1 /******************************************************************************
2
3 gif_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
11 extern "C" {
12 #endif /* __cplusplus */
13
14 #define GIFLIB_MAJOR 5
15 #define GIFLIB_MINOR 1
16 #define GIFLIB_RELEASE 8
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
30 typedef unsigned char GifPixelType;
31 typedef unsigned char *GifRowType;
32 typedef unsigned char GifByteType;
33 typedef unsigned int GifPrefixType;
34 typedef int GifWord;
35
36 typedef struct GifColorType {
37 GifByteType Red, Green, Blue;
38 } GifColorType;
39
40 typedef struct ColorMapObject {
41 int ColorCount;
42 int BitsPerPixel;
43 bool SortFlag;
44 GifColorType *Colors; /* on malloc(3) heap */
45 } ColorMapObject;
46
47 typedef 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
53 typedef 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 (GIF89) */
62 } ExtensionBlock;
63
64 typedef 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
71 typedef 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
89 typedef 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) */
98 typedef int (*InputFunc) (GifFileType *, GifByteType *, int);
99
100 /* func type to write gif data to arbitrary targets.
101 * Returns count of bytes written. (MRB)
102 */
103 typedef int (*OutputFunc) (GifFileType *, const GifByteType *, int);
104
105 /******************************************************************************
106 GIF89 structures
107 ******************************************************************************/
108
109 typedef 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 */
126 GifFileType *EGifOpenFileName(const char *GifFileName,
127 const bool GifTestExistence, int *Error);
128 GifFileType *EGifOpenFileHandle(const int GifFileHandle, int *Error);
129 GifFileType *EGifOpen(void *userPtr, OutputFunc writeFunc, int *Error);
130 int EGifSpew(GifFileType * GifFile);
131 const char *EGifGetGifVersion(GifFileType *GifFile); /* new in 5.x */
132 int 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 */
147 int EGifPutScreenDesc(GifFileType *GifFile,
148 const int GifWidth, const int GifHeight,
149 const int GifColorRes,
150 const int GifBackGround,
151 const ColorMapObject *GifColorMap);
152 int 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);
157 void EGifSetGifVersion(GifFileType *GifFile, const bool gif89);
158 int EGifPutLine(GifFileType *GifFile, GifPixelType *GifLine,
159 int GifLineLen);
160 int EGifPutPixel(GifFileType *GifFile, const GifPixelType GifPixel);
161 int EGifPutComment(GifFileType *GifFile, const char *GifComment);
162 int EGifPutExtensionLeader(GifFileType *GifFile, const int GifExtCode);
163 int EGifPutExtensionBlock(GifFileType *GifFile,
164 const int GifExtLen, const void *GifExtension);
165 int EGifPutExtensionTrailer(GifFileType *GifFile);
166 int EGifPutExtension(GifFileType *GifFile, const int GifExtCode,
167 const int GifExtLen,
168 const void *GifExtension);
169 int EGifPutCode(GifFileType *GifFile, int GifCodeSize,
170 const GifByteType *GifCodeBlock);
171 int EGifPutCodeNext(GifFileType *GifFile,
172 const GifByteType *GifCodeBlock);
173
174 /******************************************************************************
175 GIF decoding routines
176 ******************************************************************************/
177
178 /* Main entry points */
179 GifFileType *DGifOpenFileName(const char *GifFileName, int *Error);
180 GifFileType *DGifOpenFileHandle(int GifFileHandle, int *Error);
181 int DGifSlurp(GifFileType * GifFile);
182 GifFileType *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 */
201 int DGifGetScreenDesc(GifFileType *GifFile);
202 int DGifGetRecordType(GifFileType *GifFile, GifRecordType *GifType);
203 int DGifGetImageHeader(GifFileType *GifFile);
204 int DGifGetImageDesc(GifFileType *GifFile);
205 int DGifGetLine(GifFileType *GifFile, GifPixelType *GifLine, int GifLineLen);
206 int DGifGetPixel(GifFileType *GifFile, GifPixelType GifPixel);
207 int DGifGetExtension(GifFileType *GifFile, int *GifExtCode,
208 GifByteType **GifExtension);
209 int DGifGetExtensionNext(GifFileType *GifFile, GifByteType **GifExtension);
210 int DGifGetCode(GifFileType *GifFile, int *GifCodeSize,
211 GifByteType **GifCodeBlock);
212 int DGifGetCodeNext(GifFileType *GifFile, GifByteType **GifCodeBlock);
213 int DGifGetLZCodes(GifFileType *GifFile, int *GifCode);
214 const char *DGifGetGifVersion(GifFileType *GifFile);
215
216
217 /******************************************************************************
218 Color table quantization (deprecated)
219 ******************************************************************************/
220 int GifQuantizeBuffer(unsigned int Width, unsigned int Height,
221 int *ColorMapSize, GifByteType * RedInput,
222 GifByteType * GreenInput, GifByteType * BlueInput,
223 GifByteType * OutputBuffer,
224 GifColorType * OutputColorMap);
225
226 /******************************************************************************
