/*
* File: ximagif.h
* Purpose: GIF Image Class Loader and Writer
*/
/* ==========================================================
* CxImageGIF (c) 07/Aug/2001 Davide Pizzolato - www.xdp.it
* For conditions of distribution and use, see copyright notice in ximage.h
*
* Special thanks to Troels Knakkergaard for new features, enhancements and bugfixes
*
* original CImageGIF and CImageIterator implementation are:
* Copyright: (c) 1995, Alejandro Aguilar Sierra <asierra(at)servidor(dot)unam(dot)mx>
*
* 6/15/97 Randy Spann: Added GIF87a writing support
* R.Spann@ConnRiver.net
*
* DECODE.C - An LZW decoder for GIF
* Copyright (C) 1987, by Steven A. Bennett
* Copyright (C) 1994, C++ version by Alejandro Aguilar Sierra
*
* In accordance with the above, I want to credit Steve Wilhite who wrote
* the code which this is heavily inspired by...
*
* GIF and 'Graphics Interchange Format' are trademarks (tm) of
* Compuserve, Incorporated, an H&R Block Company.
*
* Release Notes: This file contains a decoder routine for GIF images
* which is similar, structurally, to the original routine by Steve Wilhite.
* It is, however, somewhat noticably faster in most cases.
*
* ==========================================================
*/
#if !defined(__ximaGIF_h)
#define __ximaGIF_h
#include "ximage.h"
#if CXIMAGE_SUPPORT_GIF
typedef int16_t code_int;
/* Various error codes used by decoder */
#define OUT_OF_MEMORY -10
#define BAD_CODE_SIZE -20
#define READ_ERROR -1
#define WRITE_ERROR -2
#define OPEN_ERROR -3
#define CREATE_ERROR -4
#define BAD_LINE_WIDTH -5
#define MAX_CODES 4095
#define GIFBUFTAM 16383
#define TRANSPARENCY_CODE 0xF9
//LZW GIF Image compression
#define MAXBITSCODES 12
#define HSIZE 5003 /* 80% occupancy */
#define MAXCODE(n_bits) (((code_int) 1 << (n_bits)) - 1)
#define HashTabOf(i) htab[i]
#define CodeTabOf(i) codetab[i]
class CImageIterator;
class DLL_EXP CxImageGIF: public CxImage
{
#pragma pack(1)
typedef struct tag_gifgce{
uint8_t flags; /*res:3|dispmeth:3|userinputflag:1|transpcolflag:1*/
uint16_t delaytime;
uint8_t transpcolindex;
} struct_gifgce;
typedef struct tag_dscgif{ /* Logic Screen Descriptor */
char header[6]; /* Firma and version */
uint16_t scrwidth;
uint16_t scrheight;
char pflds;
char bcindx;
char pxasrat;
} struct_dscgif;
typedef struct tag_image{ /* Image Descriptor */
uint16_t l;
uint16_t t;
uint16_t w;
uint16_t h;
uint8_t pf;
} struct_image;
typedef struct tag_TabCol{ /* Tabla de colores */
int16_t colres; /* color resolution */
int16_t sogct; /* size of global color table */
rgb_color paleta[256]; /* paleta */
} struct_TabCol;
typedef struct tag_RLE{
int32_t rl_pixel;
int32_t rl_basecode;
int32_t rl_count;
int32_t rl_table_pixel;
int32_t rl_table_max;
int32_t just_cleared;
int32_t out_bits;
int32_t out_bits_init;
int32_t out_count;
int32_t out_bump;
int32_t out_bump_init;
int32_t out_clear;
int32_t out_clear_init;
int32_t max_ocodes;
int32_t code_clear;
int32_t code_eof;
uint32_t obuf;
int32_t obits;
uint8_t oblock[256];
int32_t oblen;
} struct_RLE;
#pragma pack()
public:
CxImageGIF();
~CxImageGIF();
// bool Load(const TCHAR * imageFileName){ return CxImage::Load(imageFileName,CXIMAGE_FORMAT_GIF);}
// bool Save(const TCHAR * imageFileName){ return CxImage::Save(imageFileName,CXIMAGE_FORMAT_GIF);}
bool Decode(CxFile * fp);
bool Decode(FILE *fp) { CxIOFile file(fp); return Decode(&file); }
#if CXIMAGE_SUPPORT_ENCODE
bool Encode(CxFile * fp);
bool Encode(CxFile * fp, CxImage ** pImages, int32_t pagecount, bool bLocalColorMap = false, bool bLocalDispMeth = false);
bool Encode(FILE *fp) { CxIOFile file(fp); return Encode(&file); }
bool Encode(FILE *fp, CxImage ** pImages, int32_t pagecount, bool bLocalColorMap = false)
