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sixel.h.in
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sixel.h.in
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/*
* Copyright (c) 2014-2020 Hayaki Saito
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
* the Software, and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <stddef.h> /* for size_t */
#ifndef LIBSIXEL_SIXEL_H
#define LIBSIXEL_SIXEL_H
#ifdef _WIN32
# define SIXELAPI __declspec(dllexport)
#else
# define SIXELAPI
#endif
#define LIBSIXEL_VERSION "@PACKAGE_VERSION@"
#define LIBSIXEL_ABI_VERSION "@LS_LTVERSION@"
typedef unsigned char sixel_index_t;
/* limitations */
#define SIXEL_OUTPUT_PACKET_SIZE 16384
#define SIXEL_PALETTE_MIN 2
#define SIXEL_PALETTE_MAX 256
#define SIXEL_USE_DEPRECATED_SYMBOLS 1
#define SIXEL_ALLOCATE_BYTES_MAX 10248UL * 1024UL * 128UL /* up to 128M */
#define SIXEL_WIDTH_LIMIT 1000000
#define SIXEL_HEIGHT_LIMIT 1000000
/* loader settings */
#define SIXEL_DEFALUT_GIF_DELAY 1
/* return value */
typedef int SIXELSTATUS;
#define SIXEL_OK 0x0000 /* succeeded */
#define SIXEL_FALSE 0x1000 /* failed */
#define SIXEL_RUNTIME_ERROR (SIXEL_FALSE | 0x0100) /* runtime error */
#define SIXEL_LOGIC_ERROR (SIXEL_FALSE | 0x0200) /* logic error */
#define SIXEL_FEATURE_ERROR (SIXEL_FALSE | 0x0300) /* feature not enabled */
#define SIXEL_LIBC_ERROR (SIXEL_FALSE | 0x0400) /* errors caused by curl */
#define SIXEL_CURL_ERROR (SIXEL_FALSE | 0x0500) /* errors occures in libc functions */
#define SIXEL_JPEG_ERROR (SIXEL_FALSE | 0x0600) /* errors occures in libjpeg functions */
#define SIXEL_PNG_ERROR (SIXEL_FALSE | 0x0700) /* errors occures in libpng functions */
#define SIXEL_GDK_ERROR (SIXEL_FALSE | 0x0800) /* errors occures in gdk functions */
#define SIXEL_GD_ERROR (SIXEL_FALSE | 0x0900) /* errors occures in gd functions */
#define SIXEL_STBI_ERROR (SIXEL_FALSE | 0x0a00) /* errors occures in stb_image functions */
#define SIXEL_STBIW_ERROR (SIXEL_FALSE | 0x0b00) /* errors occures in stb_image_write functions */
#define SIXEL_INTERRUPTED (SIXEL_OK | 0x0001) /* interrupted by a signal */
#define SIXEL_BAD_ALLOCATION (SIXEL_RUNTIME_ERROR | 0x0001) /* malloc() failed */
#define SIXEL_BAD_ARGUMENT (SIXEL_RUNTIME_ERROR | 0x0002) /* bad argument detected */
#define SIXEL_BAD_INPUT (SIXEL_RUNTIME_ERROR | 0x0003) /* bad input detected */
#define SIXEL_BAD_INTEGER_OVERFLOW (SIXEL_RUNTIME_ERROR | 0x0004) /* integer overflow */
#define SIXEL_NOT_IMPLEMENTED (SIXEL_FEATURE_ERROR | 0x0001) /* feature not implemented */
#define SIXEL_SUCCEEDED(status) (((status) & 0x1000) == 0)
#define SIXEL_FAILED(status) (((status) & 0x1000) != 0)
/* method for finding the largest dimension for splitting,
* and sorting by that component */
#define SIXEL_LARGE_AUTO 0x0 /* choose automatically the method for finding the largest
dimension */
#define SIXEL_LARGE_NORM 0x1 /* simply comparing the range in RGB space */
#define SIXEL_LARGE_LUM 0x2 /* transforming into luminosities before the comparison */
/* method for choosing a color from the box */
#define SIXEL_REP_AUTO 0x0 /* choose automatically the method for selecting
representative color from each box */
#define SIXEL_REP_CENTER_BOX 0x1 /* choose the center of the box */
#define SIXEL_REP_AVERAGE_COLORS 0x2 /* choose the average all the color
in the box (specified in Heckbert's paper) */
#define SIXEL_REP_AVERAGE_PIXELS 0x3 /* choose the average all the pixels in the box */
/* method for diffusing */
#define SIXEL_DIFFUSE_AUTO 0x0 /* choose diffusion type automatically */
