jpeglib.h

ESS3890+SL原代码（1*16内存）

/* Copyright 2000, ESS Technology, Inc.                                 */
/* SCCSID @(#)jpeglib.h	1.2 01/22/02 */

/* Based on DVD/SVCD version 1.8 02/21/01 */

/* $Id$ */

/*
 * $Log$
 */


/*
 * jpeglib.h
 *
 * Copyright (C) 1991-1995, Thomas G. Lane.
 * This file is part of the Independent JPEG Group's software.
 * For conditions of distribution and use, see the accompanying README file.
 *
 * This file defines the application interface for the JPEG library.
 * Most applications using the library need only include this file,
 * and perhaps jerror.h if they want to know the exact error codes.
 */

#ifndef JPEGLIB_H
#define JPEGLIB_H


#include "platform.h"
/*#include "gdi_image.h"*/
#include "gdi_img.h"
/*
 * First we include the configuration files that record how this
 * installation of the JPEG library is set up.  jconfig.h can be
 * generated automatically for many systems.  jmorecfg.h contains
 * manual configuration options that most people need not worry about.
 */

#ifndef JCONFIG_INCLUDED        /* in case jinclude.h already did */
#include "jconfig.h"            /* widely used configuration options */
#endif
#include "jmorecfg.h"           /* seldom changed options */

#ifdef NO_FILE_SYSTEM
#ifndef FILE
#define FILE char
#endif
#endif

#define ROTATE_NONE 		0
#define ROTATE_INVERT		1
#define ROTATE_MIRROR		2
#define ROTATE_TRANSPOSE	3
#define ROTATE_LEFT		4
#define ROTATE_RIGHT		5


/* Version ID for the JPEG library.
 * Might be useful for tests like "#if JPEG_LIB_VERSION >= 60".
 */

#define JPEG_LIB_VERSION  60    /* Version 6 */


/* Various constants determining the sizes of things.
 * All of these are specified by the JPEG standard, so don't change them
 * if you want to be compatible.
 */

#define DCTSIZE             8   /* The basic DCT block is 8x8 samples */
#define DCTSIZE2            64  /* DCTSIZE squared; # of elements in a block */
#define NUM_QUANT_TBLS      4   /* Quantization tables are numbered 0..3 */
#define NUM_HUFF_TBLS       4   /* Huffman tables are numbered 0..3 */
#define NUM_ARITH_TBLS      16  /* Arith-coding tables are numbered 0..15 */
#define MAX_COMPS_IN_SCAN   4   /* JPEG limit on # of components in one scan */
#define MAX_SAMP_FACTOR     4   /* JPEG limit on sampling factors */
/* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard;
 * the PostScript DCT filter can emit files with many more than 10 blocks/MCU.
 * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU
 * to handle it.  We even let you do this from the jconfig.h file.  However,
 * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe
 * sometimes emits noncompliant files doesn't mean you should too.
 */
#define C_MAX_BLOCKS_IN_MCU   10 /* compressor's limit on blocks per MCU */
#ifndef D_MAX_BLOCKS_IN_MCU
#define D_MAX_BLOCKS_IN_MCU   10 /* decompressor's limit on blocks per MCU */
#endif


/* This macro is used to declare a "method", that is, a function pointer.
 * We want to supply prototype parameters if the compiler can cope.
 * Note that the arglist parameter must be parenthesized!
 */

#ifdef HAVE_PROTOTYPES
#define JMETHOD(type,methodname,arglist)  type (*methodname) arglist
#else
#define JMETHOD(type,methodname,arglist)  type (*methodname) ()
#endif


/* Data structures for images (arrays of samples and of DCT coefficients).
 * On 80x86 machines, the image arrays are too big for near pointers,
 * but the pointer arrays can fit in near memory.
 */

typedef JSAMPLE FAR *JSAMPROW;         /* ptr to one image row of pixel samples. */
typedef JSAMPROW *JSAMPARRAY;          /* ptr to some rows (a 2-D sample array) */
typedef JSAMPARRAY *JSAMPIMAGE;        /* a 3-D sample array: top index is color */

#ifdef JPEG_VP_RLA_VERIFY
/* add an extra block of reference data */
/* The 1 is redundant, it was used to test if VP automatically generate 
 * endio at end of 8x8.  The answer is yes.
 */
typedef JCOEF JBLOCK[DCTSIZE2+DCTSIZE2+1];        /* one block of coefficients */
#else
typedef JCOEF JBLOCK[DCTSIZE2];        /* one block of coefficients */
#endif
typedef JBLOCK FAR *JBLOCKROW;         /* pointer to one row of coefficient blocks */
typedef JBLOCKROW *JBLOCKARRAY;        /* a 2-D array of coefficient blocks */
typedef JBLOCKARRAY *JBLOCKIMAGE;      /* a 3-D array of coefficient blocks */

typedef JCOEF FAR *JCOEFPTR;    /* useful in a couple of places */


/* Types for JPEG compression parameters and working tables. */


/* DCT coefficient quantization tables. */

typedef struct {
  /* This field directly represents the contents of a JPEG DQT marker.
   * Note: the values are always given in zigzag order.
   */
  UINT16 quantval[DCTSIZE2];    /* quantization step for each coefficient */
  /* This field is used only during compression.  It's initialized FALSE when
   * the table is created, and set TRUE when it's been output to the file.
   * You could suppress output of a table by setting this to TRUE.
   * (See jpeg_suppress_tables for an example.)
   */
  my_boolean sent_table;                /* TRUE when table has been output */
} JQUANT_TBL;


