Audio out of sync when converted to h.264

[cisasteelersfan]

I have tried HDTV2MPEG2 and iFrame. They cut the commercials fine (no audio sync issues), but when I convert that file to h.264 (for my iPod) the audio ends up out of sync. This happens every single time I try to convert, doesn't matter what converter I use. Is this the fault of HDTV2MPEG2? Or is it the fault of the video converters?

Any ideas are appreciated.

[cisasteelersfan]

I've done some digging around in other forums and it sounds like I have an audio drift. Does anyone know how to correct this? Should I use a different setting when recording in GBPVR?

[sub]

Does anyone know how to correct this? Should I use a different setting when recording in GBPVR?

There is unlikely to be any setting in GB-PVR that would make any difference to this. Digital recordings are just an exact copy of what your broadcaster transmitted. Any fix would more likely be in HDTV2MPEG2 or iFrame, or through switching to some alternate software for this same job.

[raceviper13]

I know exactly what you're running into. It's at the breaks that HDTV2MPEG2 breaks the audio sync. Mencoder is the only program that can take an edited HDTV2MPEG2 stream and keep the synchronization throughout the conversion process, but it's h264 creation leaves a lot to be desired compared to x264. If you want, apparently VideoReDo keeps sync after cutting commercials, but it's not free. Here is my solution (free):
1. cut commercials using HDTV2MPEG2.
2. demux audio from video using ProjectX (get the latest build at http://oozoon.de/main_en.html) ProjectX is the magic here. It will demux the audio and video into two separate files that can be processed independently. The cool part is that it keeps the sync between both files.
3. use DGMPGDec to create valid d2v file from demuxed video file to input into Avisynth. (get it at http://neuron2.net/dgmpgdec/dgmpgdec.html).
4. create avisynth file and load into x264 (output to mkv or else you may encounter problems).
5. convert AC3 (if desired) into AAC using BeSweet.
6. mux audio and video into mkv using mkvtoolnix (mkvmerge).

I have a smart batch file I use to automatically crop the video and it has options for scaling and ivtc conversion to film and PAL.

If you have any questions, please let me know.

[cisasteelersfan]

Sweet Raceviper! Thanks so much for the reply. I'll try the instructions and get back to you.

[cisasteelersfan]

Sorry I'm such a noob. I demuxed the audio alright with Project X. I used DGMPGDec and got a d2v file. How do I import it to avisynth? How do I load into x264? Detailed, step-by-step instructions are best. Sorry I'm a n00b

[pBS]

that's a sign of a bad cutter, it's not redoing the timeline where it cuts...
and mencoder can actually use the x264 codec if you set it up..
but really it's about the cuts, they must be done right or you have to go thru all this..
videoredo can cut them correctly, as well as a couple others..
progs that cut on i-frames will produce perfect cuts everytime...otherwise need complete re-encode..
i believe mpgtx cuts on gop so would produce good cuts on mpeg2..

or you can cut it like you wish and just remux it after to fix the timeline...retime does this well, or i believe ffmpeg actually can, or any demux/mux combo..

[raceviper13]

for avisynth, here is a representative script (Thomas & Friends - Determination.avs) for a file of mine that is transcoding right now:

----------------
LoadPlugin("C:\Program Files (x86)\DGMPGDecode\DGDecode.dll")
LoadPlugin("C:\Program Files (x86)\AviSynth 2.5\plugins\TIVTC.dll")
MPEG2Source("C:\TEMP\Thomas & Friends - Determination.d2v")
TFM(d2v="C:\TEMP\Thomas & Friends - Determination.d2v")
BilinearResize(960, 720, 256, 8, -259, -13)
----------------

FYI, TIVTC will deinterlace for you (or film conversion if needed)

Then you load the script right into x264:

START "x264" /B /LOW /WAIT "C:\Program Files (x86)\x264\x264.exe" --tune ssim --partitions p8x8,b8x8,i8x8,i4x4 --bframes 2 --ref 4 --me hex --subme 4 --mixed-refs --crf 23 --nr 0 --threads 0 --thread-input --output "D:\Converted\Thomas & Friends - Determination.mkv" "C:\TEMP\Thomas & Friends - Determination.avs"

you would replace "Thomas & Friends - Determination" with whatever you want.

as for making an iPod video, I don't know the specific settings in x264 for that.

as for pBS, yes you are correct, HDTV2MPEG2 is a bad cutter, but is free and I've figured out how to get around the problems. Mencoder and ffmpeg have given me fits so much I had to abandon them completely.