How to extract auto-generated and auto-translate closed captions? about youtube_explode_dart

[Hexer10]

You can extract them it's just that you can't directly.
To explain it clearly: Youtube only provides some subtitles tracks by default (those uploaded by the user and autogenerated ones, iirc they are in the language of the video), the translation of the tracks is not available right away and you need to generate their url with the code I posted before:

var manifest = await yt.videos.closedCaptions.getManifest('WOxr2dmLHLo');
var trackInfo = manifest.getByLanguage('en', autoGenerate: false, format: ClosedCaptionFormat.srv3); // Or manifest.tracks.first if you just want to get an available track.
if (trackInfo != null) {
    var subtitles = await yt.videos.closedCaptions.getSubTitles(trackInfo.autoTranslate('vi'));
}

PS: I'm only now noticing that I posted the wrong code in the previous comment, sorry

[Hexer10]

Fetching auto-translated closed captions is not yet support, I'm planning to implement it in the coming days

[Hexer10]

This was implemented see the unit tests to have an idea on how to implement this:

youtube_explode_dart/test/closed_caption_test.dart

Lines 14 to 52 in a9275af

	test('Get closed captions of a video', () async {
	var manifest = await yt.videos.closedCaptions.getManifest('WOxr2dmLHLo');
	expect(manifest.tracks, isNotEmpty);
	});
	test('Get closed caption track of a video', () async {
	var manifest = await yt.videos.closedCaptions.getManifest('WOxr2dmLHLo');
	var trackInfo = manifest.tracks.first;
	var track = await yt.videos.closedCaptions.get(trackInfo);
	expect(track.captions, isNotEmpty);
	});
	test('Get closed caption track at a specific time', () async {
	var manifest = await yt.videos.closedCaptions
	.getManifest('WOxr2dmLHLo', autoGenerated: false);
	var trackInfo = manifest.getByLanguage('en');
	var track = await yt.videos.closedCaptions.get(trackInfo.first);
	var caption =
	track.getByTime(const Duration(hours: 0, minutes: 1, seconds: 48));
	expect(caption, isNotNull);
	expect(caption.parts, isEmpty);
	expect(caption.text,
	'The second way to add subtitles is the one\nwe always use.');
	});
	test('Get auto-generated closed caption track at a specific time', () async {
	var manifest = await yt.videos.closedCaptions
	.getManifest('ppJy5uGZLi4', autoGenerated: true);
	var trackInfo = manifest.getByLanguage('en');
	var track = await yt.videos.closedCaptions.get(trackInfo.first);
	var caption =
	track.getByTime(const Duration(hours: 0, minutes: 13, seconds: 22));
	var captionPart = caption.getPartByTime(const Duration(milliseconds: 200));
	expect(caption, isNotNull);
	expect(captionPart, isNotNull);
	expect(caption.text, 'how about this black there are some');
	expect(captionPart.text, ' about');
	});

[tuanbs]

Hello, thanks for this. The auto-generated works fine, but the auto-translate is not working. Hope it's supported in the near future.

[Hexer10]

Seems like youtube implement some changes recently now the request must include some kind of specific query parameter, I'll look into this when I have time

[Hexer10]

It now should be fixed please read the changelog and try again

[tuanbs]

Hello, thanks for the update. But it's still not working with auto-translate track. For ex, I tried the following test and got the null result:

var manifest = await yt.videos.closedCaptions.getManifest('WOxr2dmLHLo');
var trackInfo = manifest.tracks.firstWhere((element) => element.language.code == 'vi', orElse: () => null);
if (trackInfo != null) {
    var subtitles = await yt.videos.closedCaptions.getSubTitles(trackInfo);
}

I got null value for trackInfo. But as you can see in the attached image, the video has Vietnamese (vi) auto-translate track:

[Hexer10]

Youtube does not provide autotranslated tracks by default you first need to get a track provided by youtube, and then autotranslate it:

var manifest = await yt.videos.closedCaptions.getManifest('WOxr2dmLHLo');
var trackInfo = manifest.getByLanguage('en', autoGenerate: false, format: ClosedCaptionFormat.srv3); // Or manifest.tracks.first if you just want to get an available track.
if (trackInfo != null) {
    var subtitles = await yt.videos.closedCaptions.getSubTitles(trackInfo);
}

[tuanbs]

@Hexer10 Does that mean youtube_explode_dart cannot extract the auto-translate track? I think it should be possible because I see Youtube-dl can extract it.

[tuanbs]

@Hexer10 Awesome. Finally I'm able to get the auto-translate CC thanks to your code. Thank you very much. Please keep evolving this plugin as you guys are doing amazing job. 🥇