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Diffstat (limited to 'include/libnsgif.h')
| -rw-r--r-- | include/libnsgif.h | 183 |
1 files changed, 0 insertions, 183 deletions
diff --git a/include/libnsgif.h b/include/libnsgif.h deleted file mode 100644 index a819fec..0000000 --- a/include/libnsgif.h +++ /dev/null @@ -1,183 +0,0 @@ -/* - * Copyright 2004 Richard Wilson <richard.wilson@netsurf-browser.org> - * Copyright 2008 Sean Fox <dyntryx@gmail.com> - * - * This file is part of NetSurf's libnsgif, http://www.netsurf-browser.org/ - * Licenced under the MIT License, - * http://www.opensource.org/licenses/mit-license.php - */ - -/** - * \file - * Interface to progressive animated GIF file decoding. - */ - -#ifndef _LIBNSGIF_H_ -#define _LIBNSGIF_H_ - -#include <stdbool.h> -#include <inttypes.h> - -/* Error return values */ -typedef enum { - GIF_WORKING = 1, - GIF_OK = 0, - GIF_INSUFFICIENT_FRAME_DATA = -1, - GIF_FRAME_DATA_ERROR = -2, - GIF_INSUFFICIENT_DATA = -3, - GIF_DATA_ERROR = -4, - GIF_INSUFFICIENT_MEMORY = -5, - GIF_FRAME_NO_DISPLAY = -6, - GIF_END_OF_FRAME = -7 -} gif_result; - -/** GIF frame data */ -typedef struct gif_frame { - /** whether the frame should be displayed/animated */ - bool display; - /** delay (in cs) before animating the frame */ - unsigned int frame_delay; - - /* Internal members are listed below */ - - /** offset (in bytes) to the GIF frame data */ - unsigned int frame_pointer; - /** whether the frame has previously been used */ - bool virgin; - /** whether the frame is totally opaque */ - bool opaque; - /** whether a forcable screen redraw is required */ - bool redraw_required; - /** how the previous frame should be disposed; affects plotting */ - unsigned char disposal_method; - /** whether we acknoledge transparency */ - bool transparency; - /** the index designating a transparent pixel */ - unsigned char transparency_index; - /** x co-ordinate of redraw rectangle */ - unsigned int redraw_x; - /** y co-ordinate of redraw rectangle */ - unsigned int redraw_y; - /** width of redraw rectangle */ - unsigned int redraw_width; - /** height of redraw rectangle */ - unsigned int redraw_height; -} gif_frame; - -/* API for Bitmap callbacks */ -typedef void* (*gif_bitmap_cb_create)(int width, int height); -typedef void (*gif_bitmap_cb_destroy)(void *bitmap); -typedef unsigned char* (*gif_bitmap_cb_get_buffer)(void *bitmap); -typedef void (*gif_bitmap_cb_set_opaque)(void *bitmap, bool opaque); -typedef bool (*gif_bitmap_cb_test_opaque)(void *bitmap); -typedef void (*gif_bitmap_cb_modified)(void *bitmap); - -/** Bitmap callbacks function table */ -typedef struct gif_bitmap_callback_vt { - /** Create a bitmap. */ - gif_bitmap_cb_create bitmap_create; - /** Free a bitmap. */ - gif_bitmap_cb_destroy bitmap_destroy; - /** Return a pointer to the pixel data in a bitmap. */ - gif_bitmap_cb_get_buffer bitmap_get_buffer; - - /* Members below are optional */ - - /** Sets whether a bitmap should be plotted opaque. */ - gif_bitmap_cb_set_opaque bitmap_set_opaque; - /** Tests whether a bitmap has an opaque alpha channel. */ - gif_bitmap_cb_test_opaque bitmap_test_opaque; - /** The bitmap image has changed, so flush any persistant cache. */ - gif_bitmap_cb_modified bitmap_modified; -} gif_bitmap_callback_vt; - -/** GIF animation data */ -typedef struct gif_animation { - /** LZW decode context */ - void *lzw_ctx; - /** callbacks for bitmap functions */ - gif_bitmap_callback_vt bitmap_callbacks; - /** pointer to GIF data */ - unsigned char *gif_data; - /** width of GIF (may increase during decoding) */ - unsigned int width; - /** heigth of GIF (may increase during decoding) */ - unsigned int height; - /** number of frames decoded */ - unsigned int frame_count; - /** number of frames partially decoded */ - unsigned int frame_count_partial; - /** decoded frames */ - gif_frame *frames; - /** current frame decoded to bitmap */ - int decoded_frame; - /** currently decoded image; stored as bitmap from bitmap_create callback */ - void *frame_image; - /** number of times to loop animation */ - int loop_count; - - /* Internal members are listed below */ - - /** current index into GIF data */ - unsigned int buffer_position; - /** total number of bytes of GIF data available */ - unsigned int buffer_size; - /** current number of frame holders */ - unsigned int frame_holders; - /** index in the colour table for the background colour */ - unsigned int background_index; - /** image aspect ratio (ignored) */ - unsigned int aspect_ratio; - /** size of colour table (in entries) */ - unsigned int colour_table_size; - /** whether the GIF has a global colour table */ - bool global_colours; - /** global colour table */ - unsigned int *global_colour_table; - /** local colour table */ - unsigned int *local_colour_table; -} gif_animation; - -/** - * Initialises necessary gif_animation members. - */ -void gif_create(gif_animation *gif, gif_bitmap_callback_vt *bitmap_callbacks); - -/** - * Initialises any workspace held by the animation and attempts to decode - * any information that hasn't already been decoded. - * If an error occurs, all previously decoded frames are retained. - * - * @return Error return value. - * - GIF_FRAME_DATA_ERROR for GIF frame data error - * - GIF_INSUFFICIENT_FRAME_DATA for insufficient data to process - * any more frames - * - GIF_INSUFFICIENT_MEMORY for memory error - * - GIF_DATA_ERROR for GIF error - * - GIF_INSUFFICIENT_DATA for insufficient data to do anything - * - GIF_OK for successful decoding - * - GIF_WORKING for successful decoding if more frames are expected - */ -gif_result gif_initialise(gif_animation *gif, size_t size, unsigned char *data); - -/** - * Decodes a GIF frame. - * - * @return Error return value. If a frame does not contain any image data, - * GIF_OK is returned and gif->current_error is set to - * GIF_FRAME_NO_DISPLAY - * - GIF_FRAME_DATA_ERROR for GIF frame data error - * - GIF_INSUFFICIENT_FRAME_DATA for insufficient data to complete the frame - * - GIF_DATA_ERROR for GIF error (invalid frame header) - * - GIF_INSUFFICIENT_DATA for insufficient data to do anything - * - GIF_INSUFFICIENT_MEMORY for insufficient memory to process - * - GIF_OK for successful decoding - */ -gif_result gif_decode_frame(gif_animation *gif, unsigned int frame); - -/** - * Releases any workspace held by a gif - */ -void gif_finalise(gif_animation *gif); - -#endif |