gif_lib.h

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/******************************************************************************
* In order to make life a little bit easier when using the GIF file format,   *
* this library was written, and which does all the dirty work...              *
*                                                                             *
*                                        Written by Gershon Elber,  Jun. 1989 *
*                                        Hacks by Eric S. Raymond,  Sep. 1992 *
*******************************************************************************
* History:                                                                    *
* 14 Jun 89 - Version 1.0 by Gershon Elber.                                   *
*  3 Sep 90 - Version 1.1 by Gershon Elber (Support for Gif89, Unique names)  *
* 15 Sep 90 - Version 2.0 by Eric S. Raymond (Changes to suoport GIF slurp)   *
* 26 Jun 96 - Version 3.0 by Eric S. Raymond (Full GIF89 support)             * 
* 17 Dec 98 - Version 4.0 by Toshio Kuratomi (Fix extension writing code)     *
******************************************************************************/

#ifndef _GIF_LIB_H
#define _GIF_LIB_H

#define GIF_LIB_VERSION " Version 4.0, "

#define GIF_ERROR       0
#define GIF_OK          1

#ifndef TRUE
#define TRUE            1
#define FALSE           0
#endif

#ifndef NULL
#define NULL            0
#endif /* NULL */

#define GIF_STAMP "GIFVER"          /* First chars in file - GIF stamp.  */
#define GIF_STAMP_LEN sizeof(GIF_STAMP) - 1
#define GIF_VERSION_POS 3           /* Version first character in stamp. */
#define GIF87_STAMP     "GIF87a"        /* First chars in file - GIF stamp.  */
#define GIF89_STAMP     "GIF89a"        /* First chars in file - GIF stamp.  */

#define GIF_FILE_BUFFER_SIZE 16384  /* Files uses bigger buffers than usual. */

typedef int             GifBooleanType;
typedef unsigned char   GifPixelType;
typedef unsigned char * GifRowType;
typedef unsigned char   GifByteType;

#define GIF_MESSAGE(Msg) fprintf(stderr, "\n%s: %s\n", PROGRAM_NAME, Msg)
#define GIF_EXIT(Msg)   { GIF_MESSAGE(Msg); exit(-3); }

#ifdef SYSV
#define VoidPtr char *
#else
#define VoidPtr void *
#endif /* SYSV */

typedef struct GifColorType {
    GifByteType Red, Green, Blue;
} GifColorType;

typedef struct ColorMapObject
{
    int ColorCount;
    int BitsPerPixel;
    GifColorType *Colors;               /* on malloc(3) heap */
}
ColorMapObject;

typedef struct GifImageDesc {
    int Left, Top, Width, Height,       /* Current image dimensions. */
        Interlace;                      /* Sequential/Interlaced lines. */
    ColorMapObject *ColorMap;           /* The local color map */
} GifImageDesc;

typedef struct GifFileType {
    int SWidth, SHeight,                /* Screen dimensions. */
        SColorResolution,               /* How many colors can we generate? */
        SBackGroundColor;               /* I hope you understand this one... */
    ColorMapObject *SColorMap;          /* NULL if not exists. */
    int ImageCount;                     /* Number of current image */
    GifImageDesc Image;                 /* Block describing current image */
    struct SavedImage *SavedImages;     /* Use this to accumulate file state */
    VoidPtr UserData;           /* hook to attach user data (TVT) */
    VoidPtr Private;                    /* Don't mess with this! */
} GifFileType;

typedef enum {
    UNDEFINED_RECORD_TYPE,
    SCREEN_DESC_RECORD_TYPE,
    IMAGE_DESC_RECORD_TYPE,             /* Begin with ',' */
    EXTENSION_RECORD_TYPE,              /* Begin with '!' */
    TERMINATE_RECORD_TYPE               /* Begin with ';' */
} GifRecordType;

/* DumpScreen2Gif routine constants identify type of window/screen to dump.  */
/* Note all values below 1000 are reserved for the IBMPC different display   */
/* devices (it has many!) and are compatible with the numbering TC2.0        */
/* (Turbo C 2.0 compiler for IBM PC) gives to these devices.                 */
typedef enum {
    GIF_DUMP_SGI_WINDOW = 1000,
    GIF_DUMP_X_WINDOW = 1001
} GifScreenDumpType;

/* func type to read gif data from arbitrary sources (TVT) */
typedef int (*InputFunc)(GifFileType*,GifByteType*,int);

/* func type to write gif data ro arbitrary targets.
 * Returns count of bytes written. (MRB)
 */
typedef int (*OutputFunc)(GifFileType *, const GifByteType *, int);
/******************************************************************************
*  GIF89 extension function codes                                             *
******************************************************************************/

