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, 2015, D. R. Commander. 8 * For conditions of distribution and use, see the accompanying README.ijg 9 * file. 10 * 11 * This file contains code for merged upsampling/color conversion. 12 */ 13 14 15 /* This file is included by jdmerge.c */ 16 17 18 /* 19 * Upsample and color convert for the case of 2:1 horizontal and 1:1 vertical. 20 */ 21 22 INLINE 23 LOCAL(void) 24 h2v1_merged_upsample_internal (j_decompress_ptr cinfo, 25 JSAMPIMAGE input_buf, 26 JDIMENSION in_row_group_ctr, 27 JSAMPARRAY output_buf) 28 { 29 my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample; 30 register int y, cred, cgreen, cblue; 31 int cb, cr; 32 register JSAMPROW outptr; 33 JSAMPROW inptr0, inptr1, inptr2; 34 JDIMENSION col; 35 /* copy these pointers into registers if possible */ 36 register JSAMPLE * range_limit = cinfo->sample_range_limit; 37 int * Crrtab = upsample->Cr_r_tab; 38 int * Cbbtab = upsample->Cb_b_tab; 39 JLONG * Crgtab = upsample->Cr_g_tab; 40 JLONG * Cbgtab = upsample->Cb_g_tab; 41 SHIFT_TEMPS 42 43 inptr0 = input_buf[0][in_row_group_ctr]; 44 inptr1 = input_buf[1][in_row_group_ctr]; 45 inptr2 = input_buf[2][in_row_group_ctr]; 46 outptr = output_buf[0]; 47 /* Loop for each pair of output pixels */ 48 for (col = cinfo->output_width >> 1; col > 0; col--) { 49 /* Do the chroma part of the calculation */ 50 cb = GETJSAMPLE(*inptr1++); 51 cr = GETJSAMPLE(*inptr2++); 52 cred = Crrtab[cr]; 53 cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS); 54 cblue = Cbbtab[cb]; 55 /* Fetch 2 Y values and emit 2 pixels */ 56 y = GETJSAMPLE(*inptr0++); 57 outptr[RGB_RED] = range_limit[y + cred]; 58 outptr[RGB_GREEN] = range_limit[y + cgreen]; 59 outptr[RGB_BLUE] = range_limit[y + cblue]; 60 #ifdef RGB_ALPHA 61 outptr[RGB_ALPHA] = 0xFF; 62 #endif 63 outptr += RGB_PIXELSIZE; 64 y = GETJSAMPLE(*inptr0++); 65 outptr[RGB_RED] = range_limit[y + cred]; 66 outptr[RGB_GREEN] = range_limit[y + cgreen]; 67 outptr[RGB_BLUE] = range_limit[y + cblue]; 68 #ifdef RGB_ALPHA 69 outptr[RGB_ALPHA] = 0xFF; 70 #endif 71 outptr += RGB_PIXELSIZE; 72 } 73 /* If image width is odd, do the last output column separately */ 74 if (cinfo->output_width & 1) { 75 cb = GETJSAMPLE(*inptr1); 76 cr = GETJSAMPLE(*inptr2); 77 cred = Crrtab[cr]; 78 cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS); 79 cblue = Cbbtab[cb]; 80 y = GETJSAMPLE(*inptr0); 81 outptr[RGB_RED] = range_limit[y + cred]; 82 outptr[RGB_GREEN] = range_limit[y + cgreen]; 83 outptr[RGB_BLUE] = range_limit[y + cblue]; 84 #ifdef RGB_ALPHA 85 outptr[RGB_ALPHA] = 0xFF; 86 #endif 87 } 88 } 89 90 91 /* 92 * Upsample and color convert for the case of 2:1 horizontal and 2:1 vertical. 