpng_sources
+
+RUN mkdir ~/freetype_sources && \
+    cd ~/freetype_sources && \
+    curl -O -L https://download.savannah.gnu.org/releases/freetype/freetype-${FREETYPE_VERSION}.tar.gz && \
+    tar -xf freetype-${FREETYPE_VERSION}.tar.gz && \
+    cd freetype-${FREETYPE_VERSION} && \
+    ./configure --prefix="$HOME/ffmpeg_build" --enable-freetype-config && \
+    make && \
+    make install && \
+    cd .. && \
+    rm -rf ~/freetype_sources
+
+RUN curl -O -L https://download.qt.io/official_releases/qt/5.15/${QT_VERSION}/single/qt-everywhere-src-${QT_VERSION}.tar.xz && \
+    tar -xf qt-everywhere-src-${QT_VERSION}.tar.xz && \
+    cd qt-everywhere-src-${QT_VERSION} && \
     export MAKEFLAGS=-j$(nproc) && \
-    ./configure -prefix /opt/Qt5.15.0 -release -opensource -confirm-license -qtnamespace QtOpenCVPython -xcb -xcb-xlib -bundled-xcb-xinput -no-openssl -no-dbus -skip qt3d -skip qtactiveqt -skip qtcanvas3d -skip qtconnectivity -skip qtdatavis3d -skip qtdoc -skip qtgamepad -skip qtgraphicaleffects -skip qtimageformats -skip qtlocation -skip qtmultimedia -skip qtpurchasing -skip qtqa -skip qtremoteobjects -skip qtrepotools -skip qtscript -skip qtscxml -skip qtsensors -skip qtserialbus -skip qtserialport -skip qtspeech -skip qttranslations -skip qtwayland -skip qtwebchannel -skip qtwebengine -skip qtwebsockets -skip qtwebview -skip xmlpatterns -skip declarative -make libs && \
+    ./configure -prefix /opt/Qt${QT_VERSION} -release -opensource -confirm-license -qtnamespace QtOpenCVPython -xcb -xcb-xlib -bundled-xcb-xinput -no-openssl -no-dbus -skip qt3d -skip qtactiveqt -skip qtcanvas3d -skip qtconnectivity -skip qtdatavis3d -skip qtdoc -skip qtgamepad -skip qtgraphicaleffects -skip qtimageformats -skip qtlocation -skip qtmultimedia -skip qtpurchasing -skip qtqa -skip qtremoteobjects -skip qtrepotools -skip qtscript -skip qtscxml -skip qtsensors -skip qtserialbus -skip qtserialport -skip qtspeech -skip qttranslations -skip qtwayland -skip qtwebchannel -skip qtwebengine -skip qtwebsockets -skip qtwebview -skip xmlpatterns -skip declarative -make libs && \
     make && \
     make install && \
     cd .. && \
-    rm -rf qt-everywhere-src-5.15.0 && \
-    rm qt-everywhere-src-5.15.0.tar.xz
+    rm -rf qt-everywhere*
 
-ENV QTDIR /opt/Qt5.15.0
+ENV QTDIR /opt/Qt${QT_VERSION}
 ENV PATH "$QTDIR/bin:$PATH"
 
-RUN mkdir ~/ffmpeg_sources && \
-    cd ~/ffmpeg_sources && \
-    curl -O -L https://github.com/openssl/openssl/archive/OpenSSL_1_1_1g.tar.gz && \
-    tar -xf OpenSSL_1_1_1g.tar.gz && \
-    cd openssl-OpenSSL_1_1_1g && \
+RUN mkdir ~/openssl_sources && \
+    cd ~/openssl_sources && \
+    curl -O -L https://github.com/openssl/openssl/archive/OpenSSL_${OPENSSL_VERSION}.tar.gz && \
+    tar -xf OpenSSL_${OPENSSL_VERSION}.tar.gz && \
+    cd openssl-OpenSSL_${OPENSSL_VERSION} && \
     ./config --prefix="$HOME/ffmpeg_build" --openssldir="$HOME/ffmpeg_build" no-pinshared shared zlib && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
     # skip installing documentation
     make install_sw && \
-    rm -rf ~/openssl_build
+    cd .. && \
+    rm -rf ~/openssl_build ~/openssl_sources
 
