DroidDeck/docs/development/boot-movies.md

Boot movies

Settings → Boot movie has four tabs.

• Installed: "Browse" lists every movie Steam can play: DroidDeck's two, plus every .webm in Steam's config/uioverrides/movies folder (imported, installed from SteamDeckRepo, or put there by Steam). The list is re-read every two seconds, so a movie picked or removed inside Steam shows up, and a movie picked inside Steam becomes the choice.
• Import: the same importer as before (copy, remux or on-device transcode to VP8/Opus). The result is written into Steam's movies folder, so Steam lists it as well.
• SteamDeckRepo: browses https://steamdeckrepo.com/api/posts (sort, device, search, page; 12 posts a page). Installing downloads the movie through the site's own download address and imports it like any other movie. Tapping a thumbnail plays the movie from the site (MediaPlayer on a TextureView) before it is installed. The site does not say how many pages there are, so the last page is found by asking for pages until one comes back empty or short; the pager shows the current page (tap it to type another), three pages either side, the first and last page numbers, and Previous and Next. Search and "go to page" use a small dialog with the app's native text field (AdbTextField), because that field is what brings up the Android keyboard in these screens.
• Sound: sound on/off, volume, and how many seconds of the movie play. Anything other than full volume and the whole movie is built into files/boot-movie/variants (audio re-encoded as Opus, video copied) and staged instead.

Imported and installed movies are kept in files/boot-movie/library (with their list, files/boot-movie/movies.json) and copied into Steam's movies folder, so resetting the Linux runtime does not lose them; the copy is put back when it is missing. The list is changed under one lock, so imports at the same time cannot overwrite each other. Every movie in Steam's custom movies folder (config/uioverrides/movies) can be removed after a confirmation, whether DroidDeck put it there or it was added by hand or by Steam's own picker. Steam's own three startup movies (deck_startup, oled_startup, startup_machine in steamui/movies) and points shop movies (any other .webm below Steam's config, userdata, appcache and steamui folders, plus whatever path StartupMovie.LocalPath names) are listed as Steam movies, adopted when picked in Steam, and never deleted. Bought movies live in config/communityitemscache/startupmovies/<item number>_<hash>.webm; their titles come from the GetStartupMovies list in userdata/<id>/config/localconfig.vdf. Other videos in steamui/movies are not startup movies and are not listed. Only one processed copy (volume or length change) is kept in files/boot-movie/variants; a volume that cannot be applied plays without sound rather than louder, and plays nothing if that fails too. Covers are cached in files/boot-movie/thumbs. Steam reads its startup movie from the StartupMovie section inside the Customization section of config/config.vdf (MovieID, and LocalPath relative to config; a Points Shop movie has its item number as MovieID). The StartupMovie section under Software/Valve/Steam is where older clients read it, and DroidDeck writes both. Selecting a movie here sets bootMovieApplyNext, so the next session stages the movie as bigpicture_startup.webm and points both sections at it, over a movie Steam had picked; otherwise a movie picked in Steam is left alone and taken over as the choice here without being staged over Steam's own setting. Settings > Boot movie > Installed has a report button that writes what Steam and DroidDeck know to Download/DroidDeck/boot-movie-report.txt; it only shows while Debugging tools is on. A movie larger than 1920x1080 (4K and the like) is never copied or remuxed as it is: import and staging always convert it (the converter scales to at most 1280x720), because such movies have made Steam crash while it starts.