Sync audio and video of different DVDs

[Knocks]

I have two rips of the same movie published on DVD in different countries. One has a superior picture, so I would like to add a foreign language track from the other DVD to the one with better video.

The problem is that the English DVD is 34 seconds longer than the foreign one. It doesn't have any extra scenes. It's just longer. If you play both videos side-by-side, they slowly get out of sync. They are both PAL 25.0000 FPS, so it baffles me how this happened. I tried extracting the timecodes from the shorter video, importing it in the longer video along with the audio, and remuxing, and that did not work (I got a 3-hour movie instead of a 90-minute one and it didn't play correctly).

What's the best way to add the shorter audio track (and subtitles) to the longer video? I would prefer to avoid re-encoding the movie and keep it in the original MPEG-2 stream in a MKV container.

[jagabo]

If it's really as you say: stretch the audio in an editor like Audacity (free). Mux the new audio with the video.

[Knocks]

I read something about making the video play faster without reencoding instead of slowing the audio down, which loses quality and reportedly causes distortion. Is that an option?

[video.baba]

Do both movies/videos start the same? The same frames at the beginning? Same movie logos titles etc... ?

Maybe forget about the subtitle track for now, you can come back to that later.

I think the first thing I'd do is extract both audio tracks and compare the length. Use an audio editor and stretch the shorter audio to the same length as the longer. Add the new audio to the movie, give it a try. It seems a little 'hackish' but it's certainly worth a try in the first instance.

[Knocks]

Audacity crashes when importing this AC3 file. I have tried both the portable and the installable version So I'm kind of stuck.

[video.baba]

How did you extract the AC3 from the movie?

[Knocks]

Rip the DVD with MakeMKV, then extract the audio track with gMKVExtractGUI.

[manono]

Convert that AC3 audio to WAV audio and then open it in Audacity. It still won't work, though.

It doesn't have any extra scenes. It's just longer.

You know that makes no sense at all, don't you? Is the framecount identical between the two versions? No.

I read something about making the video play faster without reencoding instead of slowing the audio down, which loses quality and reportedly causes distortion. Is that an option?

No, not for DVD it's not an option.

[Knocks]

You know that makes no sense at all, don't you? Is the framecount identical between the two versions? No.

I described it exactly as it is. You press play on both files and everything is the same, but one of the videos slowly starts falling behind, and by the end of the movie it's 34 seconds behind.

I read something about making the video play faster without reencoding instead of slowing the audio down, which loses quality and reportedly causes distortion. Is that an option?

No, not for DVD it's not an option.

According to the MKVtoolnix documentation, you should avoid stretching audio and "shrink" video instead by telling the player to play it faster. How can I stretch or shrink an audio track?

[video.baba]

Any chance you could post a Mediainfo dump (text mode) of both ripped files?

[jagabo]

Audacity crashes when importing this AC3 file. I have tried both the portable and the installable version So I'm kind of stuck.

Have you installed the ffmpeg plugin for Audacity. With that installed Audacity can import audio from almost any A/V file (no need to demux first). For example, you can just drag/drop an MKV file onto Audacity.

https://manual.audacityteam.org/man/faq_installation_and_plug_ins.html#ffdown

[Knocks]

Have you installed the ffmpeg plugin for Audacity. With that installed Audacity can import audio from almost any A/V file (no need to demux first).

It crashes with the MKV too

Any chance you could post a Mediainfo dump (text mode) of both ripped files?

Sure.

The longer video:

Format                         : Matroska
Format version                 : Version 4 / Version 2
File size                      : 4.55 GiB
Duration                       : 1 h 32 min
Overall bit rate mode          : Variable
Overall bit rate               : 7 059 kb/s
Encoded date                   : UTC 2019-07-31 21:22:40
Writing application            : mkvmerge v33.1.0 ('Primrose') 64-bit
Writing library                : libebml v1.3.7 + libmatroska v1.5.0

Video
ID                             : 1
Format                         : MPEG Video
Format version                 : Version 2
Format profile                 : Main@Main
Format settings                : CustomMatrix
Format settings, BVOP          : No
Format settings, Matrix        : Custom
Format settings, picture struc : Frame
Codec ID                       : V_MPEG2
Codec ID/Info                  : MPEG 1 or 2 Video
Duration                       : 1 h 32 min
Bit rate mode                  : Variable
Bit rate                       : 7 057 kb/s
Maximum bit rate               : 9 800 kb/s
Width                          : 720 pixels
Height                         : 576 pixels
Display aspect ratio           : 16:9
Frame rate mode                : Variable
Frame rate                     : 25.000 FPS
Standard                       : PAL
Color space                    : YUV
Chroma subsampling             : 4:2:0
Bit depth                      : 8 bits
Scan type                      : Interlaced
Scan order                     : Top Field First
Compression mode               : Lossy
Bits/(Pixel*Frame)             : 0.681
Time code of first frame       : 00:00:00:00
Time code source               : Group of pictures header
Stream size                    : 4.55 GiB (100%)
Default                        : Yes
Forced                         : Yes