#define SIXEL_DIFFUSE_NONE 0x1 /* don't diffuse */
#define SIXEL_DIFFUSE_ATKINSON 0x2 /* diffuse with Bill Atkinson's method */
#define SIXEL_DIFFUSE_FS 0x3 /* diffuse with Floyd-Steinberg method */
#define SIXEL_DIFFUSE_JAJUNI 0x4 /* diffuse with Jarvis, Judice & Ninke method */
#define SIXEL_DIFFUSE_STUCKI 0x5 /* diffuse with Stucki's method */
#define SIXEL_DIFFUSE_BURKES 0x6 /* diffuse with Burkes' method */
#define SIXEL_DIFFUSE_A_DITHER 0x7 /* positionally stable arithmetic dither */
#define SIXEL_DIFFUSE_X_DITHER 0x8 /* positionally stable arithmetic xor based dither */
/* quality modes */
#define SIXEL_QUALITY_AUTO 0x0 /* choose quality mode automatically */
#define SIXEL_QUALITY_HIGH 0x1 /* high quality palette construction */
#define SIXEL_QUALITY_LOW 0x2 /* low quality palette construction */
#define SIXEL_QUALITY_FULL 0x3 /* full quality palette construction */
#define SIXEL_QUALITY_HIGHCOLOR 0x4 /* high color */
/* built-in dither */
#define SIXEL_BUILTIN_MONO_DARK 0x0 /* monochrome terminal with dark background */
#define SIXEL_BUILTIN_MONO_LIGHT 0x1 /* monochrome terminal with light background */
#define SIXEL_BUILTIN_XTERM16 0x2 /* xterm 16color */
#define SIXEL_BUILTIN_XTERM256 0x3 /* xterm 256color */
#define SIXEL_BUILTIN_VT340_MONO 0x4 /* vt340 monochrome */
#define SIXEL_BUILTIN_VT340_COLOR 0x5 /* vt340 color */
#define SIXEL_BUILTIN_G1 0x6 /* 1bit grayscale */
#define SIXEL_BUILTIN_G2 0x7 /* 2bit grayscale */
#define SIXEL_BUILTIN_G4 0x8 /* 4bit grayscale */
#define SIXEL_BUILTIN_G8 0x9 /* 8bit grayscale */
/* offset value of pixelFormat */
#define SIXEL_FORMATTYPE_COLOR (0)
#define SIXEL_FORMATTYPE_GRAYSCALE (1 << 6)
#define SIXEL_FORMATTYPE_PALETTE (1 << 7)
/* pixelformat type of input image
NOTE: for compatibility, the value of PIXELFORAMT_COLOR_RGB888 must be 3 */
#define SIXEL_PIXELFORMAT_RGB555 (SIXEL_FORMATTYPE_COLOR | 0x01) /* 15bpp */
#define SIXEL_PIXELFORMAT_RGB565 (SIXEL_FORMATTYPE_COLOR | 0x02) /* 16bpp */
#define SIXEL_PIXELFORMAT_RGB888 (SIXEL_FORMATTYPE_COLOR | 0x03) /* 24bpp */
#define SIXEL_PIXELFORMAT_BGR555 (SIXEL_FORMATTYPE_COLOR | 0x04) /* 15bpp */
#define SIXEL_PIXELFORMAT_BGR565 (SIXEL_FORMATTYPE_COLOR | 0x05) /* 16bpp */
#define SIXEL_PIXELFORMAT_BGR888 (SIXEL_FORMATTYPE_COLOR | 0x06) /* 24bpp */
#define SIXEL_PIXELFORMAT_ARGB8888 (SIXEL_FORMATTYPE_COLOR | 0x10) /* 32bpp */
#define SIXEL_PIXELFORMAT_RGBA8888 (SIXEL_FORMATTYPE_COLOR | 0x11) /* 32bpp */
#define SIXEL_PIXELFORMAT_ABGR8888 (SIXEL_FORMATTYPE_COLOR | 0x12) /* 32bpp */
#define SIXEL_PIXELFORMAT_BGRA8888 (SIXEL_FORMATTYPE_COLOR | 0x13) /* 32bpp */
#define SIXEL_PIXELFORMAT_G1 (SIXEL_FORMATTYPE_GRAYSCALE | 0x00) /* 1bpp grayscale */
#define SIXEL_PIXELFORMAT_G2 (SIXEL_FORMATTYPE_GRAYSCALE | 0x01) /* 2bpp grayscale */
#define SIXEL_PIXELFORMAT_G4 (SIXEL_FORMATTYPE_GRAYSCALE | 0x02) /* 4bpp grayscale */
#define SIXEL_PIXELFORMAT_G8 (SIXEL_FORMATTYPE_GRAYSCALE | 0x03) /* 8bpp grayscale */
#define SIXEL_PIXELFORMAT_AG88 (SIXEL_FORMATTYPE_GRAYSCALE | 0x13) /* 16bpp gray+alpha */
#define SIXEL_PIXELFORMAT_GA88 (SIXEL_FORMATTYPE_GRAYSCALE | 0x23) /* 16bpp gray+alpha */
#define SIXEL_PIXELFORMAT_PAL1 (SIXEL_FORMATTYPE_PALETTE | 0x00) /* 1bpp palette */
#define SIXEL_PIXELFORMAT_PAL2 (SIXEL_FORMATTYPE_PALETTE | 0x01) /* 2bpp palette */
#define SIXEL_PIXELFORMAT_PAL4 (SIXEL_FORMATTYPE_PALETTE | 0x02) /* 4bpp palette */
#define SIXEL_PIXELFORMAT_PAL8 (SIXEL_FORMATTYPE_PALETTE | 0x03) /* 8bpp palette */
/* palette type */
#define SIXEL_PALETTETYPE_AUTO 0 /* choose palette type automatically */
#define SIXEL_PALETTETYPE_HLS 1 /* HLS colorspace */
