How to join four .flv files in to one .flv file using ffmpeg?

[spiderMan007]

Hi all can any one show me how i can combine 4 different .flv files(each different size produced by rtmpdump) in two one big .flv file using ffmpeg so the original quality is preserved ?should i use rtmpdump or ffmpeg for this purpose and how ?

[Baldrick]

andys flv joiner.

But do they have different video frame sizes?

[spiderMan007]

andys flv joiner.

But do they have different video frame sizes?

thanks for your reply. The flv files are from the same stream so i assume that they have same frame sizes ! is there a way to check that? My goal is to eventually convert the merged .flv file to mp3 while preserving the quality of the video. Can ffmpeg do that ? if yes how ?

[Baldrick]

I use Freemake, just add the vids, click the join button at the top right and convert to whatever other format you like

It will be reconverted.

No, I have never done any joining with ffmpeg.