add buffer example

jcupitt · jcupitt · commit 5ed6c032e665 · 2019-06-23T23:14:23.000+01:00
diff --git a/example/buffer.lua b/example/buffer.lua
@@ -0,0 +1,20 @@
+#!/usr/bin/luajit
+
+-- load and save images to and from memory buffers
+
+local vips = require "vips"
+
+local f = io.open(arg[1], "rb")
+local content = f:read("*all")
+
+local im = vips.Image.new_from_buffer(content, "", {access = "sequential"})
+
+-- brighten 20%
+im = (im * 1.2):cast("uchar")
+
+-- print as mime jpg
+local buffer = im:write_to_buffer(".jpg", {Q = 90})
+print("Content-length: " .. #buffer)
+print("Content-type: image/jpeg")
+print("")
+print(buffer)
