How to stop Avidemux from removing soft-coded subtitles.

Started by Matthew R, November 03, 2020, 02:01:57 PM

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Matthew R

I am a very novice user, so my knowledge of video editing is basic, at best. That said, I use Avidemux to convert video files with 6 channel audio to stereo audio. The problem I'm having is that Avidemux always removes soft-coded subtitles when I do it and I would like to keep the subs.

Is there any way to convert a video file from 6 channel audio to stereo audio without losing the subtitles?

Thank you in advance for any help.

eumagga0x2a

Quote from: Matthew R on November 03, 2020, 02:01:57 PMIs there any way to convert a video file from 6 channel audio to stereo audio without losing the subtitles?

There is no support for subtitle tracks in Avidemux, so unless you are able to contribute code which would implementing this support in core libraries, in demuxers (MpegTS, Mp4 and Matroska), in editor and in muxers (MP4, MKV and MPEG-TS), you need to use a different tool. If no editing apart from starting output at an offset is necessary, the command-line ffmpeg would be the most obvious solution.

Ronstang

#2
What kind of video file are you working with?  There are plenty of tools to do what you want.  Personally I only use Avidemux as an editor and then use MCEBuddy, Xmedia Recode, or FFmpeg Batch AV Converter to do any other operations. If all you are doing is changing the audio track then Xmedia Recode is probably your best bet.  I use MCEBuddy to encode recorded TV and ripped discs into mp4 in an MKV container....and extract the subs, convert them to SRT and put them back into the video container for ease of use.  There are many options here you just have to do a little research.

Personally, I use Emby to organize my video content and play it back on my TV through my Firestick 4K which supports 5.1 channel audio and many video codecs so for me there is no need to waste time making a stereo track.  This way in the den I can use surround and in the bedrooms it automatically plays as stereo.  If you have devices that won't play 5.1 and don't want or need to encode the video then I suggest you look at Xmedia Recode.

eumagga0x2a

Quote from: Ronstang on November 06, 2020, 01:39:52 PMPersonally I only use Avidemux as an editor and then use MCEBuddy, Xmedia Recode, or FFmpeg Batch AV Converter to do any other operations.

Why? When doing so, you are restricted to keyframes as cut points while still losing subtitle tracks.

Quote from: Ronstang on November 06, 2020, 01:39:52 PMI use MCEBuddy to encode recorded TV and ripped discs into mp4 in an MKV container.

Strictly speaking, mp4 is not a codec but a container like MKV.

Ronstang

Quote from: eumagga0x2a on November 06, 2020, 10:05:26 PMWhy? When doing so, you are restricted to keyframes as cut points while still losing subtitle tracks

I still have subtitles in all my files I process through Avidemux.  And if you can tell me how I can edit TS files without being restricted to keyframes I would love to learn.  And yes, I misspoke abut mp4.....I mean't H.264 and now I use H.265 since I got a new video card.

I use other tools to encode because like earlier today I queued 144 files into MCEBuddy before I left and just came home to them almost being finished and I have my subtitles already added back into the container.

eumagga0x2a

#5
Quote from: Ronstang on November 06, 2020, 10:20:42 PMI still have subtitles in all my files I process through Avidemux.

Unless subtitles are hardcoded (i.e. a part of the picture), they are lost when processed by Avidemux, there is no code to handle soft subtitles. Exporting them using a different tool and re-importing after performing cuts with Avidemux means they lose sync with the video (except for videos which are merely truncated).

Quote from: Ronstang on November 06, 2020, 10:20:42 PMAnd if you can tell me how I can edit TS files without being restricted to keyframes I would love to learn.

Copy mode = each segment must start at a keyframe. This limitation doesn't exist when re-encoding (i.e. choose an encoder in Avidemux instead of "Copy", then edit the video).

Quote from: Ronstang on November 06, 2020, 10:20:42 PMI use other tools to encode because like earlier today I queued 144 files into MCEBuddy before I left and just came home to them almost being finished and I have my subtitles already added back into the container.

If some or even the majority of these files were not edited with Avidemux, then sure, batch processing with other tools makes perfectly sense. Else you might want to look into the "File" --> "Add to queue" option in Avidemux and let Avidemux Jobs GUI process the queue.

Ronstang

I'm not sure how I can edit a file without saving by copying or encoding it so it can be queued in Avidemux. And I guess my subs are hardcoded and they are pulled out by MCEBuddy.  Also, I keep all audio tracks, can Avidemux encode and do that?  Can it process four simultaneous encoding sessions like the other programs I use?

eumagga0x2a

Quote from: Ronstang on November 06, 2020, 10:47:54 PMI'm not sure how I can edit a file without saving by copying or encoding it so it can be qu

Instead of saving a file, you add it to the queue after having performed all cuts and configured a filter chain and an encoder. All queued jobs are executed using the Jobs GUI.

Quote from: Ronstang on November 06, 2020, 10:47:54 PMAnd I guess my subs are hardcoded and they are pulled out by MCEBuddy.

If they are hardcoded, they cannot be removed or disabled. Soft subtitles can be generated from hardcoded ones by means of OCR.

Quote from: Ronstang on November 06, 2020, 10:47:54 PMAlso, I keep all audio tracks, can Avidemux encode and do that?

Up to 4 audio tracks are supported for output.

Quote from: Ronstang on November 06, 2020, 10:47:54 PMCan it process four simultaneous encoding sessions like the other programs I use?

No, this is not possible.

Ronstang

Multi-processing is a must for me now, because of my new video card I can process four movies or shows in a little longer than it takes to do one....which makes a huge difference in time, plus I get all my subs done for me automatically too.

Ronstang

I really love Avidemux just the way I use it. it is a lifesaver.  My HTPC runs 24/7 and it is almost always open and I use it almost every day.  The fact that I have to cut on keyframes really isn't an issue because I mostly record commercial free unedited movies and I am only trimming the lead in and out extra stuff as I just want the movie and sometimes the credits and keyframes don't cause a problem here.    Even editing out commercials on TV movies and shows isn't really an issue either since there is usually ample fade to hit on an good break, even when not it really isn't noticeable during playback.  I have watched a a lot of movies off the MGM channel after editing out their commercial breaks and I have yet to notice where that break was before I removed it.

Gew

Pullin' a bit of thread necromancy here.

Is there ANY chance of future implementation of subtitle handling, the way this thread starter suggests?

I have some .MKV files with AVC/AAC for video/audio and embedded .SRT (SubRip) subtitles. I wish to simply cut out (stream-copying) sections of these file(s), cutting at I-frames of course, which Avidemux is a brilliant tool for making it possible for me to see what I'm doing (due to it's WYSIWYG style) and yeah, pull through. The subtitles are unfortunately lost during the process.

I can use FFmpeg and "-c copy -map 0" to include all streams, but pin-pointing the exact points for cutting is definitely more of a PITA this way, so I'm trying to figure out some sort of hack or workaround to make my task more easy. Avidemux support would therefor be a blessing.

eumagga0x2a

Quote from: Gew on June 20, 2024, 09:25:06 AMIs there ANY chance of future implementation of subtitle handling, the way this thread starter suggests?

The same second someone bothers to write the necessary code, to submit a pull request, as soon as code gets reviewed and merged. Someone should do the first step (as I obviously cannot do it in near future). This feature is close to the top of the heap of nice-to-haves, no argue about that.