transform.3x

Langue: en

Version: AfterStep v.2.2.9 (ubuntu - 24/10/10)

Section: 3 (Bibliothèques de fonctions)

NAME

transform - transformations available for ASImages libAfterImage/transform.h

NAMEtransform

SYNOPSIS

 Defines transformations that could be performed on ASImage.
 

DESCRIPTION

 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.
 

SEE ALSO

  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
 

AUTHOR

 Sasha Vasko <sasha at aftercode dot net>
 
libAfterImage/transform/scale_asimage()

NAMEscale_asimage()

- scales source ASImage into new image of requested dimensions.

SYNOPSIS

 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 );
 

INPUTS

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

RETURN VALUE

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

DESCRIPTION

 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.
 

EXAMPLE

 ASScale
 
libAfterImage/transform/tile_asimage()

NAMEtile_asimage()

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

SYNOPSIS

 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 );
 

INPUTS

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

RETURN VALUE

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

DESCRIPTION

 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.
 

EXAMPLE

 ASTile
 
libAfterImage/transform/merge_layers()

NAMEmerge_layers()

SYNOPSIS

 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);
 

INPUTS

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

RETURN VALUE

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

DESCRIPTION

 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.
 
libAfterImage/transform/make_gradient()

NAMEmake_gradient()

- renders linear gradient into new ASImage

SYNOPSIS

 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);
 

INPUTS

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

RETURN VALUE

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

DESCRIPTION

 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.
 
libAfterImage/transform/flip_asimage()

NAMEflip_asimage()

- rotates ASImage in 90 degree increments

SYNOPSIS

 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 );
 

INPUTS

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

RETURN VALUE

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

DESCRIPTION

 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.
 
libAfterImage/transform/mirror_asimage()

NAMEmirror_asimage()

SYNOPSIS

 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 );
 

INPUTS

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

RETURN VALUE

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

DESCRIPTION

 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.
 
libAfterImage/transform/pad_asimage()

NAMEpad_asimage()

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

SYNOPSIS

 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 );
 

INPUTS

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

RETURN VALUE

 returns newly created and encoded ASImage on success, NULL of failure.
 
libAfterImage/transform/blur_asimage_gauss()

NAMEblur_asimage_gauss()

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

SYNOPSIS

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

INPUTS

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

RETURN VALUE

 returns newly created and encoded ASImage on success, NULL of failure.
 
libAfterImage/transform/fill_asimage()

NAMEfill_asimage()

- Fills rectangle within the existing ASImage with specified color.

SYNOPSIS

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

INPUTS

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.

RETURN VALUE

 True on success, False on failure.
 
libAfterImage/transform/adjust_asimage_hsv()

NAMEadjust_asimage_hsv()

- adjusts image color properties in HSV colorspace

SYNOPSIS

 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);
 

INPUTS

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

RETURN VALUE

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

DESCRIPTION

 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.
 
libAfterImage/transform/colorize_asimage_vector()

NAMEcolorize_asimage_vector()

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

SYNOPSIS

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

INPUTS

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

RETURN VALUE

 True on success, False on failure.
 

DESCRIPTION

 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.
 
libAfterImage/transform/create_asimage_from_vector()

NAMEcreate_asimage_from_vector()

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

SYNOPSIS

 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 );
 

INPUTS

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

RETURN VALUE

 New ASImage  on success, NULL on failure.
 

SEE ALSO

 colorize_asimage_vector(), create_asimage(), set_asimage_vector()
 
libAfterImage/transform/slice_asimage2()

NAMEslice_asimage2()

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

SYNOPSIS

 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 );
 

INPUTS

asv
- pointer to valid ASVisual structure
src
- source ASImage.
slice_x_start
- ending of the left corners
slice_x_end
- beginning of the right corners
slice_y_start
- ending of the top corners
slice_y_end
- beginning 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.

RETURN VALUE

 New ASImage  on success, NULL on failure.
 

SEE ALSO

 scale_asimage(), tile_asimage()