How to put audio from one video to another

[amxcs]

What is the easiest way to put the sound from the video with a lower resolution to the other with a higher one?
Need to convert framerate? Which is the correct way - on the video or on the sound? And how?

General
Unique ID                      : 331632889004050566256917554047996010971 (0xF97E2BD0552CC88C632C59E280C621DB)
Complete name                  : D:\ALF.01x01.720p.DVDRemux.MPEG2.AC3-STM.mkv
Format                         : Matroska
Format version                 : Version 4
File size                      : 980 MiB
Duration                       : 24 min 13 s
Overall bit rate mode          : Variable
Overall bit rate               : 5 655 kb/s
Frame rate                     : 25.000 FPS
Movie name                     : ALF.S01E01-STM
Encoded date                   : 2020-04-18 12:21:22 UTC
Writing application            : mkvmerge v45.0.0 ('Heaven in Pennies') 64-bit
Writing library                : libebml v1.3.10 + libmatroska v1.5.2
Cover                          : Yes
Attachments                    : cover.jpg

Video
ID                             : 1
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, GOP           : M=3, N=15
Format settings, picture struc : Frame
Codec ID                       : V_MPEG2
Codec ID/Info                  : MPEG 1 or 2 Video
Duration                       : 24 min 13 s
Bit rate mode                  : Variable
Bit rate                       : 4 691 kb/s
Maximum bit rate               : 7 500 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)             : 0.452
Time code of first frame       : 00:00:00:00
Time code source               : Group of pictures header
GOP, Open/Closed               : Open
GOP, Open/Closed of first fram : Closed
Stream size                    : 813 MiB (83%)
Title                          : MPEG2, 576i50, 25.000 fps
Default                        : No
Forced                         : No

Audio #1
ID                             : 2
Format                         : AC-3
Format/Info                    : Audio Coding 3
Commercial name                : Dolby Digital
Codec ID                       : A_AC3
Duration                       : 24 min 13 s
Bit rate mode                  : Constant
Bit rate                       : 192 kb/s
Channel(s)                     : 2 channels
Channel layout                 : L R
Sampling rate                  : 48.0 kHz
Frame rate                     : 31.250 FPS (1536 SPF)
Compression mode               : Lossy
Stream size                    : 33.3 MiB (3%)
Title                          : Bulgarian, AC3, 2.0, 192 kbps
Language                       : Bulgarian
Service kind                   : Complete Main
Default                        : Yes
Forced                         : No

General
Complete name                  : D:\Alf S01E01 A.L.F..mp4
Format                         : MPEG-4
Format profile                 : Base Media / Version 2
Codec ID                       : mp42 (mp42/iso2/avc1/mp41)
File size                      : 443 MiB
Duration                       : 24 min 11 s
Overall bit rate mode          : Variable
Overall bit rate               : 2 562 kb/s
Frame rate                     : 23.976 FPS
Encoded date                   : 2022-07-17 13:08:13 UTC
Tagged date                    : 2022-07-17 13:08:13 UTC
Writing application            : HandBrake 1.4.0 2021071800

Video
ID                             : 1
Format                         : AVC
Format/Info                    : Advanced Video Codec
Format profile                 : High@L4.1
Format settings                : CABAC / 1 Ref Frames
Format settings, CABAC         : Yes
Format settings, Reference fra : 1 frame
Codec ID                       : avc1
Codec ID/Info                  : Advanced Video Coding
Duration                       : 24 min 11 s
Bit rate                       : 2 397 kb/s
Width                          : 1 432 pixels
Height                         : 1 072 pixels
Display aspect ratio           : 4:3
Frame rate mode                : Variable
Frame rate                     : 23.976 (24000/1001) FPS
Minimum frame rate             : 23.974 FPS
Maximum frame rate             : 23.981 FPS
Color space                    : YUV
Chroma subsampling             : 4:2:0
Bit depth                      : 8 bits
Scan type                      : Progressive
Bits/(Pixel*Frame)             : 0.065
Stream size                    : 415 MiB (94%)
Writing library                : x264 core 163 r3059 b684ebe0
Encoding settings              : cabac=1 / ref=1 / deblock=1:0:0 / analyse=0x3:0 / me=hex / subme=9 / psy=0 / mixed_ref=0 / me_range=16 / chroma_me=0 / trellis=0 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=0 / chroma_qp_offset=0 / threads=24 / lookahead_threads=16 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=0 / weightp=0 / keyint=240 / keyint_min=24 / scenecut=100 / intra_refresh=1 / rc_lookahead=32 / rc=crf / mbtree=0 / crf=24.8 / qcomp=1.00 / qpmin=0 / qpmax=69 / qpstep=2 / vbv_maxrate=62500 / vbv_bufsize=78125 / crf_max=0.0 / nal_hrd=none / filler=0 / ip_ratio=1.00 / aq=3:0.05
Encoded date                   : 2022-07-17 13:08:13 UTC
Tagged date                    : 2022-07-17 13:08:13 UTC
Color range                    : Limited
Color primaries                : BT.709
Transfer characteristics       : BT.709
Matrix coefficients            : BT.709
Codec configuration box        : avcC

