Image::Leptonica::Func::colormap
version 0.03
colormap.c
colormap.c Colormap creation, copy, destruction, addition PIXCMAP *pixcmapCreate() PIXCMAP *pixcmapCreateRandom() PIXCMAP *pixcmapCreateLinear() PIXCMAP *pixcmapCopy() void pixcmapDestroy() l_int32 pixcmapAddColor() l_int32 pixcmapAddRGBA() l_int32 pixcmapAddNewColor() l_int32 pixcmapAddNearestColor() l_int32 pixcmapUsableColor() l_int32 pixcmapAddBlackOrWhite() l_int32 pixcmapSetBlackAndWhite() l_int32 pixcmapGetCount() l_int32 pixcmapGetDepth() l_int32 pixcmapGetMinDepth() l_int32 pixcmapGetFreeCount() l_int32 pixcmapClear() Colormap random access and test l_int32 pixcmapGetColor() l_int32 pixcmapGetColor32() l_int32 pixcmapGetRGBA() l_int32 pixcmapGetRGBA32() l_int32 pixcmapResetColor() l_int32 pixcmapGetIndex() l_int32 pixcmapHasColor() l_int32 pixcmapIsOpaque() l_int32 pixcmapCountGrayColors() l_int32 pixcmapGetRankIntensity() l_int32 pixcmapGetNearestIndex() l_int32 pixcmapGetNearestGrayIndex() l_int32 pixcmapGetComponentRange() l_int32 pixcmapGetExtremeValue() Colormap conversion PIXCMAP *pixcmapGrayToColor() PIXCMAP *pixcmapColorToGray() Colormap I/O l_int32 pixcmapReadStream() l_int32 pixcmapWriteStream() Extract colormap arrays and serialization l_int32 pixcmapToArrays() l_int32 pixcmapToRGBTable() l_int32 pixcmapSerializeToMemory() PIXCMAP *pixcmapDeserializeFromMemory() char *pixcmapConvertToHex() Colormap transforms l_int32 pixcmapGammaTRC() l_int32 pixcmapContrastTRC() l_int32 pixcmapShiftIntensity() l_int32 pixcmapShiftByComponent()
l_int32 pixcmapAddBlackOrWhite ( PIXCMAP *cmap, l_int32 color, l_int32 *pindex )
pixcmapAddBlackOrWhite() Input: cmap color (0 for black, 1 for white) &index (<optional return> index of color; can be null) Return: 0 if OK, 1 on error Notes: (1) This only adds color if not already there. (2) The alpha component is 255 (opaque) (3) This sets index to the requested color. (4) If there is no room in the colormap, returns the index of the closest color.
l_int32 pixcmapAddColor ( PIXCMAP *cmap, l_int32 rval, l_int32 gval, l_int32 bval )
pixcmapAddColor() Input: cmap rval, gval, bval (colormap entry to be added; each number is in range [0, ... 255]) Return: 0 if OK, 1 on error Notes: (1) This always adds the color if there is room. (2) The alpha component is 255 (opaque)
l_int32 pixcmapAddNearestColor ( PIXCMAP *cmap, l_int32 rval, l_int32 gval, l_int32 bval, l_int32 *pindex )
pixcmapAddNearestColor() Input: cmap rval, gval, bval (colormap entry to be added; each number is in range [0, ... 255]) &index (<return> index of color) Return: 0 if OK, 1 on error Notes: (1) This only adds color if not already there. (2) The alpha component is 255 (opaque) (3) If it's not in the colormap and there is no room to add another color, this returns the index of the nearest color.
l_int32 pixcmapAddNewColor ( PIXCMAP *cmap, l_int32 rval, l_int32 gval, l_int32 bval, l_int32 *pindex )
pixcmapAddNewColor() Input: cmap rval, gval, bval (colormap entry to be added; each number is in range [0, ... 255]) &index (<return> index of color) Return: 0 if OK, 1 on error; 2 if unable to add color Notes: (1) This only adds color if not already there. (2) The alpha component is 255 (opaque) (3) This returns the index of the new (or existing) color. (4) Returns 2 with a warning if unable to add this color; the caller should check the return value.
l_int32 pixcmapAddRGBA ( PIXCMAP *cmap, l_int32 rval, l_int32 gval, l_int32 bval, l_int32 aval )
pixcmapAddRGBA() Input: cmap rval, gval, bval, aval (colormap entry to be added; each number is in range [0, ... 255]) Return: 0 if OK, 1 on error Notes: (1) This always adds the color if there is room.
l_int32 pixcmapClear ( PIXCMAP *cmap )
pixcmapClear() Input: cmap Return: 0 if OK, 1 on error Note: this removes the colors by setting the count to 0.
