Subtitle file is not deleted after being embedded

[35609902357]

Embedding subtitles in the video and also keeping the file is pointless and it results in 2 identical tracks for the same video.

The default behavior of youtube-dl is to keep the file if not embedded and delete it if embedded, this is smarter because the -k flag can be used if someone wants to embed and also keep the file, but there is no flag to automatically remove the file once embedded.

Maybe adding a flag like --keep-subs-file would solve the problem for those few users who might want both, but the default should be what youtube-dl does, keep the file if external subs or embed and delete.

[pukkandan]

Embedding subtitles in the video and also keeping the file is pointless and it results in 2 identical tracks for the same video.

Just because you don't have a use-case for it doesn't mean it is pointless

but the default should be what youtube-dl does, keep the file if external subs or embed and delete.

If you are using --write-sub --embed-sub, it means you want to both keep the subs in disk and embed it. You may also seperately use --embed-subs to embed the subs or --write-subs to keep the file. This is consistent with how --write/embed-thumbnails work

The default behavior of youtube-dl is to keep the file if not embedded and delete it if embedded

While this is not the "right" behaviour imo, you are right that this is how upstream works. So I will make a comapt-option to go back to this. But the default will be kept as the current behaviour

this is smarter because the -k flag can be used if someone wants to embed and also keep the file, but there is no flag to automatically remove the file once embedded.

It is not the same. -k also keeps around many other files like the thumbnail, unmerged streams etc

[pukkandan]

For reference, here's the differences:

youtube-dl

Option	Behaviour
--write-subs	Write normal sub to disk
--write-auto-subs	Write auto sub to disk
--write-subs --write-auto-subs	Write a normal/auto sub to disk
--embed-subs	Do nothing
Nothing	Embed normal sub and keep it in disk
Nothing	Embed a normal/auto sub and keep it in disk
--write-subs --embed-subs	Embed normal sub and delete
--write-auto-subs --embed-subs	Embed auto sub and delete
--write-subs --write-auto-subs --embed-subs	Embed a normal/auto sub and delete

yt-dlp

Option	Behaviour
--write-subs	Write normal sub to disk
--write-auto-subs	Write auto sub to disk
--write-subs --write-auto-subs	Write a normal/auto sub to disk
--embed-subs	Embed normal sub and delete
--write-subs --embed-subs	Embed normal sub and keep it in disk
--write-subs --write-auto-subs --embed-subs	Embed a normal/auto sub and keep it in disk
--write-auto-subs --embed-subs	Embed auto sub and delete
--write-subs --write-auto-subs --embed-subs --compat-options no-keep-subs	Embed a normal/auto sub and delete (#826 tracks adding a proper option for this)

Edited to be more comprehensive

[35609902357]

@pukkandan

Just because you don't have a use-case for it doesn't mean it is pointless

You arbitrarily decided to change a long standing default behavior because one user asked for this in an unrelated issue, no proper issue was ever open about this.

Changing that default behavior makes the transition from youtube-dl to yt-dlp and viceversa a pain because it breaks years old config files and requires to pay extra unneeded attention when using one project or the other.

Not only that, but those who embed --all-subs will have a hard time having left hundreds of files around.

Not only that, but it's also lacking. For example, I want to automatically embed subs if they are present, if there is no subtitles track I want to embed automatically generated subs. In youtube-dl I would go with --write-subs --write-auto-subs --embed-subs, yt-dlp leaves around files, even if there are only auto generated subs. Since the only option to differentiate between subs types are --write-subs and --write-auto-subs, yt-dlp makes it impossible to have the old behavior.

--embed-subs being a post-process option should naturally work on the file generated by the previous option, then all files are deleted after the post-process, for those who need one or many files to be kept there's the -k flag.

There is no point having internal and external tracks for the large majority of users. Even if someone might need both for some edge case, there's no point in making it the default instead of creating a --keep-subs option to integrate their need.

From the Readme (emphasis mine):

The main focus of this project is adding new features and patches while also keeping up to date with the original project

Changing defaults goes against the purpose of this project.

