1 /*
2 * jdmrgext.c
3 *
4 * This file was part of the Independent JPEG Group's software:
5 * Copyright (C) 1994-1996, Thomas G. Lane.
6 * libjpeg-turbo Modifications:
7 * Copyright (C) 2011, D. R. Commander.
8 * For conditions of distribution and use, see the accompanying README file.
9 *
10 * This file contains code for merged upsampling/color conversion.
11 */
12
13
14 /* This file is included by jdmerge.c */
15
16
17 /*
18 * Upsample and color convert for the case of 2:1 horizontal and 1:1 vertical.
19 */
20
21 INLINE
LOCAL(void)22 LOCAL(void)
23 h2v1_merged_upsample_internal (j_decompress_ptr cinfo,
24 JSAMPIMAGE input_buf,
25 JDIMENSION in_row_group_ctr,
26 JSAMPARRAY output_buf)
27 {
28 my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
29 register int y, cred, cgreen, cblue;
30 int cb, cr;
31 register JSAMPROW outptr;
32 JSAMPROW inptr0, inptr1, inptr2;
33 JDIMENSION col;
34 /* copy these pointers into registers if possible */
35 register JSAMPLE * range_limit = cinfo->sample_range_limit;
36 int * Crrtab = upsample->Cr_r_tab;
37 int * Cbbtab = upsample->Cb_b_tab;
38 INT32 * Crgtab = upsample->Cr_g_tab;
39 INT32 * Cbgtab = upsample->Cb_g_tab;
40 SHIFT_TEMPS
41
42 inptr0 = input_buf[0][in_row_group_ctr];
43 inptr1 = input_buf[1][in_row_group_ctr];
44 inptr2 = input_buf[2][in_row_group_ctr];
45 outptr = output_buf[0];
46 /* Loop for each pair of output pixels */
47 for (col = cinfo->output_width >> 1; col > 0; col--) {
48 /* Do the chroma part of the calculation */
49 cb = GETJSAMPLE(*inptr1++);
50 cr = GETJSAMPLE(*inptr2++);
51 cred = Crrtab[cr];
52 cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
53 cblue = Cbbtab[cb];
54 /* Fetch 2 Y values and emit 2 pixels */
55 y = GETJSAMPLE(*inptr0++);
56 outptr[RGB_RED] = range_limit[y + cred];
57 outptr[RGB_GREEN] = range_limit[y + cgreen];
58 outptr[RGB_BLUE] = range_limit[y + cblue];
59 #ifdef RGB_ALPHA
60 outptr[RGB_ALPHA] = 0xFF;
61 #endif
62 outptr += RGB_PIXELSIZE;
63 y = GETJSAMPLE(*inptr0++);
64 outptr[RGB_RED] = range_limit[y + cred];
65 outptr[RGB_GREEN] = range_limit[y + cgreen];
66 outptr[RGB_BLUE] = range_limit[y + cblue];
67 #ifdef RGB_ALPHA
68 outptr[RGB_ALPHA] = 0xFF;
69 #endif
70 outptr += RGB_PIXELSIZE;
71 }
72 /* If image width is odd, do the last output column separately */
73 if (cinfo->output_width & 1) {
74 cb = GETJSAMPLE(*inptr1);
75 cr = GETJSAMPLE(*inptr2);
76 cred = Crrtab[cr];
77 cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
78 cblue = Cbbtab[cb];
79 y = GETJSAMPLE(*inptr0);
80 outptr[RGB_RED] = range_limit[y + cred];
81 outptr[RGB_GREEN] = range_limit[y + cgreen];
82 outptr[RGB_BLUE] = range_limit[y + cblue];
83 #ifdef RGB_ALPHA
84 outptr[RGB_ALPHA] = 0xFF;
85 #endif
86 }
87 }
88
89
90 /*
91 * Upsample and color convert for the case of 2:1 horizontal and 2:1 vertical.