#define SIXEL_PALETTETYPE_RGB 2 /* RGB colorspace */
/* policies of SIXEL encoding */
#define SIXEL_ENCODEPOLICY_AUTO 0 /* choose encoding policy automatically */
#define SIXEL_ENCODEPOLICY_FAST 1 /* encode as fast as possible */
#define SIXEL_ENCODEPOLICY_SIZE 2 /* encode to as small sixel sequence as possible */
/* method for re-sampling */
#define SIXEL_RES_NEAREST 0 /* Use nearest neighbor method */
#define SIXEL_RES_GAUSSIAN 1 /* Use guaussian filter */
#define SIXEL_RES_HANNING 2 /* Use hanning filter */
#define SIXEL_RES_HAMMING 3 /* Use hamming filter */
#define SIXEL_RES_BILINEAR 4 /* Use bilinear filter */
#define SIXEL_RES_WELSH 5 /* Use welsh filter */
#define SIXEL_RES_BICUBIC 6 /* Use bicubic filter */
#define SIXEL_RES_LANCZOS2 7 /* Use lanczos-2 filter */
#define SIXEL_RES_LANCZOS3 8 /* Use lanczos-3 filter */
#define SIXEL_RES_LANCZOS4 9 /* Use lanczos-4 filter */
/* image format */
#define SIXEL_FORMAT_GIF 0x0 /* read only */
#define SIXEL_FORMAT_PNG 0x1 /* read/write */
#define SIXEL_FORMAT_BMP 0x2 /* read only */
#define SIXEL_FORMAT_JPG 0x3 /* read only */
#define SIXEL_FORMAT_TGA 0x4 /* read only */
#define SIXEL_FORMAT_WBMP 0x5 /* read only with --with-gd configure option */
#define SIXEL_FORMAT_TIFF 0x6 /* read only */
#define SIXEL_FORMAT_SIXEL 0x7 /* read only */
#define SIXEL_FORMAT_PNM 0x8 /* read only */
#define SIXEL_FORMAT_GD2 0x9 /* read only with --with-gd configure option */
#define SIXEL_FORMAT_PSD 0xa /* read only */
#define SIXEL_FORMAT_HDR 0xb /* read only */
/* loop mode */
#define SIXEL_LOOP_AUTO 0 /* honer the setting of GIF header */
#define SIXEL_LOOP_FORCE 1 /* always enable loop */
#define SIXEL_LOOP_DISABLE 2 /* always disable loop */
/* setopt flags */
#define SIXEL_OPTFLAG_INPUT ('i') /* -i, --input: specify input file name. */
#define SIXEL_OPTFLAG_OUTPUT ('o') /* -o, --output: specify output file name. */
#define SIXEL_OPTFLAG_OUTFILE ('o') /* -o, --outfile: specify output file name. */
#define SIXEL_OPTFLAG_7BIT_MODE ('7') /* -7, --7bit-mode: for 7bit terminals or printers (default) */
#define SIXEL_OPTFLAG_8BIT_MODE ('8') /* -8, --8bit-mode: for 8bit terminals or printers */
#define SIXEL_OPTFLAG_HAS_GRI_ARG_LIMIT ('R') /* -R, --gri-limit: limit arguments of DECGRI('!') to 255 */
#define SIXEL_OPTFLAG_COLORS ('p') /* -p COLORS, --colors=COLORS: specify number of colors */
#define SIXEL_OPTFLAG_MAPFILE ('m') /* -m FILE, --mapfile=FILE: specify set of colors */
#define SIXEL_OPTFLAG_MONOCHROME ('e') /* -e, --monochrome: output monochrome sixel image */
#define SIXEL_OPTFLAG_INSECURE ('k') /* -k, --insecure: allow to connect to SSL sites without certs */
#define SIXEL_OPTFLAG_INVERT ('i') /* -i, --invert: assume the terminal background color */
#define SIXEL_OPTFLAG_HIGH_COLOR ('I') /* -I, --high-color: output 15bpp sixel image */
#define SIXEL_OPTFLAG_USE_MACRO ('u') /* -u, --use-macro: use DECDMAC and DEVINVM sequences */
#define SIXEL_OPTFLAG_MACRO_NUMBER ('n') /* -n MACRONO, --macro-number=MACRONO:
specify macro register number */
#define SIXEL_OPTFLAG_COMPLEXION_SCORE ('C') /* -C COMPLEXIONSCORE, --complexion-score=COMPLEXIONSCORE:
specify an number argument for the score of
complexion correction. */
#define SIXEL_OPTFLAG_IGNORE_DELAY ('g') /* -g, --ignore-delay: render GIF animation without delay */
#define SIXEL_OPTFLAG_STATIC ('S') /* -S, --static: render animated GIF as a static image */
#define SIXEL_OPTFLAG_DIFFUSION ('d') /* -d DIFFUSIONTYPE, --diffusion=DIFFUSIONTYPE:
choose diffusion method which used with -p option.
