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# kVTCompressionPropertyKey_TargetQualityForAlpha

The target quality to use for encoding the alpha channel.

```
let kVTCompressionPropertyKey_TargetQualityForAlpha: CFString
```

## Discussion

Specify this value as a number in the range of `0.0` for the lowest quality to `1.0` for nearly lossless quality. Alpha plane bit rates tend to increase with increasing values. When encoding the alpha channel, the system gives priority to quality over bitrate.

> Important:
> Only HEVC with Alpha encoders support this parameter.

---

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