pixel_iterator
Pixel iterator pattern support functions
Contents
InitializePixelIteratorOptions
Synopsis
void InitializePixelIteratorOptions( PixelIteratorOptions *options,
ExceptionInfo *exception );
Description
InitializePixelIteratorOptions() assigns default options to a user-provided PixelIteratorOptions structure. This function should always be used to initialize the PixelIteratorOptions structure prior to making any changes to it.
The format of the InitializePixelIteratorOptions method is:
void InitializePixelIteratorOptions( PixelIteratorOptions *options,
ExceptionInfo *exception );
- options:
pointer to PixelIteratorOptions structure to initialize.
- exception:
Return any errors or warnings in this structure.
PixelIterateMonoRead
Synopsis
MagickPassFail PixelIterateMonoRead( PixelIteratorMonoReadCallback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data, const long x, const long y,
const unsigned long columns, const unsigned long rows,
const Image *image, ExceptionInfo *exception );
Description
PixelIterateMonoRead() iterates through a region of an image and invokes a user-provided callback function (of type PixelRowIteratorMonoReadCallback) for a row of pixels. This is useful to support simple operations such as statistics computation.
The format of the PixelIterateMonoRead method is:
MagickPassFail PixelIterateMonoRead( PixelIteratorMonoReadCallback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data, const long x, const long y,
const unsigned long columns, const unsigned long rows,
const Image *image, ExceptionInfo *exception );
- call_back:
A user-provided C callback function which is passed the address of pixels from the image.
- options:
Pixel iterator execution options (may be NULL).
- description:
textual description of operation being performed.
- mutable_data:
User-provided mutable context data.
- immutable_data:
User-provided immutable context data.
- x:
The horizontal ordinate of the top left corner of the region.
- y:
The vertical ordinate of the top left corner of the region.
- columns:
Width of pixel region
- rows:
Height of pixel region
- image:
The address of the Image.
- exception:
If an error is reported, this argument is updated with the reason.
PixelIterateMonoSet
Synopsis
MagickPassFail PixelIterateMonoSet( PixelIteratorMonoModifyback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data, const long x, const long y,
const unsigned long columns, const unsigned long rows,
Image *image, ExceptionInfo *exception );
Description
PixelIterateMonoSet() iterates through a region of an image and invokes a user-provided callback function (of type PixelIteratorMonoModifyCallback) to initialize a region of pixels from scratch. The difference from PixelIterateMonoModify() is that the output pixels are not initialized from the underlying store so it is more efficient when outputting a new image or when the existing pixels are intentionally discarded. This is useful for operations such as setting the pixel color.
The format of the PixelIterateMonoSet method is:
MagickPassFail PixelIterateMonoSet( PixelIteratorMonoModifyback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data, const long x, const long y,
const unsigned long columns, const unsigned long rows,
Image *image, ExceptionInfo *exception );
- call_back:
A user-provided C callback function which is passed the address of pixels to be initialized in the image.
- options:
Pixel iterator execution options (may be NULL).
- description:
textual description of operation being performed.
- mutable_data:
User-provided mutable context data.
- immutable_data:
User-provided immutable context data.
- x:
The horizontal ordinate of the top left corner of the region.
- y:
The vertical ordinate of the top left corner of the region.
- columns:
Width of pixel region
- rows:
Height of pixel region
- image:
The address of the Image.
- exception:
If an error is reported, this argument is updated with the reason.
PixelIterateMonoModify
Synopsis
MagickPassFail PixelIterateMonoModify( PixelIteratorMonoModifyCallback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data, const long x,
const long y, const unsigned long columns,
const unsigned long rows, Image *image,
ExceptionInfo *exception );
Description
PixelIterateMonoModify() iterates through a region of an image and invokes a user-provided callback function (of type PixelIteratorMonoModifyCallback) to modify a region of pixels. This is useful to support simple operations such as level shifting, colorspace translation, or thresholding.
The format of the PixelIterateMonoModify method is:
MagickPassFail PixelIterateMonoModify( PixelIteratorMonoModifyCallback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data, const long x,
const long y, const unsigned long columns,
const unsigned long rows, Image *image,
ExceptionInfo *exception );
- call_back:
A user-provided C callback function which is passed the address of pixels from the image.
- options:
Pixel iterator execution options (may be NULL).
- description:
textual description of operation being performed.
- mutable_data:
User-provided mutable context data.
- immutable_data:
User-provided immutable context data.
- x:
The horizontal ordinate of the top left corner of the region.
