ChannelFxImage • CombineImages • GetImageAlphaChannel • SeparateImage • SeparateImages • SetImageAlphaChannel
ChannelFxImage
ChannelFxImage() applies a channel expression to the specified image. The expression consists of one or more channels, either mnemonic or numeric (e.g. red, 1), separated by actions as follows:
-channel-fx "red; green; blue"
A channel without an operation symbol implies separate (i.e, semicolon).
Image *ChannelFxImage(const Image *image,const char *expression, ExceptionInfo *exception)
A description of each parameter follows:
- image
- the image.
- expression
- A channel expression.
- exception
- return any errors or warnings in this structure.
CombineImages
CombineImages() combines one or more images into a single image. The grayscale value of the pixels of each image in the sequence is assigned in order to the specified channels of the combined image. The typical ordering would be image 1 => Red, 2 => Green, 3 => Blue, etc.
The format of the CombineImages method is:
Image *CombineImages(const Image *images,const ColorspaceType colorspace, ExceptionInfo *exception)
A description of each parameter follows:
- images
- the image sequence.
- colorspace
- the image colorspace.
- exception
- return any errors or warnings in this structure.
GetImageAlphaChannel
GetImageAlphaChannel() returns MagickFalse if the image alpha channel is not activated. That is, the image is RGB rather than RGBA or CMYK rather than CMYKA.
The format of the GetImageAlphaChannel method is:
MagickBooleanType GetImageAlphaChannel(const Image *image)
A description of each parameter follows:
- image
- the image.
SeparateImage
SeparateImage() separates a channel from the image and returns it as a grayscale image.
The format of the SeparateImage method is:
Image *SeparateImage(const Image *image,const ChannelType channel, ExceptionInfo *exception)
A description of each parameter follows:
- image
- the image.
- channel
- the image channel.
- exception
- return any errors or warnings in this structure.
SeparateImages
SeparateImages() returns a separate grayscale image for each channel specified.
The format of the SeparateImages method is:
Image *SeparateImages(const Image *image,ExceptionInfo *exception)
A description of each parameter follows:
- image
- the image.
- exception
- return any errors or warnings in this structure.
SetImageAlphaChannel
SetImageAlphaChannel() activates, deactivates, resets, or sets the alpha channel.
The format of the SetImageAlphaChannel method is:
MagickBooleanType SetImageAlphaChannel(Image *image, const AlphaChannelOption alpha_type,ExceptionInfo *exception)
A description of each parameter follows:
- image
- the image.
- alpha_type
- The alpha channel type: ActivateAlphaChannel, AssociateAlphaChannel, CopyAlphaChannel, DeactivateAlphaChannel, DisassociateAlphaChannel, ExtractAlphaChannel, OffAlphaChannel, OnAlphaChannel, OpaqueAlphaChannel, SetAlphaChannel, ShapeAlphaChannel, and TransparentAlphaChannel.
- exception
- return any errors or warnings in this structure.