-RUN cd ~/ffmpeg_sources && \
-    curl -O -L http://www.nasm.us/pub/nasm/releasebuilds/2.15.04/nasm-2.15.04.tar.bz2 && \
-    tar -xf nasm-2.15.04.tar.bz2 && cd nasm-2.15.04 && ./autogen.sh && \
+RUN mkdir ~/nasm_sources && \
+    cd ~/nasm_sources && \
+    curl -O -L http://www.nasm.us/pub/nasm/releasebuilds/${NASM_VERSION}/nasm-${NASM_VERSION}.tar.bz2 && \
+    tar -xf nasm-${NASM_VERSION}.tar.bz2 && cd nasm-${NASM_VERSION} && ./autogen.sh && \
     ./configure --prefix="$HOME/ffmpeg_build" --bindir="$HOME/bin" && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
-    make install
+    make install && \
+    cd .. && \
+    rm -rf ~/nasm_sources
 
-RUN cd ~/ffmpeg_sources && \
-    curl -O -L http://www.tortall.net/projects/yasm/releases/yasm-1.3.0.tar.gz && \
-    tar -xf yasm-1.3.0.tar.gz && \
-    cd yasm-1.3.0 && \
+RUN mkdir ~/yasm_sources && \
+    cd ~/yasm_sources && \
+    curl -O -L http://www.tortall.net/projects/yasm/releases/yasm-${YASM_VERSION}.tar.gz && \
+    tar -xf yasm-${YASM_VERSION}.tar.gz && \
+    cd yasm-${YASM_VERSION} && \
     ./configure --prefix="$HOME/ffmpeg_build" --bindir="$HOME/bin" && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
-    make install
+    make install && \
+    cd .. && \
+    rm -rf ~/yasm_sources
 
-RUN cd ~/ffmpeg_sources && \
+RUN mkdir ~/libvpx_sources && \
+    cd ~/libvpx_sources && \
     git clone --depth 1 https://chromium.googlesource.com/webm/libvpx.git && \
     cd libvpx && \
     ./configure --prefix="$HOME/ffmpeg_build" --disable-examples --disable-unit-tests --enable-vp9-highbitdepth --as=yasm --enable-pic --enable-shared && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
-    make install
+    make install && \
+    cd .. && \
+    rm -rf ~/libvpx_sources
 
-RUN cd ~/ffmpeg_sources && \
-    curl -O -L https://ffmpeg.org/releases/ffmpeg-4.3.2.tar.bz2 && \
-    tar -xf ffmpeg-4.3.2.tar.bz2 && \
-    cd ffmpeg-4.3.2 && \
+RUN mkdir ~/ffmpeg_sources && \
+    cd ~/ffmpeg_sources && \
+    curl -O -L https://ffmpeg.org/releases/ffmpeg-${FFMPEG_VERSION}.tar.bz2 && \
+    tar -xf ffmpeg-${FFMPEG_VERSION}.tar.bz2 && \
+    cd ffmpeg-${FFMPEG_VERSION} && \
     PATH=~/bin:$PATH && \
     PKG_CONFIG_PATH="$HOME/ffmpeg_build/lib/pkgconfig" ./configure --prefix="$HOME/ffmpeg_build" --extra-cflags="-I$HOME/ffmpeg_build/include" --extra-ldflags="-L$HOME/ffmpeg_build/lib" --enable-openssl --enable-libvpx --enable-shared --enable-pic --bindir="$HOME/bin" && \
     make -j$(getconf _NPROCESSORS_ONLN) && \
     make install && \
     echo "/root/ffmpeg_build/lib/" >> /etc/ld.so.conf && \
     ldconfig && \
-    rm -rf ~/ffmpeg_sources
+    rm -rf ~/ffmpeg_sources && \
+    yum remove bzip2-devel -y
+
+# Git security vulnerability: https://github.blog/2022-04-12-git-security-vulnerability-announced
+RUN mkdir /io && \
+    git config --global --add safe.directory /io
 
