1/******************************************************************************
2
3gif_lib.h - service library for decoding and encoding GIF images
4
5*****************************************************************************/
6
7#ifndef _GIF_LIB_H_
8#define _GIF_LIB_H_ 1
9
10#ifdef __cplusplus
11extern "C" {
12#endif /* __cplusplus */
13
14#define GIFLIB_MAJOR 5
15#define GIFLIB_MINOR 1
16#define GIFLIB_RELEASE 0
17
18#define GIF_ERROR 0
19#define GIF_OK 1
20
21#include <stddef.h>
22#include <stdbool.h>
23
24#define GIF_STAMP "GIFVER" /* First chars in file - GIF stamp. */
25#define GIF_STAMP_LEN sizeof(GIF_STAMP) - 1
26#define GIF_VERSION_POS 3 /* Version first character in stamp. */
27#define GIF87_STAMP "GIF87a" /* First chars in file - GIF stamp. */
28#define GIF89_STAMP "GIF89a" /* First chars in file - GIF stamp. */
29
30typedef unsigned char GifPixelType;
31typedef unsigned char *GifRowType;
32typedef unsigned char GifByteType;
33typedef unsigned int GifPrefixType;
34typedef int GifWord;
35
36typedef struct GifColorType {
37 GifByteType Red, Green, Blue;
38} GifColorType;
39
40typedef struct ColorMapObject {
41 int ColorCount;
42 int BitsPerPixel;
43 bool SortFlag;
44 GifColorType *Colors; /* on malloc(3) heap */
45} ColorMapObject;
46
47typedef struct GifImageDesc {
48 GifWord Left, Top, Width, Height; /* Current image dimensions. */
49 bool Interlace; /* Sequential/Interlaced lines. */
50 ColorMapObject *ColorMap; /* The local color map */
51} GifImageDesc;
52
53typedef struct ExtensionBlock {
54 int ByteCount;
55 GifByteType *Bytes; /* on malloc(3) heap */
56 int Function; /* The block function code */
57#define CONTINUE_EXT_FUNC_CODE 0x00 /* continuation subblock */
58#define COMMENT_EXT_FUNC_CODE 0xfe /* comment */
59#define GRAPHICS_EXT_FUNC_CODE 0xf9 /* graphics control (GIF89) */
60#define PLAINTEXT_EXT_FUNC_CODE 0x01 /* plaintext */
61#define APPLICATION_EXT_FUNC_CODE 0xff /* application block */
62} ExtensionBlock;
63
64typedef struct SavedImage {
65 GifImageDesc ImageDesc;
66 GifByteType *RasterBits; /* on malloc(3) heap */
67 int ExtensionBlockCount; /* Count of extensions before image */
68 ExtensionBlock *ExtensionBlocks; /* Extensions before image */
69} SavedImage;
70
71typedef struct GifFileType {
72 GifWord SWidth, SHeight; /* Size of virtual canvas */
73 GifWord SColorResolution; /* How many colors can we generate? */
74 GifWord SBackGroundColor; /* Background color for virtual canvas */
75 GifByteType AspectByte; /* Used to compute pixel aspect ratio */
76 ColorMapObject *SColorMap; /* Global colormap, NULL if nonexistent. */
77 int ImageCount; /* Number of current image (both APIs) */
78 GifImageDesc Image; /* Current image (low-level API) */
79 SavedImage *SavedImages; /* Image sequence (high-level API) */
80 int ExtensionBlockCount; /* Count extensions past last image */
81 ExtensionBlock *ExtensionBlocks; /* Extensions past last image */
82 int Error; /* Last error condition reported */
83 void *UserData; /* hook to attach user data (TVT) */
84 void *Private; /* Don't mess with this! */
85} GifFileType;
86
87#define GIF_ASPECT_RATIO(n) ((n)+15.0/64.0)
88
89typedef enum {
90 UNDEFINED_RECORD_TYPE,
91 SCREEN_DESC_RECORD_TYPE,
92 IMAGE_DESC_RECORD_TYPE, /* Begin with ',' */
93 EXTENSION_RECORD_TYPE, /* Begin with '!' */
94 TERMINATE_RECORD_TYPE /* Begin with ';' */
95} GifRecordType;
96
97/* func type to read gif data from arbitrary sources (TVT) */
98typedef int (*InputFunc) (GifFileType *, GifByteType *, int);
99
100/* func type to write gif data to arbitrary targets.
