jdmerge.c

jpeg编解码器

/*
 * jdmerge.c
 *
 * Copyright (C) 1994-1996, 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 contains code for merged upsampling/color conversion.
 *
 * This file combines functions from jdsample.c and jdcolor.c;
 * read those files first to understand what's going on.
 *
 * When the chroma components are to be upsampled by simple replication
 * (ie, box filtering), we can save some work in color conversion by
 * calculating all the output pixels corresponding to a pair of chroma
 * samples at one time.  In the conversion equations
 *	R = Y           + K1 * Cr
 *	G = Y + K2 * Cb + K3 * Cr
 *	B = Y + K4 * Cb
 * only the Y term varies among the group of pixels corresponding to a pair
 * of chroma samples, so the rest of the terms can be calculated just once.
 * At typical sampling ratios, this eliminates half or three-quarters of the
 * multiplications needed for color conversion.
 *
 * This file currently provides implementations for the following cases:
 *	YCbCr => RGB color conversion only.
 *	Sampling ratios of 2h1v or 2h2v.
 *	No scaling needed at upsample time.
 *	Corner-aligned (non-CCIR601) sampling alignment.
 * Other special cases could be added, but in most applications these are
 * the only common cases.  (For uncommon cases we fall back on the more
 * general code in jdsample.c and jdcolor.c.)
 */

#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"

#ifdef UPSAMPLE_MERGING_SUPPORTED

#if defined(HAVE_MMX_INTEL_MNEMONICS) || defined(HAVE_MMX_ATT_MNEMONICS)
#define __int64 unsigned long long
  __int64 const1 = 0x59BA0000D24B59BALL; // Cr_r Cr_b Cr_g Cr_r
  __int64 const2 = 0x00007168E9FA0000LL; // Cb-r Cb_b Cb_g Cb_r
  __int64 const5 = 0x0000D24B59BA0000LL; // Cr_b Cr_g Cr_r Cr_b
  __int64 const6 = 0x7168E9FA00007168LL; // Cb_b Cb_g Cb_r Cb_b

  // constants for factors (One_Half/fix(x)) << 2

  __int64 const05 = 0x0001000000000001LL; // Cr_r Cr_b Cr_g Cr_r
  __int64 const15 = 0x00000001FFFA0000LL; // Cb-r Cb_b Cb_g Cb_r
  __int64 const45 = 0x0000000000010000LL; // Cr_b Cr_g Cr_r Cr_b
  __int64 const55 = 0x0001FFFA00000001LL; // Cb_b Cb_g Cb_r Cb_b

  // added for MMX
  __int64 const128 = 0x0080008000800080LL;
  __int64 empty    = 0x0000000000000000LL;
  __int64 davemask = 0x0000FFFFFFFF0000LL;
  ////////////////////////////////
#endif

/* Private subobject */

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

  /* Pointer to routine to do actual upsampling/conversion of one row group */
  JMETHOD(void, upmethod, (j_decompress_ptr cinfo,
			   JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr,
			   JSAMPARRAY output_buf));

  /* Private state for YCC->RGB conversion */
  int * Cr_r_tab;		/* => table for Cr to R conversion */
  int * Cb_b_tab;		/* => table for Cb to B conversion */
  INT32 * Cr_g_tab;		/* => table for Cr to G conversion */
  INT32 * Cb_g_tab;		/* => table for Cb to G conversion */

  /* For 2:1 vertical sampling, we produce two output rows at a time.
   * We need a "spare" row buffer to hold the second output row if the
   * application provides just a one-row buffer; we also use the spare
   * to discard the dummy last row if the image height is odd.
   */
  JSAMPROW spare_row;
  boolean spare_full;		/* T if spare buffer is occupied */

  JDIMENSION out_row_width;	/* samples per output row */
  JDIMENSION rows_to_go;	/* counts rows remaining in image */
} my_upsampler;

typedef my_upsampler * my_upsample_ptr;

#define SCALEBITS	16	/* speediest right-shift on some machines */
#define ONE_HALF	((INT32) 1 << (SCALEBITS-1))
#define FIX(x)		((INT32) ((x) * (1L<<SCALEBITS) + 0.5))


/*
 * Initialize tables for YCC->RGB colorspace conversion.
 * This is taken directly from jdcolor.c; see that file for more info.
 */

