wrsprite.h

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/* JPEG decoder 16bit output code
 * Copyright (C) ANT Limited 1999 -- All Rights Reserved -- Confidential
 * $Header: /cvs/repos/src/webimage/dll_jpeg/layers/wrsprite.h,v 1.1.4.2 2003/09/12 09:35:37 simonp Exp $
 */

#ifndef included_wrsprite16_h
#define included_wrsprite16_h

#if LAYERS_STDIO
/*
 * The modules that use fread() and fwrite() always invoke them through
 * these macros.  On some systems you may need to twiddle the argument casts.
 * CAUTION: argument order is different from underlying functions!
 */

#define JFREAD(file,buf,sizeofbuf)  \
  ((size_t) fread((void *) (buf), (size_t) 1, (size_t) (sizeofbuf), (file)))
#define JFWRITE(file,buf,sizeofbuf)  \
  ((size_t) fwrite((const void *) (buf), (size_t) 1, (size_t) (sizeofbuf), (file)))
#else
#define JFREAD(file,buf,sizeofbuf)  0
#define JFWRITE(file,buf,sizeofbuf)  0
#endif

#define SIZEOF(object)	((size_t) sizeof(object))

/*
 * Object interface for djpeg's output file encoding modules
 */

typedef struct djpeg_dest_struct * djpeg_dest_ptr;

struct djpeg_dest_struct {
  /* start_output is called after jpeg_start_decompress finishes.
   * The color map will be ready at this time, if one is needed.
   */
  JMETHOD(void, start_output, (j_decompress_ptr cinfo,
			       djpeg_dest_ptr dinfo));
  /* Emit the specified number of pixel rows from the buffer. */
  JMETHOD(void, put_pixel_rows, (j_decompress_ptr cinfo,
				 djpeg_dest_ptr dinfo,
				 JDIMENSION rows_supplied));
  /* Finish up at the end of the image. */
  JMETHOD(void, finish_output, (j_decompress_ptr cinfo,
				djpeg_dest_ptr dinfo));

  /* Target file spec; filled in by djpeg.c after object is created. */
  FILE * output_file;

  /* Output pixel-row buffer.  Created by module init or start_output.
   * Width is cinfo->output_width * cinfo->output_components;
   * height is buffer_height.
   */
  JSAMPARRAY buffer;
  JDIMENSION buffer_height;
};


/* Private version of data destination object */

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

  char *iobuffer;		/* fwrite's I/O buffer */
  size_t buffer_width;		/* width of I/O buffer */
  JDIMENSION samples_per_row;	/* JSAMPLEs per output row */
  void *outfile;		/* target stream */
  putdst_func putdst;         	/* Destination stream function */
  getdst_func getdst;           /* Destination readback function */
  seekdst_func seekdst;         /* Destination seek function */
  BOOL use_16bpp;               /* 16bpp output (rather than 32bpp) */
  BOOL yuv_out;                 /* 4:2:2 YUV out */
  unsigned int image_offset;    /* offset of the image data in the file */
  webimage_rotate rotate;       /* the rotation to apply */
    unsigned int stride;        /* stride in the data in bytes */
} sprite_dest_struct;

typedef sprite_dest_struct *sprite_dest_ptr;

#define jinit_write_sprite	jIWrSprite

djpeg_dest_ptr jinit_write_sprite JPP((j_decompress_ptr cinfo, void *userdst, void *putdst, void *seekdst, void *getdst, BOOL use_16bpp, BOOL yuv_out, int rotate));

/* routines used in driver code only */
void put_pixel16bpp_rows( j_decompress_ptr cinfo,
                          djpeg_dest_ptr dinfo,
                          JDIMENSION rows_supplied );

#endif

/* eof wrsprite.h */