WebOne is able to convert YouTube videos for play back them on older PCs.

Prerequisites

YouTube video processing feature requires Yt-dlp (Youtube-dl) and FFmpeg programs.

• On Linux when installing WebOne from deb package, ffmpeg and yt-dlp are recommended packages, and are installing automatically except if WebOne is installed with --no-install-recommends argument.
• On Linux when installing WebOne from rpm package, install ffmpeg and yt-dlp packages manually.
• On Windows, get them here: yt-dlp.exe, ffmpeg.exe. Or use Full and Full Self-Contained builds of WebOne, as they're containing all this.
• On macOS, get them here: Yt-dlp, FFmpeg.

Playback via Retro Online Video Player

You can open http://proxy:port/!player/ page and watch videos through a web browser. This allows playing YouTube videos (but not live streams) even on slow PCs which accepts only MPEG or similar codecs. The toolbar on the page operates video options.

• Video: URL of the video. YouTube is not only service supported, you may try some other popular sites too.
• Format: Container for the video. It must be supported by media player, used to play the video. In "Embed" mode the player is selecting automatically depending on video format.
• Video options: Codec and resolution for video track. See notes below. The optimal choose rely on system performance and installed set of codecs.
• Audio options: Codec and stereo/mono switch for sound track(s). Monophonic videos plays on weaker systems smoothly.
• Mode: Select here the player used to display the video.
  • Embed
    • Let's Web browser select how to display the content.
    • Supported by almost all browsers for AVI, ASF, MPEG TS, Flash content types.
    • Best for Flash Player.
  • WMP
    • Use Windows Media Player 6.4-12.0 plug-in for playback. Compatible with either Microsoft Internet Explorer and Mozilla (with WMP NPAPI plug-in installed).
    • It's a good idea to have K-Lite Codec Pack been installed, as it installs full support for almost all codecs even with video card acceleration (DXVA).
  • VLC
    • Use VLC Media Player plug-in for playback. The plug-in supports many formats and containers, but is slow and have no playback controls at all. Last is limitation of VLC.
    • Works on all systems with VLC Media Player.
  • WinMedia
    • Internet Explorer only. Use Windows Media Player Control to play the video. Requires Windows Media Player 8/9/10/11/12 and MSIE.
  • NetShow
    • Internet Explorer only. This is same as WinMedia, but intended for older versions of the ActiveX control. It works with NetShow 2.x and Windows Media Player 6.0-6.4. However, WMP 9 and newer are not supported.
    • Limitations: consider use ASF format.
    • Limitations: Old versions of Microsoft NetShow Player don't display controls by default (this can be changed by right click on player box).
  • DynImg
    • Internet Explorer only. Experimental support for MSIE's Dynamic Images. Requires at least Internet Explorer 2.0 up to 6.0. Seems that requires some MCI ActiveMovie codecs installed on the system (not newer DirectShow ones).
    • Limitations: video format must be AVI. Which codecs are supported is unknown. Untested well.
  • HTML5
    • Best for browsers from 2010 and newer. Use the built-in video player of your web browser (Firefox 3.5+, Opera 11.5+, Safari 4.0+, Chrome 4+, Internet Explorer 9+).
    • Limitations: only Ogg and, sometimes, WebM formats are supported.
  • Link
    • Get a direct link to converted video. This is useful if you need to download the video file, and play it from hard disk.
    • You can copy the link, and add custom parameters to it to set converting options if need.
  • File
    • Similar to Link mode, but automatically starts the download. Note that on video download errors you get the readable error message.
    • Sometimes can help with playing Flash videos.