- y:
The vertical ordinate of the top left corner of the region.
- columns:
Width of pixel region
- rows:
Height of pixel region
- image:
The address of the Image.
- exception:
If an error is reported, this argument is updated with the reason.
PixelIterateDualRead
Synopsis
MagickPassFail PixelIterateDualRead( PixelIteratorDualReadCallback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data, const unsigned long columns,
const unsigned long rows, const Image *first_image,
const long first_x, const long first_y,
const Image *second_image, const long second_x,
const long second_y, ExceptionInfo *exception ); ;
Description
PixelIterateDualRead() iterates through pixel regions of two images and invokes a user-provided callback function (of type PixelIteratorDualReadCallback) for each row of pixels. This is useful to support operations such as image comparison.
The format of the PixelIterateDualRead method is:
MagickPassFail PixelIterateDualRead( PixelIteratorDualReadCallback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data, const unsigned long columns,
const unsigned long rows, const Image *first_image,
const long first_x, const long first_y,
const Image *second_image, const long second_x,
const long second_y, ExceptionInfo *exception ); ;
- call_back:
A user-provided C callback function which is passed the address of pixels from each image.
- options:
Pixel iterator execution options (may be NULL).
- description:
textual description of operation being performed.
- mutable_data:
User-provided mutable context data.
- immutable_data:
User-provided immutable context data.
- columns:
Width of pixel region
- rows:
Height of pixel region
- first_image:
The address of the first Image.
- first_x:
The horizontal ordinate of the top left corner of the first region.
- first_y:
The vertical ordinate of the top left corner of the first region.
- second_image:
The address of the second Image.
- second_x:
The horizontal ordinate of the top left corner of the second region.
- second_y:
The vertical ordinate of the top left corner of the second region.
- exception:
If an error is reported, this argument is updated with the reason.
PixelIterateDualModify
Synopsis
MagickPassFail PixelIterateDualModify( PixelIteratorDualModifyCallback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data,
const unsigned long columns, const unsigned long rows,
const Image *source_image, const long source_x,
const long source_y, Image *update_image,
const long update_x, const long update_y,
ExceptionInfo *exception );
Description
PixelIterateDualModify() iterates through pixel regions of two images and invokes a user-provided callback function (of type PixelIteratorDualModifyCallback) for each row of pixels. This is useful to support operations such as composition.
The format of the PixelIterateDualModify method is:
MagickPassFail PixelIterateDualModify( PixelIteratorDualModifyCallback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data,
const unsigned long columns, const unsigned long rows,
const Image *source_image, const long source_x,
const long source_y, Image *update_image,
const long update_x, const long update_y,
ExceptionInfo *exception );
- call_back:
A user-provided C callback function which reads from a region of source pixels and updates a region of destination pixels.
- options:
Pixel iterator execution options (may be NULL).
- description:
textual description of operation being performed.
- mutable_data:
User-provided mutable context data.
- immutable_data:
User-provided immutable context data.
- columns:
Width of pixel region
- rows:
Height of pixel region
- source_image:
The address of the constant source Image.
- source_x:
The horizontal ordinate of the top left corner of the source region.
- source_y:
The vertical ordinate of the top left corner of the source region.
- update_image:
The address of the update Image.
- update_x:
The horizontal ordinate of the top left corner of the update region.
- update_y:
The vertical ordinate of the top left corner of the update region.
- exception:
If an error is reported, this argument is updated with the reason.
PixelIterateDualNew
Synopsis
MagickPassFail PixelIterateDualNew( PixelIteratorDualNewCallback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data, const unsigned long columns,
const unsigned long rows, const Image *source_image,
const long source_x, const long source_y,
Image *new_image, const long new_x,
const long new_y, ExceptionInfo *exception );
Description
PixelIterateDualNew() iterates through pixel regions of two images and invokes a user-provided callback function (of type PixelIteratorDualNewCallback) for each row of pixels. This is used if a new output image is created based on an input image. The difference from PixelIterateDualModify() is that the output pixels are not initialized so it is more efficient when outputting a new image.
The format of the PixelIterateDualNew method is:
MagickPassFail PixelIterateDualNew( PixelIteratorDualNewCallback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data, const unsigned long columns,
const unsigned long rows, const Image *source_image,
const long source_x, const long source_y,
Image *new_image, const long new_x,
const long new_y, ExceptionInfo *exception );
- call_back:
A user-provided C callback function which reads from a region of source pixels and initializes a region of destination pixels.
- options:
Pixel iterator execution options (may be NULL).