#define COMMENT_EXT_FUNC_CODE           0xfe    /* comment */
#define GRAPHICS_EXT_FUNC_CODE          0xf9    /* graphics control */
#define PLAINTEXT_EXT_FUNC_CODE         0x01    /* plaintext */
#define APPLICATION_EXT_FUNC_CODE       0xff    /* application block */

/******************************************************************************
* O.K., here are the routines one can access in order to encode GIF file:     *
* (GIF_LIB file EGIF_LIB.C).                                                  *
******************************************************************************/

GifFileType *EGifOpenFileName(const char *GifFileName, int GifTestExistance);
GifFileType *EGifOpenFileHandle(int GifFileHandle);
GifFileType *EgifOpen(void *userPtr, OutputFunc writeFunc);
int EGifSpew(GifFileType *GifFile);
void EGifSetGifVersion(const char *Version);
int EGifPutScreenDesc(GifFileType *GifFile,
        int GifWidth, int GifHeight, int GifColorRes, int GifBackGround,
        const ColorMapObject *GifColorMap);
int EGifPutImageDesc(GifFileType *GifFile,
        int GifLeft, int GifTop, int Width, int GifHeight, int GifInterlace,
        const ColorMapObject *GifColorMap);
int EGifPutLine(GifFileType *GifFile, GifPixelType *GifLine, int GifLineLen);
int EGifPutPixel(GifFileType *GifFile, GifPixelType GifPixel);
int EGifPutComment(GifFileType *GifFile, const char *GifComment);
int EGifPutExtensionFirst(GifFileType *GifFile, int GifExtCode, int GifExtLen,
                           const VoidPtr GifExtension);
int EGifPutExtensionNext(GifFileType *GifFile, int GifExtCode, int GifExtLen,
                           const VoidPtr GifExtension);
int EGifPutExtensionLast(GifFileType *GifFile, int GifExtCode, int GifExtLen,
                           const VoidPtr GifExtension);
int EGifPutExtension(GifFileType *GifFile, int GifExtCode, int GifExtLen,
                                                        const VoidPtr GifExtension);
int EGifPutCode(GifFileType *GifFile, int GifCodeSize,
                                          const GifByteType *GifCodeBlock);
int EGifPutCodeNext(GifFileType *GifFile, const GifByteType *GifCodeBlock);
int EGifCloseFile(GifFileType *GifFile);

#define E_GIF_ERR_OPEN_FAILED   1               /* And EGif possible errors. */
#define E_GIF_ERR_WRITE_FAILED  2
#define E_GIF_ERR_HAS_SCRN_DSCR 3
#define E_GIF_ERR_HAS_IMAG_DSCR 4
#define E_GIF_ERR_NO_COLOR_MAP  5
#define E_GIF_ERR_DATA_TOO_BIG  6
#define E_GIF_ERR_NOT_ENOUGH_MEM 7
#define E_GIF_ERR_DISK_IS_FULL  8
#define E_GIF_ERR_CLOSE_FAILED  9
#define E_GIF_ERR_NOT_WRITEABLE 10

/******************************************************************************
* O.K., here are the routines one can access in order to decode GIF file:     *
* (GIF_LIB file DGIF_LIB.C).                                                  *
******************************************************************************/

GifFileType *DGifOpenFileName(const char *GifFileName);
GifFileType *DGifOpenFileHandle(int GifFileHandle);
GifFileType *DGifOpen( void* userPtr, InputFunc readFunc );  /* new one (TVT) */
int DGifSlurp(GifFileType *GifFile);
int DGifGetScreenDesc(GifFileType *GifFile);
int DGifGetRecordType(GifFileType *GifFile, GifRecordType *GifType);
int DGifGetImageDesc(GifFileType *GifFile);
int DGifGetLine(GifFileType *GifFile, GifPixelType *GifLine, int GifLineLen);
int DGifGetPixel(GifFileType *GifFile, GifPixelType GifPixel);
int DGifGetComment(GifFileType *GifFile, char *GifComment);
int DGifGetExtension(GifFileType *GifFile, int *GifExtCode,
                                                GifByteType **GifExtension);
int DGifGetExtensionNext(GifFileType *GifFile, GifByteType **GifExtension);
int DGifGetCode(GifFileType *GifFile, int *GifCodeSize,
                                                GifByteType **GifCodeBlock);
int DGifGetCodeNext(GifFileType *GifFile, GifByteType **GifCodeBlock);
int DGifGetLZCodes(GifFileType *GifFile, int *GifCode);
int DGifCloseFile(GifFileType *GifFile);

