high performance video output with Qt -

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i'm writing video player code decodes video raw ycbcr frames. fastest way output these through qt framework? want avoid copying data around images in hd format.

i afraid software color conversion qimage slow , later qimage again copied when drawing gui.

i have had @ qabstractvideosurface , have running code, cannot grasp how faster, since in videowidget example (http://idlebox.net/2010/apidocs/qt-everywhere-opensource-4.7.0.zip/multimedia-videowidget.html), rendering still done calling qpainter::drawimage qimage, has in rgb.

the preferred solution seems me have access hardware surface directly decode ycbcr or @ least directly rgb conversion (with libswscale) into. cannot see how (without using opengl, give me free scaling too, though).

one common solution use qgl widget texture mapping. application allocates texture buffer on first frame, call update texture in remaining frames. pure gl call, qt not supporting texture manipulation yet. qglwidget can used container.

decoding done using sse2. hope helps.


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