 ENV PKG_CONFIG_PATH /usr/local/lib/pkgconfig:/root/ffmpeg_build/lib/pkgconfig
 ENV LDFLAGS -L/root/ffmpeg_build/lib
diff --git a/opencv b/opencv
index 39c33341..a3d08823 160000
--- a/opencv
+++ b/opencv
@@ -1 +1 @@
-Subproject commit 39c3334147ec02761b117f180c9c4518be18d1fa
+Subproject commit a3d088231745d147681d90579ef6e5380d7e5cb5
diff --git a/opencv_contrib b/opencv_contrib
index 2bc3e1a1..0eda296f 160000
--- a/opencv_contrib
+++ b/opencv_contrib
@@ -1 +1 @@
-Subproject commit 2bc3e1a169afd2675ef68221176f32cc0ea5427a
+Subproject commit 0eda296f4038ae058d76e2d828da8d0e7991cf85
diff --git a/opencv_extra b/opencv_extra
index 822ee112..5bad5827 160000
--- a/opencv_extra
+++ b/opencv_extra
@@ -1 +1 @@
-Subproject commit 822ee11240b969e98e20546663bc481a5e7089cc
+Subproject commit 5bad58277b230294a76a5204d5a476db2c9b2132
diff --git a/patch_auditwheel_whitelist.py b/patch_auditwheel_whitelist.py
index d0cbf5b2..b32da17a 100644
--- a/patch_auditwheel_whitelist.py
+++ b/patch_auditwheel_whitelist.py
@@ -5,12 +5,11 @@
 
 policies = None
 
-with open(join(dirname(abspath(policy.__file__)), "policy.json")) as f:
+with open(join(dirname(abspath(policy.__file__)), "manylinux-policy.json")) as f:
     policies = json.load(f)
 
 for p in policies:
-    if p["name"] == "manylinux2014":
-        p["lib_whitelist"].append("libxcb.so.1")
+    p["lib_whitelist"].append("libxcb.so.1")
 
-with open(join(dirname(abspath(policy.__file__)), "policy.json"), "w") as f:
+with open(join(dirname(abspath(policy.__file__)), "manylinux-policy.json"), "w") as f:
     f.write(json.dumps(policies))
diff --git a/pyproject.toml b/pyproject.toml
index 6aaab1d3..ff535e86 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,7 @@
 [build-system]
 requires = [
-  "setuptools", "wheel", "scikit-build", "cmake", "pip",
+  "setuptools==59.2.0", "wheel==0.37.0", "cmake>=3.1", "pip",
+  "scikit-build>=0.13.2",
   "numpy==1.13.3; python_version=='3.6' and platform_machine != 'aarch64' and platform_machine != 'arm64'",
   "numpy==1.14.5; python_version=='3.7' and platform_machine != 'aarch64' and platform_machine != 'arm64'",
   "numpy==1.17.3; python_version=='3.8' and platform_machine != 'aarch64' and platform_machine != 'arm64'",
diff --git a/setup.py b/setup.py
index 1b1f59c7..5f74ff2a 100644
--- a/setup.py
+++ b/setup.py
@@ -22,26 +22,15 @@ def main():
     build_headless = get_build_env_var_by_name("headless")
     build_java = "ON" if get_build_env_var_by_name("java") else "OFF"
 
