Converting MPEG-2 files

[martyr.kerplunk]

Hi guys.

I got this video from a client with stereo format and he wants me to change the audio to 5.1 surround channel. He gave me MPEG type video format and 6 channel, as usual.

So, to put the surround audio back together, I use FCP X. But since FCP X can't read mpg type file, I have to convert the original video first using Compressor (as usual). Normally I use [Apple ProRes 422 HQ, audio passthrough] to do the job, then combine it back using FCP X.

The thing is, this time when i convert it using Compressor, there's minor digital glitch throughout the whole video. When I play the original video using VLC Player, all seems fine.



Is there any type of good converter for mpg type file?(preferrably free since I'm just a beginner and don't have much money)
Or perhaps different ways to do it?

Here's the info for my video:



note: I've already tried Handbrake (somehow the video/audio suddenly out of sync, maybe drop frames IDK), All-In-One Video Converter (it changes the fps), and of course Compressor.

[hech54]

My favorite tool for swapping audio is AviDemux. You can check and adjust the sync and output both audio and video without re-encoding. I have never worked with 5.1 though.....I have no use for it. It should be the same though.
COPY
COPY
MPEG-PS
should be the output setting you are looking for once you exchange the audio.

[Cornucopia]

You made our and your life more difficult by not giving us the audio properties on that screencap.

Back Up.
Don't use a screen cap.
Use a detailed/advanced mode text readout from MediaInfo, and then either copy & paste the text, or do a text mode export and copy & paste the text from the text file. Or even upload the text file.

But you must also understand a few things:
1. You cannot just turn a 2ch/stereo audio file into a true 5.1/surround audio file. You might be able to get 5.1 channels out of it, but they won't be mixed right. This is important!
2. To do this right, you need a 5.1 (aka 6) channel source file (or 6 separate single channel files, or 3 appropriate stereo pair files...).
3. To continue to do this right, you should NOT be using FCPX for this. AFA Mac apps, I would only recommend (in decreasing order) ProTools, Logic, Audition. IOW, a DAW. In a pinch, you could try older FCP, Premiere Pro, or AVID MC, but I couldn't guarantee they would do the mixdown correctly.
4. While FCPX can do surround sound, there are a number of gotchas, and you will likely have to reconfigure your project setting more than once, and then fudge with the track assignments & surround panners to get things even close, and (depending upon your system) you may or may not be able to export LPCM6ch or AC-3surround (sometimes one, sometimes the other). Again, IMO this is best left to an audio-centric app.
5. If you intend to go ahead with FCPX doing this, AND you have valid 6ch sources but they're muxed into an MPG file, use ffmpeg and/or its mac GUI app: iFFmpeg. Then just demux to raw streams before importing into FCPX.
6. If your distribution-ready video is the MPEG, but its audio is 2 ch. and you have 6ch source files and want to match the 6ch to the 2ch+vid, then convert the MPG also to ProRes (in iFFmpeg) or similar, temporarily. Load everything (ProRes vid+2ch aud+6ch aud) into the NLE, match the cuts, and then export ONLY the 6ch audio (to LPCM). Then use iFFmpeg or Compressor to convert to AC3 if necessary, and use iFFmpeg to mux the originally demuxed MPG video with the 6ch audio.
7. Notice: you shouldn't be affecting/adjusting the video portion AT ALL. So just re-use it (the original) when bringing back in the surround audio. Otherwise, you lose quality.

Scott

[martyr.kerplunk]

My favorite tool for swapping audio is AviDemux. You can check and adjust the sync and output both audio and video without re-encoding. I have never worked with 5.1 though.....I have no use for it. It should be the same though.
COPY
COPY
MPEG-PS
should be the output setting you are looking for once you exchange the audio.

Thanks Hech, wil try it later.

[martyr.kerplunk]

You made our and your life more difficult by not giving us the audio properties on that screencap.

Back Up.
Don't use a screen cap.
Use a detailed/advanced mode text readout from MediaInfo, and then either copy & paste the text, or do a text mode export and copy & paste the text from the text file. Or even upload the text file.

