[Libav-user] Problem with using libavcodec with AV_CODEC_ID_H264

[Alex Cohn]

On Sun, Feb 10, 2013 at 12:38 AM, Ashwin Chandra - SISA
<ashwin.c at sisa.samsung.com> wrote:
> 1. Just as a sanity check, to disable b-frames, I just set the max_bframes parameter to 0?
> 2. If GOP size is 1, wouldn't that always be I frames? No predictional ones?]

You probably missed the link yesterday:
http://libav-users.943685.n4.nabble.com/Libav-user-FFmpeg-x264-settings-for-zero-delay-encoding-tp4655209p4655212.html.

There is "preset" and "tune" options in ffmpeg, you can set them that way:

#include "opt.h"

av_opt_set(codecContex->priv_data, "preset", "ultrafast", 0);
av_opt_set(codecContex->priv_data, "tune", "zerolatency", 0);

where codecContex is AVCodecContext.

For other x264 options that isn't presented in ffmpeg you could use
"x264opts" option:

av_opt_set(codecContex->priv_data, "x264opts",
"no-mbtree:sliced-threads:sync-lookahead=0", 0);

Regarding P-frames, I thought you wanted to remove them, too.

Sincerely,
Alex