DIFFUSIONTYPE is one of them:
auto -> choose diffusion type
automatically (default)
none -> do not diffuse
fs -> Floyd-Steinberg method
atkinson -> Bill Atkinson's method
jajuni -> Jarvis, Judice & Ninke
stucki -> Stucki's method
burkes -> Burkes' method
a_dither -> positionally stable
arithmetic dither
a_dither -> positionally stable
arithmetic xor based dither
*/
#define SIXEL_OPTFLAG_FIND_LARGEST ('f') /* -f FINDTYPE, --find-largest=FINDTYPE:
choose method for finding the largest
dimension of median cut boxes for
splitting, make sense only when -p
option (color reduction) is
specified
FINDTYPE is one of them:
auto -> choose finding method
automatically (default)
norm -> simply comparing the
range in RGB space
lum -> transforming into
luminosities before the
comparison
*/
#define SIXEL_OPTFLAG_SELECT_COLOR ('s') /* -s SELECTTYPE, --select-color=SELECTTYPE
choose the method for selecting
representative color from each
median-cut box, make sense only
when -p option (color reduction) is
specified
SELECTTYPE is one of them:
auto -> choose selecting
method automatically
(default)
center -> choose the center of
the box
average -> calculate the color
average into the box
histogram -> similar with average
but considers color
histogram
*/
#define SIXEL_OPTFLAG_CROP ('c') /* -c REGION, --crop=REGION:
crop source image to fit the
specified geometry. REGION should
be formatted as '%dx%d+%d+%d'
*/
#define SIXEL_OPTFLAG_WIDTH ('w') /* -w WIDTH, --width=WIDTH:
resize image to specified width
WIDTH is represented by the
following syntax
auto -> preserving aspect
ratio (default)
<number>% -> scale width with
given percentage
<number> -> scale width with
pixel counts
<number>px -> scale width with
pixel counts
*/
#define SIXEL_OPTFLAG_HEIGHT ('h') /* -h HEIGHT, --height=HEIGHT:
resize image to specified height
HEIGHT is represented by the
following syntax
auto -> preserving aspect
ratio (default)
<number>% -> scale height with
given percentage
<number> -> scale height with
pixel counts
<number>px -> scale height with
pixel counts
*/
#define SIXEL_OPTFLAG_RESAMPLING ('r') /* -r RESAMPLINGTYPE, --resampling=RESAMPLINGTYPE:
choose resampling filter used
with -w or -h option (scaling)
RESAMPLINGTYPE is one of them:
nearest -> Nearest-Neighbor
method
gaussian -> Gaussian filter
hanning -> Hanning filter
hamming -> Hamming filter
bilinear -> Bilinear filter
(default)
welsh -> Welsh filter
bicubic -> Bicubic filter
lanczos2 -> Lanczos-2 filter
lanczos3 -> Lanczos-3 filter
lanczos4 -> Lanczos-4 filter
*/
#define SIXEL_OPTFLAG_QUALITY ('q') /* -q QUALITYMODE, --quality=QUALITYMODE:
select quality of color
quanlization.
auto -> decide quality mode
automatically (default)
low -> low quality and high
speed mode
high -> high quality and low
speed mode
full -> full quality and careful
speed mode
*/
#define SIXEL_OPTFLAG_LOOPMODE ('l') /* -l LOOPMODE, --loop-control=LOOPMODE:
select loop control mode for GIF
animation.
auto -> honor the setting of
GIF header (default)
force -> always enable loop
disable -> always disable loop
*/
#define SIXEL_OPTFLAG_PALETTE_TYPE ('t') /* -t PALETTETYPE, --palette-type=PALETTETYPE:
select palette color space type
auto -> choose palette type
automatically (default)
hls -> use HLS color space
rgb -> use RGB color space
*/
#define SIXEL_OPTFLAG_BUILTIN_PALETTE ('b') /* -b BUILTINPALETTE, --builtin-palette=BUILTINPALETTE:
select built-in palette type
xterm16 -> X default 16 color map
xterm256 -> X default 256 color map
vt340mono -> VT340 monochrome map
vt340color -> VT340 color map
gray1 -> 1bit grayscale map
gray2 -> 2bit grayscale map
gray4 -> 4bit grayscale map
gray8 -> 8bit grayscale map
*/
#define SIXEL_OPTFLAG_ENCODE_POLICY ('E') /* -E ENCODEPOLICY, --encode-policy=ENCODEPOLICY:
select encoding policy
auto -> choose encoding policy
automatically (default)
fast -> encode as fast as possible
size -> encode to as small sixel
sequence as possible
*/
#define SIXEL_OPTFLAG_BGCOLOR ('B') /* -B BGCOLOR, --bgcolor=BGCOLOR:
specify background color
BGCOLOR is represented by the
following syntax
#rgb
#rrggbb
#rrrgggbbb
#rrrrggggbbbb
rgb:r/g/b
rgb:rr/gg/bb
rgb:rrr/ggg/bbb
rgb:rrrr/gggg/bbbb
*/
#define SIXEL_OPTFLAG_PENETRATE ('P') /* -P, --penetrate:
penetrate GNU Screen using DCS
pass-through sequence */
#define SIXEL_OPTFLAG_PIPE_MODE ('D') /* -D, --pipe-mode: (deprecated)
read source images from stdin continuously */
#define SIXEL_OPTFLAG_VERBOSE ('v') /* -v, --verbose: show debugging info */
#define SIXEL_OPTFLAG_VERSION ('V') /* -V, --version: show version and license info */
#define SIXEL_OPTFLAG_HELP ('H') /* -H, --help: show this help */
#if SIXEL_USE_DEPRECATED_SYMBOLS
/* output character size */
enum characterSize {
CSIZE_7BIT = 0, /* 7bit character */
CSIZE_8BIT = 1 /* 8bit character */
};
/* method for finding the largest dimension for splitting,
* and sorting by that component */
enum methodForLargest {