227 Error handling and reporting.
228 ******************************************************************************/
229 extern const char *GifErrorString(int ErrorCode); /* new in 2012 - ESR */
230
231 /*****************************************************************************
232 Everything below this point is new after version 1.2, supporting `slurp
233 mode' for doing I/O in two big belts with all the image-bashing in core.
234 ******************************************************************************/
235
236 /******************************************************************************
237 Color map handling from gif_alloc.c
238 ******************************************************************************/
239
240 extern ColorMapObject *GifMakeMapObject(int ColorCount,
241 const GifColorType *ColorMap);
242 extern void GifFreeMapObject(ColorMapObject *Object);
243 extern ColorMapObject *GifUnionColorMap(const ColorMapObject *ColorIn1,
244 const ColorMapObject *ColorIn2,
245 GifPixelType ColorTransIn2[]);
246 extern int GifBitSize(int n);
247
248 /******************************************************************************
249 Support for the in-core structures allocation (slurp mode).
250 ******************************************************************************/
251
252 extern void GifApplyTranslation(SavedImage *Image, GifPixelType Translation[]);
253 extern int GifAddExtensionBlock(int *ExtensionBlock_Count,
254 ExtensionBlock **ExtensionBlocks,
255 int Function,
256 unsigned int Len, unsigned char ExtData[]);
257 extern void GifFreeExtensions(int *ExtensionBlock_Count,
258 ExtensionBlock **ExtensionBlocks);
259 extern SavedImage *GifMakeSavedImage(GifFileType *GifFile,
260 const SavedImage *CopyFrom);
261 extern void GifFreeSavedImages(GifFileType *GifFile);
262
263 /******************************************************************************
264 5.x functions for GIF89 graphics control blocks
265 ******************************************************************************/
266
267 int DGifExtensionToGCB(const size_t GifExtensionLength,
268 const GifByteType *GifExtension,
269 GraphicsControlBlock *GCB);
270 size_t EGifGCBToExtension(const GraphicsControlBlock *GCB,
271 GifByteType *GifExtension);
272
273 int DGifSavedExtensionToGCB(GifFileType *GifFile,
274 int ImageIndex,
275 GraphicsControlBlock *GCB);
276 int EGifGCBToSavedExtension(const GraphicsControlBlock *GCB,
277 GifFileType *GifFile,
278 int ImageIndex);
279
280 /******************************************************************************
281 The library's internal utility font
282 ******************************************************************************/
283
284 #define GIF_FONT_WIDTH 8
285 #define GIF_FONT_HEIGHT 8
286 extern const unsigned char GifAsciiTable8x8[][GIF_FONT_WIDTH];
287
288 extern void GifDrawText8x8(SavedImage *Image,
289 const int x, const int y,
290 const char *legend, const int color);
291
292 extern void GifDrawBox(SavedImage *Image,
293 const int x, const int y,
294 const int w, const int d, const int color);
295
296 extern void GifDrawRectangle(SavedImage *Image,
297 const int x, const int y,
298 const int w, const int d, const int color);
299
300 extern void GifDrawBoxedText8x8(SavedImage *Image,
301 const int x, const int y,
302 const char *legend,
303 const int border, const int bg, const int fg);
304
305 #ifdef __cplusplus
306 }
307 #endif /* __cplusplus */
308 #endif /* _GIF_LIB_H */
309
310 /* end */