Problem with encoding about avcpp HOT 1 CLOSED

Uh... browser drop my anwer. In short: not an issue, just a WAD.

Some codecs has Delay in some amount of frames. Delay - major thing. In some cases Delay requires by performance optimization or by codec design itself (B-frames).

So, in some cases you should put some amount of packets to the codec before receive first decoded frame. Count of packets that sends to codec before first frame is a codec Delay. As a result, avcodec_receive_frame() can produce EAGAIN error for a some time.

Also, after input stream finished you must put some amount null packets to drain codecs and receive leftover frames. You should do it until EAGAIN (in my API: I do not put null packet to the codec, so it does not moves to flush state, basically it is an error) or AVERROR_EOF.

For more details see:

• https://www.ffmpeg.org/doxygen/3.1/group__lavc__encdec.html
• https://blogs.gentoo.org/lu_zero/2016/03/29/new-avcodec-api/

from avcpp.