[FFmpeg-user] Replace dropped frames in H264

[Aviv Hurvitz]

Apologies that my question is hardly related to Ffmpeg. Just trying to tap
into the knowledge of the experts on this user group.

On Tue, Dec 18, 2018 at 10:32 PM Aviv Hurvitz <aviv.hurvitz at gmail.com>
wrote:

> I am dealing with a system that transfers H264 over the internet in the
> following way:
> We break the encoded stream into frames, then we send individual frames
> over the network, then we piece the stream back together.
>
> The problem is that due to inadequate network speed we sometimes drop
> frames out of the stream. When we piece the stream back together, it has
> gaps of course, which corrupts that group-of-frames, but what is worse -
> seeking by timestamp is incorrect.
>
> What I want to do is fill the dropped frames with some spacer that will
> ensure the video has the correct length and seeks by timestamp will work.
>
> I am willing to replace individual frames or even entire groups-of-frames
> to make the seeking work.
>
> The video is fixed rate 25 FPS, has no B frames, has I frames every second.
> I know exactly which frames were dropped.
> My question is: how do I make the spacer frames? Say, if a P frame was
> lost, would it make sense to duplicate the P frame that came before it to
> make a spacer?
>
>
>