[pukkandan]

You arbitrarily decided to change a long standing default behavior because one user asked for this in an unrelated issue, no proper issue was ever open about this.

It is youtube-dl's handling of --embed-subs that is inconsistent with their own handling of the similar option --embed-thumb. When this disparity was pointed out to me, I changed this at my discretion. This should be considered this a bug in youtube-dl since this inconsistent behaviour is never documented anywhere and is therefore counter-intuitive and most probably unintentional.

Not only that, but those who embed --all-subs will have a hard time having left hundreds of files around.

--all-subs is deprecated. You should be using --sub-lang all. see this. While I keep most deprecated options still working, they will obviously be more limited in their capability than their recommended counterparts

Changing that default behavior makes the transition from youtube-dl to yt-dlp and viceversa a pain because it breaks years old config files and requires to pay extra unneeded attention when using one project or the other.

I have no intention of maintaining perfect compatibility with years old youtube-dl config files out of the box - especially if they are using such undocumented "features". If you really want yt-dlp to work as close to youtube-dl as possible, you should use --compat-options youtube-dl. There are also many other changes that have been made to the default behavior as documented here

It is true that I had failed to document how --embed-subs behaved differently than youtube-dl. But since b51d2ae, it is documented and I have also added the option --compat-options no-keep-subs to go back how youtube-dl handled it.

For example, I want to automatically embed subs if they are present, if there is no subtitles track I want to embed automatically generated subs. In youtube-dl I would go with --write-subs --write-auto-subs --embed-subs, yt-dlp leaves around files, even if there are only auto generated subs. Since the only option to differentiate between subs types are '--write-subsand--write-auto-subs`, yt-dlp makes it impossible to have the old behavior.

This is a fair point. Currently the only way to achive this is by using the compat-option. I will see what can be done to improve this

--embed-subs being a post-process option should naturally work on the file generated by the previous option, then all files are deleted after the post-process, for those who need one or many files to be kept there's the -k flag.

This is clearly not the intended use of -k

     -k, --keep-video                Keep the intermediate video file on disk after post-processing

Instead of changing how --embed-subs work, I could have instead changed how -k works with --embed-thumb, but that only serves to further limit the functionality

The main focus of this project is adding new features and patches while also keeping up to date with the original project
Changing defaults goes against the purpose of this project.

Keeping up-to-date means that upstream changes will be pulled to yt-dlp in a timely manner, not that I won't make any changes

[35609902357]

I have also added the option --compat-options no-keep-subs to go back how youtube-dl handled it.

Thanks for the fix @pukkandan. For simplicity you should allow compatibility options as standalone flags too (for example allow both --compat-options no-keep-subs and --no-keep-subs to do the same thing, same with the other options).

This should be considered this a bug in youtube-dl

If you really think so you should open an issue in youtube-dl project to express your reasons.

[database64128]

Not only that, but it's also lacking. For example, I want to automatically embed subs if they are present, if there is no subtitles track I want to embed automatically generated subs. In youtube-dl I would go with --write-subs --write-auto-subs --embed-subs, yt-dlp leaves around files, even if there are only auto generated subs. Since the only option to differentiate between subs types are --write-subs and --write-auto-subs, yt-dlp makes it impossible to have the old behavior.

I think this issue should be kept open until this is resolved.

[pukkandan]

It is now possible using the compat option. But I do agree that it should be possible without it. Please open a new issue

[database64128]

Opened #826 to track it.

[PacoH]

BTW using just --embed-subs left behind the vtt file in the folowing case. Adding --compat-options no-keep-subs fixed it. I don't know if this is case-specific or not. Version 2021.10.10. OS X installed with pip.

yt-dlp --no-check-certificate -v -i -c --no-mtime --no-playlist --sub-lang en,en-US,en_US,cs,zh-CN --embed-subs -o "%(title)s %(resolution)s %(format_id)s %(vcodec)s %(acodec)s.%(ext)s" <url>