#define JPEG_INTERNALS#include "jpeglib.h"#ifdef UPSAMPLE_MERGING_SUPPORTED/* 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. */METHODDEF(void)h2v2_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 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];  }}/* * Module initialization routine for merged upsampling/color conversion. * * NB: this is called under the conditions determined by use_merged_upsample() * in jdmaster.c.  That routine MUST correspond to the actual capabilities * of this module; no safety checks are made here. */GLOBAL(void)jinit_merged_upsampler (j_decompress_ptr cinfo){  my_upsample_ptr upsample;  upsample = (my_upsample_ptr)    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,				SIZEOF(my_upsampler));  cinfo->upsample = (struct jpeg_upsampler *) upsample;  upsample->pub.start_pass = start_pass_merged_upsample;  upsample->pub.need_context_rows = FALSE;  upsample->out_row_width = cinfo->output_width * cinfo->out_color_components;  if (cinfo->max_v_samp_factor == 2) {    upsample->pub.upsample = merged_2v_upsample;    upsample->upmethod = h2v2_merged_upsample;    /* Allocate a spare row buffer */    upsample->spare_row = (JSAMPROW)      (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE,		(size_t) (upsample->out_row_width * SIZEOF(JSAMPLE)));  } else {    upsample->pub.upsample = merged_1v_upsample;    upsample->upmethod = h2v1_merged_upsample;    /* No spare row needed */    upsample->spare_row = NULL;  }  build_ycc_rgb_table(cinfo);}#endif /* UPSAMPLE_MERGING_SUPPORTED */