PIXCMAP * pixcmapColorToGray ( PIXCMAP *cmaps, l_float32 rwt, l_float32 gwt, l_float32 bwt )
pixcmapColorToGray() Input: cmap rwt, gwt, bwt (non-negative; these should add to 1.0) Return: cmap (gray), or null on error Notes: (1) This creates a gray colormap from an arbitrary colormap. (2) In use, attach the output gray colormap to the pix (or a copy of it) that provided the input colormap.
l_int32 pixcmapContrastTRC ( PIXCMAP *cmap, l_float32 factor )
pixcmapContrastTRC() Input: colormap factor (generally between 0.0 (no enhancement) and 1.0, but can be larger than 1.0) Return: 0 if OK; 1 on error Notes: (1) This is an in-place transform (2) See pixContrastTRC() and numaContrastTRC() in enhance.c for description and use of transform
char * pixcmapConvertToHex ( l_uint8 *data, l_int32 ncolors )
pixcmapConvertToHex() Input: data (binary serialized data) ncolors (in colormap) Return: hexdata (bracketed, space-separated ascii hex string), or null on error. Notes: (1) The number of bytes in @data is 3 * ncolors. (2) Output is in form: < r0g0b0 r1g1b1 ... rngnbn > where r0, g0, b0 ... are each 2 bytes of hex ascii (3) This is used in pdf files to express the colormap as an array in ascii (human-readable) format.
PIXCMAP * pixcmapCopy ( PIXCMAP *cmaps )
pixcmapCopy() Input: cmaps Return: cmapd, or null on error
l_int32 pixcmapCountGrayColors ( PIXCMAP *cmap, l_int32 *pngray )
pixcmapCountGrayColors() Input: cmap &ngray (<return> number of gray colors) Return: 0 if OK, 1 on error Notes: (1) This counts the unique gray colors, including black and white.
PIXCMAP * pixcmapCreate ( l_int32 depth )
pixcmapCreate() Input: depth (bpp, of pix) Return: cmap, or null on error
PIXCMAP * pixcmapCreateLinear ( l_int32 d, l_int32 nlevels )
pixcmapCreateLinear() Input: d (depth of pix for this colormap; 1, 2, 4 or 8) nlevels (valid in range [2, 2^d]) Return: cmap, or null on error Notes: (1) Colormap has equally spaced gray color values from black (0, 0, 0) to white (255, 255, 255).
PIXCMAP * pixcmapCreateRandom ( l_int32 depth, l_int32 hasblack, l_int32 haswhite )
pixcmapCreateRandom() Input: depth (bpp, of pix; 2, 4 or 8) hasblack (1 if the first color is black; 0 if no black) haswhite (1 if the last color is white; 0 if no white) Return: cmap, or null on error Notes: (1) This sets up a colormap with random colors, where the first color is optionally black, the last color is optionally white, and the remaining colors are chosen randomly. (2) The number of randomly chosen colors is: 2^(depth) - haswhite - hasblack (3) Because rand() is seeded, it might disrupt otherwise deterministic results if also used elsewhere in a program. (4) rand() is not threadsafe, and will generate garbage if run on multiple threads at once -- though garbage is generally what you want from a random number generator! (5) Modern rand()s have equal randomness in low and high order bits, but older ones don't. Here, we're just using rand() to choose colors for output.
PIXCMAP * pixcmapDeserializeFromMemory ( l_uint8 *data, l_int32 cpc, l_int32 ncolors )
pixcmapDeserializeFromMemory() Input: data (binary string, 3 or 4 bytes per color) cpc (components/color: 3 for rgb, 4 for rgba) ncolors Return: cmap, or null on error
void pixcmapDestroy ( PIXCMAP **pcmap )
pixcmapDestroy() Input: &cmap (<set to null>) Return: void
l_int32 pixcmapGammaTRC ( PIXCMAP *cmap, l_float32 gamma, l_int32 minval, l_int32 maxval )
pixcmapGammaTRC() Input: colormap gamma (gamma correction; must be > 0.0) minval (input value that gives 0 for output; can be < 0) maxval (input value that gives 255 for output; can be > 255) Return: 0 if OK; 1 on error Notes: (1) This is an in-place transform (2) See pixGammaTRC() and numaGammaTRC() in enhance.c for description and use of transform
l_int32 pixcmapGetColor ( PIXCMAP *cmap, l_int32 index, l_int32 *prval, l_int32 *pgval, l_int32 *pbval )
pixcmapGetColor() Input: cmap index &rval, &gval, &bval (<return> each color value) Return: 0 if OK, 1 if not accessable (caller should check)
l_int32 pixcmapGetColor32 ( PIXCMAP *cmap, l_int32 index, l_uint32 *pval32 )
pixcmapGetColor32() Input: cmap index &val32 (<return> 32-bit rgb color value) Return: 0 if OK, 1 if not accessable (caller should check) Notes: (1) The returned alpha channel value is 0.
