/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0/LGPL 2.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is Mozilla Communicator client code. * * The Initial Developer of the Original Code is * Netscape Communications Corporation. * Portions created by the Initial Developer are Copyright (C) 1998 * the Initial Developer. All Rights Reserved. * * Contributor(s): * * Alternatively, the contents of this file may be used under the terms of * either the GNU General Public License Version 2 or later (the "GPL"), or * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), * in which case the provisions of the GPL or the LGPL are applicable instead * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** */ #ifndef _GIF_H_ #define _GIF_H_ #define MAX_LZW_BITS 12 #define MAX_BITS 4097 /* 2^MAX_LZW_BITS+1 */ #define MINIMUM_DELAY_TIME 100 #define MAX_COLORS 256 /* gif2.h The interface for the GIF87/89a decoder. */ // List of possible parsing states typedef enum { gif_gather, gif_init, //1 gif_type, gif_version, gif_global_header, gif_global_colormap, gif_image_start, //6 gif_image_header, gif_image_colormap, gif_image_body, gif_lzw_start, gif_lzw, //11 gif_sub_block, gif_extension, gif_control_extension, gif_consume_block, gif_skip_block, gif_done, //17 gif_oom, gif_error, gif_comment_extension, gif_application_extension, gif_netscape_extension_block, gif_consume_netscape_extension, gif_consume_comment, gif_delay, gif_stop_animating //added for animation stop } gstate; /* "Disposal" method indicates how the image should be handled in the framebuffer before the subsequent image is displayed. */ typedef enum { DISPOSE_NOT_SPECIFIED = 0, DISPOSE_KEEP = 1, /* Leave it in the framebuffer */ DISPOSE_OVERWRITE_BGCOLOR = 2, /* Overwrite with background color */ DISPOSE_OVERWRITE_PREVIOUS = 3 /* Save-under */ } gdispose; /* A GIF decoder's state */ typedef struct gif_struct { void* clientptr; /* Parsing state machine */ gstate state; /* Curent decoder master state */ PRUint8 *hold; /* Accumulation buffer */ PRUint8 *gather_head; /* Next byte to read in accumulation buffer */ int32 gather_request_size; /* Number of bytes to accumulate */ int32 gathered; /* bytes accumulated so far*/ gstate post_gather_state; /* State after requested bytes accumulated */ /* LZW decoder state machine */ PRUint8 *stackp; /* Current stack pointer */ int datasize; int codesize; int codemask; int clear_code; /* Codeword used to trigger dictionary reset */ int avail; /* Index of next available slot in dictionary */ int oldcode; PRUint8 firstchar; int count; /* Remaining # bytes in sub-block */ int bits; /* Number of unread bits in "datum" */ int32 datum; /* 32-bit input buffer */ /* Output state machine */ int ipass; /* Interlace pass; Ranges 1-4 if interlaced. */ PRUintn rows_remaining; /* Rows remaining to be output */ PRUintn irow; /* Current output row, starting at zero */ PRUint8 *rowbuf; /* Single scanline temporary buffer */ PRUint8 *rowend; /* Pointer to end of rowbuf */ PRUint8 *rowp; /* Current output pointer */ /* Parameters for image frame currently being decoded*/ PRUintn x_offset, y_offset; /* With respect to "screen" origin */ PRUintn height, width; int tpixel; /* Index of transparent pixel */ gdispose disposal_method; /* Restore to background, leave in place, etc.*/ PRUint8 *local_colormap; /* Per-image colormap */ int local_colormap_size; /* Size of local colormap array. */ PRUint32 delay_time; /* Display time, in milliseconds, for this image in a multi-image GIF */ /* Global (multi-image) state */ int screen_bgcolor; /* Logical screen background color */ int version; /* Either 89 for GIF89 or 87 for GIF87 */ PRUintn screen_width; /* Logical screen width & height */ PRUintn screen_height; int global_colormap_size; /* Size of global colormap array. */ int images_decoded; /* Counts images for multi-part GIFs */ int loop_count; /* Netscape specific extension block to control the number of animation loops a GIF renders. */ PRPackedBool progressive_display; /* If TRUE, do Haeberli interlace hack */ PRPackedBool interlaced; /* TRUE, if scanlines arrive interlaced order */ PRPackedBool is_transparent; /* TRUE, if tpixel is valid */ PRPackedBool is_local_colormap_defined; PRUint16 prefix[MAX_BITS]; /* LZW decoding tables */ PRUint8 global_colormap[3*MAX_COLORS]; /* Default colormap if local not supplied, 3 bytes for each color */ PRUint8 suffix[MAX_BITS]; /* LZW decoding tables */ PRUint8 stack[MAX_BITS]; /* Base of LZW decoder stack */ } gif_struct; /* These are the APIs that the client calls to intialize, push data to, and shut down the GIF decoder. */ PRBool GIFInit(gif_struct* gs, void* aClientData); void gif_destroy(gif_struct* aGIFStruct); PRStatus gif_write(gif_struct* aGIFStruct, const PRUint8 * buf, PRUint32 numbytes); PRBool gif_write_ready(const gif_struct* aGIFStruct); #endif