-    if sys.version_info[:2] >= (3, 6):
-        minimum_supported_numpy = "1.13.3"
-    if sys.version_info[:2] >= (3, 7):
-        minimum_supported_numpy = "1.14.5"
-    if sys.version_info[:2] >= (3, 8):
-        minimum_supported_numpy = "1.17.3"
-    if sys.version_info[:2] >= (3, 9):
-        minimum_supported_numpy = "1.19.3"
-    if sys.version_info[:2] >= (3, 10):
-        minimum_supported_numpy = "1.21.2"
-
-    # linux arm64 is a special case
-    if sys.platform.startswith("linux") and sys.version_info[:2] >= (3, 6) and platform.machine() == "aarch64":
-        minimum_supported_numpy = "1.19.3"
-
-    # macos arm64 is a special case
-    if sys.platform == "darwin" and sys.version_info[:2] >= (3, 6) and platform.machine() == "arm64":
-        minimum_supported_numpy = "1.21.0"
-
-    numpy_version = "numpy>=%s" % minimum_supported_numpy
+    install_requires = [
+        'numpy>=1.13.3; python_version<"3.7"',
+        'numpy>=1.14.5; python_version>="3.7"',
+        'numpy>=1.17.3; python_version>="3.8"',
+        'numpy>=1.19.3; python_version>="3.9"',
+        'numpy>=1.21.2; python_version>="3.10"',
+        'numpy>=1.19.3; python_version>="3.6" and platform_system=="Linux" and platform_machine=="aarch64"',
+        'numpy>=1.21.2; python_version>="3.6" and platform_system=="Darwin" and platform_machine=="arm64"',
+    ]
 
     python_version = cmaker.CMaker.get_python_version()
     python_lib_path = cmaker.CMaker.get_python_library(python_version).replace(
@@ -71,7 +60,7 @@ def main():
     )
 
     # https://stackoverflow.com/questions/1405913/python-32bit-or-64bit-mode
-    x64 = sys.maxsize > 2 ** 32
+    is64 = sys.maxsize > 2 ** 32
 
     package_name = "opencv-python"
 
@@ -99,7 +88,7 @@ def main():
     # Path regexes with forward slashes relative to CMake install dir.
     rearrange_cmake_output_data = {
         "cv2": (
-            [r"bin/opencv_videoio_ffmpeg\d{3}%s\.dll" % ("_64" if x64 else "")]
+            [r"bin/opencv_ffmpeg\d{3,4}%s\.dll" % ("_64" if is64 else "")]
             if os.name == "nt"
             else []
         )
@@ -108,8 +97,8 @@ def main():
         # Naming conventions vary so widely between versions and OSes
         # had to give up on checking them.
         [
-            "python/cv2/python-%s.%s/cv2[^/]*%s"
-            % (sys.version_info[0], sys.version_info[1], re.escape(sysconfig.get_config_var("EXT_SUFFIX")))
+            r"python/cv2/python-%s/cv2.*"
+            % (sys.version_info[0])
         ]
         +
         [
@@ -120,19 +109,7 @@ def main():
             r"python/cv2/.*config.*.py"
         ],
         "cv2.data": [  # OPENCV_OTHER_INSTALL_PATH
-            ("etc" if os.name == "nt" else "share/opencv4") + r"/haarcascades/.*\.xml"
-        ],
-        "cv2.gapi": [
-            "python/cv2" + r"/gapi/.*\.py"
-        ],
-        "cv2.mat_wrapper": [
-            "python/cv2" + r"/mat_wrapper/.*\.py"
-        ],
-        "cv2.misc": [
-            "python/cv2" + r"/misc/.*\.py"
-        ],
-        "cv2.utils": [
-            "python/cv2" + r"/utils/.*\.py"
+            ("etc" if os.name == "nt" else "share/OpenCV") + r"/haarcascades/.*\.xml"
         ],
     }
 
@@ -141,7 +118,7 @@ def main():
     files_outside_package_dir = {"cv2": ["LICENSE.txt", "LICENSE-3RD-PARTY.txt"]}
 
     ci_cmake_generator = (
-        ["-G", "Visual Studio 14" + (" Win64" if x64 else "")]
+        ["-G", "Visual Studio 14" + (" Win64" if is64 else "")]
         if os.name == "nt"
         else ["-G", "Unix Makefiles"]
     )
@@ -170,11 +147,19 @@ def main():
             "-DBUILD_TESTS=OFF",
             "-DBUILD_PERF_TESTS=OFF",
             "-DBUILD_DOCS=OFF",
+            "-DPYTHON3_LIMITED_API=ON",
+            "-DBUILD_OPENEXR=ON",
         ]
         + (
+            # CMake flags for windows/arm64 build
+            ["-DCMAKE_GENERATOR_PLATFORM=ARM64",
+             # Emulated cmake requires following flags to correctly detect
+             # target architecture for windows/arm64 build
+             "-DOPENCV_WORKAROUND_CMAKE_20989=ON",
+             "-DCMAKE_SYSTEM_PROCESSOR=ARM64"]
+            if platform.machine() == "ARM64" and sys.platform == "win32"
             # If it is not defined 'linker flags: /machine:X86' on Windows x64
-            ["-DCMAKE_GENERATOR_PLATFORM=x64"]
-            if x64 and sys.platform == "win32"
+            else ["-DCMAKE_GENERATOR_PLATFORM=x64"] if is64 and sys.platform == "win32"
             else []
           )
         + (
@@ -194,7 +179,7 @@ def main():
                 "-DWITH_MSMF=OFF"
             )  # see: https://github.com/skvark/opencv-python/issues/263
 
