---
title: Video, HDR, and shaders
description: Configure render backends, HDR pipelines, debanding, Anime4K, filters, and thermal-aware playback.
---

Start with automatic hardware decoding and the default renderer. Advanced processing can improve difficult content, but it also increases GPU load, heat, and battery use.

## Render backend

mpvRx can select between OpenGL and Vulkan paths and between mpv's `gpu` and `gpu-next` output behavior. Driver quality varies by device.

:::tip[Compatibility first]
If a video fails, stutters, or shows corruption, remove custom shaders and decoder overrides before switching the entire build variant.
:::

## HDR pipelines

The bundled hdr-toys collection provides 77 GLSL shaders and four high-level modes:

- BT.2100 PQ for HDR10-style sources
- BT.2100 HLG
- BT.2020 gamut mapping
- Linear HDR, including optional SDR-to-HDR boosting

Correct output depends on the source metadata, display capability, Android composition path, and renderer. Compare against the unmodified image before keeping a pipeline enabled globally.

## Anime4K

Seven presets are available: Off, A, B, C, A+, B+, and C+. Device-oriented quality choices provide Fast, Balanced, and High tiers. mpvRx can disable Anime4K for high-resolution content and lower its quality under thermal pressure.

Anime4K is most useful for compatible animated sources at lower resolutions. It is not a universal sharpness switch.

## Debanding and filters

- CPU debanding uses `gradfun`.
- GPU debanding exposes iterations, threshold, range, and grain.
- Video filter presets include Vivid, Cinematic, Dramatic, Ghibli Style, Neon Pop, and Deep Black.
- Ambient GLOW and FRAME_EXTEND modes render around the video with configurable blur, color, warmth, vignette, and noise controls.
- Automatic cropping can analyze supported videos for encoded black borders.

### Tune GPU debanding

| Control | Effect |
| --- | --- |
| Iterations | Repeats the debanding pass; higher values increase GPU cost. |
| Threshold | Controls how readily subtle gradients are treated as banding. |
| Range | Expands the neighborhood sampled around each pixel. |
| Grain | Adds controlled noise to mask remaining quantization steps. |

Begin with one iteration and conservative threshold/range. Too much processing
can erase intentional texture or add visible noise.

### Ambient modes

**GLOW** extends color and light beyond the picture, while **FRAME_EXTEND**
uses the frame itself as the surrounding composition. Settings include sample
count, blur, intensity, saturation, warmth, vignette, and dither/noise.

mpvRx caches compiled shader configurations and reduces the effective sample
budget under thermal pressure. Adjust one parameter at a time; sample count and
blur radius usually have the largest performance impact.

### Filter presets

Presets are creative starting points rather than calibration profiles. Preview
them on representative bright, dark, animated, and skin-tone scenes before
applying one broadly. Deep Black can crush shadow detail on an already dark
master; vivid or neon looks can clip saturated colors.

## Automatic crop

Auto Crop samples several frames and looks for persistent encoded borders. It
is conservative around dark scenes, short files, rotation, and changing aspect
ratios, then caches a successful result for repeat playback.

Disable it for intentional letterboxing, rapidly changing aspect ratios, or
content where edge darkness is part of the image. Crop, stretch, pan, zoom, and
ambient output share the final video geometry.

## Watch thermal behavior

The thermal monitor samples headroom during playback. Shader budgets and Anime4K choices can be reduced before sustained heat becomes dropped frames. Use [Statistics and refresh rate](/docs/playback/statistics-and-refresh-rate) to compare FPS, dropped frames, decoder state, temperature, and power draw after each change.