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gerrit-public.fairphone.software / platform / external / libjpeg-turbo / 69c1408e9d5ea1db45ae537b911c60088d813ad5 / . / jdmrgext.c
blob: 95ddd556230fb1c63e73e926a4423ae2c082e26f [file] [log] [blame]
DRCb4570bb2011-09-07 06:31:00 +0000[diff] [blame]1/*
2 * jdmrgext.c
3 *
4 * Copyright (C) 1994-1996, Thomas G. Lane.
5 * This file is part of the Independent JPEG Group's software.
6 * For conditions of distribution and use, see the accompanying README file.
7 *
8 * This file contains code for merged upsampling/color conversion.
9 */
10
11
12/* This file is included by jdmerge.c */
13
14
15/*
16 * Upsample and color convert for the case of 2:1 horizontal and 1:1 vertical.
17 */
18
19INLINE
20LOCAL(void)
21h2v1_merged_upsample_internal (j_decompress_ptr cinfo,
22 JSAMPIMAGE input_buf,
23 JDIMENSION in_row_group_ctr,
24 JSAMPARRAY output_buf)
25{
26 my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
27 register int y, cred, cgreen, cblue;
28 int cb, cr;
29 register JSAMPROW outptr;
30 JSAMPROW inptr0, inptr1, inptr2;
31 JDIMENSION col;
32 /* copy these pointers into registers if possible */
33 register JSAMPLE * range_limit = cinfo->sample_range_limit;
34 int * Crrtab = upsample->Cr_r_tab;
35 int * Cbbtab = upsample->Cb_b_tab;
36 INT32 * Crgtab = upsample->Cr_g_tab;
37 INT32 * Cbgtab = upsample->Cb_g_tab;
38 SHIFT_TEMPS
39
40 inptr0 = input_buf[0][in_row_group_ctr];
41 inptr1 = input_buf[1][in_row_group_ctr];
42 inptr2 = input_buf[2][in_row_group_ctr];
43 outptr = output_buf[0];
44 /* Loop for each pair of output pixels */
45 for (col = cinfo->output_width >> 1; col > 0; col--) {
46 /* Do the chroma part of the calculation */
47 cb = GETJSAMPLE(*inptr1++);
48 cr = GETJSAMPLE(*inptr2++);
49 cred = Crrtab[cr];
50 cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
51 cblue = Cbbtab[cb];
52 /* Fetch 2 Y values and emit 2 pixels */
53 y = GETJSAMPLE(*inptr0++);
54 outptr[RGB_RED] = range_limit[y + cred];
55 outptr[RGB_GREEN] = range_limit[y + cgreen];
56 outptr[RGB_BLUE] = range_limit[y + cblue];
57 outptr += RGB_PIXELSIZE;
58 y = GETJSAMPLE(*inptr0++);
59 outptr[RGB_RED] = range_limit[y + cred];
60 outptr[RGB_GREEN] = range_limit[y + cgreen];
61 outptr[RGB_BLUE] = range_limit[y + cblue];
62 outptr += RGB_PIXELSIZE;
63 }
64 /* If image width is odd, do the last output column separately */
65 if (cinfo->output_width & 1) {
66 cb = GETJSAMPLE(*inptr1);
67 cr = GETJSAMPLE(*inptr2);
68 cred = Crrtab[cr];
69 cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
70 cblue = Cbbtab[cb];
71 y = GETJSAMPLE(*inptr0);
72 outptr[RGB_RED] = range_limit[y + cred];
73 outptr[RGB_GREEN] = range_limit[y + cgreen];
74 outptr[RGB_BLUE] = range_limit[y + cblue];
75 }
76}
77
78
79/*
80 * Upsample and color convert for the case of 2:1 horizontal and 2:1 vertical.
81 */
82
83INLINE
84LOCAL(void)
85h2v2_merged_upsample_internal (j_decompress_ptr cinfo,
86 JSAMPIMAGE input_buf,
87 JDIMENSION in_row_group_ctr,
88 JSAMPARRAY output_buf)
89{
90 my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
91 register int y, cred, cgreen, cblue;
92 int cb, cr;
93 register JSAMPROW outptr0, outptr1;
94 JSAMPROW inptr00, inptr01, inptr1, inptr2;
95 JDIMENSION col;
96 /* copy these pointers into registers if possible */
97 register JSAMPLE * range_limit = cinfo->sample_range_limit;
98 int * Crrtab = upsample->Cr_r_tab;
99 int * Cbbtab = upsample->Cb_b_tab;
100 INT32 * Crgtab = upsample->Cr_g_tab;
101 INT32 * Cbgtab = upsample->Cb_g_tab;
102 SHIFT_TEMPS
103
104 inptr00 = input_buf[0][in_row_group_ctr*2];
105 inptr01 = input_buf[0][in_row_group_ctr*2 + 1];
106 inptr1 = input_buf[1][in_row_group_ctr];
107 inptr2 = input_buf[2][in_row_group_ctr];
108 outptr0 = output_buf[0];
109 outptr1 = output_buf[1];
110 /* Loop for each group of output pixels */
111 for (col = cinfo->output_width >> 1; col > 0; col--) {
112 /* Do the chroma part of the calculation */
113 cb = GETJSAMPLE(*inptr1++);
114 cr = GETJSAMPLE(*inptr2++);
115 cred = Crrtab[cr];
116 cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
117 cblue = Cbbtab[cb];
118 /* Fetch 4 Y values and emit 4 pixels */
119 y = GETJSAMPLE(*inptr00++);
120 outptr0[RGB_RED] = range_limit[y + cred];
121 outptr0[RGB_GREEN] = range_limit[y + cgreen];
122 outptr0[RGB_BLUE] = range_limit[y + cblue];
123 outptr0 += RGB_PIXELSIZE;
124 y = GETJSAMPLE(*inptr00++);
125 outptr0[RGB_RED] = range_limit[y + cred];
126 outptr0[RGB_GREEN] = range_limit[y + cgreen];
127 outptr0[RGB_BLUE] = range_limit[y + cblue];
128 outptr0 += RGB_PIXELSIZE;
129 y = GETJSAMPLE(*inptr01++);
130 outptr1[RGB_RED] = range_limit[y + cred];
131 outptr1[RGB_GREEN] = range_limit[y + cgreen];
132 outptr1[RGB_BLUE] = range_limit[y + cblue];
133 outptr1 += RGB_PIXELSIZE;
134 y = GETJSAMPLE(*inptr01++);
135 outptr1[RGB_RED] = range_limit[y + cred];
136 outptr1[RGB_GREEN] = range_limit[y + cgreen];
137 outptr1[RGB_BLUE] = range_limit[y + cblue];
138 outptr1 += RGB_PIXELSIZE;
139 }
140 /* If image width is odd, do the last output column separately */
141 if (cinfo->output_width & 1) {
142 cb = GETJSAMPLE(*inptr1);
143 cr = GETJSAMPLE(*inptr2);
144 cred = Crrtab[cr];
145 cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
146 cblue = Cbbtab[cb];
147 y = GETJSAMPLE(*inptr00);
148 outptr0[RGB_RED] = range_limit[y + cred];
149 outptr0[RGB_GREEN] = range_limit[y + cgreen];
150 outptr0[RGB_BLUE] = range_limit[y + cblue];
151 y = GETJSAMPLE(*inptr01);
152 outptr1[RGB_RED] = range_limit[y + cred];
153 outptr1[RGB_GREEN] = range_limit[y + cgreen];
154 outptr1[RGB_BLUE] = range_limit[y + cblue];
155 }
156}