Defines transformations that could be performed on  ASImage .

Transformations can be performed with different degree of quality.
Internal engine uses 24.8 bits per channel per pixel. As the result
there are no precision loss, while performing complex calculations.
Error diffusion algorithms could be used to  transform  it back into 8
bit without quality loss.

Any Transformation could be performed with the result written directly
into XImage, so that it could be displayed faster.

Complex interpolation algorithms are used to perform scaling
operations, thus yielding very good quality. All the transformations
are performed in integer math, with the result of greater speeds.
Optional MMX inline assembly has been incorporated into some
procedures, and allows to achieve considerably better performance on
compatible CPUs.

 Transformations :
         scale_asimage(), tile_asimage(), merge_layers(), 
            make_gradient(), flip_asimage(), mirror_asimage(), 
            pad_asimage(), blur_asimage_gauss(), fill_asimage(), 
            adjust_asimage_hsv()

 Other  libAfterImage  modules :
          ascmap .h  asfont .h  asimage .h  asvisual .h  blender .h  export .h
          import .h  transform .h  ximage .h

Sasha Vasko <sasha at aftercode dot net>

- scales source  ASImage into new image of requested dimensions.

 ASImage  *scale_asimage( struct  ASVisual  *asv,
                         ASImage  *src,
                        unsigned int to_width,
                        unsigned int to_height,
                         ASAltImFormats  out_format,
                        unsigned int compression_out, int quality );

asv

- pointer to valid  ASVisual structure

src

- source  ASImage

to_width

- desired width of the resulting image

to_height

- desired height of the resulting image

out_format

- optionally describes alternative  ASImage format that should be produced as the result - XImage,  ARGB32 , etc.

compression_out-

compression level of resulting image in range 0-100.

quality

- output quality

returns newly created and encoded  ASImage  on success, NULL of failure.

If size has to be reduced - then several neighboring pixels will be 
averaged into single pixel. If size has to be increased then new 
pixels will be interpolated based on values of four neighboring pixels.

 ASScale 

- tiles/crops  ASImage to desired size, while optionaly tinting it at the same time.

 ASImage  *tile_asimage ( struct  ASVisual  *asv,
                         ASImage  *src,
                        int offset_x,
                        int offset_y,
                        unsigned int to_width,
                        unsigned int to_height,
                         ARGB32   tint ,
                         ASAltImFormats  out_format,
                        unsigned int compression_out, int quality );

asv

- pointer to valid  ASVisual structure

src

- source  ASImage

offset_x

- left clip margin

offset_y

- right clip margin

to_width

- desired width of the resulting image

to_height

- desired height of the resulting image

tint

-  ARGB32  value describing tinting  color .

out_format

- optionally describes alternative  ASImage format that should be produced as the result - XImage,  ARGB32 , etc.

compression_out-

compression level of resulting image in range 0-100.

quality

- output quality

returns newly created and encoded  ASImage  on success, NULL of failure.

Offset_x and offset_y define origin on source image from which
tiling will  start . If offset_x or offset_y is outside of the image
boundaries, then it will be reduced by whole number of image sizes to
fit inside the image. At the time of tiling image will be tinted
unless  tint  == 0.

 ASTile 

 ASImage  *merge_layers  ( struct  ASVisual  *asv,
                          ASImageLayer  *layers, int count,
                         unsigned int dst_width,
                         unsigned int dst_height,
                          ASAltImFormats  out_format,
                         unsigned int compression_out, int quality);

asv

- pointer to valid  ASVisual structure

layers

- array of  ASImageLayer structures that will be rendered one on top of another. First element corresponds to the bottommost layer.

dst_width

- desired width of the resulting image

dst_height

- desired height of the resulting image

out_format

- optionally describes alternative  ASImage format that should be produced as the result - XImage,  ARGB32 , etc.

compression_out

- compression level of resulting image in range 0-100.

quality

- output quality

returns newly created and encoded  ASImage  on success, NULL of failure.

merge_layers() will  create  new  ASImage  of requested size. It will then
go through all the layers, and  fill  image with composition.
Bottommost layer will be used unchanged and above layers will be
superimposed on it, using algorithm specified in  ASImageLayer 
structure of the overlaying layer. Layers may have smaller size
then destination image, and maybe placed in arbitrary locations. Each
layer will be padded to fit width of the destination image with all 0
effectively making it transparent.

