DRC | b4570bb | 2011-09-07 06:31:00 +0000 | [diff] [blame] | 1 | /* |
| 2 | * jdcolext.c |
| 3 | * |
DRC | a73e870 | 2012-12-31 02:52:30 +0000 | [diff] [blame] | 4 | * This file was part of the Independent JPEG Group's software: |
DRC | b4570bb | 2011-09-07 06:31:00 +0000 | [diff] [blame] | 5 | * Copyright (C) 1991-1997, Thomas G. Lane. |
DRC | a6ef282 | 2013-09-28 03:23:49 +0000 | [diff] [blame] | 6 | * libjpeg-turbo Modifications: |
DRC | b4570bb | 2011-09-07 06:31:00 +0000 | [diff] [blame] | 7 | * Copyright (C) 2009, 2011, D. R. Commander. |
DRC | b4570bb | 2011-09-07 06:31:00 +0000 | [diff] [blame] | 8 | * For conditions of distribution and use, see the accompanying README file. |
| 9 | * |
| 10 | * This file contains output colorspace conversion routines. |
| 11 | */ |
| 12 | |
| 13 | |
| 14 | /* This file is included by jdcolor.c */ |
| 15 | |
| 16 | |
| 17 | /* |
| 18 | * Convert some rows of samples to the output colorspace. |
| 19 | * |
| 20 | * Note that we change from noninterleaved, one-plane-per-component format |
| 21 | * to interleaved-pixel format. The output buffer is therefore three times |
| 22 | * as wide as the input buffer. |
| 23 | * A starting row offset is provided only for the input buffer. The caller |
| 24 | * can easily adjust the passed output_buf value to accommodate any row |
| 25 | * offset required on that side. |
| 26 | */ |
| 27 | |
| 28 | INLINE |
| 29 | LOCAL(void) |
| 30 | ycc_rgb_convert_internal (j_decompress_ptr cinfo, |
| 31 | JSAMPIMAGE input_buf, JDIMENSION input_row, |
| 32 | JSAMPARRAY output_buf, int num_rows) |
| 33 | { |
| 34 | my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; |
| 35 | register int y, cb, cr; |
| 36 | register JSAMPROW outptr; |
| 37 | register JSAMPROW inptr0, inptr1, inptr2; |
| 38 | register JDIMENSION col; |
| 39 | JDIMENSION num_cols = cinfo->output_width; |
| 40 | /* copy these pointers into registers if possible */ |
| 41 | register JSAMPLE * range_limit = cinfo->sample_range_limit; |
| 42 | register int * Crrtab = cconvert->Cr_r_tab; |
| 43 | register int * Cbbtab = cconvert->Cb_b_tab; |
| 44 | register INT32 * Crgtab = cconvert->Cr_g_tab; |
| 45 | register INT32 * Cbgtab = cconvert->Cb_g_tab; |
| 46 | SHIFT_TEMPS |
| 47 | |
| 48 | while (--num_rows >= 0) { |
| 49 | inptr0 = input_buf[0][input_row]; |
| 50 | inptr1 = input_buf[1][input_row]; |
| 51 | inptr2 = input_buf[2][input_row]; |
| 52 | input_row++; |
| 53 | outptr = *output_buf++; |
| 54 | for (col = 0; col < num_cols; col++) { |
| 55 | y = GETJSAMPLE(inptr0[col]); |
| 56 | cb = GETJSAMPLE(inptr1[col]); |
| 57 | cr = GETJSAMPLE(inptr2[col]); |
| 58 | /* Range-limiting is essential due to noise introduced by DCT losses. */ |
| 59 | outptr[RGB_RED] = range_limit[y + Crrtab[cr]]; |
| 60 | outptr[RGB_GREEN] = range_limit[y + |
| 61 | ((int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], |
| 62 | SCALEBITS))]; |
| 63 | outptr[RGB_BLUE] = range_limit[y + Cbbtab[cb]]; |
