Video Gamma & Sharpness — brighten dark scenes by Дмитрий

A dark scene and you can't make anything out? Raise the gamma: shadows and midtones get lighter while black and white stay put, so the picture doesn't turn gray. Brightness, contrast, saturation and sharpness are there too.

Click the icon and pick a preset (Dark scene, Washed out, Sharper or Dim) or move the sliders. While the filter works, the icon shows "on". Alt+Shift+G turns it on and off without the mouse.

WHAT'S DIFFERENT
• No access to all sites. The add-on sees nothing until you click its button or press Alt+Shift+G, and works only in that tab.
• Gamma, not just brightness: shadows get lighter, highlights don't wash out.
• Sharpness without stutter: the graphics card draws the filter, so even 4K plays smoothly in fullscreen.
• Values are remembered per site. Each tab has its own filter.
• Fullscreen, theater mode, going to the next video within the site: the filter stays.
• The site's player is left alone: its buttons, volume and speed stay as they were.

WHERE IT WORKS
Tested on YouTube (and Shorts), VK Video, Rutube, Twitch, Vimeo, and the players of Deutsche Welle and Wikimedia Commons.
• A player embedded from another site (say, YouTube inside an article) is off-limits to the add-on; the popup says so. Open the video on its own site.
• DRM-protected video with standard protection gets the filter. On paid services with stricter protection it may not work.
• After a page reload you may need to click the button or press Alt+Shift+G again; the site's values are kept.
• The browser's own pages (about:) are closed to all add-ons.
• Only the way the video is shown changes; files and recordings don't.

PRIVACY
• No ads, analytics, sign-up or servers.
• The add-on doesn't read page text or keep a history. It keeps the values for the sites where you changed them, on this device.
• Video is never recorded or sent anywhere.

English and Russian interface, light and dark theme.