jutils.cpp File Reference

#include "jinclude.h"
#include "jpeglib.h"

Include dependency graph for jutils.cpp:

Macros
#define	JPEG_INTERNALS
#define	FMEMCOPY(dest, src, size)   MEMCOPY(dest,src,size)
#define	FMEMZERO(target, size)   MEMZERO(target,size)

Functions
long	jdiv_round_up (long a, long b)
long	jround_up (long a, long b)
void	jcopy_sample_rows (JSAMPARRAY input_array, int source_row, JSAMPARRAY output_array, int dest_row, int num_rows, JDIMENSION num_cols)
void	jcopy_block_row (JBLOCKROW input_row, JBLOCKROW output_row, JDIMENSION num_blocks)
void	jzero_far (void *target, size_t bytestozero)

Variables
const int	jpeg_natural_order [64+16]

Macro Definition Documentation

#define JPEG_INTERNALS

#define FMEMCOPY	(		dest,
			src,
			size
	)		MEMCOPY(dest,src,size)

#define FMEMZERO	(		target,
			size
	)		MEMZERO(target,size)

Function Documentation

long jdiv_round_up	(	long	a,
		long	b
	)

{
  return (a + b - 1L) / b;
}

long jround_up	(	long	a,
		long	b
	)

{
  a += b - 1L;
  return a - (a % b);
}

void jcopy_sample_rows	(	JSAMPARRAY	input_array,
		int	source_row,
		JSAMPARRAY	output_array,
		int	dest_row,
		int	num_rows,
		JDIMENSION	num_cols
	)

{
  register JSAMPROW inptr, outptr;
#ifdef FMEMCOPY
  register size_t count = (size_t) (num_cols * SIZEOF(JSAMPLE));
#else
  register JDIMENSION count;
#endif
  register int row;

  input_array += source_row;
  output_array += dest_row;

  for (row = num_rows; row > 0; row--) {
    inptr = *input_array++;
    outptr = *output_array++;
#ifdef FMEMCOPY
    FMEMCOPY(outptr, inptr, count);
#else
    for (count = num_cols; count > 0; count--)
      *outptr++ = *inptr++; /* needn't bother with GETJSAMPLE() here */
#endif
  }
}

void jcopy_block_row	(	JBLOCKROW	input_row,
		JBLOCKROW	output_row,
		JDIMENSION	num_blocks
	)

{
#ifdef FMEMCOPY
  FMEMCOPY(output_row, input_row, num_blocks * (DCTSIZE2 * SIZEOF(JCOEF)));
#else
  register JCOEFPTR inptr, outptr;
  register long count;

  inptr = (JCOEFPTR) input_row;
  outptr = (JCOEFPTR) output_row;
  for (count = (long) num_blocks * DCTSIZE2; count > 0; count--) {
    *outptr++ = *inptr++;
  }
#endif
}

void jzero_far	(	void *	target,
		size_t	bytestozero
	)

{
#ifdef FMEMZERO
  FMEMZERO(target, bytestozero);
#else
  register char FAR * ptr = (char FAR *) target;
  register size_t count;

  for (count = bytestozero; count > 0; count--) {
    *ptr++ = 0;
  }
#endif
}

Variable Documentation

const int jpeg_natural_order[64+16]

Initial value:

= {
  0,  1,  8, 16,  9,  2,  3, 10,
 17, 24, 32, 25, 18, 11,  4,  5,
 12, 19, 26, 33, 40, 48, 41, 34,
 27, 20, 13,  6,  7, 14, 21, 28,
 35, 42, 49, 56, 57, 50, 43, 36,
 29, 22, 15, 23, 30, 37, 44, 51,
 58, 59, 52, 45, 38, 31, 39, 46,
 53, 60, 61, 54, 47, 55, 62, 63,
 63, 63, 63, 63, 63, 63, 63, 63, 
 63, 63, 63, 63, 63, 63, 63, 63
}