On Tue, Feb 13, 2018 at 6:57 AM, Alex P <ale...@avenview.com> wrote: > I think I've figured it out. When I use nv12 or yuv420p as the input and > output pixel format, I get x1 performance. If I use bgr24/rgb24 as the > input and yuv444p as the output, I get around x0.3. >
Looks like switching pixel formats highly impacts performance. It would be better for your capture card to output, for example, yuv444p. I can't tell from the specs if it can do that though. Careful selecting nv12 as format for output, my quick test showed that the final output was yuv420p. > In your testing James, what was the pixel format? I was testing yuv420p samples as that is what was available to me at the time. I have made a yuv444p using testsrc. My poor Thuban cannot decode this FFv1 at realtime and raw-video filesize is gigantic. So I made a lossless hevc yuv444p. Surprisingly (or maybe not) hevc_cuvid can't decode it! Again, my poor Thuban cannot decode real-time, but there's some hope: FFmpeg encoding speed was about 35-40 fps and hw-encoder utilization topped out at 40%. So there's still a lot of headroom in the hw-encoder. Rough theoretical calculation: I could get 100fps hw-encoding which is ~1.7X I got about the same speed for h264_nvenc lossless. I got similar results using a 3 second raw yuv444p video input file. If there are other pix_fmts you would like me to test, let me know. I'll do my best to try. _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".