Mirroring your screen throws away most of what makes a 4K HDR film worth watching. The picture is captured from your desktop and encoded again. To keep the quality, the original video stream has to reach the TV.
How Driftcast does it
Driftcast is a free Mac app that sends the original stream wherever the device supports it, even from an MKV.
| Device | Largest picture | HDR |
|---|---|---|
| Apple TV, AirPlay 2 TVs | 4K | Yes |
| Google TV Streamer | 4K | Yes |
| Chromecast Ultra, Chromecast with Google TV, TVs with Cast built in | 4K | Yes |
| Chromecast HD | 1080p | Yes |
| Chromecast 1st to 3rd generation | 1080p at 30 fps | No |
If the device can’t take it
- HDR on a device without HDR is tone-mapped to normal range, so the picture doesn’t look washed out.
- A picture too big for the device is scaled down to what it can show.
- Both happen on your Mac’s GPU. In one test, converting a 4K HEVC clip to 1080p took 6.45 seconds of CPU time with software decoding and scaling, and 0.19 seconds with the whole job on the GPU.
Passing Dolby Vision through depends on the TV: some show the Dolby Vision layer and others only the HDR10 base.
An honest note: Driftcast’s Chromecast support follows Google’s documentation, and its streams have been checked in Apple’s player, but it hasn’t been tried on a real Chromecast yet. If you own one, please say how it went, working or not.
Get Driftcast
Driftcast is free and open source, with no account, trial or ads. It needs macOS 13 Ventura or later, on an Apple silicon or Intel Mac.
Download Driftcast · Source code on GitHub · Everything it plays
More guides
- How to cast MKV files to Chromecast from a Mac
- How to play MKV files on Apple TV from a Mac
- How to send any video from a Mac to a Samsung or LG TV
- How to get subtitles on Chromecast from a Mac
- How to play DTS audio on Chromecast from a Mac
- How to cast 4K HDR video from a Mac
- A free Airflow alternative for Mac