LARGE_AUTO = 0, /* choose automatically the method for finding the largest
dimension */
LARGE_NORM = 1, /* simply comparing the range in RGB space */
LARGE_LUM = 2 /* transforming into luminosities before the comparison */
};
/* method for choosing a color from the box */
enum methodForRep {
REP_AUTO = 0, /* choose automatically the method for selecting
representative color from each box */
REP_CENTER_BOX = 1, /* choose the center of the box */
REP_AVERAGE_COLORS = 2, /* choose the average all the color
in the box (specified in Heckbert's paper) */
REP_AVERAGE_PIXELS = 3 /* choose the average all the pixels in the box */
};
/* method for diffusing */
enum methodForDiffuse {
DIFFUSE_AUTO = 0, /* choose diffusion type automatically */
DIFFUSE_NONE = 1, /* don't diffuse */
DIFFUSE_ATKINSON = 2, /* diffuse with Bill Atkinson's method */
DIFFUSE_FS = 3, /* diffuse with Floyd-Steinberg method */
DIFFUSE_JAJUNI = 4, /* diffuse with Jarvis, Judice & Ninke method */
DIFFUSE_STUCKI = 5, /* diffuse with Stucki's method */
DIFFUSE_BURKES = 6, /* diffuse with Burkes' method */
DIFFUSE_A_DITHER = 7, /* positionally stable arithmetic dither */
DIFFUSE_X_DITHER = 8 /* positionally stable arithmetic xor based dither */
};
/* quality modes */
enum qualityMode {
QUALITY_AUTO = 0, /* choose quality mode automatically */
QUALITY_HIGH = 1, /* high quality palette construction */
QUALITY_LOW = 2, /* low quality palette construction */
QUALITY_FULL = 3, /* full quality palette construction */
QUALITY_HIGHCOLOR = 4 /* high color */
};
/* built-in dither */
enum builtinDither {
BUILTIN_MONO_DARK = 0, /* monochrome terminal with dark background */
BUILTIN_MONO_LIGHT = 1, /* monochrome terminal with dark background */
BUILTIN_XTERM16 = 2, /* xterm 16color */
BUILTIN_XTERM256 = 3, /* xterm 256color */
BUILTIN_VT340_MONO = 4, /* vt340 monochrome */
BUILTIN_VT340_COLOR = 5 /* vt340 color */
};
/* offset value of enum pixelFormat */
enum formatType {
FORMATTYPE_COLOR = 0,
FORMATTYPE_GRAYSCALE = 1 << 6,
FORMATTYPE_PALETTE = 1 << 7
};
/* pixelformat type of input image
NOTE: for compatibility, the value of PIXELFORAMT_COLOR_RGB888 must be 3 */
enum pixelFormat {
PIXELFORMAT_RGB555 = FORMATTYPE_COLOR | 0x01, /* 15bpp */
PIXELFORMAT_RGB565 = FORMATTYPE_COLOR | 0x02, /* 16bpp */
PIXELFORMAT_RGB888 = FORMATTYPE_COLOR | 0x03, /* 24bpp */
PIXELFORMAT_BGR555 = FORMATTYPE_COLOR | 0x04, /* 15bpp */
PIXELFORMAT_BGR565 = FORMATTYPE_COLOR | 0x05, /* 16bpp */
PIXELFORMAT_BGR888 = FORMATTYPE_COLOR | 0x06, /* 24bpp */
PIXELFORMAT_ARGB8888 = FORMATTYPE_COLOR | 0x10, /* 32bpp */
PIXELFORMAT_RGBA8888 = FORMATTYPE_COLOR | 0x11, /* 32bpp */
PIXELFORMAT_G1 = FORMATTYPE_GRAYSCALE | 0x00, /* 1bpp grayscale */
PIXELFORMAT_G2 = FORMATTYPE_GRAYSCALE | 0x01, /* 2bpp grayscale */
PIXELFORMAT_G4 = FORMATTYPE_GRAYSCALE | 0x02, /* 4bpp grayscale */
PIXELFORMAT_G8 = FORMATTYPE_GRAYSCALE | 0x03, /* 8bpp grayscale */
PIXELFORMAT_AG88 = FORMATTYPE_GRAYSCALE | 0x13, /* 16bpp gray+alpha */
PIXELFORMAT_GA88 = FORMATTYPE_GRAYSCALE | 0x23, /* 16bpp gray+alpha */
PIXELFORMAT_PAL1 = FORMATTYPE_PALETTE | 0x00, /* 1bpp palette */
PIXELFORMAT_PAL2 = FORMATTYPE_PALETTE | 0x01, /* 2bpp palette */
PIXELFORMAT_PAL4 = FORMATTYPE_PALETTE | 0x02, /* 4bpp palette */
PIXELFORMAT_PAL8 = FORMATTYPE_PALETTE | 0x03 /* 8bpp palette */
};
/* palette type */
enum paletteType {
PALETTETYPE_AUTO = 0, /* choose palette type automatically */
PALETTETYPE_HLS = 1, /* HLS colorspace */
PALETTETYPE_RGB = 2 /* RGB colorspace */
};
/* policies of SIXEL encoding */
enum encodePolicy {
ENCODEPOLICY_AUTO = 0, /* choose encoding policy automatically */
ENCODEPOLICY_FAST = 1, /* encode as fast as possible */
ENCODEPOLICY_SIZE = 2 /* encode to as small sixel sequence as possible */
};
/* method for re-sampling */
enum methodForResampling {
RES_NEAREST = 0, /* Use nearest neighbor method */
RES_GAUSSIAN = 1, /* Use guaussian filter */
RES_HANNING = 2, /* Use hanning filter */
RES_HAMMING = 3, /* Use hamming filter */
RES_BILINEAR = 4, /* Use bilinear filter */
RES_WELSH = 5, /* Use welsh filter */
RES_BICUBIC = 6, /* Use bicubic filter */
RES_LANCZOS2 = 7, /* Use lanczos-2 filter */
RES_LANCZOS3 = 8, /* Use lanczos-3 filter */
RES_LANCZOS4 = 9 /* Use lanczos-4 filter */
};
#endif
typedef void *(* sixel_malloc_t)(size_t);
typedef void *(* sixel_calloc_t)(size_t, size_t);
typedef void *(* sixel_realloc_t)(void *, size_t);
typedef void (* sixel_free_t)(void *);
struct sixel_allocator;
typedef struct sixel_allocator sixel_allocator_t;
#ifdef __cplusplus
extern "C" {
#endif
/* create allocator object */
SIXELSTATUS
sixel_allocator_new(
sixel_allocator_t /* out */ **ppallocator, /* allocator object to be created */
sixel_malloc_t /* in */ fn_malloc, /* custom malloc() function */
sixel_calloc_t /* in */ fn_calloc, /* custom calloc() function */
sixel_realloc_t /* in */ fn_realloc, /* custom realloc() function */
sixel_free_t /* in */ fn_free); /* custom free() function */