LOCAL(void)
build_ycc_rgb_table (j_decompress_ptr cinfo)
{
  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
  int i;
  INT32 x;
  SHIFT_TEMPS

  upsample->Cr_r_tab = (int *)
    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
				(MAXJSAMPLE+1) * SIZEOF(int));
  upsample->Cb_b_tab = (int *)
    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
				(MAXJSAMPLE+1) * SIZEOF(int));
  upsample->Cr_g_tab = (INT32 *)
    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
				(MAXJSAMPLE+1) * SIZEOF(INT32));
  upsample->Cb_g_tab = (INT32 *)
    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
				(MAXJSAMPLE+1) * SIZEOF(INT32));

  for (i = 0, x = -CENTERJSAMPLE; i <= MAXJSAMPLE; i++, x++) {
    /* i is the actual input pixel value, in the range 0..MAXJSAMPLE */
    /* The Cb or Cr value we are thinking of is x = i - CENTERJSAMPLE */
    /* Cr=>R value is nearest int to 1.40200 * x */
    upsample->Cr_r_tab[i] = (int)
		    RIGHT_SHIFT(FIX(1.40200) * x + ONE_HALF, SCALEBITS);
    /* Cb=>B value is nearest int to 1.77200 * x */
    upsample->Cb_b_tab[i] = (int)
		    RIGHT_SHIFT(FIX(1.77200) * x + ONE_HALF, SCALEBITS);
    /* Cr=>G value is scaled-up -0.71414 * x */
    upsample->Cr_g_tab[i] = (- FIX(0.71414)) * x;
    /* Cb=>G value is scaled-up -0.34414 * x */
    /* We also add in ONE_HALF so that need not do it in inner loop */
    upsample->Cb_g_tab[i] = (- FIX(0.34414)) * x + ONE_HALF;
  }
}


/*
 * Initialize for an upsampling pass.
 */

METHODDEF(void)
start_pass_merged_upsample (j_decompress_ptr cinfo)
{
  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;

  /* Mark the spare buffer empty */
  upsample->spare_full = FALSE;
  /* Initialize total-height counter for detecting bottom of image */
  upsample->rows_to_go = cinfo->output_height;
}


/*
 * Control routine to do upsampling (and color conversion).
 *
 * The control routine just handles the row buffering considerations.
 */

METHODDEF(void)
merged_2v_upsample (j_decompress_ptr cinfo,
		    JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,
		    JDIMENSION in_row_groups_avail,
		    JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
		    JDIMENSION out_rows_avail)
/* 2:1 vertical sampling case: may need a spare row. */
{
  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
  JSAMPROW work_ptrs[2];
  JDIMENSION num_rows;		/* number of rows returned to caller */

  if (upsample->spare_full) {
    /* If we have a spare row saved from a previous cycle, just return it. */
    jcopy_sample_rows(& upsample->spare_row, 0, output_buf + *out_row_ctr, 0,
		      1, upsample->out_row_width);
    num_rows = 1;
    upsample->spare_full = FALSE;
  } else {
    /* Figure number of rows to return to caller. */
    num_rows = 2;
    /* Not more than the distance to the end of the image. */
    if (num_rows > upsample->rows_to_go)
      num_rows = upsample->rows_to_go;
    /* And not more than what the client can accept: */
    out_rows_avail -= *out_row_ctr;
    if (num_rows > out_rows_avail)
      num_rows = out_rows_avail;
    /* Create output pointer array for upsampler. */
    work_ptrs[0] = output_buf[*out_row_ctr];
    if (num_rows > 1) {
      work_ptrs[1] = output_buf[*out_row_ctr + 1];
    } else {
      work_ptrs[1] = upsample->spare_row;
      upsample->spare_full = TRUE;
    }
    /* Now do the upsampling. */
    (*upsample->upmethod) (cinfo, input_buf, *in_row_group_ctr, work_ptrs);
  }

  /* Adjust counts */
  *out_row_ctr += num_rows;
  upsample->rows_to_go -= num_rows;
  /* When the buffer is emptied, declare this input row group consumed */
  if (! upsample->spare_full)
    (*in_row_group_ctr)++;
}


METHODDEF(void)
merged_1v_upsample (j_decompress_ptr cinfo,
		    JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,
		    JDIMENSION in_row_groups_avail,
		    JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
		    JDIMENSION out_rows_avail)
/* 1:1 vertical sampling case: much easier, never need a spare row. */
{
  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;

  /* Just do the upsampling. */
  (*upsample->upmethod) (cinfo, input_buf, *in_row_group_ctr,
			 output_buf + *out_row_ctr);
  /* Adjust counts */
  (*out_row_ctr)++;
  (*in_row_group_ctr)++;
}


/*
 * These are the routines invoked by the control routines to do
 * the actual upsampling/conversion.  One row group is processed per call.
 *
 * Note: since we may be writing directly into application-supplied buffers,
 * we have to be honest about the output width; we can't assume the buffer
 * has been rounded up to an even width.
 */


/*
 * Upsample and color convert for the case of 2:1 horizontal and 1:1 vertical.
 */

