144 lines
4.4 KiB
C
144 lines
4.4 KiB
C
/*
|
|
* jdcolext.c
|
|
*
|
|
* This file was part of the Independent JPEG Group's software:
|
|
* Copyright (C) 1991-1997, Thomas G. Lane.
|
|
* libjpeg-turbo Modifications:
|
|
* Copyright (C) 2009, 2011, 2015, D. R. Commander.
|
|
* For conditions of distribution and use, see the accompanying README.ijg
|
|
* file.
|
|
*
|
|
* This file contains output colorspace conversion routines.
|
|
*/
|
|
|
|
|
|
/* This file is included by jdcolor.c */
|
|
|
|
|
|
/*
|
|
* Convert some rows of samples to the output colorspace.
|
|
*
|
|
* Note that we change from noninterleaved, one-plane-per-component format
|
|
* to interleaved-pixel format. The output buffer is therefore three times
|
|
* as wide as the input buffer.
|
|
* A starting row offset is provided only for the input buffer. The caller
|
|
* can easily adjust the passed output_buf value to accommodate any row
|
|
* offset required on that side.
|
|
*/
|
|
|
|
INLINE
|
|
LOCAL(void)
|
|
ycc_rgb_convert_internal(j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
|
|
JDIMENSION input_row, JSAMPARRAY output_buf,
|
|
int num_rows)
|
|
{
|
|
my_cconvert_ptr cconvert = (my_cconvert_ptr)cinfo->cconvert;
|
|
register int y, cb, cr;
|
|
register JSAMPROW outptr;
|
|
register JSAMPROW inptr0, inptr1, inptr2;
|
|
register JDIMENSION col;
|
|
JDIMENSION num_cols = cinfo->output_width;
|
|
/* copy these pointers into registers if possible */
|
|
register JSAMPLE *range_limit = cinfo->sample_range_limit;
|
|
register int *Crrtab = cconvert->Cr_r_tab;
|
|
register int *Cbbtab = cconvert->Cb_b_tab;
|
|
register JLONG *Crgtab = cconvert->Cr_g_tab;
|
|
register JLONG *Cbgtab = cconvert->Cb_g_tab;
|
|
SHIFT_TEMPS
|
|
|
|
while (--num_rows >= 0) {
|
|
inptr0 = input_buf[0][input_row];
|
|
inptr1 = input_buf[1][input_row];
|
|
inptr2 = input_buf[2][input_row];
|
|
input_row++;
|
|
outptr = *output_buf++;
|
|
for (col = 0; col < num_cols; col++) {
|
|
y = GETJSAMPLE(inptr0[col]);
|
|
cb = GETJSAMPLE(inptr1[col]);
|
|
cr = GETJSAMPLE(inptr2[col]);
|
|
/* Range-limiting is essential due to noise introduced by DCT losses. */
|
|
outptr[RGB_RED] = range_limit[y + Crrtab[cr]];
|
|
outptr[RGB_GREEN] = range_limit[y +
|
|
((int)RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr],
|
|
SCALEBITS))];
|
|
outptr[RGB_BLUE] = range_limit[y + Cbbtab[cb]];
|
|
/* Set unused byte to 0xFF so it can be interpreted as an opaque */
|
|
/* alpha channel value */
|
|
#ifdef RGB_ALPHA
|
|
outptr[RGB_ALPHA] = 0xFF;
|
|
#endif
|
|
outptr += RGB_PIXELSIZE;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Convert grayscale to RGB: just duplicate the graylevel three times.
|
|
* This is provided to support applications that don't want to cope
|
|
* with grayscale as a separate case.
|
|
*/
|
|
|
|
INLINE
|
|
LOCAL(void)
|
|
gray_rgb_convert_internal(j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
|
|
JDIMENSION input_row, JSAMPARRAY output_buf,
|
|
int num_rows)
|
|
{
|
|
register JSAMPROW inptr, outptr;
|
|
register JDIMENSION col;
|
|
JDIMENSION num_cols = cinfo->output_width;
|
|
|
|
while (--num_rows >= 0) {
|
|
inptr = input_buf[0][input_row++];
|
|
outptr = *output_buf++;
|
|
for (col = 0; col < num_cols; col++) {
|
|
/* We can dispense with GETJSAMPLE() here */
|
|
outptr[RGB_RED] = outptr[RGB_GREEN] = outptr[RGB_BLUE] = inptr[col];
|
|
/* Set unused byte to 0xFF so it can be interpreted as an opaque */
|
|
/* alpha channel value */
|
|
#ifdef RGB_ALPHA
|
|
outptr[RGB_ALPHA] = 0xFF;
|
|
#endif
|
|
outptr += RGB_PIXELSIZE;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Convert RGB to extended RGB: just swap the order of source pixels
|
|
*/
|
|
|
|
INLINE
|
|
LOCAL(void)
|
|
rgb_rgb_convert_internal(j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
|
|
JDIMENSION input_row, JSAMPARRAY output_buf,
|
|
int num_rows)
|
|
{
|
|
register JSAMPROW inptr0, inptr1, inptr2;
|
|
register JSAMPROW outptr;
|
|
register JDIMENSION col;
|
|
JDIMENSION num_cols = cinfo->output_width;
|
|
|
|
while (--num_rows >= 0) {
|
|
inptr0 = input_buf[0][input_row];
|
|
inptr1 = input_buf[1][input_row];
|
|
inptr2 = input_buf[2][input_row];
|
|
input_row++;
|
|
outptr = *output_buf++;
|
|
for (col = 0; col < num_cols; col++) {
|
|
/* We can dispense with GETJSAMPLE() here */
|
|
outptr[RGB_RED] = inptr0[col];
|
|
outptr[RGB_GREEN] = inptr1[col];
|
|
outptr[RGB_BLUE] = inptr2[col];
|
|
/* Set unused byte to 0xFF so it can be interpreted as an opaque */
|
|
/* alpha channel value */
|
|
#ifdef RGB_ALPHA
|
|
outptr[RGB_ALPHA] = 0xFF;
|
|
#endif
|
|
outptr += RGB_PIXELSIZE;
|
|
}
|
|
}
|
|
}
|