/* increase reference count of allocator object (thread-unsafe) */
SIXELAPI void
sixel_allocator_ref(
sixel_allocator_t /* in */ *allocator); /* allocator object to be
increment reference counter */
/* decrease reference count of output context object (thread-unsafe) */
SIXELAPI void
sixel_allocator_unref(sixel_allocator_t *allocator);
/* call custom malloc() */
SIXELAPI void *
sixel_allocator_malloc(
sixel_allocator_t /* in */ *allocator, /* allocator object */
size_t /* in */ n); /* allocation size */
/* call custom calloc() */
SIXELAPI void *
sixel_allocator_calloc(
sixel_allocator_t /* in */ *allocator, /* allocator object */
size_t /* in */ nelm, /* allocation size */
size_t /* in */ elsize); /* allocation size */
/* call custom realloc() */
SIXELAPI void *
sixel_allocator_realloc(
sixel_allocator_t /* in */ *allocator, /* allocator object */
void /* in */ *p, /* existing buffer to be re-allocated */
size_t /* in */ n); /* re-allocation size */
/* call custom free() */
SIXELAPI void
sixel_allocator_free(
sixel_allocator_t /* in */ *allocator, /* allocator object */
void /* in */ *p); /* existing buffer to be freed */
#ifdef HAVE_TESTS
extern volatile int sixel_debug_malloc_counter;
void *
sixel_bad_malloc(size_t size);
void *
sixel_bad_calloc(size_t count, size_t size);
void *
sixel_bad_realloc(void *ptr, size_t size);
#endif /* HAVE_TESTS */
#ifdef __cplusplus
}
#endif
/* output context manipulation API */
struct sixel_output;
typedef struct sixel_output sixel_output_t;
typedef int (* sixel_write_function)(char *data, int size, void *priv);
#ifdef __cplusplus
extern "C" {
#endif
/* create new output context object */
SIXELAPI SIXELSTATUS
sixel_output_new(
sixel_output_t /* out */ **output, /* output object to be created */
sixel_write_function /* in */ fn_write, /* callback for output sixel */
void /* in */ *priv, /* private data given as
3rd argument of fn_write */
sixel_allocator_t /* in */ *allocator); /* allocator, null if you use
default allocator */
/* deprecated: create an output object */
SIXELAPI @attr_func_deprecated@ sixel_output_t *
sixel_output_create(
sixel_write_function /* in */ fn_write, /* callback for output sixel */
void /* in */ *priv); /* private data given as
3rd argument of fn_write */
/* destroy output context object */
SIXELAPI void
sixel_output_destroy(sixel_output_t /* in */ *output); /* output context */
/* increase reference count of output context object (thread-unsafe) */
SIXELAPI void
sixel_output_ref(sixel_output_t /* in */ *output); /* output context */
/* decrease reference count of output context object (thread-unsafe) */
SIXELAPI void
sixel_output_unref(sixel_output_t /* in */ *output); /* output context */
/* get 8bit output mode which indicates whether it uses C1 control characters */
SIXELAPI int
sixel_output_get_8bit_availability(
sixel_output_t /* in */ *output); /* output context */
/* set 8bit output mode state */
SIXELAPI void
sixel_output_set_8bit_availability(
sixel_output_t /* in */ *output, /* output context */
int /* in */ availability); /* 0: do not use 8bit characters
1: use 8bit characters */
/* set whether limit arguments of DECGRI('!') to 255 */
SIXELAPI void
sixel_output_set_gri_arg_limit(
sixel_output_t /* in */ *output, /* output context */
int /* in */ value); /* 0: don't limit arguments of DECGRI
1: limit arguments of DECGRI to 255 */
/* set GNU Screen penetration feature enable or disable */
SIXELAPI void
sixel_output_set_penetrate_multiplexer(
sixel_output_t /* in */ *output, /* output context */
int /* in */ penetrate); /* 0: penetrate GNU Screen
1: do not penetrate GNU Screen */
/* set whether we skip DCS envelope */
SIXELAPI void
sixel_output_set_skip_dcs_envelope(
sixel_output_t /* in */ *output, /* output context */
int /* in */ skip); /* 0: output DCS envelope
1: do not output DCS envelope */
/* set palette type: RGB or HLS */
SIXELAPI void
sixel_output_set_palette_type(
sixel_output_t /* in */ *output, /* output context */
int /* in */ palettetype); /* PALETTETYPE_RGB: RGB palette
PALETTETYPE_HLS: HLS palette */
/* set encodeing policy: auto, fast or size */
SIXELAPI void
sixel_output_set_encode_policy(
sixel_output_t /* in */ *output, /* output context */
int /* in */ encode_policy);
#ifdef __cplusplus
}
#endif
/* color quantization API */
/* handle type of dither context object */
struct sixel_dither;
typedef struct sixel_dither sixel_dither_t;
#ifdef __cplusplus
extern "C" {
#endif
/* create dither context object */
SIXELAPI SIXELSTATUS
sixel_dither_new(
sixel_dither_t /* out */ **ppdither, /* dither object to be created */
int /* in */ ncolors, /* required colors */
sixel_allocator_t /* in */ *allocator); /* allocator, null if you use
default allocator */
/* create dither context object */
SIXELAPI @attr_func_deprecated@ sixel_dither_t *
sixel_dither_create(int /* in */ ncolors); /* number of colors */
/* get built-in dither context object */
