Casting vs screen mirroring from a Windows PC
Published 28 October 2026 · 6 min read
“Cast” and “mirror” are often used as if they meant the same thing. They do not. Screen mirroring shows your whole screen on the TV. Casting sends one video to the TV and lets the TV play it. Both are useful, and they are good at different things.
Screen mirroring: your desktop, on the TV
Screen mirroring is built into Windows. Press Windows key + K, or open Cast from the quick settings, and Windows lists the TVs and adapters nearby that support wireless display (the Miracast standard). Pick one, and the TV shows what your PC screen shows.
To do that, Windows captures the screen many times a second, compresses it into a live stream and sends it over the air. That is why mirroring works with anything: a slideshow, a web page, a photo album, a game. It is also why a film can look softer than it does on the PC, or fall behind on a busy network: the video is decoded on the PC, shown on the desktop, captured again and re-compressed before the TV sees it.
Casting: the video itself
Casting skips the desktop. AIX Player finds the televisions on your home network, asks the one you pick what it can play, and sends it the video stream. The TV decodes the film itself. Nothing on your screen is captured, so the PC stays free for other things while the film plays, and only the film appears on the TV.
Side by side
| Aspect | Screen mirroring (Windows) | Casting with AIX Player |
|---|---|---|
| What reaches the TV | A live copy of everything on your screen | The video file’s own stream |
| Picture | Captured from the screen and compressed as it goes, at what the wireless link can carry | The original, when the TV can play it directly; otherwise converted while it streams |
| HDR | Whatever the desktop shows | Stays HDR when the TV can play the file directly; otherwise converted to SDR for the TV |
| Subtitles | Whatever the player on screen shows | The subtitle you choose shows on the TV |
| Sound | Sent along with the screen capture | The file’s own soundtrack, or AAC sound when the stream is converted |
| Your PC meanwhile | Shown on the TV, so it is tied to the picture | Free to use; the TV shows only the film |
| TVs it works with | TVs and adapters with wireless display (Miracast) support | Seven TV families: Google Cast, Fire TV, Roku, Apple TV, LG webOS, Samsung Tizen, DLNA |
| Best for | Slides, web pages, photos, anything on screen | Films and videos from your drives |
Screen mirroring is a Windows feature; how well it works depends on the PC, the TV or adapter and the network.
Why casting can start without converting the whole file
Televisions play a limited list of video and audio types. When a file contains something the TV cannot play, AIX Player converts that part as the video plays, frame by frame, instead of preparing a converted copy first. That is why the film can start straight away. Nothing is written to disk and the original file is untouched.
The conversion runs on your PC. On NVIDIA, AMD and Intel graphics the graphics card converts the video; on Snapdragon PCs only H.264 encoding is hardware-assisted, and other stages use the processor. Every converted stream carries AAC sound. When the TV can play the file directly, nothing is converted at all.
HDR and subtitles
HDR stays HDR when the TV can play the file directly; otherwise the picture is converted to SDR for the TV. With mirroring, the TV sees whatever your desktop shows.
With casting, the subtitle you choose in AIX Player shows on the TV, including a separate subtitle file you added. The subtitles when casting guide has the details.
Which one to use
- Mirror when you want the TV to show something other than a video file: a presentation, a website, a family photo album.
- Cast when you want to watch a film or a video from your PC’s drive or a USB or SD drive, with your soundtrack and subtitle, while the PC stays free.
- No TV in either list? Check which casting family your TV belongs to first: many smart TVs already do one of the two.
Casting from AIX Player is part of AIX Pro, with 60 free casting minutes in total, once, in the free app; screen mirroring is part of Windows. If a cast misbehaves, the casting troubleshooting guide takes the usual causes in order.
Cast the film, not the desktop.
Install AIX Player, open a video, press cast. That’s the whole setup.
GET IT FROM Microsoft StoreLocal playback is free. The free app includes 60 casting minutes in total—once, not per session—and Pro makes casting unlimited. See current pricing in the Microsoft Store.