METHODDEF(void)
h2v1_merged_upsample (j_decompress_ptr cinfo,
		      JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr,
		      JSAMPARRAY output_buf)
{
 

 my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
  register int y, cred, cgreen, cblue;
  int cb, cr;
  register JSAMPROW outptr;
  JSAMPROW inptr0, inptr1, inptr2;
  JDIMENSION col;
  /* copy these pointers into registers if possible */
  register JSAMPLE * range_limit = cinfo->sample_range_limit;
  int * Crrtab = upsample->Cr_r_tab;
  int * Cbbtab = upsample->Cb_b_tab;
  INT32 * Crgtab = upsample->Cr_g_tab;
  INT32 * Cbgtab = upsample->Cb_g_tab;
  SHIFT_TEMPS

  inptr0 = input_buf[0][in_row_group_ctr];
  inptr1 = input_buf[1][in_row_group_ctr];
  inptr2 = input_buf[2][in_row_group_ctr];
  outptr = output_buf[0];
  /* Loop for each pair of output pixels */
  for (col = cinfo->output_width >> 1; col > 0; col--) {
    /* Do the chroma part of the calculation */
    cb = GETJSAMPLE(*inptr1++);
    cr = GETJSAMPLE(*inptr2++);
    cred = Crrtab[cr];
    cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
    cblue = Cbbtab[cb];
    /* Fetch 2 Y values and emit 2 pixels */
    y  = GETJSAMPLE(*inptr0++);
    outptr[RGB_RED] =   range_limit[y + cred];
    outptr[RGB_GREEN] = range_limit[y + cgreen];
    outptr[RGB_BLUE] =  range_limit[y + cblue];
    outptr += RGB_PIXELSIZE;
    y  = GETJSAMPLE(*inptr0++);
    outptr[RGB_RED] =   range_limit[y + cred];
    outptr[RGB_GREEN] = range_limit[y + cgreen];
    outptr[RGB_BLUE] =  range_limit[y + cblue];
    outptr += RGB_PIXELSIZE;
  }
  /* If image width is odd, do the last output column separately */
  if (cinfo->output_width & 1) {
    cb = GETJSAMPLE(*inptr1);
    cr = GETJSAMPLE(*inptr2);
    cred = Crrtab[cr];
    cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
    cblue = Cbbtab[cb];
    y  = GETJSAMPLE(*inptr0);
    outptr[RGB_RED] =   range_limit[y + cred];
    outptr[RGB_GREEN] = range_limit[y + cgreen];
    outptr[RGB_BLUE] =  range_limit[y + cblue];
  }
}


/*
 * Upsample and color convert for the case of 2:1 horizontal and 2:1 vertical.
 */

#if defined(HAVE_MMX_INTEL_MNEMONICS) || defined(HAVE_MMX_ATT_MNEMONICS)
__inline METHODDEF(void)
h2v2_merged_upsample_orig (j_decompress_ptr cinfo,
		      JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr,
		      JSAMPARRAY output_buf);
__inline METHODDEF(void)
h2v2_merged_upsample_mmx (j_decompress_ptr cinfo,
		      JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr,
		      JSAMPARRAY output_buf);
#endif
 
METHODDEF(void)
h2v2_merged_upsample (j_decompress_ptr cinfo,
		      JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr,
		      JSAMPARRAY output_buf);

#if defined(HAVE_MMX_INTEL_MNEMONICS) || defined(HAVE_MMX_ATT_MNEMONICS)
METHODDEF(void)
h2v2_merged_upsample (j_decompress_ptr cinfo,
		      JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr,
		      JSAMPARRAY output_buf)
{
if (MMXAvailable && (cinfo->image_width >= 8))
	h2v2_merged_upsample_mmx (cinfo, input_buf, in_row_group_ctr, output_buf);
else
	h2v2_merged_upsample_orig (cinfo, input_buf, in_row_group_ctr, output_buf);

}

__inline METHODDEF(void)
h2v2_merged_upsample_orig (j_decompress_ptr cinfo,
		      JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr,
		      JSAMPARRAY output_buf)
{

  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
  register int y, cred, cgreen, cblue;
  int cb, cr;
  register JSAMPROW outptr0, outptr1;
  JSAMPROW inptr00, inptr01, inptr1, inptr2;
  JDIMENSION col;
  /* copy these pointers into registers if possible */
  register JSAMPLE * range_limit = cinfo->sample_range_limit;
  int * Crrtab = upsample->Cr_r_tab;
  int * Cbbtab = upsample->Cb_b_tab;
  INT32 * Crgtab = upsample->Cr_g_tab;
  INT32 * Cbgtab = upsample->Cb_g_tab;
  SHIFT_TEMPS