But you must also understand a few things:
1. You cannot just turn a 2ch/stereo audio file into a true 5.1/surround audio file. You might be able to get 5.1 channels out of it, but they won't be mixed right. This is important!
2. To do this right, you need a 5.1 (aka 6) channel source file (or 6 separate single channel files, or 3 appropriate stereo pair files...).
3. To continue to do this right, you should NOT be using FCPX for this. AFA Mac apps, I would only recommend (in decreasing order) ProTools, Logic, Audition. IOW, a DAW. In a pinch, you could try older FCP, Premiere Pro, or AVID MC, but I couldn't guarantee they would do the mixdown correctly.
4. While FCPX can do surround sound, there are a number of gotchas, and you will likely have to reconfigure your project setting more than once, and then fudge with the track assignments & surround panners to get things even close, and (depending upon your system) you may or may not be able to export LPCM6ch or AC-3surround (sometimes one, sometimes the other). Again, IMO this is best left to an audio-centric app.
5. If you intend to go ahead with FCPX doing this, AND you have valid 6ch sources but they're muxed into an MPG file, use ffmpeg and/or its mac GUI app: iFFmpeg. Then just demux to raw streams before importing into FCPX.
6. If your distribution-ready video is the MPEG, but its audio is 2 ch. and you have 6ch source files and want to match the 6ch to the 2ch+vid, then convert the MPG also to ProRes (in iFFmpeg) or similar, temporarily. Load everything (ProRes vid+2ch aud+6ch aud) into the NLE, match the cuts, and then export ONLY the 6ch audio (to LPCM). Then use iFFmpeg or Compressor to convert to AC3 if necessary, and use iFFmpeg to mux the originally demuxed MPG video with the 6ch audio.
7. Notice: you shouldn't be affecting/adjusting the video portion AT ALL. So just re-use it (the original) when bringing back in the surround audio. Otherwise, you lose quality.

Scott

Hi Scott, sorry for my bad explanation. M
My client gave me 2 folder - an mpeg-2 file with stereo audio in a folder, and 6 separate audio channel (L, R, C, LFe, Ls, Rs) in the other folder.


I never quite sure how to use ffmpeg. Been looking at 'how to use ffmpeg' and few guides since last week, but I'm still not quite sure how to use it correctly

Matt

[pandy]

Hi Scott, sorry for my bad explanation. M
My client gave me 2 folder - an mpeg-2 file with stereo audio in a folder, and 6 separate audio channel (L, R, C, LFe, Ls, Rs) in the other folder.


I never quite sure how to use ffmpeg. Been looking at 'how to use ffmpeg' and few guides since last week, but I'm still not quite sure how to use it correctly

Matt

Give a chance to https://trac.ffmpeg.org/wiki/AudioChannelManipulation .

I would do first - turn 6 audio streams to multichannel file,
second (optional and can be accommodated in first step) turn multichannel to some consumer accepted audio (for example AC3 aka Dolby Digital)
third mux additional multichannel track to already existing mpeg-2 stream (can be done trough ffmpeg or for example tsmuxer or any convenient to you tool)

[martyr.kerplunk]

*Updated:

I manage to turn the 6 audio stream to 1 (5.1) streams suing ffmpeg. I tried to replace the audio from the original file with this one using this command

ffmpeg -i Video_Stereo.mpg -i 5_1_audio.wav \
-c:v copy -c:a aac -strict experimental \
-map 0:v:0 -map 1:a:0 Video_5_1.mpg

Somehow, the output has no readable audio. Since I've been working on this work for quite some time now, I don't really want to waste any minute anymore.

So I just mux those files together using TSmuxer. And, of course, the video is in ts container. But, hey, all in all it works out. No glitch video with 5.1 output.

Maybe it's just a little thing (finding the right guides to install the ffmpeg, using it and so on), but at least a progress for me.

Thanks Pandy for the advice. Cheers