101 * Returns count of bytes written. (MRB)
102 */
103typedef int (*OutputFunc) (GifFileType *, const GifByteType *, int);
104
105/******************************************************************************
106 GIF89 structures
107******************************************************************************/
108
109typedef struct GraphicsControlBlock {
110 int DisposalMode;
111#define DISPOSAL_UNSPECIFIED 0 /* No disposal specified. */
112#define DISPOSE_DO_NOT 1 /* Leave image in place */
113#define DISPOSE_BACKGROUND 2 /* Set area too background color */
114#define DISPOSE_PREVIOUS 3 /* Restore to previous content */
115 bool UserInputFlag; /* User confirmation required before disposal */
116 int DelayTime; /* pre-display delay in 0.01sec units */
117 int TransparentColor; /* Palette index for transparency, -1 if none */
118#define NO_TRANSPARENT_COLOR -1
119} GraphicsControlBlock;
120
121/******************************************************************************
122 GIF encoding routines
123******************************************************************************/
124
125/* Main entry points */
126GifFileType *EGifOpenFileName(const char *GifFileName,
127 const bool GifTestExistence, int *Error);
128GifFileType *EGifOpenFileHandle(const int GifFileHandle, int *Error);
129GifFileType *EGifOpen(void *userPtr, OutputFunc writeFunc, int *Error);
130int EGifSpew(GifFileType * GifFile);
131const char *EGifGetGifVersion(GifFileType *GifFile); /* new in 5.x */
132int EGifCloseFile(GifFileType *GifFile, int *ErrorCode);
133
134#define E_GIF_SUCCEEDED 0
135#define E_GIF_ERR_OPEN_FAILED 1 /* And EGif possible errors. */
136#define E_GIF_ERR_WRITE_FAILED 2
137#define E_GIF_ERR_HAS_SCRN_DSCR 3
138#define E_GIF_ERR_HAS_IMAG_DSCR 4
139#define E_GIF_ERR_NO_COLOR_MAP 5
140#define E_GIF_ERR_DATA_TOO_BIG 6
141#define E_GIF_ERR_NOT_ENOUGH_MEM 7
142#define E_GIF_ERR_DISK_IS_FULL 8
143#define E_GIF_ERR_CLOSE_FAILED 9
144#define E_GIF_ERR_NOT_WRITEABLE 10
145
146/* These are legacy. You probably do not want to call them directly */
147int EGifPutScreenDesc(GifFileType *GifFile,
148 const int GifWidth, const int GifHeight,
149 const int GifColorRes,
150 const int GifBackGround,
151 const ColorMapObject *GifColorMap);
152int EGifPutImageDesc(GifFileType *GifFile,
153 const int GifLeft, const int GifTop,
154 const int GifWidth, const int GifHeight,
155 const bool GifInterlace,
156 const ColorMapObject *GifColorMap);
157void EGifSetGifVersion(GifFileType *GifFile, const bool gif89);
158int EGifPutLine(GifFileType *GifFile, GifPixelType *GifLine,
159 int GifLineLen);
160int EGifPutPixel(GifFileType *GifFile, const GifPixelType GifPixel);
161int EGifPutComment(GifFileType *GifFile, const char *GifComment);
162int EGifPutExtensionLeader(GifFileType *GifFile, const int GifExtCode);
163int EGifPutExtensionBlock(GifFileType *GifFile,
164 const int GifExtLen, const void *GifExtension);
165int EGifPutExtensionTrailer(GifFileType *GifFile);
166int EGifPutExtension(GifFileType *GifFile, const int GifExtCode,
167 const int GifExtLen,
168 const void *GifExtension);
169int EGifPutCode(GifFileType *GifFile, int GifCodeSize,
170 const GifByteType *GifCodeBlock);
171int EGifPutCodeNext(GifFileType *GifFile,
172 const GifByteType *GifCodeBlock);
173
174/******************************************************************************
175 GIF decoding routines
176******************************************************************************/
177
178/* Main entry points */
179GifFileType *DGifOpenFileName(const char *GifFileName, int *Error);
180GifFileType *DGifOpenFileHandle(int GifFileHandle, int *Error);
181int DGifSlurp(GifFileType * GifFile);
182GifFileType *DGifOpen(void *userPtr, InputFunc readFunc, int *Error); /* new one (TVT) */
183 int DGifCloseFile(GifFileType * GifFile, int *ErrorCode);
184
185#define D_GIF_SUCCEEDED 0
186#define D_GIF_ERR_OPEN_FAILED 101 /* And DGif possible errors. */
187#define D_GIF_ERR_READ_FAILED 102
188#define D_GIF_ERR_NOT_GIF_FILE 103
189#define D_GIF_ERR_NO_SCRN_DSCR 104
190#define D_GIF_ERR_NO_IMAG_DSCR 105
191#define D_GIF_ERR_NO_COLOR_MAP 106
192#define D_GIF_ERR_WRONG_RECORD 107
193#define D_GIF_ERR_DATA_TOO_BIG 108
194#define D_GIF_ERR_NOT_ENOUGH_MEM 109
195#define D_GIF_ERR_CLOSE_FAILED 110
196#define D_GIF_ERR_NOT_READABLE 111
197#define D_GIF_ERR_IMAGE_DEFECT 112
198#define D_GIF_ERR_EOF_TOO_SOON 113
199
200/* These are legacy. You probably do not want to call them directly */
201int DGifGetScreenDesc(GifFileType *GifFile);
202int DGifGetRecordType(GifFileType *GifFile, GifRecordType *GifType);
203int DGifGetImageDesc(GifFileType *GifFile);
