Merge pull request opencv#10144 from mshabunin:fix-videocapture-open-order

vpisarev · vpisarev · commit d59472bf4032 · 2017-11-23T12:50:25.000Z
diff --git a/modules/videoio/src/cap.cpp b/modules/videoio/src/cap.cpp
@@ -527,49 +527,35 @@ static Ptr<IVideoCapture> IVideoCapture_create(int index)
 }
 
 
-static Ptr<IVideoCapture> IVideoCapture_create(const String& filename)
+static Ptr<IVideoCapture> IVideoCapture_create(const String& filename, int apiPreference)
 {
-    int  domains[] =
-    {
-        CAP_ANY,
+    bool useAny = (apiPreference == CAP_ANY);
+    Ptr<IVideoCapture> capture;
 #ifdef HAVE_GPHOTO2
-        CAP_GPHOTO2,
-#endif
-#ifdef HAVE_MFX
-        CAP_INTEL_MFX,
-#endif
-        -1, -1
-    };
-
-    // try every possibly installed camera API
-    for (int i = 0; domains[i] >= 0; i++)
+    if (useAny || apiPreference == CAP_GPHOTO2)
     {
-        Ptr<IVideoCapture> capture;
-
-        switch (domains[i])
-        {
-        case CAP_ANY:
-            capture = createMotionJpegCapture(filename);
-            break;
-#ifdef HAVE_GPHOTO2
-        case CAP_GPHOTO2:
-            capture = createGPhoto2Capture(filename);
-            break;
+        capture = createGPhoto2Capture(filename);
+        if (capture && capture->isOpened())
+            return capture;
+    }
 #endif
 #ifdef HAVE_MFX
-        case CAP_INTEL_MFX:
-            capture = makePtr<VideoCapture_IntelMFX>(filename);
-            break;
+    if (useAny || apiPreference == CAP_INTEL_MFX)
+    {
+        capture = makePtr<VideoCapture_IntelMFX>(filename);
+        if (capture && capture->isOpened())
+            return capture;
+    }
 #endif
-        }
-
+    if (useAny || apiPreference == CAP_OPENCV_MJPEG)
+    {
+        capture = createMotionJpegCapture(filename);
         if (capture && capture->isOpened())
-        {
             return capture;
-        }
     }
-    // failed open a camera
-    return Ptr<IVideoCapture>();
+    if (capture && !capture->isOpened())
+        capture.release();
+    return capture;
 }
 
 static Ptr<IVideoWriter> IVideoWriter_create(const String& filename, int apiPreference, int _fourcc, double fps, Size frameSize, bool isColor)
@@ -625,7 +611,7 @@ bool VideoCapture::open(const String& filename, int apiPreference)
     CV_TRACE_FUNCTION();
 
     if (isOpened()) release();
-    icap = IVideoCapture_create(filename);
+    icap = IVideoCapture_create(filename, apiPreference);
     if (!icap.empty())
         return true;
 
diff --git a/modules/videoio/test/test_ffmpeg.cpp b/modules/videoio/test/test_ffmpeg.cpp
@@ -131,7 +131,7 @@ class CV_FFmpegWriteBigVideoTest : public cvtest::BaseTest
                     fps = 25;
                 }
 
-                VideoWriter writer(filename, tag, fps, frame_s);
+                VideoWriter writer(filename, CAP_FFMPEG, tag, fps, frame_s);
 
                 if (writer.isOpened() == false)
                 {
@@ -194,7 +194,7 @@ class CV_FFmpegReadImageTest : public cvtest::BaseTest
         try
         {
             string filename = ts->get_data_path() + "readwrite/ordinary.bmp";
-            VideoCapture cap(filename);
+            VideoCapture cap(filename, CAP_FFMPEG);
             Mat img0 = imread(filename, 1);
             Mat img, img_next;
             cap >> img;
@@ -242,7 +242,7 @@ class CreateVideoWriterInvoker :
             std::string fileName = tempfile(stream.str().c_str());
 
             files->operator[](i) = fileName;
-            writers->operator[](i) = new VideoWriter(fileName, VideoWriter::fourcc('X','V','I','D'), 25.0f, FrameSize);
+            writers->operator[](i) = new VideoWriter(fileName, CAP_FFMPEG, VideoWriter::fourcc('X','V','I','D'), 25.0f, FrameSize);
 
             CV_Assert(writers->operator[](i)->isOpened());
         }
@@ -325,7 +325,7 @@ class CreateVideoCaptureInvoker :
     {
         for (int i = range.start; i != range.end; ++i)
         {
-            readers->operator[](i) = new VideoCapture(files->operator[](i));
+            readers->operator[](i) = new VideoCapture(files->operator[](i), CAP_FFMPEG);
             CV_Assert(readers->operator[](i)->isOpened());
         }
     }

Original file line number	Diff line number	Diff line change
`@@ -131,7 +131,7 @@ class CV_FFmpegWriteBigVideoTest : public cvtest::BaseTest`
`131`	`131`	`fps = 25;`
`132`	`132`	`}`
`133`	`133`
`134`		`- VideoWriter writer(filename, tag, fps, frame_s);`
	`134`	`+ VideoWriter writer(filename, CAP_FFMPEG, tag, fps, frame_s);`
`135`	`135`
`136`	`136`	`if (writer.isOpened() == false)`
`137`	`137`	`{`
`@@ -194,7 +194,7 @@ class CV_FFmpegReadImageTest : public cvtest::BaseTest`
`194`	`194`	`try`
`195`	`195`	`{`
`196`	`196`	`string filename = ts->get_data_path() + "readwrite/ordinary.bmp";`
`197`		`- VideoCapture cap(filename);`
	`197`	`+ VideoCapture cap(filename, CAP_FFMPEG);`
`198`	`198`	`Mat img0 = imread(filename, 1);`
`199`	`199`	`Mat img, img_next;`
`200`	`200`	`cap >> img;`
`@@ -242,7 +242,7 @@ class CreateVideoWriterInvoker :`
`242`	`242`	`std::string fileName = tempfile(stream.str().c_str());`
`243`	`243`
`244`	`244`	`files->operator[](i) = fileName;`
`245`		`- writers->operator[](i) = new VideoWriter(fileName, VideoWriter::fourcc('X','V','I','D'), 25.0f, FrameSize);`
	`245`	`+ writers->operator[](i) = new VideoWriter(fileName, CAP_FFMPEG, VideoWriter::fourcc('X','V','I','D'), 25.0f, FrameSize);`
`246`	`246`
`247`	`247`	`CV_Assert(writers->operator[](i)->isOpened());`
`248`	`248`	`}`
`@@ -325,7 +325,7 @@ class CreateVideoCaptureInvoker :`
`325`	`325`	`{`
`326`	`326`	`for (int i = range.start; i != range.end; ++i)`
`327`	`327`	`{`
`328`		`- readers->operator[](i) = new VideoCapture(files->operator[](i));`
	`328`	`+ readers->operator[](i) = new VideoCapture(files->operator[](i), CAP_FFMPEG);`
`329`	`329`	`CV_Assert(readers->operator[](i)->isOpened());`
`330`	`330`	`}`
`331`	`331`	`}`