Castmate
Why casting a Chrome tab is laggy and blurry
What tab casting actually does, why it looks worse than the video, and what to do about it.
When you choose "Cast tab", your computer records the tab, compresses it into a live video and sends that over Wi-Fi. The TV never sees the original video, only that recording of it.
Why it looks and feels bad
- Quality: the video is compressed a second time, on the fly, at a limited bitrate, so fine detail and fast motion suffer.
- Lag: encoding and sending take time, so sound and picture run behind what's on your screen.
- Wi-Fi: the laptop has to send everything to the TV, so a weak connection shows up straight away as stutter.
- Heat and battery: encoding keeps the laptop's processor busy, and the laptop has to stay on and awake.
What helps while mirroring
- Move the computer closer to the router, or use 5 GHz Wi-Fi or Ethernet.
- Close other heavy tabs.
- Lower the video's quality in the player: a lower source can look better than a high one that stutters.
The real fix: don't mirror
Give the TV the video's own address, and it fetches the stream by itself in the original quality, with the laptop out of the way. Players with a Cast button do this already. For the others, see cast a video from any website; Castmate for Chrome finds the stream and casts it in one click. It can't do this for DRM-protected services, and some sites refuse the TV.