The shorter video

Format                         : Matroska
Format version                 : Version 2
File size                      : 4.14 GiB
Duration                       : 1 h 31 min
Overall bit rate mode          : Variable
Overall bit rate               : 6 466 kb/s
Encoded date                   : UTC 2019-08-06 22:38:55
Writing application            : MakeMKV v1.14.4 win(x64-release)
Writing library                : libmakemkv v1.14.4 (1.3.5/1.4.7) win(x64-release)

Video
ID                             : 1
ID in the original source medi : 224 (0xE0)
Format                         : MPEG Video
Format version                 : Version 2
Format profile                 : Main@Main
Format settings                : CustomMatrix / BVOP
Format settings, BVOP          : Yes
Format settings, Matrix        : Custom
Format settings, picture struc : Frame
Codec ID                       : V_MPEG2
Codec ID/Info                  : MPEG 1 or 2 Video
Duration                       : 1 h 31 min
Bit rate mode                  : Variable
Bit rate                       : 5 553 kb/s
Maximum bit rate               : 8 000 kb/s
Width                          : 720 pixels
Height                         : 576 pixels
Display aspect ratio           : 4:3
Frame rate mode                : Constant
Frame rate                     : 25.000 FPS
Standard                       : PAL
Color space                    : YUV
Chroma subsampling             : 4:2:0
Bit depth                      : 8 bits
Scan type                      : Interlaced
Scan order                     : Top Field First
Compression mode               : Lossy
Bits/(Pixel*Frame)             : 0.536
Time code of first frame       : 00:59:59:00
Time code source               : Group of pictures header
Stream size                    : 3.56 GiB (86%)
Default                        : No
Forced                         : No
Original source medium         : DVD-Video

Audio #1
ID                             : 2
ID in the original source medi : 189 (0xBD)128 (0x80)
Format                         : AC-3
Format/Info                    : Audio Coding 3
Codec ID                       : A_AC3
Duration                       : 1 h 31 min
Bit rate                       : 448 kb/s
Channel(s)                     : 6 channels
Sampling rate                  : 48.0 kHz
Frame rate                     : 31.250 FPS (1536 SPF)
Compression mode               : Lossy
Stream size                    : 293 MiB (7%)
Title                          : Surround 5.1
Default                        : Yes
Forced                         : No
Original source medium         : DVD-Video

Audio #2
ID                             : 3
ID in the original source medi : 189 (0xBD)129 (0x81)
Format                         : AC-3
Format/Info                    : Audio Coding 3
Format settings, Endianness    : Big
Codec ID                       : A_AC3
Duration                       : 1 h 31 min
Bit rate mode                  : Constant
Bit rate                       : 224 kb/s
Channel(s)                     : 2 channels
Channel positions              : Front: L R
Sampling rate                  : 48.0 kHz
Frame rate                     : 31.250 FPS (1536 SPF)
Bit depth                      : 16 bits
Compression mode               : Lossy
Stream size                    : 147 MiB (3%)
Title                          : Stereo
Service kind                   : Complete Main
Default                        : No
Forced                         : No
Original source medium         : DVD-Video

Audio #3
ID                             : 4
ID in the original source medi : 189 (0xBD)130 (0x82)
Format                         : AC-3
Format/Info                    : Audio Coding 3
Codec ID                       : A_AC3
Duration                       : 1 h 31 min
Bit rate                       : 224 kb/s
Channel(s)                     : 2 channels
Sampling rate                  : 48.0 kHz
Frame rate                     : 31.250 FPS (1536 SPF)
Compression mode               : Lossy
Stream size                    : 147 MiB (3%)
Title                          : Stereo
Default                        : No
Forced                         : No
Original source medium         : DVD-Video

Text #1
ID                             : 5
ID in the original source medi : 189 (0xBD)32 (0x20)
Format                         : VobSub
Codec ID                       : S_VOBSUB
Codec ID/Info                  : Picture based subtitle format used on DVDs
Duration                       : 1 h 30 min
Bit rate                       : 4 231 b/s
Count of elements              : 832
Stream size                    : 2.74 MiB (0%)
Default                        : Yes
Forced                         : No
Original source medium         : DVD-Video

Text #2
ID                             : 6
ID in the original source medi : 189 (0xBD)33 (0x21)
Format                         : VobSub
Codec ID                       : S_VOBSUB
Codec ID/Info                  : Picture based subtitle format used on DVDs
Duration                       : 1 h 31 min
Bit rate                       : 6 875 b/s
Count of elements              : 1397
Stream size                    : 4.49 MiB (0%)
Default                        : No
Forced                         : No
Original source medium         : DVD-Video