[FFmpeg-user] an issue on decoding a mxf xavc long gop file.

Yufei He yhe at matrox.com
Wed Apr 10 01:24:37 EEST 2019

On 04/08/2019 02:03 PM, Carl Eugen Hoyos wrote:
> 2019-04-08 18:56 GMT+02:00, Yufei He <yhe at matrox.com>:
>> On 04/07/2019 05:37 PM, Carl Eugen Hoyos wrote:
>>> 2019-04-05 17:03 GMT+02:00, Yufei He <yhe at matrox.com>:
>>>> I use avctx->framerate in my codec.
>>> Why?
>>> I am not claiming that there is no bug (I opened a ticket)
>>> but I don't see why you need the value, even more so
>>> if there is not issue with the native decoder.
>> The chip needs frame rate to be initialized properly.
> Does that mean that only (strict) cfr is supported by the chip?
> Carl Eugen
Chip just needs frame rate to get initialized, it can go as fast as 

I have a question:

In line 809 of file ffmpeg_opt.c

             // avformat_find_stream_info() doesn't set this for us anymore.
             ist->dec_ctx->framerate = st->avg_frame_rate;

Why is avg_frame_rate assigned to  ist->dec_ctx->framerate ?
Why not st->r_frame_rate;



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