-    if sys.platform.startswith("linux") and not x64 and "bdist_wheel" in sys.argv:
+    if sys.platform.startswith("linux") and not is64 and "bdist_wheel" in sys.argv:
         subprocess.check_call("patch -p0 < patches/patchOpenEXR", shell=True)
 
     # OS-specific components during CI builds
@@ -257,7 +242,7 @@ def main():
         package_data=package_data,
         maintainer="Olli-Pekka Heinisuo",
         ext_modules=EmptyListWithLength(),
-        install_requires=numpy_version,
+        install_requires=install_requires,
         python_requires=">=3.6",
         classifiers=[
             "Development Status :: 5 - Production/Stable",
@@ -378,10 +363,10 @@ def _classify_installed_files_override(
         print("Copying files from CMake output")
 
         # add lines from the old __init__.py file to the config file
-        with open('scripts/__init__.py', 'r') as custom_init:
+        with open(os.path.join(os.path.dirname(os.path.abspath(__file__)), 'scripts', '__init__.py'), 'r') as custom_init:
             custom_init_data = custom_init.read()
-        with open('%spython/cv2/config-%s.%s.py'
-        % (cmake_install_dir, sys.version_info[0], sys.version_info[1]), 'w') as opencv_init_config:
+        with open('%spython/cv2/config-%s.py'
+        % (cmake_install_dir, sys.version_info[0]), 'w') as opencv_init_config:
             opencv_init_config.write(custom_init_data)
 
         for package_name, relpaths_re in cls.package_paths_re.items():
@@ -405,7 +390,8 @@ def _classify_installed_files_override(
                     final_install_relpaths.append(new_install_relpath)
                     del m, fslash_relpath, new_install_relpath
                 else:
-                    if not found:
+                    # gapi can be missed if ADE was not downloaded (network issue)
+                    if not found and "gapi" not in relpath_re:
                         raise Exception("Not found: '%s'" % relpath_re)
                 del r, found
 
@@ -444,7 +430,7 @@ def _classify_installed_files_override(
             data_files,
             # To get around a check that prepends source dir to paths and breaks package detection code.
             cmake_source_dir="",
-            cmake_install_dir=cmake_install_reldir,
+            _cmake_install_dir=cmake_install_reldir,
         )
 
 
diff --git a/tests/pylintrc b/tests/pylintrc
new file mode 100644
index 00000000..a3892018
--- /dev/null
+++ b/tests/pylintrc
@@ -0,0 +1,12 @@
+# Source: opencv/platforms/scripts/pylintrc
+
+[MESSAGES CONTROL]
+
+# Disable all to choose the Tests one by one
+disable=all
+
+# Tests
+enable=bad-indentation,       # Used when an unexpected number of indentation’s tabulations or spaces has been found.
+       mixed-indentation,     # Used when there are some mixed tabs and spaces in a module.
+       unnecessary-semicolon, # Used when a statement is ended by a semi-colon (”;”), which isn’t necessary.
+       unused-variable        # Used when a variable is defined but not used. (Use _var to ignore var).
diff --git a/travis_config.sh b/travis_config.sh
index 937e5a2d..366d35ad 100644
--- a/travis_config.sh
+++ b/travis_config.sh
@@ -12,18 +12,18 @@ function build_wheel {
 
