[Libav-user] Muxed audio and video streams are not synchronized.

[Carl Eugen Hoyos]

Talgorn François-Xavier <fxtalgorn-at-yahoo.fr at ...> writes:

> 2) The resulting image quality is poor, we can see macro 
> blocks covering the whole images (even in still parts of 
> the frames).

You do not show the initialization of the 
encoder you are using.
(Or do you?)

> rgb_pix->av_frame=YUVtoRGB(yuv_pix->av_frame, in_stream->codec);
> waterMark(rgb_pix->av_frame, in_stream->codec);
> yuv_pix->av_frame=RGBtoYUV(rgb_pix->av_frame, in_stream->codec);

Did you try the scale and the overlay filter?
They should be very fast (and you may not have to 
scale at all).

Carl Eugen