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# kVTCompressionPropertyKey_ConstantQualityFactor

```
let kVTCompressionPropertyKey_ConstantQualityFactor: CFString
```

## Discussion

\abstract Requires the encoder to maintain consistent quality by specifying a target constant quality factor in the range of 0.0 to 1.0.
\discussion In contrast to cases where kVTCompressionPropertyKey_Quality will cause the quantization parameter to adhere to a fixed value, this property is designed for consistent visual quality with or without bitrate limit constraints.
0.0 is the lowest quality and 1.0 implies the highest quality possible.

---

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