Codec and format notes

Format	Support(default)	Support(available)	Notes	Best for
AVI	Embed/WMP/NS/VLC/Img	?		Download
MPEG1	VLC	WMP 6+
MPEG2	VLC	WMP 6+
MPEGTS	VLC/WMP 12	WMP 9+		Windows Media Player 12
ASF	Embed/WMP/NS/VLC	all		Windows Media Player 6.x and NetShow Player
Ogg	HTML5	VLC	Supports only Theora video and Vorbis (stereo) audio codecs	HTML5 playback in Firefox
WebM	HTML5	VLC	Supports only VP8, VP9 video and Vorbis (stereo), Opus audio codecs	HTML5 playback in Chrome
Flash	IE, Netscape, Mozilla, Opera	?	Supports only MJPEG video and MP3 audio codecs	Playback in Netscape 3.0/4.x, Mozilla, IE 5.0, Opera 5, non-Windows systems

Codec	Support(default)	Support(available)	Notes	Best for
MPEGs	VLC	WMP	Good on slow machines	Retro PCs up to Pentium-4/AMD K8
H264	WMP 12, VLC	WMP	Good on slow machines	Retro PCs from Core2/Athlon64 and up
H263	NetShow, WMP, VLC	?	Support only 128x96, 176x144, 352x288, 704x576 sizes	Pre-installed on Windows 9x, NT
Video 1	NetShow, WMP, VLC	?	Support only 4:3 video format	Pre-installed on Windows 9x, NT
WMV v7	WMP 7+, VLС	WMP 6.x		Great for Windows Media Player 6
MJPEG	VLС	may be WMP		Great for Macromedia Flash-based player

Codec	Support(default)	Support(available)	Notes	Best for
Vorbis	HTML5 browsers	VLC	Stereo sound format is only supported	Firefox 3.5/3.6/4+, SeaMonkey 2.x, etc

Quick access

Add &play=1 or &dl=1 to end of the YouTube page address. Then it will be redirected to ROVP.

Bookmarklet

To simplify, you may add a button on bookmark toolbar: javascript:document.location+='&play=1' (create a bookmark with this URL). One click, and YouTube page will be changed to ROVP.

Configuring

You may add all yt-dlp and ffmpeg options as URL arguments for video file download page (not the player itself). Default options are set in WebOne's configuration files.

The most wanted options are bitrate/quality change. They are setting by specifying ffmpeg options, which can be googled in ffmpeg manuals for each codec.

Default downloading/converting options (used by ROVP) are set up by WebVideoOptions(https://github.com/atauenis/webone/wiki/Configuration-file#webvideooptions-section) section of configuration file.

Troubleshooting

Sometimes you may get an unplayable video file. This may be caused by any reason.

1. A file may be incompatible with installed player (this can be tested by downloading converted file, copy on newer machine, and play it on it - an success will mean that you need to try another codec/format or try another player software, codec packs, etc).
2. There are may be some problems on YouTube side (will result in a error message inside video file, then it is few dozen bytes long instead of megabytes).
3. Sometimes there are may be issues related to video converter. In this case file will be incomplete (or even empty), and ffmpeg errors will be displayed on server console. The only way to see ffmpeg errors is to run WebOne inside a Terminal/Command Prompt window. They are not stored to log file due to limitations of ffmpeg.
4. YouTube can ban used Yt-dlp version or change something in API. They're sometimes inventing new things in violation of rights of humans who are skipping tons of context advertisements available only on modern YouTube Web site. In this case try to update Yt-dlp (probably newer version will be stronger).

Notes on older WebOne versions

WebOne 0.9-0.14 used external shell script, yt.bat and yt.sh, which worked similar to ROVP, but without ability to set custom options and without GUI. Any old instructions or blog posts about the script(s) are not applicable to WebOne 0.15 and up.

Playback via ViewTube

Main article: Using with ViewTube.

In 2019 I've developed a fork of sebaro's ViewTube user script (for Greasemonkey/Tampermonkey), which allowed viewing and downloading YouTube videos through WebOne and FFmpeg. Currently YouTube pages code has been changed, and my fork no longer works. Most likely, I'll not update it to work with modern YouTube page code.

The original ViewTube also no longer works in Firefox 3.5/Opera 11.6 and similar browsers. So currently it is not possible to watch YouTube videos via WebOne using this user script.