92 */
93
94 INLINE
LOCAL(void)95 LOCAL(void)
96 h2v2_merged_upsample_internal (j_decompress_ptr cinfo,
97 JSAMPIMAGE input_buf,
98 JDIMENSION in_row_group_ctr,
99 JSAMPARRAY output_buf)
100 {
101 my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
102 register int y, cred, cgreen, cblue;
103 int cb, cr;
104 register JSAMPROW outptr0, outptr1;
105 JSAMPROW inptr00, inptr01, inptr1, inptr2;
106 JDIMENSION col;
107 /* copy these pointers into registers if possible */
108 register JSAMPLE * range_limit = cinfo->sample_range_limit;
109 int * Crrtab = upsample->Cr_r_tab;
110 int * Cbbtab = upsample->Cb_b_tab;
111 INT32 * Crgtab = upsample->Cr_g_tab;
112 INT32 * Cbgtab = upsample->Cb_g_tab;
113 SHIFT_TEMPS
114
115 inptr00 = input_buf[0][in_row_group_ctr*2];
116 inptr01 = input_buf[0][in_row_group_ctr*2 + 1];
117 inptr1 = input_buf[1][in_row_group_ctr];
118 inptr2 = input_buf[2][in_row_group_ctr];
119 outptr0 = output_buf[0];
120 outptr1 = output_buf[1];
121 /* Loop for each group of output pixels */
122 for (col = cinfo->output_width >> 1; col > 0; col--) {
123 /* Do the chroma part of the calculation */
124 cb = GETJSAMPLE(*inptr1++);
125 cr = GETJSAMPLE(*inptr2++);
126 cred = Crrtab[cr];
127 cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
128 cblue = Cbbtab[cb];
129 /* Fetch 4 Y values and emit 4 pixels */
130 y = GETJSAMPLE(*inptr00++);
131 outptr0[RGB_RED] = range_limit[y + cred];
132 outptr0[RGB_GREEN] = range_limit[y + cgreen];
133 outptr0[RGB_BLUE] = range_limit[y + cblue];
134 #ifdef RGB_ALPHA
135 outptr0[RGB_ALPHA] = 0xFF;
136 #endif
137 outptr0 += RGB_PIXELSIZE;
138 y = GETJSAMPLE(*inptr00++);
139 outptr0[RGB_RED] = range_limit[y + cred];
140 outptr0[RGB_GREEN] = range_limit[y + cgreen];
141 outptr0[RGB_BLUE] = range_limit[y + cblue];
142 #ifdef RGB_ALPHA
143 outptr0[RGB_ALPHA] = 0xFF;
144 #endif
145 outptr0 += RGB_PIXELSIZE;
146 y = GETJSAMPLE(*inptr01++);
147 outptr1[RGB_RED] = range_limit[y + cred];
148 outptr1[RGB_GREEN] = range_limit[y + cgreen];
149 outptr1[RGB_BLUE] = range_limit[y + cblue];
150 #ifdef RGB_ALPHA
151 outptr1[RGB_ALPHA] = 0xFF;
152 #endif
153 outptr1 += RGB_PIXELSIZE;
154 y = GETJSAMPLE(*inptr01++);
155 outptr1[RGB_RED] = range_limit[y + cred];
156 outptr1[RGB_GREEN] = range_limit[y + cgreen];
157 outptr1[RGB_BLUE] = range_limit[y + cblue];
158 #ifdef RGB_ALPHA
159 outptr1[RGB_ALPHA] = 0xFF;
160 #endif
161 outptr1 += RGB_PIXELSIZE;
162 }
163 /* If image width is odd, do the last output column separately */
164 if (cinfo->output_width & 1) {
165 cb = GETJSAMPLE(*inptr1);
166 cr = GETJSAMPLE(*inptr2);
167 cred = Crrtab[cr];
168 cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
169 cblue = Cbbtab[cb];
170 y = GETJSAMPLE(*inptr00);
171 outptr0[RGB_RED] = range_limit[y + cred];
172 outptr0[RGB_GREEN] = range_limit[y + cgreen];
173 outptr0[RGB_BLUE] = range_limit[y + cblue];
174 #ifdef RGB_ALPHA
175 outptr0[RGB_ALPHA] = 0xFF;
176 #endif
177 y = GETJSAMPLE(*inptr01);
178 outptr1[RGB_RED] = range_limit[y + cred];
179 outptr1[RGB_GREEN] = range_limit[y + cgreen];
180 outptr1[RGB_BLUE] = range_limit[y + cblue];
181 #ifdef RGB_ALPHA
182 outptr1[RGB_ALPHA] = 0xFF;
183 #endif
184 }
185 }
186