What the picture tells you
| What you see | Likely cause |
|---|---|
| Blocky squares in fast motion, on one channel only | That channel is sent at a low bitrate |
| Soft picture that sharpens after a while, or comes and goes | Adaptive streaming dropping to a lower version when your connection slows |
| Soft on every channel, all the time | A low-resolution stream, a player setting, or the TV upscaling |
| Smeared or “soap opera” motion | The TV’s motion smoothing |
| Judder in pans, every few seconds | Frame rate mismatch; see IPTV lagging |
How much data a good picture needs
The quality of a stream depends mostly on its bitrate, the amount of data per second. Apple’s HLS authoring specification gives one example set of bitrates for streaming to its devices:
| Resolution | H.264 | H.265 (HEVC) |
|---|---|---|
| 720p | 3 to 4.5 Mbps | 2.4 to 3.4 Mbps |
| 1080p | 6 to 7.8 Mbps | 4.5 to 5.8 Mbps |
| 4K (2160p) | – | 11.6 to 16.8 Mbps |
These are Apple’s starting points, not rules for every provider, but they show the scale: a 1080p stream squeezed far below these figures loses detail in fast motion first, which is why sport shows it most.
Fix the stream and the connection
- Compare channels. If one channel is blocky and others are sharp, the channel itself is the limit. Try its HD or 4K version if there is one.
- Check whether quality changes over time. Adaptive streams offer several versions at different bitrates, and the player switches between them as your connection changes. A picture that softens in the evening points to a busy connection. See how to stop IPTV buffering and internet speed for IPTV.
- Use a cable or 5 GHz Wi-Fi. A steadier connection lets the player stay on the top version. See Wi-Fi vs Ethernet.
- Pick a quality, if the player offers it. Some players let you choose a fixed quality instead of automatic. Choosing the top one helps if your connection is fast but the player is cautious; if it then buffers, go back to automatic.
Fix the player and the device
- Switch the player engine or decoder. A different engine can handle a stream better. See playback error for where to find the setting.
- Set the device’s output correctly. Leave the video resolution on automatic so the device sends the TV’s native resolution, and turn on frame rate matching where the device has it.
- Check the device can handle the stream. An old stick may struggle with 4K or H.265 channels. See codec not supported.
Fix the TV’s picture settings
- Turn off motion smoothing (it has a different name on each brand) if movement looks smeared or unnaturally smooth.
- Use a standard or film picture mode instead of a “vivid” or showroom mode, which exaggerates blockiness in dark scenes.
- Turn down sharpness. High sharpness adds halos and makes compression blocks stand out.
A 720p channel on a large 4K TV always looks softer than true 4K: the TV has to stretch it to nine times as many pixels. That’s upscaling, not a fault. See IPTV resolutions explained.