 function bdist_wheel_cmd {
     # copied from multibuild's common_utils.sh
-    # add osx deployment target so it doesnt default to 10.6
+    # add osx deployment target so it doesn't default to 10.6
     local abs_wheelhouse=$1
-    CI_BUILD=1 pip wheel --verbose --wheel-dir="$PWD/dist" . $BDIST_PARAMS
+    # install all required packages in pyproject.toml, because bdist_wheel does not do it
+    python${PYTHON_VERSION} -m pip install toml && python${PYTHON_VERSION} -c 'import toml; c = toml.load("pyproject.toml"); print("\n".join(c["build-system"]["requires"]))' | python${PYTHON_VERSION} -m pip install -r /dev/stdin
+    CI_BUILD=1 python${PYTHON_VERSION} setup.py bdist_wheel --py-limited-api=cp36 -v
     cp dist/*.whl $abs_wheelhouse
     if [ -z "$IS_OSX" ]; then
-      TOOLS_PATH=/opt/_internal/tools
-      /opt/python/cp37-cp37m/bin/python -m venv $TOOLS_PATH
+      # this path can be changed in the latest manylinux image
+      TOOLS_PATH=/opt/_internal/pipx/venvs/auditwheel
+      /opt/python/cp39-cp39/bin/python -m venv $TOOLS_PATH
       source $TOOLS_PATH/bin/activate
-      python$PYTHON_VERSION -m pip install auditwheel==3.2.0
-      python$PYTHON_VERSION patch_auditwheel_whitelist.py
-      # to avoid issues with numpy wheels
-      rm /io/wheelhouse/numpy*
+      python patch_auditwheel_whitelist.py
       deactivate
     fi
     if [ -n "$USE_CCACHE" -a -z "$BREW_BOOTSTRAP_MODE" ]; then ccache -s; fi
@@ -50,7 +50,7 @@ if [ -n "$IS_OSX" ]; then
     function generate_ffmpeg_formula {
         local FF="ffmpeg"
         local LFF="ffmpeg_opencv"
-        local FF_FORMULA; FF_FORMULA=$(brew formula "$FF")
+        local FF_FORMULA; FF_FORMULA=$(brew formula "${FF}${FFMPEG_FORMULA_VERSION}")
         local LFF_FORMULA; LFF_FORMULA="$(dirname "$FF_FORMULA")/${LFF}.rb"
 
         local REGENERATE
@@ -70,8 +70,9 @@ if [ -n "$IS_OSX" ]; then
         if [ -n "$REGENERATE" ]; then
             echo "Regenerating custom ffmpeg formula"
             # Bottle block syntax: https://docs.brew.sh/Bottles#bottle-dsl-domain-specific-language
+            # FfmpegAT4 is a class in ffmpeg@4 formula
             perl -wpe 'BEGIN {our ($found_blank, $bottle_block);}
-                if (/(^class )(Ffmpeg)(\s.*)/) {$_=$1.$2."Opencv".$3."\n"; next;}
+                if (/(^class )(FfmpegAT4)(\s.*)/) {$_=$1."FfmpegOpencv".$3."\n"; next;}
                 if (!$found_blank && /^$/) {$_.="conflicts_with \"ffmpeg\"\n\n"; $found_blank=1; next;}
                 if (!$bottle_block && /^\s*bottle do$/) { $bottle_block=1; next; }
                 if ($bottle_block) { if (/^\s*end\s*$/) { $bottle_block=0} elsif (/^\s*sha256\s/) {$_=""} next; }
@@ -97,11 +98,6 @@ function pre_build {
 
   if [ -n "$IS_OSX" ]; then
     brew install lapack
-  else
-    # epel-release need for aarch64 to get openblas packages
-    yum install -y lapack-devel epel-release && yum install -y openblas-devel
-    cp /usr/include/lapacke/lapacke*.h /usr/include/
-    curl https://raw.githubusercontent.com/xianyi/OpenBLAS/v0.3.3/cblas.h -o /usr/include/cblas.h
   fi
 
   if [ -n "$IS_OSX" ]; then
@@ -111,34 +107,14 @@ function pre_build {
     CACHE_STAGE=
     export HOMEBREW_NO_AUTO_UPDATE=1
 