SIXELAPI sixel_dither_t *
sixel_dither_get(int builtin_dither); /* ID of built-in dither object */
/* destroy dither context object */
SIXELAPI void
sixel_dither_destroy(sixel_dither_t *dither); /* dither context object */
/* increase reference count of dither context object (thread-unsafe) */
SIXELAPI void
sixel_dither_ref(sixel_dither_t *dither); /* dither context object */
/* decrease reference count of dither context object (thread-unsafe) */
SIXELAPI void
sixel_dither_unref(sixel_dither_t *dither); /* dither context object */
/* initialize internal palette from specified pixel buffer */
SIXELAPI SIXELSTATUS
sixel_dither_initialize(
sixel_dither_t *dither, /* dither context object */
unsigned char /* in */ *data, /* sample image */
int /* in */ width, /* image width */
int /* in */ height, /* image height */
int /* in */ pixelformat, /* one of enum pixelFormat */
int /* in */ method_for_largest, /* method for finding the largest dimension */
int /* in */ method_for_rep, /* method for choosing a color from the box */
int /* in */ quality_mode); /* quality of histogram processing */
/* set diffusion type, choose from enum methodForDiffuse */
SIXELAPI void
sixel_dither_set_diffusion_type(
sixel_dither_t /* in */ *dither, /* dither context object */
int /* in */ method_for_diffuse); /* one of enum methodForDiffuse */
/* get number of palette colors */
SIXELAPI int
sixel_dither_get_num_of_palette_colors(
sixel_dither_t /* in */ *dither); /* dither context object */
/* get number of histogram colors */
SIXELAPI int
sixel_dither_get_num_of_histogram_colors(
sixel_dither_t /* in */ *dither); /* dither context object */
SIXELAPI @attr_func_deprecated@ int /* typoed! remains for compatibility. */
sixel_dither_get_num_of_histgram_colors(
sixel_dither_t /* in */ *dither); /* dither context object */
/* get palette */
SIXELAPI unsigned char *
sixel_dither_get_palette(
sixel_dither_t /* in */ *dither); /* dither context object */
/* set palette */
SIXELAPI void
sixel_dither_set_palette(
sixel_dither_t /* in */ *dither, /* dither context object */
unsigned char /* in */ *palette);
/* set the factor of complexion color correcting */
SIXELAPI void
sixel_dither_set_complexion_score(
sixel_dither_t /* in */ *dither, /* dither context object */
int /* in */ score); /* complexion score (>= 1) */
/* set whether omitting palette difinition */
SIXELAPI void
sixel_dither_set_body_only(
sixel_dither_t /* in */ *dither, /* dither context object */
int /* in */ bodyonly); /* 0: output palette section(default)
1: do not output palette section */
/* set whether optimize palette size */
SIXELAPI void
sixel_dither_set_optimize_palette(
sixel_dither_t /* in */ *dither, /* dither context object */
int /* in */ do_opt); /* 0: optimize palette size
1: don't optimize palette size */
/* set pixelformat */
SIXELAPI void
sixel_dither_set_pixelformat(
sixel_dither_t /* in */ *dither, /* dither context object */
int /* in */ pixelformat); /* one of enum pixelFormat */
/* set transparent */
SIXELAPI void
sixel_dither_set_transparent(
sixel_dither_t /* in */ *dither, /* dither context object */
int /* in */ transparent); /* transparent color index */
#ifdef __cplusplus
}
#endif
/* converter API */
typedef void * (* sixel_allocator_function)(size_t size);
#ifdef __cplusplus
extern "C" {
#endif
/* convert pixels into sixel format and write it to output context */
SIXELAPI SIXELSTATUS
sixel_encode(
unsigned char /* in */ *pixels, /* pixel bytes */
int /* in */ width, /* image width */
int /* in */ height, /* image height */
int /* in */ depth, /* color depth: now unused */
sixel_dither_t /* in */ *dither, /* dither context */
sixel_output_t /* in */ *context); /* output context */
/* convert sixel data into indexed pixel bytes and palette data */
SIXELAPI SIXELSTATUS
sixel_decode_raw(
unsigned char /* in */ *p, /* sixel bytes */
int /* in */ len, /* size of sixel bytes */
unsigned char /* out */ **pixels, /* decoded pixels */
int /* out */ *pwidth, /* image width */
int /* out */ *pheight, /* image height */
unsigned char /* out */ **palette, /* ARGB palette */
int /* out */ *ncolors, /* palette size (<= 256) */
sixel_allocator_t /* in */ *allocator); /* allocator object or null */
SIXELAPI @attr_func_deprecated@ SIXELSTATUS
sixel_decode(
unsigned char /* in */ *sixels, /* sixel bytes */
int /* in */ size, /* size of sixel bytes */
unsigned char /* out */ **pixels, /* decoded pixels */
int /* out */ *pwidth, /* image width */
int /* out */ *pheight, /* image height */
unsigned char /* out */ **palette, /* RGBA palette */
int /* out */ *ncolors, /* palette size (<= 256) */
sixel_allocator_function /* in */ fn_malloc); /* malloc function */
#ifdef __cplusplus
}
#endif
/* helper API */
#ifdef __cplusplus
extern "C" {
#endif
SIXELAPI void
sixel_helper_set_additional_message(
const char /* in */ *message /* error message */
);
SIXELAPI char const *
sixel_helper_get_additional_message(void);
