60 lines
2.4 KiB
C
60 lines
2.4 KiB
C
|
/****************************************************************************
|
||
|
|
|
||
|
|
gif_lib_private.h - internal giflib routines and structures
|
||
|
|
|
||
|
|
****************************************************************************/
|
||
|
|
|
||
|
|
#ifndef _GIF_LIB_PRIVATE_H
|
||
|
|
#define _GIF_LIB_PRIVATE_H
|
||
|
|
|
||
|
|
#include "gif_lib.h"
|
||
|
|
#include "gif_hash.h"
|
||
|
|
|
||
|
|
#define EXTENSION_INTRODUCER 0x21
|
||
|
|
#define DESCRIPTOR_INTRODUCER 0x2c
|
||
|
|
#define TERMINATOR_INTRODUCER 0x3b
|
||
|
|
|
||
|
|
#define LZ_MAX_CODE 4095 /* Biggest code possible in 12 bits. */
|
||
|
|
#define LZ_BITS 12
|
||
|
|
|
||
|
|
#define FLUSH_OUTPUT 4096 /* Impossible code, to signal flush. */
|
||
|
|
#define FIRST_CODE 4097 /* Impossible code, to signal first. */
|
||
|
|
#define NO_SUCH_CODE 4098 /* Impossible code, to signal empty. */
|
||
|
|
|
||
|
|
#define FILE_STATE_WRITE 0x01
|
||
|
|
#define FILE_STATE_SCREEN 0x02
|
||
|
|
#define FILE_STATE_IMAGE 0x04
|
||
|
|
#define FILE_STATE_READ 0x08
|
||
|
|
|
||
|
|
#define IS_READABLE(Private) (Private->FileState & FILE_STATE_READ)
|
||
|
|
#define IS_WRITEABLE(Private) (Private->FileState & FILE_STATE_WRITE)
|
||
|
|
|
||
|
|
typedef struct GifFilePrivateType {
|
||
|
|
GifWord FileState, FileHandle, /* Where all this data goes to! */
|
||
|
|
BitsPerPixel, /* Bits per pixel (Codes uses at least this + 1). */
|
||
|
|
ClearCode, /* The CLEAR LZ code. */
|
||
|
|
EOFCode, /* The EOF LZ code. */
|
||
|
|
RunningCode, /* The next code algorithm can generate. */
|
||
|
|
RunningBits, /* The number of bits required to represent RunningCode. */
|
||
|
|
MaxCode1, /* 1 bigger than max. possible code, in RunningBits bits. */
|
||
|
|
LastCode, /* The code before the current code. */
|
||
|
|
CrntCode, /* Current algorithm code. */
|
||
|
|
StackPtr, /* For character stack (see below). */
|
||
|
|
CrntShiftState; /* Number of bits in CrntShiftDWord. */
|
||
|
|
unsigned long CrntShiftDWord; /* For bytes decomposition into codes. */
|
||
|
|
unsigned long PixelCount; /* Number of pixels in image. */
|
||
|
|
int File; /* File as stream. (converted to int in rb) */
|
||
|
|
InputFunc Read; /* function to read gif input (TVT) */
|
||
|
|
OutputFunc Write; /* function to write gif output (MRB) */
|
||
|
|
GifByteType Buf[256]; /* Compressed input is buffered here. */
|
||
|
|
GifByteType Stack[LZ_MAX_CODE]; /* Decoded pixels are stacked here. */
|
||
|
|
GifByteType Suffix[LZ_MAX_CODE + 1]; /* So we can trace the codes. */
|
||
|
|
GifPrefixType Prefix[LZ_MAX_CODE + 1];
|
||
|
|
GifHashTableType *HashTable;
|
||
|
|
bool gif89;
|
||
|
|
} GifFilePrivateType;
|
||
|
|
|
||
|
|
#endif /* _GIF_LIB_PRIVATE_H */
|
||
|
|
|
||
|
|
/* end */
|