#define D_GIF_ERR_OPEN_FAILED   101             /* And DGif possible errors. */
#define D_GIF_ERR_READ_FAILED   102
#define D_GIF_ERR_NOT_GIF_FILE  103
#define D_GIF_ERR_NO_SCRN_DSCR  104
#define D_GIF_ERR_NO_IMAG_DSCR  105
#define D_GIF_ERR_NO_COLOR_MAP  106
#define D_GIF_ERR_WRONG_RECORD  107
#define D_GIF_ERR_DATA_TOO_BIG  108
#define D_GIF_ERR_NOT_ENOUGH_MEM 109
#define D_GIF_ERR_CLOSE_FAILED  110
#define D_GIF_ERR_NOT_READABLE  111
#define D_GIF_ERR_IMAGE_DEFECT  112
#define D_GIF_ERR_EOF_TOO_SOON  113

/******************************************************************************
* O.K., here are the routines from GIF_LIB file QUANTIZE.C.                   *
******************************************************************************/
int QuantizeBuffer(unsigned int Width, unsigned int Height, int *ColorMapSize,
        GifByteType *RedInput, GifByteType *GreenInput, GifByteType *BlueInput,
        GifByteType *OutputBuffer, GifColorType *OutputColorMap);


/******************************************************************************
* O.K., here are the routines from GIF_LIB file QPRINTF.C.                    *
******************************************************************************/
extern int GifQuietPrint;

#ifdef HAVE_VARARGS_H
extern void GifQprintf();
#else
extern void GifQprintf(char *Format, ...);
#endif /* HAVE_VARARGS_H */

/******************************************************************************
* O.K., here are the routines from GIF_LIB file GIF_ERR.C.                    *
******************************************************************************/
extern void PrintGifError(void);
extern int GifLastError(void);

/******************************************************************************
* O.K., here are the routines from GIF_LIB file DEV2GIF.C.                    *
******************************************************************************/
extern int DumpScreen2Gif(const char *FileName,
                          int ReqGraphDriver,
                          int ReqGraphMode1,
                          int ReqGraphMode2,
                          int ReqGraphMode3);

/*****************************************************************************
 *
 * Everything below this point is new after version 1.2, supporting `slurp
 * mode' for doing I/O in two big belts with all the image-bashing in core.
 *
 *****************************************************************************/

/******************************************************************************
* Color Map handling from ALLOCGIF.C                                          *
******************************************************************************/

extern ColorMapObject *MakeMapObject(int ColorCount, const GifColorType *ColorMap);
extern void FreeMapObject(ColorMapObject *Object);
extern ColorMapObject *UnionColorMap(
                                const ColorMapObject *ColorIn1,
                                const ColorMapObject *ColorIn2,
                                GifPixelType ColorTransIn2[]);
extern int BitSize(int n);

/******************************************************************************
* Support for the in-core structures allocation (slurp mode).                 *
******************************************************************************/

/* This is the in-core version of an extension record */
typedef struct {
    int         ByteCount;
    char        *Bytes;         /* on malloc(3) heap */
    int Function;       /* Holds the type of the Extension block. */
} ExtensionBlock;

/* This holds an image header, its unpacked raster bits, and extensions */
typedef struct SavedImage {
    GifImageDesc        ImageDesc;

    char                *RasterBits;            /* on malloc(3) heap */

    int                 Function; /* DEPRECATED: Use ExtensionBlocks[x].Function
                           * instead */
    int                 ExtensionBlockCount;
    ExtensionBlock      *ExtensionBlocks;       /* on malloc(3) heap */
} SavedImage;

extern void ApplyTranslation(SavedImage *Image, GifPixelType Translation[]);

extern void MakeExtension(SavedImage *New, int Function);
extern int AddExtensionBlock(SavedImage *New, int Len, char ExtData[]);
extern void FreeExtension(SavedImage *Image);

extern SavedImage *MakeSavedImage(GifFileType *GifFile, const SavedImage *CopyFrom);
extern void FreeSavedImages(GifFileType *GifFile);

/******************************************************************************
* The library's internal utility font                                         *
******************************************************************************/

#define GIF_FONT_WIDTH  8
#define GIF_FONT_HEIGHT 8
extern unsigned char AsciiTable[][GIF_FONT_WIDTH];

extern void DrawText(SavedImage *Image,
                     const int x, const int y,
                     const char *legend,
                     const int color);

extern void DrawBox(SavedImage *Image,
                     const int x, const int y,
                     const int w, const int d,
                     const int color);

void DrawRectangle(SavedImage *Image,
                     const int x, const int y,
                     const int w, const int d,
                     const int color);

extern void DrawBoxedText(SavedImage *Image,
                     const int x, const int y,
                     const char *legend,
                     const int border,
                     const int bg,
                     const int fg);

#endif /* _GIF_LIB_H */

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