---
title: histogramForAlpha
framework: metalperformanceshaders
role: symbol
role_heading: Instance Property
path: metalperformanceshaders/mpsimagehistograminfo/histogramforalpha
---

# histogramForAlpha

Specifies whether the histogram for the alpha channel should be computed or not.

## Declaration

```swift
var histogramForAlpha: ObjCBool
```

## See Also

### Fields

- [numberOfHistogramEntries](metalperformanceshaders/mpsimagehistograminfo/numberofhistogramentries.md)
- [minPixelValue](metalperformanceshaders/mpsimagehistograminfo/minpixelvalue.md)
- [maxPixelValue](metalperformanceshaders/mpsimagehistograminfo/maxpixelvalue.md)