how to add ac3 to mkv

[adaz]

Hey guys.

I recently downloaded something with dual audio. The 2nd audio language is in a seperate ac3 file. I want to merge it with the mkv, or replace it with the other language. I need to do this because i will then convert mkv to mp4 using gotsent.

Please let me know how I can do so.

thanks

[Baldrick]

Use mkvmerge that is included in mkvtoolnix.

[adaz]

thanks

[PuzZLeR]

Just be careful to adjust your video to the correct framerate (FPS) in Format specific options otherwise it will be out of sync with your audio.

I'm assuming since you're in Canada as I am you have may have an NTSC video stream which is usually 29.97fps. The default in MKVmerge is 25fps.

[Xavier]

I have a follow up to these, as I am doing the same now. I can't add any audio with mkvmerge. What MIME type should I choose? I have tried with different MIME types for AC3, got frustrated and tried MP3, but I couldn't do that either. I don't get any errors, but the audio track isn't available in the muxed mkv

Also, is it possible to change the speed of an ac3 without encoding it? I want to keep 5.1 ac3, but change it from 25 fps to 23,97, I have a PAL audio track I want to add to an NTSC source. The video source ain't available in PAL and the audio language ain't available in NTSC ;]

As an alternative that might be better, how/what program should I use to change a 23,7 FPS x264 video to 25 fps without losing image quality?

[ckamc]

I would recommend keeping the frame rate the exact same the whole way.

I tried to mess with one of my 23.976 and go flat 24 and my mp4 didnt like it.

[Xavier]

I would recommend keeping the frame rate the exact same the whole way.

I tried to mess with one of my 23.976 and go flat 24 and my mp4 didnt like it.

It pretty much says itself that a PAL audio from a 25 fps movie don't fit a NTSC video with 23,7 fps... I need to convert one of them...

And more importantly, I can't even merge audio with MKVmerge :S Which MIME type do I use for AC3 and what MIME type do I use for MP3? I can't get it to work.

[Midzuki]

There's something wrong with your MKVmerge and/or with the settings
of your OS. MKVmerge should pay attention to FourCC codes, not to
MIME-types. Hopefully other members will help you more than I.

[Xavier]

It might be just me being stupid and not something wrong

To be sure this is what I have done.

First I start MKVmerge GUI and in "Input" I add the original mkv. I remove the unwated subtitles and an extra audio track I don't want. After that I go to Attachments and add the ac3 track. Is this correct? If I just try to mux it without selecting a MIME type I get the error "No MIME type has been selected for the attachment ***.mka". I also tried renaming it to ac3 and encoding it to mp3, same thing then.

[Midzuki]

First I start MKVmerge GUI and in "Input" I add the original mkv. I remove the unwated subtitles and an extra audio track I don't want. After that I go to Attachments and add the ac3 track. Is this correct?

No. You should be back to the button "add" on the tab "Input".

[ckamc]

I would go and extract the video in my opinion with mkv extract, then you will have the raw video and ignore the other audio track... so your end result will ONLY be the two things you want.....

the video and the audio you wanted.

also, if in the save as section it says .mks make sure to manually change the s to a v

[Xavier]

First I start MKVmerge GUI and in "Input" I add the original mkv. I remove the unwated subtitles and an extra audio track I don't want. After that I go to Attachments and add the ac3 track. Is this correct?

No. You should be back to the button "add" on the tab "Input".

Thanks