/*
* jdmrgext.c
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1994-1996, Thomas G. Lane.
* libjpeg-turbo Modifications:
* Copyright (C) 2011, 2015, 2020, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
* file.
*
* This file contains code for merged upsampling/color conversion.
*/
/* This file is included by jdmerge.c */
/*
* Upsample and color convert for the case of 2:1 horizontal and 1:1 vertical.
*/
INLINE
LOCAL(void)
h2v1_merged_upsample_internal(j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
JDIMENSION in_row_group_ctr,
JSAMPARRAY output_buf)
{
my_merged_upsample_ptr upsample = (my_merged_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;
JLONG *Crgtab = upsample->Cr_g_tab;
JLONG *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 = *inptr1++;
cr = *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 = *inptr0++;
outptr[RGB_RED] = range_limit[y + cred];
outptr[RGB_GREEN] = range_limit[y + cgreen];
outptr[RGB_BLUE] = range_limit[y + cblue];
#ifdef RGB_ALPHA
outptr[RGB_ALPHA] = 0xFF;
#endif
outptr += RGB_PIXELSIZE;
y = *inptr0++;
outptr[RGB_RED] = range_limit[y + cred];
outptr[RGB_GREEN] = range_limit[y + cgreen];
outptr[RGB_BLUE] = range_limit[y + cblue];
#ifdef RGB_ALPHA
outptr[RGB_ALPHA] = 0xFF;
#endif
outptr += RGB_PIXELSIZE;
}
/* If image width is odd, do the last output column separately */
if (cinfo->output_width & 1) {
cb = *inptr1;
cr = *inptr2;
cred = Crrtab[cr];
cgreen = (int)RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
cblue = Cbbtab[cb];
y = *inptr0;
outptr[RGB_RED] = range_limit[y + cred];
outptr[RGB_GREEN] = range_limit[y + cgreen];
outptr[RGB_BLUE] = range_limit[y + cblue];
#ifdef RGB_ALPHA
outptr[RGB_ALPHA] = 0xFF;
#endif
}
}
/*
* Upsample and color convert for the case of 2:1 horizontal and 2:1 vertical.
*/
INLINE
LOCAL(void)
h2v2_merged_upsample_internal(j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
JDIMENSION in_row_group_ctr,
JSAMPARRAY output_buf)
{
my_merged_upsample_ptr upsample = (my_merged_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;
JLONG *Crgtab = upsample->Cr_g_tab;
JLONG *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 = *inptr1++;
cr = *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 = *inptr00++;
outptr0[RGB_RED] = range_limit[y + cred];
outptr0[RGB_GREEN] = range_limit[y + cgreen];
outptr0[RGB_BLUE] = range_limit[y + cblue];
#ifdef RGB_ALPHA
outptr0[RGB_ALPHA] = 0xFF;
#endif
outptr0 += RGB_PIXELSIZE;
y = *inptr00++;
outptr0[RGB_RED] = range_limit[y + cred];
outptr0[RGB_GREEN] = range_limit[y + cgreen];
outptr0[RGB_BLUE] = range_limit[y + cblue];
#ifdef RGB_ALPHA
outptr0[RGB_ALPHA] = 0xFF;
#endif
outptr0 += RGB_PIXELSIZE;
y = *inptr01++;
outptr1[RGB_RED] = range_limit[y + cred];
outptr1[RGB_GREEN] = range_limit[y + cgreen];
outptr1[RGB_BLUE] = range_limit[y + cblue];
#ifdef RGB_ALPHA
outptr1[RGB_ALPHA] = 0xFF;
#endif
outptr1 += RGB_PIXELSIZE;
y = *inptr01++;
outptr1[RGB_RED] = range_limit[y + cred];
outptr1[RGB_GREEN] = range_limit[y + cgreen];
outptr1[RGB_BLUE] = range_limit[y + cblue];
#ifdef RGB_ALPHA
outptr1[RGB_ALPHA] = 0xFF;
#endif
outptr1 += RGB_PIXELSIZE;
}
/* If image width is odd, do the last output column separately */
if (cinfo->output_width & 1) {
cb = *inptr1;
cr = *inptr2;
cred = Crrtab[cr];
cgreen = (int)RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
cblue = Cbbtab[cb];
y = *inptr00;
outptr0[RGB_RED] = range_limit[y + cred];
outptr0[RGB_GREEN] = range_limit[y + cgreen];
outptr0[RGB_BLUE] = range_limit[y + cblue];
#ifdef RGB_ALPHA
outptr0[RGB_ALPHA] = 0xFF;
#endif
y = *inptr01;
outptr1[RGB_RED] = range_limit[y + cred];
outptr1[RGB_GREEN] = range_limit[y + cgreen];
outptr1[RGB_BLUE] = range_limit[y + cblue];
#ifdef RGB_ALPHA
outptr1[RGB_ALPHA] = 0xFF;
#endif
}
}
