177 lines
6.6 KiB
C
177 lines
6.6 KiB
C
/*
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* Gif extracting routines - derived from libungif
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*
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* Portions Copyright 2006 Mike McCormack
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
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*/
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/*
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* Original copyright notice:
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*
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* The GIFLIB distribution is Copyright (c) 1997 Eric S. Raymond
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*/
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/******************************************************************************
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* In order to make life a little bit easier when using the GIF file format,
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* this library was written, and which does all the dirty work...
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*
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* Written by Gershon Elber, Jun. 1989
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* Hacks by Eric S. Raymond, Sep. 1992
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******************************************************************************
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* History:
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* 14 Jun 89 - Version 1.0 by Gershon Elber.
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* 3 Sep 90 - Version 1.1 by Gershon Elber (Support for Gif89, Unique names)
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* 15 Sep 90 - Version 2.0 by Eric S. Raymond (Changes to support GIF slurp)
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* 26 Jun 96 - Version 3.0 by Eric S. Raymond (Full GIF89 support)
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* 17 Dec 98 - Version 4.0 by Toshio Kuratomi (Fix extension writing code)
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*****************************************************************************/
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#ifndef _UNGIF_H_
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#define _UNGIF_H_ 1
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#define GIF_ERROR 0
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#define GIF_OK 1
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#ifndef TRUE
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#define TRUE 1
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#endif /* TRUE */
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#ifndef FALSE
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#define FALSE 0
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#endif /* FALSE */
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#ifndef NULL
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#define NULL 0
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#endif /* NULL */
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#define GIF_STAMP "GIFVER" /* First chars in file - GIF stamp. */
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#define GIF_STAMP_LEN sizeof(GIF_STAMP) - 1
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#define GIF_VERSION_POS 3 /* Version first character in stamp. */
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#define GIF87_STAMP "GIF87a" /* First chars in file - GIF stamp. */
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#define GIF89_STAMP "GIF89a" /* First chars in file - GIF stamp. */
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#define GIF_FILE_BUFFER_SIZE 16384 /* Files uses bigger buffers than usual. */
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typedef int GifBooleanType;
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typedef unsigned char GifPixelType;
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typedef unsigned char *GifRowType;
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typedef unsigned char GifByteType;
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typedef unsigned int GifPrefixType;
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typedef int GifWord;
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typedef struct GifColorType {
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GifByteType Red, Green, Blue;
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} GifColorType;
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typedef struct ColorMapObject {
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int ColorCount;
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int BitsPerPixel;
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int SortFlag;
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GifColorType *Colors;
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} ColorMapObject;
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typedef struct GifImageDesc {
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GifWord Left, Top, Width, Height, /* Current image dimensions. */
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Interlace; /* Sequential/Interlaced lines. */
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ColorMapObject *ColorMap; /* The local color map */
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} GifImageDesc;
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/* This is the in-core version of an extension record */
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typedef struct {
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int Function; /* Holds the type of the Extension block. */
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int ByteCount;
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char *Bytes;
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} ExtensionBlock;
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typedef struct {
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int Function; /* DEPRECATED: Use ExtensionBlocks[x].Function instead */
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int ExtensionBlockCount;
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ExtensionBlock *ExtensionBlocks;
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} Extensions;
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typedef struct GifFileType {
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GifWord SWidth, SHeight, /* Screen dimensions. */
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SColorResolution, /* How many colors can we generate? */
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SBackGroundColor, /* I hope you understand this one... */
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SAspectRatio; /* Pixel aspect ratio, in 1/64 units, starting at 1:4. */
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ColorMapObject *SColorMap; /* NULL if not exists. */
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Extensions Extensions;
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int ImageCount; /* Number of current image */
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GifImageDesc Image; /* Block describing current image */
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struct SavedImage *SavedImages; /* Use this to accumulate file state */
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void *UserData; /* hook to attach user data (TVT) */
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void *Private; /* Don't mess with this! */
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} GifFileType;
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typedef enum {
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UNDEFINED_RECORD_TYPE,
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SCREEN_DESC_RECORD_TYPE,
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IMAGE_DESC_RECORD_TYPE, /* Begin with ',' */
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EXTENSION_RECORD_TYPE, /* Begin with '!' */
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TERMINATE_RECORD_TYPE /* Begin with ';' */
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} GifRecordType;
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/* func type to read gif data from arbitrary sources (TVT) */
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typedef int (*InputFunc) (GifFileType *, GifByteType *, int);
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/* GIF89 extension function codes */
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#define COMMENT_EXT_FUNC_CODE 0xfe /* comment */
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#define GRAPHICS_EXT_FUNC_CODE 0xf9 /* graphics control */
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#define PLAINTEXT_EXT_FUNC_CODE 0x01 /* plaintext */
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#define APPLICATION_EXT_FUNC_CODE 0xff /* application block */
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/* public interface to ungif.c */
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int DGifSlurp(GifFileType * GifFile) DECLSPEC_HIDDEN;
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GifFileType *DGifOpen(void *userPtr, InputFunc readFunc) DECLSPEC_HIDDEN;
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int DGifCloseFile(GifFileType * GifFile) DECLSPEC_HIDDEN;
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#define D_GIF_ERR_OPEN_FAILED 101 /* And DGif possible errors. */
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#define D_GIF_ERR_READ_FAILED 102
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#define D_GIF_ERR_NOT_GIF_FILE 103
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#define D_GIF_ERR_NO_SCRN_DSCR 104
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#define D_GIF_ERR_NO_IMAG_DSCR 105
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#define D_GIF_ERR_NO_COLOR_MAP 106
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#define D_GIF_ERR_WRONG_RECORD 107
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#define D_GIF_ERR_DATA_TOO_BIG 108
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#define D_GIF_ERR_NOT_ENOUGH_MEM 109
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#define D_GIF_ERR_CLOSE_FAILED 110
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#define D_GIF_ERR_NOT_READABLE 111
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#define D_GIF_ERR_IMAGE_DEFECT 112
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#define D_GIF_ERR_EOF_TOO_SOON 113
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/******************************************************************************
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* Support for the in-core structures allocation (slurp mode).
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*****************************************************************************/
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/* This holds an image header, its unpacked raster bits, and extensions */
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typedef struct SavedImage {
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GifImageDesc ImageDesc;
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unsigned char *RasterBits;
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Extensions Extensions;
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} SavedImage;
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#endif /* _UNGIF_H_ */
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