l_int32 pixcmapGetComponentRange ( PIXCMAP *cmap, l_int32 color, l_int32 *pminval, l_int32 *pmaxval )
pixcmapGetComponentRange() Input: cmap color (L_SELECT_RED, L_SELECT_GREEN or L_SELECT_BLUE) &minval (<optional return> minimum value of component) &maxval (<optional return> minimum value of component) Return: 0 if OK, 1 on error Notes: (1) Returns for selected components the extreme value (either min or max) of the color component that is found in the colormap.
l_int32 pixcmapGetCount ( PIXCMAP *cmap )
pixcmapGetCount() Input: cmap Return: count, or 0 on error
l_int32 pixcmapGetDepth ( PIXCMAP *cmap )
pixcmapGetDepth() Input: cmap Return: depth, or 0 on error
l_int32 pixcmapGetExtremeValue ( PIXCMAP *cmap, l_int32 type, l_int32 *prval, l_int32 *pgval, l_int32 *pbval )
pixcmapGetExtremeValue() Input: cmap type (L_SELECT_MIN or L_SELECT_MAX) &rval (<optional return> red component) &gval (<optional return> green component) &bval (<optional return> blue component) Return: 0 if OK, 1 on error Notes: (1) Returns for selected components the extreme value (either min or max) of the color component that is found in the colormap.
l_int32 pixcmapGetFreeCount ( PIXCMAP *cmap )
pixcmapGetFreeCount() Input: cmap Return: free entries, or 0 on error
l_int32 pixcmapGetIndex ( PIXCMAP *cmap, l_int32 rval, l_int32 gval, l_int32 bval, l_int32 *pindex )
pixcmapGetIndex() Input: cmap rval, gval, bval (colormap colors to search for; each number is in range [0, ... 255]) &index (<return>) Return: 0 if found, 1 if not found (caller must check)
l_int32 pixcmapGetMinDepth ( PIXCMAP *cmap, l_int32 *pmindepth )
pixcmapGetMinDepth() Input: cmap &mindepth (<return> minimum depth to support the colormap) Return: 0 if OK, 1 on error Notes: (1) On error, &mindepth is returned as 0.
l_int32 pixcmapGetNearestGrayIndex ( PIXCMAP *cmap, l_int32 val, l_int32 *pindex )
pixcmapGetNearestGrayIndex() Input: cmap val (gray value to search for; in range [0, ... 255]) &index (<return> the index of the nearest color) Return: 0 if OK, 1 on error (caller must check) Notes: (1) This should be used on gray colormaps. It uses only the green value of the colormap. (2) Returns the index of the exact color if possible, otherwise the index of the color closest to the target color.
l_int32 pixcmapGetNearestIndex ( PIXCMAP *cmap, l_int32 rval, l_int32 gval, l_int32 bval, l_int32 *pindex )
pixcmapGetNearestIndex() Input: cmap rval, gval, bval (colormap colors to search for; each number is in range [0, ... 255]) &index (<return> the index of the nearest color) Return: 0 if OK, 1 on error (caller must check) Notes: (1) Returns the index of the exact color if possible, otherwise the index of the color closest to the target color. (2) Nearest color is that which is the least sum-of-squares distance from the target color.
l_int32 pixcmapGetRGBA ( PIXCMAP *cmap, l_int32 index, l_int32 *prval, l_int32 *pgval, l_int32 *pbval, l_int32 *paval )
pixcmapGetRGBA() Input: cmap index &rval, &gval, &bval, &aval (<return> each color value) Return: 0 if OK, 1 if not accessable (caller should check)
l_int32 pixcmapGetRGBA32 ( PIXCMAP *cmap, l_int32 index, l_uint32 *pval32 )
pixcmapGetRGBA32() Input: cmap index &val32 (<return> 32-bit rgba color value) Return: 0 if OK, 1 if not accessable (caller should check)
l_int32 pixcmapGetRankIntensity ( PIXCMAP *cmap, l_float32 rankval, l_int32 *pindex )
pixcmapGetRankIntensity() Input: cmap rankval (0.0 for darkest, 1.0 for lightest color) &index (<return> the index into the colormap that corresponds to the rank intensity color) Return: 0 if OK, 1 on error
PIXCMAP * pixcmapGrayToColor ( l_uint32 color )
pixcmapGrayToColor() Input: color Return: cmap, or null on error Notes: (1) This creates a colormap that maps from gray to a specific color. In the mapping, each component is faded to white, depending on the gray value. (2) In use, this is simply attached to a grayscale pix to give it the input color.