  inptr00 = input_buf[0][in_row_group_ctr*2];
  inptr01 = input_buf[0][in_row_group_ctr*2 + 1];
  inptr1 = input_buf[1][in_row_group_ctr];
  inptr2 = input_buf[2][in_row_group_ctr];
  outptr0 = output_buf[0];
  outptr1 = output_buf[1];
  /* Loop for each group of output pixels */
  for (col = cinfo->output_width >> 1; col > 0; col--) {
    /* Do the chroma part of the calculation */
    cb = GETJSAMPLE(*inptr1++);
    cr = GETJSAMPLE(*inptr2++);
    cred = Crrtab[cr];
    cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
    cblue = Cbbtab[cb];
    /* Fetch 4 Y values and emit 4 pixels */
    y  = GETJSAMPLE(*inptr00++);
    outptr0[RGB_RED] =   range_limit[y + cred];
    outptr0[RGB_GREEN] = range_limit[y + cgreen];
    outptr0[RGB_BLUE] =  range_limit[y + cblue];
    outptr0 += RGB_PIXELSIZE;
    y  = GETJSAMPLE(*inptr00++);
    outptr0[RGB_RED] =   range_limit[y + cred];
    outptr0[RGB_GREEN] = range_limit[y + cgreen];
    outptr0[RGB_BLUE] =  range_limit[y + cblue];
    outptr0 += RGB_PIXELSIZE;
    y  = GETJSAMPLE(*inptr01++);
    outptr1[RGB_RED] =   range_limit[y + cred];
    outptr1[RGB_GREEN] = range_limit[y + cgreen];
    outptr1[RGB_BLUE] =  range_limit[y + cblue];
    outptr1 += RGB_PIXELSIZE;
    y  = GETJSAMPLE(*inptr01++);
    outptr1[RGB_RED] =   range_limit[y + cred];
    outptr1[RGB_GREEN] = range_limit[y + cgreen];
    outptr1[RGB_BLUE] =  range_limit[y + cblue];
    outptr1 += RGB_PIXELSIZE;
  }
  /* If image width is odd, do the last output column separately */
  if (cinfo->output_width & 1) {
    cb = GETJSAMPLE(*inptr1);
    cr = GETJSAMPLE(*inptr2);
    cred = Crrtab[cr];
    cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
    cblue = Cbbtab[cb];
    y  = GETJSAMPLE(*inptr00);
    outptr0[RGB_RED] =   range_limit[y + cred];
    outptr0[RGB_GREEN] = range_limit[y + cgreen];
    outptr0[RGB_BLUE] =  range_limit[y + cblue];
    y  = GETJSAMPLE(*inptr01);
    outptr1[RGB_RED] =   range_limit[y + cred];
    outptr1[RGB_GREEN] = range_limit[y + cgreen];
    outptr1[RGB_BLUE] =  range_limit[y + cblue];
  }
}

/*
 * Upsample and color convert for the case of 2:1 horizontal and 2:1 vertical.
 */
__inline METHODDEF(void)
h2v2_merged_upsample_mmx (j_decompress_ptr cinfo,
		      JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr,
		      JSAMPARRAY output_buf)
{
  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
  register int y, cred, cgreen, cblue;
  int cb, cr;
  JSAMPROW outptr0, outptr1;
  JSAMPROW inptr00, inptr01, inptr1, inptr2;
  JDIMENSION col;
  /* copy these pointers into registers if possible */
  register JSAMPLE * range_limit = cinfo->sample_range_limit;
  int * Crrtab = upsample->Cr_r_tab;
  int * Cbbtab = upsample->Cb_b_tab;
  INT32 * Crgtab = upsample->Cr_g_tab;
  INT32 * Cbgtab = upsample->Cb_g_tab;
  SHIFT_TEMPS
  

  // Added for MMX	  
  register int width = cinfo->image_width;
  int cols = cinfo->output_width;
  int cols_asm = (cols >> 3);
  int diff = cols - (cols_asm<<3);
  int cols_asm_copy = cols_asm;

 ///////////////////////////////////////

  inptr00 = input_buf[0][in_row_group_ctr*2];
  inptr01 = input_buf[0][in_row_group_ctr*2 + 1];
  inptr1 = input_buf[1][in_row_group_ctr];
  inptr2 = input_buf[2][in_row_group_ctr];
  outptr0 = output_buf[0];
  outptr1 = output_buf[1];
  /* Loop for each group of output pixels */

#ifdef HAVE_MMX_INTEL_MNEMONICS
  _asm
  {
	  mov esi, inptr00

	  mov eax, inptr01
	  
	  mov ebx, inptr2

	  mov ecx, inptr1

	  mov edi, outptr0

	  mov edx, outptr1

do_next16:
	  
	  movd mm0, [ebx]			; Cr7 Cr6.....Cr1 Cr0

	  pxor mm6, mm6