93 */ 94 95 INLINE 96 LOCAL(void) 97 h2v2_merged_upsample_internal (j_decompress_ptr cinfo, 98 JSAMPIMAGE input_buf, 99 JDIMENSION in_row_group_ctr, 100 JSAMPARRAY output_buf) 101 { 102 my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample; 103 register int y, cred, cgreen, cblue; 104 int cb, cr; 105 register JSAMPROW outptr0, outptr1; 106 JSAMPROW inptr00, inptr01, inptr1, inptr2; 107 JDIMENSION col; 108 /* copy these pointers into registers if possible */ 109 register JSAMPLE * range_limit = cinfo->sample_range_limit; 110 int * Crrtab = upsample->Cr_r_tab; 111 int * Cbbtab = upsample->Cb_b_tab; 112 JLONG * Crgtab = upsample->Cr_g_tab; 113 JLONG * Cbgtab = upsample->Cb_g_tab; 114 SHIFT_TEMPS 115 116 inptr00 = input_buf[0][in_row_group_ctr*2]; 117 inptr01 = input_buf[0][in_row_group_ctr*2 + 1]; 118 inptr1 = input_buf[1][in_row_group_ctr]; 119 inptr2 = input_buf[2][in_row_group_ctr]; 120 outptr0 = output_buf[0]; 121 outptr1 = output_buf[1]; 122 /* Loop for each group of output pixels */ 123 for (col = cinfo->output_width >> 1; col > 0; col--) { 124 /* Do the chroma part of the calculation */ 125 cb = GETJSAMPLE(*inptr1++); 126 cr = GETJSAMPLE(*inptr2++); 127 cred = Crrtab[cr]; 128 cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS); 129 cblue = Cbbtab[cb]; 130 /* Fetch 4 Y values and emit 4 pixels */ 131 y = GETJSAMPLE(*inptr00++); 132 outptr0[RGB_RED] = range_limit[y + cred]; 133 outptr0[RGB_GREEN] = range_limit[y + cgreen]; 134 outptr0[RGB_BLUE] = range_limit[y + cblue]; 135 #ifdef RGB_ALPHA 136 outptr0[RGB_ALPHA] = 0xFF; 137 #endif 138 outptr0 += RGB_PIXELSIZE; 139 y = GETJSAMPLE(*inptr00++); 140 outptr0[RGB_RED] = range_limit[y + cred]; 141 outptr0[RGB_GREEN] = range_limit[y + cgreen]; 142 outptr0[RGB_BLUE] = range_limit[y + cblue]; 143 #ifdef RGB_ALPHA 144 outptr0[RGB_ALPHA] = 0xFF; 145 #endif 146 outptr0 += RGB_PIXELSIZE; 147 y = GETJSAMPLE(*inptr01++); 148 outptr1[RGB_RED] = range_limit[y + cred]; 149 outptr1[RGB_GREEN] = range_limit[y + cgreen]; 150 outptr1[RGB_BLUE] = range_limit[y + cblue]; 151 #ifdef RGB_ALPHA 152 outptr1[RGB_ALPHA] = 0xFF; 153 #endif 154 outptr1 += RGB_PIXELSIZE; 155 y = GETJSAMPLE(*inptr01++); 156 outptr1[RGB_RED] = range_limit[y + cred]; 157 outptr1[RGB_GREEN] = range_limit[y + cgreen]; 158 outptr1[RGB_BLUE] = range_limit[y + cblue]; 159 #ifdef RGB_ALPHA 160 outptr1[RGB_ALPHA] = 0xFF; 161 #endif 162 outptr1 += RGB_PIXELSIZE; 163 } 164 /* If image width is odd, do the last output column separately */ 165 if (cinfo->output_width & 1) { 166 cb = GETJSAMPLE(*inptr1); 167 cr = GETJSAMPLE(*inptr2); 168 cred = Crrtab[cr]; 169 cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS); 170 cblue = Cbbtab[cb]; 171 y = GETJSAMPLE(*inptr00); 172 outptr0[RGB_RED] = range_limit[y + cred]; 173 outptr0[RGB_GREEN] = range_limit[y + cgreen]; 174 outptr0[RGB_BLUE] = range_limit[y + cblue]; 175 #ifdef RGB_ALPHA 176 outptr0[RGB_ALPHA] = 0xFF; 177 #endif 178 y = GETJSAMPLE(*inptr01); 179 outptr1[RGB_RED] = range_limit[y + cred]; 180 outptr1[RGB_GREEN] = range_limit[y + cgreen]; 181 outptr1[RGB_BLUE] = range_limit[y + cblue]; 182 #ifdef RGB_ALPHA 183 outptr1[RGB_ALPHA] = 0xFF; 184 #endif 185 } 186 } 187
