Reencoding while preserving original FPS

[vpenades]

Something I've tried several times with FFmpeg.AutoGen, and failed to do, is to be able to process a source file, while preserving as much from the original file as possible.

What I want to do is something like this:

ProcessFrames("source.mp4", "destination.mp4",  _singleFrameProcessor);

void _singleFrameProcessor(int width, int height, int stride, string pixelFormat, Byte[] pixels)
{
    // draw some text over the image, apply denoise filter, whatever.
}

And I would like to do so while preserving the original FPS and audio stream.

The example you have has a fixed 25 fps and it is not specified how to get the fps from the original video.

Also, I am not sure if setting the target FPS is the right approach, and what would be required is to set AVFrame.pts, AVFrame.pkt_dts and AVFrame.time_base to match the original frame time from the source file... but I tried to do so and the video was a complete mess.

So, any ideas on how to address this?