The goal is to Direct Play all media. This means the container, video, audio and subtitles are all compatible with the client. If the media is incompatible for any reason, Jellyfin will [convert the media](http://howto-pages.org/ffmpeg/) to a format that the client can process. Direct Stream will occur if the audio, container or subtitles happen to not be supported. If the video codec is unsupported, this will result in video transcoding. Subtitles can be tricky because they can cause Direct Stream (subtitles are remuxed) or video transcoding (burning in subtitles) to occur. This is the most intensive CPU component of transcoding. Decoding is less intensive than encoding.
🔶=Support depends on device and/or settings.<br />
⚠️=Software Decode Only.<br />
✅=Fully supported (Hardware support with software fallback).<br />
<br />
This table shows the support status of **recent** client software and OS versions. Legacy versions may differ in support. Remuxing due to container compatibility is considered fully supported for this table. <br /><br />
<sup>6</sup>AV1 is enabled by default for Swiftfin (VLCKit). AV1 is disabled by default for Native (AVKit). Enabling AV1 may result in a poor experience for older devices.
<sup>7</sup>Windows requires the [HEVC video extension from Microsoft Store](https://apps.microsoft.com/detail/9nmzlz57r3t7). Linux requires system ffmpeg for support.
Some Linux distributions provide a Firefox package that does not have H264 support, causing transcoding to be required. You may need to install additional packages on these system. The most obvious symptom is Jellyfin attempting to transcode to VP9.
HDR is only supported on a very limited range of devices:
- iOS Devices with an HDR capable internal display can display HDR content when using a browser or the Jellyfin iOS App (not Swiftfin) as long as the codec is supported by the client. All of them support HEVC and VP9, while AV1 is supported on newer devices. HDR10, Dolby Vision and HLG are supported.
- Android devices running either the official Android App or using Chrome can display HDR content if the device supports HDR and the source format. Format support depends on device.
- Macs running macOS that support HDR can play HDR content when using Safari, Chrome or Firefox on an HDR capable display as long as the source codec is supported. Safari has the most complete support, including HDR10, Dolby Vision (including P5) and HLG. Chrome and Firefox only support HDR10. Chrome supports HDR10 on HEVC, VP9 and AV1. Firefox only supports HDR on VP9 and AV1 content. Please refer to [the list of Macs that support HDR](https://support.apple.com/en-us/102205) to check if your device is supported. On non-Apple displays, other HDR formats will be tone-mapped to HDR10 by the client device.
- Windows PCs with an HDR display with HDR enabled in the settings using Edge or Chrome. Dolby Vision only works in Edge and requires [the Dolby Vision add-on from the Microsoft Store](https://apps.microsoft.com/detail/9pltg1lwphlf) to be installed. Edge generally produces better colors than Chrome when playing HDR content.
- WebOS devices (Newer LG Smart TVs) running the official WebOS client supports HDR. However, [mkv containers are known to cause issues](https://github.com/jellyfin/jellyfin-web/issues/4678). Please enable the force remux mkv to mp4 option in the client settings as a workaround.
- Some Chromium-based browsers on Linux will attempt Client-side HDR to SDR tonemapping. This generally looks very bad. There will be no server side involvement when this is happening.
Devices not listed above do not support HDR on any official client. Any HDR content will have to be converted to SDR by the server for proper playback on these clients. For more info, please refer to our [tone-mapping documentation](/docs/general/post-install/transcoding/#hdr-to-sdr-tone-mapping)
If the audio codec is unsupported or incompatible (such as playing a 5.1 channel stream on a stereo device), the audio codec must be transcoded. This is not nearly as intensive as video transcoding.
Subtitles can be a subtle issue for transcoding. Containers have a limited number of subtitles that are supported. If subtitles need to be transcoded, it will happen one of two ways: they can be converted into another format that is supported, or burned into the video due to the subtitle transcoding not being supported. Burning in subtitles is the most intensive method of transcoding. This is due to two transcodings happening at once; applying the subtitle layer on top of the video layer.
<sup>1</sup>VTT are supported in an <a href="https://helpx.adobe.com/adobe-media-server/dev/webvtt-subtitles-captions.html">HLS Stream</a>.
<br />
<sup>2</sup>DVB-SUB <a href="https://forum.videohelp.com/threads/261451-Difference-between-SUB-and-IDX-file">(SUB + IDX)</a> is another name for VobSub files.
<sup>3</sup>EIA-608/708 subtitles are embedded in private channels (channel 21) in a MPEG video codec. EIA-608 are standard CC subtitles with the black bar background, while EIA-708 are typically SDH.
### Types of Subtitles
There are many variations of subtitles. Closed, open, burned-in, forced, SDH, and CC are among the common types of subtitles. The format (such as SubRIP or VobSUB) does not matter for the type of subtitle.
#### Closed Subtitles
This is the generic name for subtitles that can be turned on or off. This can be Forced, SDH, CC or normal subtitles.
#### Burned-in
Open subtitles (also known as burned-in subtitles) are subtitles that have been permanently placed in the video and cannot be turned off. Open subtitles are the most common type of subtitles, where the subtitles are part of the video stream and cannot be toggled on or off.
SDH and CC are subtitles for the Deaf and Hard of Hearing. They include extra content such as background noises. SDH and CC are not defined by a specific type of subtitle, just by their intent. If using an OTA Tuner and DVR, the subtitles will be embedded into the video and transcoding them before extracting the subtitles will destroy the subtitles.
"Forced subtitles are common on movies and only provide subtitles when the characters speak a foreign or alien language, or a sign, flag, or other text in a scene is not translated in the localization and dubbing process. In some cases, foreign dialogue may be left untranslated if the movie is meant to be seen from the point of view of a particular character who does not speak the language in question." - [Wikipedia](https://en.wikipedia.org/wiki/Subtitles#Categories)
### Extracting Subtitles
To extract subtitles, the following commands can be used. The section `0:s:0` means the first subtitle, so `0:s:1` would be the second subtitle.
#### SSA/ASS Subtitles
```bash
ffmpeg -dump_attachment:t "" -i file.mkv -map 0:s:1 -c:s ass extracted-subtitle.ass
```
#### Recorded OTA Content
Content recorded OTA will typically have subtitles [embedded](https://aberdeen.io/blog/2009/06/18/the-basics-of-608-vs-708-captions/) into the video codec itself. These subtitles are typically EIA-608 for analog and EIA-708 for digital.
Text-based subtitle formats require fonts to render properly. Please refer to [Fonts](/docs/general/administration/configuration#fonts) for how to install them.
If the container is unsupported, this will result in remuxing. The video and audio codec will remain intact but wrapped in a supported container. This is the least intensive process. Most video containers will be remuxed to use the HLS streaming protocol and TS containers. Remuxing shouldn't be a concern even for an RPi3.
<sup>5</sup>WebM and OGG have limited codec support (by design), refer to <a href="https://developer.mozilla.org/en-US/docs/Web/Media/Formats/Containers#WebM">this</a> for WebM and <a href="https://developer.mozilla.org/en-US/docs/Web/Media/Formats/Containers#Ogg">this</a> for OGG.
<sup>8</sup>MKV support in Firefox is currently disabled in Jellyfin, as there are significant issues making it unusable for Jellyfin. [1](https://bugzilla.mozilla.org/show_bug.cgi?id=2000420) [2](https://bugzilla.mozilla.org/show_bug.cgi?id=1991746)