{ CxIOFile file(fp); return Encode(&file, pImages, pagecount, bLocalColorMap); }
#endif // CXIMAGE_SUPPORT_ENCODE
void SetLoops(int32_t loops);
int32_t GetLoops();
void SetComment(const char* sz_comment_in);
void GetComment(char* sz_comment_out);
protected:
bool DecodeExtension(CxFile *fp);
void EncodeHeader(CxFile *fp);
void EncodeLoopExtension(CxFile *fp);
void EncodeExtension(CxFile *fp);
void EncodeBody(CxFile *fp, bool bLocalColorMap = false);
void EncodeComment(CxFile *fp);
bool EncodeRGB(CxFile *fp);
void GifMix(CxImage & imgsrc2, struct_image & imgdesc);
struct_gifgce gifgce;
int32_t curx, cury;
int32_t CountDown;
uint32_t cur_accum;
int32_t cur_bits;
int32_t interlaced, iypos, istep, iheight, ipass;
int32_t ibf;
int32_t ibfmax;
uint8_t * buf;
// Implementation
int32_t GifNextPixel ();
void Putword (int32_t w, CxFile* fp );
void compressNONE (int32_t init_bits, CxFile* outfile);
void compressLZW (int32_t init_bits, CxFile* outfile);
void output (code_int code );
void cl_hash (int32_t hsize);
void char_out (int32_t c);
void flush_char ();
int16_t init_exp(int16_t size);
int16_t get_next_code(CxFile*);
int16_t decoder(CxFile*, CImageIterator* iter, int16_t linewidth, int32_t &bad_code_count);
int32_t get_byte(CxFile*);
int32_t out_line(CImageIterator* iter, uint8_t *pixels, int32_t linelen);
int32_t get_num_frames(CxFile *f,struct_TabCol* TabColSrc,struct_dscgif* dscgif);
int32_t seek_next_image(CxFile* fp, int32_t position);
int16_t curr_size; /* The current code size */
int16_t clear; /* Value for a clear code */
int16_t ending; /* Value for a ending code */
int16_t newcodes; /* First available code */
int16_t top_slot; /* Highest code for current size */
int16_t slot; /* Last read code */
/* The following static variables are used
* for seperating out codes */
int16_t navail_bytes; /* # bytes left in block */
int16_t nbits_left; /* # bits left in current uint8_t */
uint8_t b1; /* Current uint8_t */
uint8_t * byte_buff; /* Current block */
uint8_t *pbytes; /* Pointer to next uint8_t in block */
/* The reason we have these seperated like this instead of using
* a structure like the original Wilhite code did, is because this
* stuff generally produces significantly faster code when compiled...
* This code is full of similar speedups... (For a good book on writing
* C for speed or for space optomisation, see Efficient C by Tom Plum,
* published by Plum-Hall Associates...)
*/
uint8_t * stack; /* Stack for storing pixels */
uint8_t * suffix; /* Suffix table */
uint16_t * prefix; /* Prefix linked list */
//LZW GIF Image compression routines
int32_t * htab;
uint16_t * codetab;
int32_t n_bits; /* number of bits/code */
code_int maxcode; /* maximum code, given n_bits */
code_int free_ent; /* first unused entry */
int32_t clear_flg;
int32_t g_init_bits;
CxFile* g_outfile;
int32_t ClearCode;
int32_t EOFCode;
int32_t a_count;
char * accum;
char * m_comment;
int32_t m_loops;
//RLE compression routines
void compressRLE( int32_t init_bits, CxFile* outfile);
void rle_clear(struct_RLE* rle);
void rle_flush(struct_RLE* rle);
void rle_flush_withtable(int32_t count, struct_RLE* rle);
void rle_flush_clearorrep(int32_t count, struct_RLE* rle);
void rle_flush_fromclear(int32_t count,struct_RLE* rle);
void rle_output_plain(int32_t c,struct_RLE* rle);
void rle_reset_out_clear(struct_RLE* rle);
uint32_t rle_compute_triangle_count(uint32_t count, uint32_t nrepcodes);
uint32_t rle_isqrt(uint32_t x);
void rle_write_block(struct_RLE* rle);
void rle_block_out(uint8_t c, struct_RLE* rle);
void rle_block_flush(struct_RLE* rle);
void rle_output(int32_t val, struct_RLE* rle);
void rle_output_flush(struct_RLE* rle);
};
#endif
#endif
