FLV to MP4 No Quality Loss - Dont work :(

[CrystalMethod]

Hi all. I am newbie at this and just few days ago find out that is no quality loss convert even possible. I have flv file and try to convert to mp4 (with no quality loss) with ffmpeg, avidemux, yamb and flv extract with no luck. I get this errors :

in ffmpeg: Could not find tag for codec vp6f in stream #0, codec n
ot currently supported in container

in avidemux: Unsupported : Only MP4Video & H264 supported for video

I realize that mine flv has :

Stream #0:0: Video: vp6f, yuv420p, 512x384, 491 kb/s, 29.97 tbr, 1k tbn, 1k tbc
Stream #0:1: Audio: mp3, 44100 Hz, stereo, s16p, 130 kb/s

So i ask you experts is it even possible to convert this flv to mp4 with no quality loss.... if NOT can you tell me best settings in ffmpeg to convert to mp4 and be high quality. Thanks

[hech54]

If you are converting....there will be quality loss.

[yoda313]

Have you tried winff? Search the forum for the pass thru presets that forum member bat999 shared. It will remux the video from one container to another without converting.

However your device has to be able to recognize the video that's in the container. Just because you have a mp4 file doesn't mean every unit will play it.

For that you will have to convert it to that devices specifications which will introduce some quality loss as hech54 mentioned.

Though if its for an android or ios device you should search for a flv app to play the video natively without converting.

Good luck.

[jagabo]

I don't think vp6f is allowed in MP4.

[CrystalMethod]

I don't think vp6f is allowed in MP4.

ok as i said if its not possible to get same quality can somebody tell me good settings in ffmpeg to make mp4 with high quality closest to original one or can i convert flv to other format (with no quality loss) but that is friendly to sony vegas ?

[smrpix]

If you need to bring the file into Vegas you can convert it into something lossless like lagarith or huffyuv. The files will be huge but they are temporary. After editing you can export from Vegas to whatever kind of mp4 you need with minimal loss.

It helps to know your end goal to suggest workflows.

[bat999]

... settings in ffmpeg to make mp4...

Try this for your first attempt:-

ffmpeg -i input.flv -c:v libx264 -crf 23 -preset medium -c:a aac -strict -2 -b:a 128k -ar 44100 -ac 2 output.mp4

[hello_hello]

I don't think vp6f is allowed in MP4.

ok as i said if its not possible to get same quality can somebody tell me good settings in ffmpeg to make mp4 with high quality closest to original one or can i convert flv to other format (with no quality loss) but that is friendly to sony vegas ?

I wouldn't have a clue what Sony Vegas will work with, but MKVMergeGUI can open flv files and save the output as MKV. You can probably go from flv to MKV that way without converting anything.
Alternatively, convert the flv to a lossless AVI/MKV/MP4 and use it for editing/converting with Sony Vegas. Video to Video converter will do it. Choose an output preset after opening the flv file, change the output codec to ffv1 (lossless) and the audio to either "copy" or "pcm".

When you open an flv with Video To Video Converter you can also choose Direct Stream Copy from the list of conversion presets. Change the output container to something else (avi or mp4 etc) and Video To Video converter will remux the audio/video for you. As not all video/audio types can be used with every container, trying to copy them to a different container may result in an error, an unusable file, or something which works perfectly.

[CrystalMethod]

... settings in ffmpeg to make mp4...

Try this for your first attempt:-

ffmpeg -i input.flv -c:v libx264 -crf 23 -preset medium -c:a aac -strict -2 -b:a 128k -ar 44100 -ac 2 output.mp4

thanks man video looks flawless