[FFmpeg-user] Re-encode single frame

[Roelof van Wyk]

Hi All



I need to do the following:



1.       Decode a H264 stream and identify a certain B frame/picture

2.       Perform some modifications to the frame

3.       Re-encode _only_ that frame and insert back into the original stream, without any modifications to the surrounding frames. I do not want to re-encode the entire stream



So if the input GOP is IBBPBBPBBP..., the output GOP must be IBBPB'PBBP...



Does the ffmpeg/libav API allow the encoder context to be initialized from the decoder context such that this can be done, and if so, can anybody provide me with some ideas or examples?



Thanks

Roelof