[Vbox7,DASH] Fix and improve extraction with DASH manifests using range and base URL

[dirkf]

Boilerplate (own/yt-dl/yt-dlp code, bug fix/improvement)

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Before submitting a pull request make sure you have:

• Searched the bugtracker for similar pull requests
• Read adding new extractor tutorial
• Read youtube-dl coding conventions and adjusted the code to meet them
• Covered the code with tests (note that PRs without tests will be REJECTED)
• Checked the code with flake8

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• I am the original author of this code and I am willing to release it under Unlicense, except for code adapted from PRs to this project and from yt-dlp, where this or the below has already been asserted
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What is the purpose of your pull request?

• Bug fix
• Improvement
• New extractor
• New feature

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Description of your pull request and other information

This PR has three parts.

1. Back-port DASH subtitle extraction from yt-dlp, included to avoid redundant changes when implementing subtitle extraction from manifest URLs or when porting these changes downstream.
2. Support range-based DASH manifests, based on defunct PR support byte range for dash mpd #30279 from former GH user kikuyan (thx, fixes [common] _parse_mpd_formats doesn't handle range-based segment lists #13784, fixes Video from MPEG-DASH stream much larger than same video from HLS stream #30235), adapted to

• match the above
• use new APIs
• properly resolve BaseURLs.

3. Fix and improve extraction for site vbox7.com, based on defunct PR [extractor/vbox7] improve extraction #29680 from former GH user kikuyan (thx, fixes Vbox7.com broken #14685, fixes cant download from vbox7 #26063, fixes can't extract video from vbox7 #27575, resolves Urgent - Vbox7 support needs to be fixed, so that archivists can save nearly all its' videos before they're permanently lost on Feb 22 #32701). The site normally offers range-based DASH, although combined AV mp4 formats are also available.

[stdakov]

How can I manually install it and test it?

[dirkf]

Supposing that you have a supported Python installation, git clone the source repo; then go into the youtube-dl directory and use python -m youtube_dl as the youtube-dl command (where python is what you type to run Python).

Otherwise you can manually replace the changed files in an installation from this repo's master or from the latest nightly build. You may need to become admin to do that: if so, also run youtube-dl --version as admin to ensure that cached byte-code files are updated (or the system will ignore the new sources in favour of the previous compiled versions).

[stdakov]

Supposing that you have a supported Python installation, git clone the source repo; then go into the youtube-dl directory and use python -m youtube_dl as the youtube-dl command (where python is what you type to run Python).

Otherwise you can manually replace the changed files in an installation from this repo's master or from the latest nightly build. You may need to become admin to do that: if so, also run youtube-dl --version as admin to ensure that cached byte-code files are updated (or the system will ignore the new sources in favour of the previous compiled versions).

it works for downloading videos and m4a
Thank you!

[dirkf]

There are some extra features in the yt-dlp PR that can be added, but this can probably be merged as-is for now.