NAME

zoom - Methods to Resize an Image


SYNOPSIS

Image * MagnifyImage( image, ExceptionInfo *exception );

Image * MinifyImage( Image *image, ExceptionInfo *exception );

Image * ResizeImage( Image *image, const unsigned int columns, const unsigned int rows, const FilterType filter, const double blur, ExceptionInfo *exception );

Image * SampleImage( Image *image, const unsigned int columns, const unsigned int rows, ExceptionInfo *exception );

Image * ScaleImage( Image *image, const unsigned int columns, const unsigned int rows, ExceptionInfo *exception );


FUNCTION DESCRIPTIONS

MagnifyImage

MagnifyImage is a convenience method that scales an image proportionally to twice its size. If a NULL image is returned, check the exception member of image to determine why the image failed to magnify.

The format of the MagnifyImage method is:

Image *MagnifyImage ( image, ExceptionInfo *exception );

A description of each parameter follows:

image:
The image.

exception:
Return any errors or warnings in this structure.

MinifyImage

MinifyImage is a convenience method that scales an image proportionally to half its size. If a NULL image is returned, check the exception member of image to determine why the image failed to minify.

The format of the MinifyImage method is:

Image *MinifyImage ( Image *image, ExceptionInfo *exception );

A description of each parameter follows:

image:
The image.

exception:
Return any errors or warnings in this structure.

ResizeImage

ResizeImage scales an image to the desired dimensions with one of these filters:

  Bessel   Blackman   Box
  Catrom   Cubic      Gaussian
  Hanning  Hermite    Lanczos
  Mitchell Point      Quandratic
  Sinc     Triangle

If a NULL image is returned, check exception to determine why the image failed to scale.

The format of the ResizeImage method is:

Image *ResizeImage ( Image *image, const unsigned int columns, const unsigned int rows, const FilterType filter, const double blur, ExceptionInfo *exception );

A description of each parameter follows:

image:
The image.

columns:
The number of columns in the scaled image.

rows:
The number of rows in the scaled image.

filter:
Image filter to use.

blur:
The blur factor where > 1 is blurry, < 1 is sharp.

exception:
Return any errors or warnings in this structure.

SampleImage

SampleImage scales an image to the desired dimensions with pixel sampling. Unlike other scaling methods, this method does not introduce any additional color into the scaled image. If a NULL image is returned, check exception to determine why the image failed to scale.

The format of the SampleImage method is:

Image *SampleImage ( Image *image, const unsigned int columns, const unsigned int rows, ExceptionInfo *exception );

A description of each parameter follows:

image:
The image.

columns:
The number of columns in the sampled image.

rows:
The number of rows in the sampled image.

exception:
Return any errors or warnings in this structure.

ScaleImage

ScaleImage changes the size of an image to the given dimensions. If a NULL image is returned, check exception to determine why the image failed to scale.

The format of the ScaleImage method is:

Image *ScaleImage ( Image *image, const unsigned int columns, const unsigned int rows, ExceptionInfo *exception );

A description of each parameter follows:

image:
The image.

columns:
The number of columns in the scaled image.

rows:
The number of rows in the scaled image.

exception:
Return any errors or warnings in this structure.