gif_dither.h

ucOS 模拟环境

#ifndef _GIFDITHER_H_
#define _GIFDITHER_H_


struct jpeg_color_quantizer { long dummy; };
#define ODITHER_SIZE  16	/* dimension of dither matrix */
/* NB: if ODITHER_SIZE is not a power of 2, ODITHER_MASK uses will break */
#define ODITHER_CELLS (ODITHER_SIZE*ODITHER_SIZE)	/* # cells in matrix */
#define ODITHER_MASK  (ODITHER_SIZE-1) /* mask for wrapping around counters*/
typedef int ODITHER_MATRIX[ODITHER_SIZE][ODITHER_SIZE];
typedef int (*ODITHER_MATRIX_PTR)[ODITHER_SIZE];

#define BITS_IN_JSAMPLE  8	/* use 8 or 12 */

#if BITS_IN_JSAMPLE == 8
typedef INT16 FSERROR;		/* 16 bits should be enough */
typedef int LOCFSERROR;		/* use 'int' for calculation temps */
#else
typedef INT32 FSERROR;		/* may need more than 16 bits */
typedef INT32 LOCFSERROR;	/* be sure calculation temps are big enough */
#endif

typedef FSERROR FAR *FSERRPTR;	/* pointer to error array (in FAR storage!) */


/* Private subobject */

#define MAX_Q_COMPS 4		/* max components I can handle */

typedef struct {
  struct jpeg_color_quantizer pub; /* public fields */

  /* Initially allocated colormap is saved here */
  uchar** sv_colormap;	/* The color map as a 2-D pixel array */
  int sv_actual;		/* number of entries in use */

  uchar* colorindex[3] ;	/* Precomputed mapping for speed */
  /* colorindex[i][j] = index of color closest to pixel value j in component i,
   * premultiplied as described above.  Since colormap indexes must fit into
   * JSAMPLEs, the entries of this array will too.
   */
  boolean is_padded;		/* is the colorindex padded for odither? */

  int Ncolors[MAX_Q_COMPS];	/* # of values alloced to each component */

  /* Variables for ordered dithering */
  int row_index;		/* cur row's vertical index in dither matrix */
  ODITHER_MATRIX_PTR odither[MAX_Q_COMPS]; /* one dither array per component */

  /* Variables for Floyd-Steinberg dithering */
  FSERRPTR fserrors[MAX_Q_COMPS]; /* accumulated errors */
  boolean on_odd_row;		/* flag to remember which row we are on */
} my_cquantizer;


typedef my_cquantizer * my_cquantize_ptr;
Bool  Gif_init_1pass_quantizer (decompress_info_ptr  cinfo);
Bool gif_start_pass_1_quant (decompress_info_ptr cinfo, uint rows, uchar* input_buf,uchar* out_buf);
Bool gif_index_to_map(decompress_info_ptr cinfo,uchar* ouput_buf);
Bool gif_rgb_order(decompress_info_ptr cinfo,uchar* output_buf);
Bool gif_alloc_fs_workspace (decompress_info_ptr cinfo);
Bool gif_prepare_range_limit_table (decompress_info_ptr cinfo);

#endif