[FFmpeg-devel] Raw Decoding Bug

C Chatterjee cchatterj at hotmail.com
Mon Jan 9 23:50:39 CET 2012



Copied a h.264 file to the link below.

http://www.mediafire.com/?0kwtdmeru4kshi1

I used FFMEG to decode to you with:
ffmpeg -y -i obx.264 -f rawvideo obff.yuv

The yuv file dropped one frame - the first frame.
I diagnosed the problem. The ist->pts is set to -8000 in init_input_streams().
The do_video_out() drops the first frame because vdelta=-2.

One way to fix this is to have a ist->first_pts set to ist->pts the very first time.
Then change get_sync_ipts() to return:
    return (double)(ist->pts - ist->first_pts - of->start_time)/AV_TIME_BASE;
instead of
    return (double)(ist->pts - of->start_time)/AV_TIME_BASE;

This fixes the problem of frame dropping but may break other encodings.

Ideas??

Chanchal
 		 	   		  


More information about the ffmpeg-devel mailing list