/* Huffman coding tables. */

typedef struct {
  /* These two fields directly represent the contents of a JPEG DHT marker */
  UINT8 bits[17];               /* bits[k] = # of symbols with codes of */
                                /* length k bits; bits[0] is unused */
  UINT8 huffval[256];           /* The symbols, in order of incr code length */
  /* This field is used only during compression.  It's initialized FALSE when
   * the table is created, and set TRUE when it's been output to the file.
   * You could suppress output of a table by setting this to TRUE.
   * (See jpeg_suppress_tables for an example.)
   */
  my_boolean sent_table;                /* TRUE when table has been output */
} JHUFF_TBL;


/* Basic info about one component (color channel). */

typedef struct {
  /* These values are fixed over the whole image. */
  /* For compression, they must be supplied by parameter setup; */
  /* for decompression, they are read from the SOF marker. */
  int component_id;             /* identifier for this component (0..255) */
  int component_index;          /* its index in SOF or cinfo->comp_info[] */
  int h_samp_factor;            /* horizontal sampling factor (1..4) */
  int v_samp_factor;            /* vertical sampling factor (1..4) */
  int quant_tbl_no;             /* quantization table selector (0..3) */
  /* These values may vary between scans. */
  /* For compression, they must be supplied by parameter setup; */
  /* for decompression, they are read from the SOS marker. */
  /* The decompressor output side may not use these variables. */
  int dc_tbl_no;                /* DC entropy table selector (0..3) */
  int ac_tbl_no;                /* AC entropy table selector (0..3) */
  
  /* Remaining fields should be treated as private by applications. */
  
  /* These values are computed during compression or decompression startup: */
  /* Component's size in DCT blocks.
   * Any dummy blocks added to complete an MCU are not counted; therefore
   * these values do not depend on whether a scan is interleaved or not.
   */
  JDIMENSION width_in_blocks;
  JDIMENSION height_in_blocks;
  /* Size of a DCT block in samples.  Always DCTSIZE for compression.
   * For decompression this is the size of the output from one DCT block,
   * reflecting any scaling we choose to apply during the IDCT step.
   * Values of 1,2,4,8 are likely to be supported.  Note that different
   * components may receive different IDCT scalings.
   */
  int DCT_scaled_size;
  /* The downsampled dimensions are the component's actual, unpadded number
   * of samples at the main buffer (preprocessing/compression interface), thus
   * downsampled_width = ceil(image_width * Hi/Hmax)
   * and similarly for height.  For decompression, IDCT scaling is included, so
   * downsampled_width = ceil(image_width * Hi/Hmax * DCT_scaled_size/DCTSIZE)
   */
  JDIMENSION downsampled_width;  /* actual width in samples */
  JDIMENSION downsampled_height; /* actual height in samples */
  /* This flag is used only for decompression.  In cases where some of the
   * components will be ignored (eg grayscale output from YCbCr image),
   * we can skip most computations for the unused components.
   */
  my_boolean component_needed;  /* do we need the value of this component? */

  /* These values are computed before starting a scan of the component. */
  /* The decompressor output side may not use these variables. */
  int MCU_width;                /* number of blocks per MCU, horizontally */
  int MCU_height;               /* number of blocks per MCU, vertically */
  int MCU_blocks;               /* MCU_width * MCU_height */
  int MCU_sample_width;         /* MCU width in samples, MCU_width*DCT_scaled_size */
  int last_col_width;           /* # of non-dummy blocks across in last MCU */
  int last_row_height;          /* # of non-dummy blocks down in last MCU */

  /* Saved quantization table for component; NULL if none yet saved.
   * See jdinput.c comments about the need for this information.
   * This field is not currently used by the compressor.
   */
  JQUANT_TBL * quant_table;

  /* Private per-component storage for DCT or IDCT subsystem. */
  void * dct_table;

  /* for optimization only */
  /* YUV444, YUV420, yUV422???????*/
  int UV_need_upsample;
} jpeg_component_info;


/* The script for encoding a multiple-scan file is an array of these: */

typedef struct {
  int comps_in_scan;            /* number of components encoded in this scan */
  int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */
  int Ss, Se;                   /* progressive JPEG spectral selection parms */
  int Ah, Al;                   /* progressive JPEG successive approx. parms */
} jpeg_scan_info;


/* Known color spaces. */

typedef enum {
        JCS_UNKNOWN,            /* error/unspecified */
        JCS_GRAYSCALE,          /* monochrome */
        JCS_RGB,                /* red/green/blue */
        JCS_YCbCr,              /* Y/Cb/Cr (also known as YUV) */
        JCS_CMYK,               /* C/M/Y/K */
        JCS_YCCK                /* Y/Cb/Cr/K */
} J_COLOR_SPACE;

/* DCT/IDCT algorithm options. */

typedef enum {
        JDCT_ISLOW,             /* slow but accurate integer algorithm */
        JDCT_IFAST,             /* faster, less accurate integer method */
        JDCT_FLOAT              /* floating-point: accurate, fast on fast HW */
} J_DCT_METHOD;

#ifndef JDCT_DEFAULT            /* may be overridden in jconfig.h */
#define JDCT_DEFAULT  JDCT_ISLOW
#endif
#ifndef JDCT_FASTEST            /* may be overridden in jconfig.h */
#define JDCT_FASTEST  JDCT_IFAST
#endif

/* Dithering options for decompression. */

typedef enum {
        JDITHER_NONE,           /* no dithering */
        JDITHER_ORDERED,        /* simple ordered dither */
        JDITHER_FS              /* Floyd-Steinberg error diffusion dither */
} J_DITHER_MODE;


/* Common fields between JPEG compression and decompression master structs. */

#define jpeg_common_fields \