Audio
ID                             : 2
Format                         : AAC LC
Format/Info                    : Advanced Audio Codec Low Complexity
Codec ID                       : mp4a-40-2
Duration                       : 24 min 11 s
Source duration                : 24 min 11 s
Bit rate mode                  : Constant
Bit rate                       : 160 kb/s
Channel(s)                     : 2 channels
Channel layout                 : L R
Sampling rate                  : 48.0 kHz
Frame rate                     : 46.875 FPS (1024 SPF)
Compression mode               : Lossy
Stream size                    : 27.7 MiB (6%)
Source stream size             : 27.7 MiB (6%)
Title                          : Stereo / Stereo
Language                       : English
Default                        : Yes
Alternate group                : 1
Encoded date                   : 2022-07-17 13:08:13 UTC
Tagged date                    : 2022-07-17 13:08:13 UTC
mdhd_Duration                  : 1451755

[ProWo]

You can use clever FFmpeg-GUI to change the audio, so the video quality isn't changed.


[Attachment 75936 - Click to enlarge]

[amxcs]

The new duration should be 00:24:11.
The content of both video files is exactly the same. From start to finish 1:1. Only 2 seconds difference.
Why does this happen?

[ProWo]

Because the 23.976 fps video is shorter then the 25 fps video.
The two videos are not the same.

[amxcs]

Yes, by 2 seconds.
And when I convert audio from 25 to 23.967, there is a difference of over 1 minute.

As a test, I tried putting the audio from a 25fps video into the video with 23.976 at the beginning of the video it is fine, but towards the end of the video there is a discrepancy of 1-2 seconds.

[ProWo]

Yes, by 2 seconds.
And when I convert audio from 25 to 23.967, there is a difference of over 1 minute.

As a test, I tried putting the audio from a 25fps video into the video with 23.976 at the beginning of the video it is fine, but towards the end of the video there is a discrepancy of 1-2 seconds.

The second video (at 23.976 fps) is not encoded correctly. If the frames content is exactly the same, this video MUST have a longer duration than the 25 fps video.
The first video displays 25 frames per second, the second 23.976 frames per second, which means that the second video takes longer to display all frames.
The 23.976 fps video was obviously re-encoded from a source with a different fps without adjusting the duration, and frames were lost in the process.
This 23.976 fps video also has a variable frame rate.
Mux this mp4 into an mkv container and see what framerate is displayed in mediainfo.

[amxcs]

I think it's the same?

[ProWo]

No, it's not the same.
Now mux the 25 fps audio to the new mkv video.

[amxcs]

Again 2 sec out of sync towards the end of the video.
I've tried reducing the audio by 2 seconds or increasing the video by 2 seconds then it's synced but I'm not sure that's the right way.

[ProWo]

Then try this:
The exact duration in seconds of the audio stream of the 25 fps video is already specified in the upper field (24:13.920 is equal to 1453.920 seconds).

Determine the exact duration of the 23.976 video (load the video in clever-FFmpeg-GUI and the exact duration will be displayed in the top right corner), convert to seconds and milliseconds (as above) and then enter this value in the second field.


[Attachment 76020 - Click to enlarge]

Then encode the 25 fps audio stream and mux it with the 23.976 video.
The 2 second difference is now gone.

This operation (see picture above) must clearly be carried out with the 25 fps video audio stream.


If the audio is still not synchronized, you will have to adjust it manually.
As I said, the two videos are not identical.

[amxcs]

Thanks! This is exactly what I needed!

[ProWo]

You are right, the two values must be swapped.
I'm glad it worked.
Leave a positive review.

[amxcs]

Leave a positive review.

Of course, but I don't know how?

[ProWo]

Leave a positive review.

Of course, but I don't know how?

see here


[Attachment 76031 - Click to enlarge]

[amxcs]

Done.

The problem is that the next episode is 4 seconds longer.
When I compared it, it turned out that there is 1.5 seconds more at the beginning and 1-2 seconds at the end.
I tried converting the audio by a factor of 1.001491 and moving it by 1.5s, at the beginning it's fine, but at the end the video is out of sync again.
I'm getting tired already, I've done it with another series and it was very quick and easy. But I had no problems with the frames there.

[johns0]

Most likely there will be different scene changes which can be longer or shorter compared to the other video,you will need to check at the first scene change how long it goes and edit the audio,this will need to be done for all the scene changes if that's the issue.