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Hardware Accelerated Decoding in Windows

Posted: Thu Jun 30, 2011 9:13 pm
by rh11
Hello Everyone,

We need hardware accelerated decoding for h.263,h.264 and other computationally intensive codecs. Is this support enabled in the builds? I looked at the documentation for ffmpeg, but could not find anything conclusive about hardware acceleration in Windows (more specifically, the use of DXVA). I am using Windows 7 and am trying to choose between Media Foundation and ffmpeg. I suspect that ffmpeg might only use hardware acceleration for playback (i.e. when it is rendering to a surface), but not for plain decoding and writing to a raw video file. It would be very helpful is someone could share their insights/experience about this.

Generally, when I run ffmplay from Windows command line, the CPU load (from Task Manager) remains below 10%. But, when I capture raw frames from an input video files, the CPU load goes up significantly (40-50% and at the end spikes to 100%)

Thank you very much in advance.

Regards.

Re: Hardware Accelerated Decoding in Windows

Posted: Wed Jul 06, 2011 2:07 am
by ramiro
ffmpeg/ffplay/ffprobe don't use dxva2 for decoding themselves. dxva2 returns a directx surface, and ffmpeg doesn't treat that output. it's only used if you write specific code to use it (like vlc does, by overwriting get_format and get_buffer before opening the decoder or something like that)