DRC | d89e01f | 2011-09-09 18:15:53 +0000 | [diff] [blame] | 64 | /* Set unused byte to 0xFF so it can be interpreted as an opaque */ |
| 65 | /* alpha channel value */ |
| 66 | #ifdef RGB_ALPHA |
| 67 | outptr[RGB_ALPHA] = 0xFF; |
| 68 | #endif |
DRC | b4570bb | 2011-09-07 06:31:00 +0000 | [diff] [blame] | 69 | outptr += RGB_PIXELSIZE; |
| 70 | } |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | |
| 75 | /* |
| 76 | * Convert grayscale to RGB: just duplicate the graylevel three times. |
| 77 | * This is provided to support applications that don't want to cope |
| 78 | * with grayscale as a separate case. |
| 79 | */ |
| 80 | |
| 81 | INLINE |
| 82 | LOCAL(void) |
| 83 | gray_rgb_convert_internal (j_decompress_ptr cinfo, |
| 84 | JSAMPIMAGE input_buf, JDIMENSION input_row, |
| 85 | JSAMPARRAY output_buf, int num_rows) |
| 86 | { |
| 87 | register JSAMPROW inptr, outptr; |
| 88 | register JDIMENSION col; |
| 89 | JDIMENSION num_cols = cinfo->output_width; |
| 90 | |
| 91 | while (--num_rows >= 0) { |
| 92 | inptr = input_buf[0][input_row++]; |
| 93 | outptr = *output_buf++; |
| 94 | for (col = 0; col < num_cols; col++) { |
DRC | b4570bb | 2011-09-07 06:31:00 +0000 | [diff] [blame] | 95 | /* We can dispense with GETJSAMPLE() here */ |
| 96 | outptr[RGB_RED] = outptr[RGB_GREEN] = outptr[RGB_BLUE] = inptr[col]; |
DRC | d89e01f | 2011-09-09 18:15:53 +0000 | [diff] [blame] | 97 | /* Set unused byte to 0xFF so it can be interpreted as an opaque */ |
| 98 | /* alpha channel value */ |
| 99 | #ifdef RGB_ALPHA |
| 100 | outptr[RGB_ALPHA] = 0xFF; |
| 101 | #endif |
DRC | b4570bb | 2011-09-07 06:31:00 +0000 | [diff] [blame] | 102 | outptr += RGB_PIXELSIZE; |
| 103 | } |
| 104 | } |
| 105 | } |
DRC | a9b646c | 2012-03-11 22:06:54 +0000 | [diff] [blame] | 106 | |
| 107 | |
| 108 | /* |
| 109 | * Convert RGB to extended RGB: just swap the order of source pixels |
| 110 | */ |
| 111 | |
| 112 | INLINE |
| 113 | LOCAL(void) |
| 114 | rgb_rgb_convert_internal (j_decompress_ptr cinfo, |
| 115 | JSAMPIMAGE input_buf, JDIMENSION input_row, |
| 116 | JSAMPARRAY output_buf, int num_rows) |
| 117 | { |
| 118 | register JSAMPROW inptr0, inptr1, inptr2; |
| 119 | register JSAMPROW outptr; |
| 120 | register JDIMENSION col; |
| 121 | JDIMENSION num_cols = cinfo->output_width; |
| 122 | |
| 123 | while (--num_rows >= 0) { |
| 124 | inptr0 = input_buf[0][input_row]; |
| 125 | inptr1 = input_buf[1][input_row]; |
| 126 | inptr2 = input_buf[2][input_row]; |
| 127 | input_row++; |
| 128 | outptr = *output_buf++; |
| 129 | for (col = 0; col < num_cols; col++) { |
| 130 | /* We can dispense with GETJSAMPLE() here */ |
| 131 | outptr[RGB_RED] = inptr0[col]; |
| 132 | outptr[RGB_GREEN] = inptr1[col]; |
| 133 | outptr[RGB_BLUE] = inptr2[col]; |
| 134 | /* Set unused byte to 0xFF so it can be interpreted as an opaque */ |
| 135 | /* alpha channel value */ |
| 136 | #ifdef RGB_ALPHA |
| 137 | outptr[RGB_ALPHA] = 0xFF; |
| 138 | #endif |
| 139 | outptr += RGB_PIXELSIZE; |
| 140 | } |
| 141 | } |
| 142 | } |