- description:
textual description of operation being performed.
- mutable_data:
User-provided mutable context data.
- immutable_data:
User-provided immutable context data.
- columns:
Width of pixel region
- rows:
Height of pixel region
- source_image:
The address of the constant source Image.
- source_x:
The horizontal ordinate of the top left corner of the source region.
- source_y:
The vertical ordinate of the top left corner of the source region.
- new_image:
The address of the new Image.
- new_x:
The horizontal ordinate of the top left corner of the new region.
- new_y:
The vertical ordinate of the top left corner of the new region.
- exception:
If an error is reported, this argument is updated with the reason.
PixelIterateTripleModify
Synopsis
MagickPassFail PixelIterateTripleModify( PixelIteratorTripleModifyCallback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data,
const unsigned long columns, const unsigned long rows,
const Image *source1_image,
const Image *source2_image, const long source_x,
const long source_y, Image *update_image,
const long update_x, const long update_y,
ExceptionInfo *exception );
Description
PixelIterateTripleModify() iterates through pixel regions of three images and invokes a user-provided callback function (of type PixelIteratorTripleModifyCallback) for each row of pixels. The first two images are read-only, while the third image is read-write for update. Access of the first two images is done lock-step using the same coordinates. This is useful to support operations such as image differencing.
The format of the PixelIterateTripleModify method is:
MagickPassFail PixelIterateTripleModify( PixelIteratorTripleModifyCallback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data,
const unsigned long columns, const unsigned long rows,
const Image *source1_image,
const Image *source2_image, const long source_x,
const long source_y, Image *update_image,
const long update_x, const long update_y,
ExceptionInfo *exception );
- call_back:
A user-provided C callback function which reads from a region of source pixels and updates a region of destination pixels.
- options:
Pixel iterator execution options (may be NULL).
- description:
textual description of operation being performed.
- mutable_data:
User-provided mutable context data.
- immutable_data:
User-provided immutable context data.
- columns:
Width of pixel region
- rows:
Height of pixel region
- source1_image:
The address of the constant source 1 Image.
- source2_image:
The address of the constant source 2 Image.
- source_x:
The horizontal ordinate of the top left corner of the source regions.
- source_y:
The vertical ordinate of the top left corner of the source regions.
- update_image:
The address of the update Image.
- update_x:
The horizontal ordinate of the top left corner of the update region.
- update_y:
The vertical ordinate of the top left corner of the update region.
- exception:
If an error is reported, this argument is updated with the reason.
PixelIterateTripleNew
Synopsis
MagickPassFail PixelIterateTripleNew( PixelIteratorTripleNewCallback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data,
const unsigned long columns, const unsigned long rows,
const Image *source1_image,
const Image *source2_image, const long source_x,
const long source_y, Image *new_image,
const long new_x, const long new_y,
ExceptionInfo *exception );
Description
PixelIterateTripleNew() iterates through pixel regions of three images and invokes a user-provided callback function (of type PixelIteratorTripleNewCallback) for each row of pixels. The first two images are read-only, while the third image is read-write for update. Access of the first two images is done lock-step using the same coordinates. This is used if a new output image is created based on two input images. The difference from PixelIterateTripleModify() is that the output pixels are not initialized so it is more efficient when outputting a new image.
The format of the PixelIterateTripleNew method is:
MagickPassFail PixelIterateTripleNew( PixelIteratorTripleNewCallback call_back,
const PixelIteratorOptions *options,
const char *description, void *mutable_data,
const void *immutable_data,
const unsigned long columns, const unsigned long rows,
const Image *source1_image,
const Image *source2_image, const long source_x,
const long source_y, Image *new_image,
const long new_x, const long new_y,
ExceptionInfo *exception );
- call_back:
A user-provided C callback function which reads from a region of source pixels and initializes a region of destination pixels.
- options:
Pixel iterator execution options (may be NULL).
- description:
textual description of operation being performed.
- mutable_data:
User-provided mutable context data.
- immutable_data:
User-provided immutable context data.
- columns:
Width of pixel region
- rows:
Height of pixel region
- source1_image:
The address of the constant source 1 Image.
- source2_image:
The address of the constant source 2 Image.
- source_x:
The horizontal ordinate of the top left corner of the source regions.
- source_y:
The vertical ordinate of the top left corner of the source regions.
- new_image:
The address of the new Image.
- new_x:
The horizontal ordinate of the top left corner of the new region.
- new_y:
The vertical ordinate of the top left corner of the new region.
- exception:
If an error is reported, this argument is updated with the reason.