---
title: "GifFrame..::.ColorKeyIndex Property "
canonical: https://www.graphicsmill.com/docs/gm5/P_Aurigma_GraphicsMill_Codecs_GifFrame_ColorKeyIndex.htm
product: "Graphics Mill 5.5 for .NET"
---

This documentation is for the old version. [Go to the latest Graphics Mill docs](https://www.graphicsmill.com/docs/gm/)

# GifFrame.ColorKeyIndex Property 
 
Returns an index of transparent palette entry.
 
**Namespace:** [Aurigma.GraphicsMill.Codecs](https://www.graphicsmill.com/docs/gm5/N_Aurigma_GraphicsMill_Codecs.htm.md)
 **Assembly:** Aurigma.GraphicsMill (in Aurigma.GraphicsMill.dll)
 
## Syntax
  
```
Public ReadOnly Property ColorKeyIndex As Integer
```
 
```csharp
public int ColorKeyIndex { get; }
```
 
### Property Value
Index of the transparent palette entry. If the frame has no transparent areas, -1 is returned.
 
## Remarks
  
This value is read from GIF file rather than obtained from the bitmap. It means that if you modify the bitmap with [SetBitmap(Bitmap)](https://www.graphicsmill.com/docs/gm5/M_Aurigma_GraphicsMill_Codecs_Frame_SetBitmap_1_fd4033ef.htm.md) method, it will still return the value stored in the file this frame is associated with. Therefore this property has limited usage.
 
This property is not used when you pass this frame into [GifWriter](https://www.graphicsmill.com/docs/gm5/T_Aurigma_GraphicsMill_Codecs_GifWriter.htm.md). Instead of that writer analyzes the palette of the image stored in this frame and initalizes this value in the result GIF file with it.
   
## See Also

### Reference

- [GifFrame Class](https://www.graphicsmill.com/docs/gm5/T_Aurigma_GraphicsMill_Codecs_GifFrame.htm.md)
- [Aurigma.GraphicsMill.Codecs Namespace](https://www.graphicsmill.com/docs/gm5/N_Aurigma_GraphicsMill_Codecs.htm.md)