l_int32 pixcmapHasColor ( PIXCMAP *cmap, l_int32 *pcolor )
pixcmapHasColor() Input: cmap &color (<return> TRUE if cmap has color; FALSE otherwise) Return: 0 if OK, 1 on error
l_int32 pixcmapIsOpaque ( PIXCMAP *cmap, l_int32 *popaque )
pixcmapIsOpaque() Input: cmap &opaque (<return> TRUE if fully opaque: all entries are 255) Return: 0 if OK, 1 on error
PIXCMAP * pixcmapReadStream ( FILE *fp )
pixcmapReadStream() Input: stream Return: cmap, or null on error
l_int32 pixcmapResetColor ( PIXCMAP *cmap, l_int32 index, l_int32 rval, l_int32 gval, l_int32 bval )
pixcmapResetColor() Input: cmap index rval, gval, bval (colormap entry to be reset; each number is in range [0, ... 255]) Return: 0 if OK, 1 if not accessable (caller should check) Notes: (1) This resets sets the color of an entry that has already been set and included in the count of colors. (2) The alpha component is 255 (opaque)
l_int32 pixcmapSerializeToMemory ( PIXCMAP *cmap, l_int32 cpc, l_int32 *pncolors, l_uint8 **pdata )
pixcmapSerializeToMemory() Input: colormap cpc (components/color: 3 for rgb, 4 for rgba) &ncolors (<return> number of colors in table) &data (<return> binary string, cpc bytes per color) Return: 0 if OK; 1 on error Notes: (1) When serializing to store in a pdf, use @cpc = 3.
l_int32 pixcmapSetBlackAndWhite ( PIXCMAP *cmap, l_int32 setblack, l_int32 setwhite )
pixcmapSetBlackAndWhite() Input: cmap setblack (0 for no operation; 1 to set darkest color to black) setwhite (0 for no operation; 1 to set lightest color to white) Return: 0 if OK, 1 on error
l_int32 pixcmapShiftByComponent ( PIXCMAP *cmap, l_uint32 srcval, l_uint32 dstval )
pixcmapShiftByComponent() Input: colormap srcval (source color: 0xrrggbb00) dstval (target color: 0xrrggbb00) Return: 0 if OK; 1 on error Notes: (1) This is an in-place transform (2) It implements pixelShiftByComponent() for each color. The mapping is specified by srcval and dstval. (3) If a component decreases, the component in the colormap decreases by the same ratio. Likewise for increasing, except all ratios are taken with respect to the distance from 255.
l_int32 pixcmapShiftIntensity ( PIXCMAP *cmap, l_float32 fraction )
pixcmapShiftIntensity() Input: colormap fraction (between -1.0 and +1.0) Return: 0 if OK; 1 on error Notes: (1) This is an in-place transform (2) It does a proportional shift of the intensity for each color. (3) If fraction < 0.0, it moves all colors towards (0,0,0). This darkens the image. If fraction > 0.0, it moves all colors towards (255,255,255) This fades the image. (4) The equivalent transform can be accomplished with pixcmapGammaTRC(), but it is considerably more difficult (see numaGammaTRC()).
l_int32 pixcmapToArrays ( PIXCMAP *cmap, l_int32 **prmap, l_int32 **pgmap, l_int32 **pbmap, l_int32 **pamap )
pixcmapToArrays() Input: colormap &rmap, &gmap, &bmap (<return> colormap arrays) &amap (<optional return> alpha array) Return: 0 if OK; 1 on error
l_int32 pixcmapToRGBTable ( PIXCMAP *cmap, l_uint32 **ptab, l_int32 *pncolors )
pixcmapToRGBTable() Input: colormap &tab (<return> table of rgba values for the colormap) &ncolors (<optional return> size of table) Return: 0 if OK; 1 on error
l_int32 pixcmapUsableColor ( PIXCMAP *cmap, l_int32 rval, l_int32 gval, l_int32 bval, l_int32 *pusable )
pixcmapUsableColor() Input: cmap rval, gval, bval (colormap entry to be added; each number is in range [0, ... 255]) usable (<return> 1 if usable; 0 if not) Return: 0 if OK, 1 on error Notes: (1) This checks if the color already exists or if there is room to add it. It makes no change in the colormap.
l_int32 pixcmapWriteStream ( FILE *fp, PIXCMAP *cmap )
pixcmapWriteStream() Input: stream, cmap Return: 0 if OK, 1 on error
Zakariyya Mughal <zmughal@cpan.org>
This software is copyright (c) 2014 by Zakariyya Mughal.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.
To install Image::Leptonica, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Image::Leptonica
CPAN shell
perl -MCPAN -e shell install Image::Leptonica
For more information on module installation, please visit the detailed CPAN module installation guide.