- renders linear  gradient into new  ASImage

 ASImage  *make_gradient ( struct  ASVisual  *asv,
                         struct  ASGradient  *grad,
                         unsigned int width,
                         unsigned int height,
                         ASFlagType filter,
                          ASAltImFormats  out_format,
                         unsigned int compression_out, int quality);

asv

- pointer to valid  ASVisual structure

grad

-  ASGradient structure defining how  gradient should be drawn

width

- desired width of the resulting image

height

- desired height of the resulting image

filter

- only channels corresponding to  set bits will be rendered.

out_format

- optionally describes alternative  ASImage format that should be produced as the result - XImage,  ARGB32 , etc.

compression_out-

compression level of resulting image in range 0-100.

quality

- output quality

returns newly created and encoded  ASImage  on success, NULL of failure.

make_gradient() will  create  new image of requested size and it will
 fill  it with  gradient , described in structure pointed to by grad.
Different dithering techniques will be applied to produce nicer
looking gradients.

- rotates  ASImage in 90 degree increments

 ASImage  *flip_asimage ( struct  ASVisual  *asv,
                         ASImage  *src,
                        int offset_x, int offset_y,
                        unsigned int to_width,
                        unsigned int to_height,
                        int  flip ,  ASAltImFormats  out_format,
                        unsigned int compression_out, int quality );

asv

- pointer to valid  ASVisual structure

src

- source  ASImage

offset_x

- left clip margin

offset_y

- right clip margin

to_width

- desired width of the resulting image

to_height

- desired height of the resulting image

flip

-  flip flags determining degree of rotation.

out_format

- optionally describes alternative  ASImage format that should be produced as the result - XImage,  ARGB32 , etc.

compression_out

- compression level of resulting image in range 0-100.

quality

- output quality

returns newly created and encoded  ASImage  on success, NULL of failure.

flip_asimage() will  create  new image of requested size, it will then
 tile  source image based on offset_x, offset_y, and destination size,
and it will  rotate  it then based on  flip   value . Three rotation angles
supported 90, 180 and 270 degrees.

 ASImage  *mirror_asimage ( struct  ASVisual  *asv,
                           ASImage  *src,
                          int offset_x, int offset_y,
                          unsigned int to_width,
                          unsigned int to_height,
                          Bool vertical,  ASAltImFormats  out_format,
                          unsigned int compression_out, int quality );

asv

- pointer to valid  ASVisual structure

src

- source  ASImage

offset_x

- left clip margin

offset_y

- right clip margin

to_width

- desired width of the resulting image

to_height

- desired height of the resulting image

vertical

-  mirror in vertical direction.

out_format

- optionally describes alternative  ASImage format that should be produced as the result - XImage,  ARGB32 , etc.

compression_out

- compression level of resulting image in range 0-100.

quality

- output quality

returns newly created and encoded  ASImage  on success, NULL of failure.

mirror_asimage() will  create  new image of requested size, it will then
 tile  source image based on offset_x, offset_y, and destination size,
and it will  mirror  it in vertical or horizontal direction.

enlarges  ASImage , padding it with specified  color on each side in accordance with requested geometry.

 ASImage  *pad_asimage(  ASVisual  *asv,  ASImage  *src,
                     int dst_x, int dst_y,
                     unsigned int to_width,
                     unsigned int to_height,
                      ARGB32   color ,
                      ASAltImFormats  out_format,
                     unsigned int compression_out, int quality );

asv

- pointer to valid  ASVisual structure

src

- source  ASImage

dst_x,

dst_y - placement of the source image relative to the origin of destination image

to_width

- width of the destination image

to_height

- height of the destination image

color

-  ARGB32  color  value to  pad with.

out_format

- optionally describes alternative  ASImage format that should be produced as the result - XImage,  ARGB32 , etc.

compression_out

- compression level of resulting image in range 0-100.

quality

- output quality

returns newly created and encoded  ASImage  on success, NULL of failure.

Performs Gaussian blurr of the image ( usefull for drop shadows and the likes ).

 ASImage * blur_asimage_gauss(  ASVisual * asv,  ASImage * src,
                             double horz, double vert,
                              ASAltImFormats  out_format,
                             unsigned int compression_out, 
                                int quality );

asv

- pointer to valid  ASVisual structure

src

- source  ASImage

horz

- horizontal radius of the blurr

vert

- vertical radius of the blurr

out_format

- optionally describes alternative  ASImage format that should be produced as the result - XImage,  ARGB32 , etc.

compression_out

- compression level of resulting image in range 0-100.

quality

- output quality

returns newly created and encoded  ASImage  on success, NULL of failure.

- Fills rectangle within the existing  ASImage with specified  color .

Bool fill_asimage(  ASVisual  *asv,  ASImage  *im,
                   int x, int y, int width, int height,
                    ARGB32   color  );

asv

- pointer to valid  ASVisual structure

im

-  ASImage to  fill with the  color

x,

y - left-top corner of the rectangle to  fill .

width,

height - size of the rectangle to  fill .

color

-  ARGB32  color  value to  fill rectangle with.

True on success, False on failure.