/* convert error status code int formatted string */
SIXELAPI char const *
sixel_helper_format_error(
SIXELSTATUS /* in */ status /* status code */
);
/* compute pixel depth from pixelformat */
SIXELAPI int
sixel_helper_compute_depth(
int /* in */ pixelformat /* one of enum pixelFormat */
);
/* convert pixelFormat into PIXELFORMAT_RGB888 */
SIXELAPI SIXELSTATUS
sixel_helper_normalize_pixelformat(
unsigned char /* out */ *dst, /* destination buffer */
int /* out */ *dst_pixelformat, /* converted pixelformat */
unsigned char const /* in */ *src, /* source pixels */
int /* in */ src_pixelformat, /* format of source image */
int /* in */ width, /* width of source image */
int /* in */ height /* height of source image */
);
/* scale image to specified size */
SIXELAPI SIXELSTATUS
sixel_helper_scale_image(
unsigned char /* out */ *dst, /* destination buffer */
unsigned char const /* in */ *src, /* source image data */
int /* in */ srcw, /* source image width */
int /* in */ srch, /* source image height */
int /* in */ pixelformat, /* one of enum pixelFormat */
int /* in */ dstw, /* destination image width */
int /* in */ dsth, /* destination image height */
int /* in */ method_for_resampling, /* one of methodForResampling */
sixel_allocator_t /* in */ *allocator /* allocator object */
);
#ifdef __cplusplus
}
#endif
/* image loader/writer API */
#if SIXEL_USE_DEPRECATED_SYMBOLS
enum imageFormat {
FORMAT_GIF = 0, /* read only */
FORMAT_PNG = 1, /* read/write */
FORMAT_BMP = 2, /* read only */
FORMAT_JPG = 3, /* read only */
FORMAT_TGA = 4, /* read only */
FORMAT_WBMP = 5, /* read only with --with-gd configure option */
FORMAT_TIFF = 6, /* read only */
FORMAT_SIXEL = 7, /* read only */
FORMAT_PNM = 8, /* read only */
FORMAT_GD2 = 9, /* read only with --with-gd configure option */
FORMAT_PSD = 10, /* read only */
FORMAT_HDR = 11 /* read only */
};
/* loop mode */
enum loopControl {
LOOP_AUTO = 0, /* honer the setting of GIF header */
LOOP_FORCE = 1, /* always enable loop */
LOOP_DISABLE = 2 /* always disable loop */
};
#endif
/* handle type of dither context object */
struct sixel_frame;
typedef struct sixel_frame sixel_frame_t;
#ifdef __cplusplus
extern "C" {
#endif
/* constructor of frame object */
SIXELAPI SIXELSTATUS
sixel_frame_new(
sixel_frame_t /* out */ **ppframe, /* frame object to be created */
sixel_allocator_t /* in */ *allocator); /* allocator, null if you use
default allocator */
/* deprecated version of sixel_frame_new() */
SIXELAPI @attr_func_deprecated@ sixel_frame_t *
sixel_frame_create(void);
/* increase reference count of frame object (thread-unsafe) */
SIXELAPI void
sixel_frame_ref(sixel_frame_t /* in */ *frame);
/* decrease reference count of frame object (thread-unsafe) */
SIXELAPI void
sixel_frame_unref(sixel_frame_t /* in */ *frame);
/* initialize frame object with a pixel buffer */
SIXELAPI SIXELSTATUS
sixel_frame_init(
sixel_frame_t /* in */ *frame, /* frame object to be initialize */
unsigned char /* in */ *pixels, /* pixel buffer */
int /* in */ width, /* pixel width of buffer */
int /* in */ height, /* pixel height of buffer */
int /* in */ pixelformat, /* pixelformat of buffer */
unsigned char /* in */ *palette, /* palette for buffer or NULL */
int /* in */ ncolors /* number of palette colors or (-1) */
);
/* get pixels */
SIXELAPI unsigned char *
sixel_frame_get_pixels(sixel_frame_t /* in */ *frame); /* frame object */
/* get palette */
SIXELAPI unsigned char *
sixel_frame_get_palette(sixel_frame_t /* in */ *frame); /* frame object */
/* get width */
SIXELAPI int
sixel_frame_get_width(sixel_frame_t /* in */ *frame); /* frame object */
/* get height */
SIXELAPI int
sixel_frame_get_height(sixel_frame_t /* in */ *frame); /* frame object */
/* get ncolors */
SIXELAPI int
sixel_frame_get_ncolors(sixel_frame_t /* in */ *frame); /* frame object */
/* get pixelformat */
SIXELAPI int
sixel_frame_get_pixelformat(sixel_frame_t /* in */ *frame); /* frame object */
/* get transparent */
SIXELAPI int
sixel_frame_get_transparent(sixel_frame_t /* in */ *frame); /* frame object */
/* get transparent */
SIXELAPI int
sixel_frame_get_multiframe(sixel_frame_t /* in */ *frame); /* frame object */
/* get delay */
SIXELAPI int
sixel_frame_get_delay(sixel_frame_t /* in */ *frame); /* frame object */
/* get frame no */
SIXELAPI int
sixel_frame_get_frame_no(sixel_frame_t /* in */ *frame); /* frame object */
/* get loop no */
SIXELAPI int
sixel_frame_get_loop_no(sixel_frame_t /* in */ *frame); /* frame object */
/* strip alpha from RGBA/ARGB formatted pixbuf */
SIXELAPI int
sixel_frame_strip_alpha(
sixel_frame_t /* in */ *frame,
unsigned char /* in */ *bgcolor);
/* resize a frame to given size with specified resampling filter */
SIXELAPI SIXELSTATUS
sixel_frame_resize(
sixel_frame_t /* in */ *frame,
int /* in */ width,
int /* in */ height,
int /* in */ method_for_resampling);
/* clip frame */
SIXELAPI SIXELSTATUS
sixel_frame_clip(