# GH_MemoryBitmap class

Namespace: [Grasshopper.Kernel](https://developer.rhino3d.com/api/gh1/namespace/grasshopper.kernel.md) · Assembly: [Grasshopper](https://developer.rhino3d.com/api/gh1/assembly/grasshopper.md)

```cs
public sealed class GH_MemoryBitmap
```

Utility class for ultra-fast bitmap sampling and filters.

## Constructors

- [GH_MemoryBitmap](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/ctor.md): (2 overloads) Constructor with Wrap mode override.

## Properties

- [HasAlphaChannel](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/hasalphachannel.md): Gets a value indicating whether or not the local image has an alpha channel defined.
- [Height](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/height.md): Gets the height (in pixels) of the local image.
- [SizeOf](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/sizeof.md): Gets the size (in bytes) of the local image.
- [Width](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/width.md): Gets the width (in pixels) of the local image.

## Methods

- [A](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/a.md): Gets the alpha channel value at the given pixel coordinates.
- [B](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/b.md): Gets the blue channel value at the given pixel coordinates.
- [Colour](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/colour.md): (2 overloads) Gets the colour at the given pixel coordinates.
- [CopyChannel](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/copychannel.md): Copy the contents of one channel into another.
- [Filter_AlphaEdges](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-alphaedges.md): Set the alpha component on all edges to a specific value.
- [Filter_Blur](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-blur.md): (4 overloads) Blur the image in both directions.
- [Filter_BlurAlpha](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-bluralpha.md): Blur the alpha channel of the image N times in both directions.
- [Filter_Contrast](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-contrast.md): Adjust the contrast of a specific channel.
- [Filter_DitherPattern](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-ditherpattern.md): Create a checkerboard dither pattern.
- [Filter_DropShadow](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-dropshadow.md): Add a drop-shadow to the image. Image is not grown, so if you want the drop shadow to extend beyond the image boundaries, you have to add padding to the image first.
- [Filter_Dullify](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-dullify.md): Reduces contrast based on opacity. This filter pulls all colours towards dull grey, without wrecking drop-shadows.
- [Filter_Equalize](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-equalize.md): Set all the values in a specific channel to a specific value.
- [Filter_GreyScale](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-greyscale.md): (2 overloads) Convert the image to a greyscale shadow of its former self.
- [Filter_HueScale](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-huescale.md): Convert the image to a greyscale representation of the hues.
- [Filter_Invert](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-invert.md): Invert all values in a specific channel.
- [Filter_LumScale](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-lumscale.md): Convert the image to a greyscale representation of the luminance.
- [Filter_Multiply](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-multiply.md): (2 overloads) Multiply all values in a specific channel with a specific factor, using a custom scaling center anchor.
- [Filter_SatScale](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-satscale.md): Convert the image to a greyscale representation of the saturation.
- [Filter_Shift](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-shift.md): Shift all values in a specific channel with a specific amount.
- [Filter_SpectrumScale](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-spectrumscale.md): Convert the image to a spectral representation of the hues.
- [Filter_Tint](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/filter-tint.md): Colorize the image using Hue and Saturation from a base colour.
- [Finalize](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/finalize.md)
- [G](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/g.md): Gets the greeb channel value at the given pixel coordinates.
- [OpaqueArea](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/opaquearea.md): Find the opaque area of a bitmap. The opaque area is the rectangle that contains pixels with a colour that is not fully transparent.
- [PadBitmap](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/padbitmap.md): (static) Add padding edges around a bitmap.
- [R](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/r.md): Gets the red channel value at the given pixel coordinates.
- [Release](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/release.md): Release the locked bits. You must call this function when you are done with this GH_MemoryBitmap instance.
- [Sample](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/sample.md): (2 overloads) Top level sampling function for interpolated sampling.
- [ShrinkBitmap](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-memorybitmap/shrinkbitmap.md): (static) Shrink an image by removing all outer columns and rows that contain only fully transparent pixels.