- adjusts image  color properties in HSV  colorspace

 ASImage  *adjust_asimage_hsv(  ASVisual  *asv,  ASImage  *src,
                             int offset_x, int offset_y,
                             unsigned int to_width,
                             unsigned int to_height,
                             unsigned int affected_hue,
                             unsigned int affected_radius,
                             int hue_offset, int saturation_offset,
                             int value_offset,
                              ASAltImFormats  out_format,
                             unsigned int compression_out, int quality);

asv

- pointer to valid  ASVisual structure

src

-  ASImage to  adjust colors of.

offset_x,

offset_y

- position on infinite surface tiled with original image, of the left-top corner of the area to be used for new image.

to_width,

to_height

- size of the area of the original image to be used for new image.

affected_hue

-  hue in degrees in range 0-360. This allows to limit impact of  color adjustment to affect only limited range of hues.

affected_radius

Sets the diapason of the range of affected hues.

hue_offset

-  value by which to change hues in affected range.

saturation_offset

-  value by which to change saturation of the pixels in affected  hue range.

value_offset

-  value by which to change Value(brightness) of pixels in affected  hue range.

out_format

- optionally describes alternative  ASImage format that should be produced as the result - XImage,  ARGB32 , etc.

compression_out-

compression level of resulting image in range 0-100.

quality

- output quality

returns newly created and encoded  ASImage  on success, NULL of failure.

This function will  tile  original image to specified size with offsets
requested, and then it will go though it and  adjust   hue , saturation and
 value  of those pixels that have specific  hue ,  set  by affected_hue/
affected_radius parameters. When affected_radius is greater then 180
entire image will be adjusted. Note that since grayscale colors have
no  hue  - the will not  get  adjusted. Only saturation and  value  will be
adjusted in gray pixels.
Hue is measured as an angle on a 360 degree circle, The following is
relationship of  hue  values to regular  color  names :
red      - 0
yellow   - 60
green    - 120
cyan     - 180
blue     - 240
magenta  - 300
red      - 360

All the  hue  values in parameters will be adjusted to fall withing
0-360 range.

creates  ASImage from double precision indexed image data - usefull for scientific visualisation.

Bool colorize_asimage_vector(  ASVisual  *asv,  ASImage  *im,
                                  ASVectorPalette  *palette,
                               ASAltImFormats  out_format,
                              int quality );

asv

- pointer to valid  ASVisual structure

im

-  ASImage to update.

palette

- palette to be used in conversion of double precision values into colors.

out_format

- optionally describes alternative  ASImage format that should be produced as the result - XImage,  ARGB32 , etc.

quality

- output quality

True on success, False on failure.

This function will try to convert double precision indexed image data
into actuall  color  image using palette. Original data should be 
attached to  ASImage  using vector member. Operation is relatively fast 
and allows representation of scientific data as  color  image with 
dynamically changing palette.

- convinience function allowing to  create new  ASImage ,  set its vector data and  colorize it using palette - all in one step.

 ASImage  *create_asimage_from_vector(  ASVisual  *asv, double *vector,
                                     unsigned int width,
                                     unsigned int height,
                                      ASVectorPalette  *palette,
                                      ASAltImFormats  out_format,
                                     unsigned int compression,
                                     int quality );

asv

- pointer to valid  ASVisual structure

vector

- data to be attached to new  ASImage and used to generate RGB image

width,

height - size of the new image.

palette

- palette to be used in conversion of double precision values into colors.

out_format

- optionally describes alternative  ASImage format that should be produced as the result - XImage,  ARGB32 , etc.

compression_out-

compression level of resulting image in range 0-100.

quality

- output quality

New  ASImage   on success, NULL on failure.

colorize_asimage_vector(), create_asimage(), set_asimage_vector()

-  slice  ASImage leaving its corners intact, and scaling the middle part.

 ASImage *
slice_asimage2(  ASVisual  *asv,  ASImage  *src,
            int slice_x_start, int slice_x_end,
            int slice_y_start, int slice_y_end,
            int to_width,
            int to_height,
            Bool scaled,
             ASAltImFormats  out_format,
            unsigned int compression_out, int quality );

asv

- pointer to valid  ASVisual structure

src

- source  ASImage .

slice_x_start

- ending of the left corners

slice_x_end

- begining of the right corners

slice_y_start

- ending of the top corners

slice_y_end

- begining of the bottom corners

to_width

- width of the generated image;

to_height

- height of the generated image;

scaled

-  if True - middle part of the image will be scaled, otherwise - tiled;

out_format

- optionally describes alternative  ASImage format that should be produced as the result - XImage,  ARGB32 , etc.;

compression_out-

compression level of resulting image in range 0-100;

quality

- output quality.

New  ASImage   on success, NULL on failure.

scale_asimage(), tile_asimage()