-    #after the cache stage, all bottles and Homebrew metadata should be already cached locally
-    # if [ -n "$CACHE_STAGE" ]; then
-    #     brew update
-    #     generate_ffmpeg_formula
-    #     brew_add_local_bottles
-    # fi
-
     echo 'Installing FFmpeg'
 
-    # if [ -n "$CACHE_STAGE" ]; then
-    #     brew_install_and_cache_within_time_limit ffmpeg_opencv || { [ $? -gt 1 ] && return 2 || return 0; }
-    # else
-        brew update
-        generate_ffmpeg_formula
-        brew_add_local_bottles
-        # brew unlink python@2
-        brew install --build-bottle ffmpeg_opencv
-    # fi
-
-    # echo 'Installing qt5'
-
-    # if [ -n "$CACHE_STAGE" ]; then
-    #    echo "Qt5 has bottle, no caching needed"
-    # else
-    #    brew switch qt 5.13.2
-    #    brew pin qt
-    #    export PATH="/usr/local/opt/qt/bin:$PATH"
-    # fi
+    brew update
+    generate_ffmpeg_formula
+    brew_add_local_bottles
+    brew install --build-bottle ffmpeg_opencv
+    # It needs when we use not the latest ffmpeg formula
+    brew link ffmpeg_opencv
 
     if [ -n "$CACHE_STAGE" ]; then
         brew_go_bootstrap_mode 0
@@ -160,37 +136,37 @@ function run_tests {
 
     PYTHON=python$PYTHON_VERSION
 
-    if [ -n "$IS_OSX" ]; then
-      echo "Running for OS X"
-
-      cd ../tests
-      $PYTHON get_build_info.py
-
-      cd ../opencv/
-      export OPENCV_TEST_DATA_PATH=../opencv_extra/testdata
-    else
-      echo "Running for linux"
-
-      if [ $PYTHON == "python3.6" ]; then
-        $PYTHON -m pip install -U numpy==1.19.4
-      fi
-      cd /io/tests
-      $PYTHON get_build_info.py
+    echo "Running for linux"
 
-      cd /io/opencv
-      export OPENCV_TEST_DATA_PATH=/io/opencv_extra/testdata
+    if [ $PYTHON == "python3.6" ]; then
+      $PYTHON -m pip install -U numpy==1.19.4
     fi
+    cd /io/tests
+    $PYTHON get_build_info.py
+
+    cd /io/opencv
+    export OPENCV_TEST_DATA_PATH=/io/opencv_extra/testdata
 
     test_wheels
+    pylint_test
 }
 
 function test_wheels {
 
-    echo "Starting tests..."
+    echo "Starting OpenCV tests..."
 
     #Test package
     $PYTHON modules/python/test/test.py -v --repo .
 }
 
+function pylint_test {
+
+    echo "Starting Pylint tests..."
+
+    $PYTHON -m pip install pylint==2.12.2
+    cd /io/tests
+    $PYTHON -m pylint /io/opencv/samples/python/squares.py
+}
+
 export PS4='+(${BASH_SOURCE}:${LINENO}): ${FUNCNAME[0]:+${FUNCNAME[0]}(): }'
 set -x
diff --git a/travis_osx_brew_cache.sh b/travis_osx_brew_cache.sh
index 401265f2..1a2a1c6c 100644
--- a/travis_osx_brew_cache.sh
+++ b/travis_osx_brew_cache.sh
@@ -249,7 +249,7 @@ function _brew_install_and_cache_within_time_limit {
     for dep in $DEPS; do
         #TIME_LIMIT only has to be met if we'll be actually building the main project this iteration, i.e. after the "root" module installation
         #While we don't know that yet, we can make better use of Travis-given time with a laxer limit
-        #We still can't overrun TIME_HARD_LIMIT as that would't leave time to save the cache
+        #We still can't overrun TIME_HARD_LIMIT as that wouldn't leave time to save the cache
         _brew_install_and_cache_within_time_limit "$dep" $(((TIME_LIMIT+TIME_HARD_LIMIT)/2)) "$TIME_HARD_LIMIT" "$TIME_START" || return $?
     done