204int DGifGetLine(GifFileType *GifFile, GifPixelType *GifLine, int GifLineLen);
205int DGifGetPixel(GifFileType *GifFile, GifPixelType GifPixel);
206int DGifGetComment(GifFileType *GifFile, char *GifComment);
207int DGifGetExtension(GifFileType *GifFile, int *GifExtCode,
208 GifByteType **GifExtension);
209int DGifGetExtensionNext(GifFileType *GifFile, GifByteType **GifExtension);
210int DGifGetCode(GifFileType *GifFile, int *GifCodeSize,
211 GifByteType **GifCodeBlock);
212int DGifGetCodeNext(GifFileType *GifFile, GifByteType **GifCodeBlock);
213int DGifGetLZCodes(GifFileType *GifFile, int *GifCode);
214
215
216/******************************************************************************
217 Color table quantization (deprecated)
218******************************************************************************/
219int GifQuantizeBuffer(unsigned int Width, unsigned int Height,
220 int *ColorMapSize, GifByteType * RedInput,
221 GifByteType * GreenInput, GifByteType * BlueInput,
222 GifByteType * OutputBuffer,
223 GifColorType * OutputColorMap);
224
225/******************************************************************************
226 Error handling and reporting.
227******************************************************************************/
228extern const char *GifErrorString(int ErrorCode); /* new in 2012 - ESR */
229
230/*****************************************************************************
231 Everything below this point is new after version 1.2, supporting `slurp
232 mode' for doing I/O in two big belts with all the image-bashing in core.
233******************************************************************************/
234
235/******************************************************************************
236 Color map handling from gif_alloc.c
237******************************************************************************/
238
239extern ColorMapObject *GifMakeMapObject(int ColorCount,
240 const GifColorType *ColorMap);
241extern void GifFreeMapObject(ColorMapObject *Object);
242extern ColorMapObject *GifUnionColorMap(const ColorMapObject *ColorIn1,
243 const ColorMapObject *ColorIn2,
244 GifPixelType ColorTransIn2[]);
245extern int GifBitSize(int n);
246
247/******************************************************************************
248 Support for the in-core structures allocation (slurp mode).
249******************************************************************************/
250
251extern void GifApplyTranslation(SavedImage *Image, GifPixelType Translation[]);
252extern int GifAddExtensionBlock(int *ExtensionBlock_Count,
253 ExtensionBlock **ExtensionBlocks,
254 int Function,
255 unsigned int Len, unsigned char ExtData[]);
256extern void GifFreeExtensions(int *ExtensionBlock_Count,
257 ExtensionBlock **ExtensionBlocks);
258extern SavedImage *GifMakeSavedImage(GifFileType *GifFile,
259 const SavedImage *CopyFrom);
260extern void GifFreeSavedImages(GifFileType *GifFile);
261
262/******************************************************************************
263 5.x functions for GIF89 graphics control blocks
264******************************************************************************/
265
266int DGifExtensionToGCB(const size_t GifExtensionLength,
267 const GifByteType *GifExtension,
268 GraphicsControlBlock *GCB);
269size_t EGifGCBToExtension(const GraphicsControlBlock *GCB,
270 GifByteType *GifExtension);
271
272int DGifSavedExtensionToGCB(GifFileType *GifFile,
273 int ImageIndex,
274 GraphicsControlBlock *GCB);
275int EGifGCBToSavedExtension(const GraphicsControlBlock *GCB,
276 GifFileType *GifFile,
277 int ImageIndex);
278
279/******************************************************************************
280 The library's internal utility font
281******************************************************************************/
282
283#define GIF_FONT_WIDTH 8
284#define GIF_FONT_HEIGHT 8
285extern const unsigned char GifAsciiTable8x8[][GIF_FONT_WIDTH];
286
287extern void GifDrawText8x8(SavedImage *Image,
288 const int x, const int y,
289 const char *legend, const int color);
290
291extern void GifDrawBox(SavedImage *Image,
292 const int x, const int y,
293 const int w, const int d, const int color);
294
295extern void GifDrawRectangle(SavedImage *Image,
296 const int x, const int y,
297 const int w, const int d, const int color);
298
299extern void GifDrawBoxedText8x8(SavedImage *Image,
300 const int x, const int y,
301 const char *legend,
302 const int border, const int bg, const int fg);
303
304#ifdef __cplusplus
305}
306#endif /* __cplusplus */
307#endif /* _GIF_LIB_H */
308
309/* end */
310