Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 1 | // Copyright 2012 Google Inc. All Rights Reserved. |
| 2 | // |
Vikas Arora | 0406ce1 | 2013-08-09 15:57:12 -0700 | [diff] [blame] | 3 | // Use of this source code is governed by a BSD-style license |
| 4 | // that can be found in the COPYING file in the root of the source |
| 5 | // tree. An additional intellectual property rights grant can be found |
| 6 | // in the file PATENTS. All contributing project authors may |
| 7 | // be found in the AUTHORS file in the root of the source tree. |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 8 | // ----------------------------------------------------------------------------- |
| 9 | // |
| 10 | // Rescaling functions |
| 11 | // |
| 12 | // Author: Skal (pascal.massimino@gmail.com) |
| 13 | |
| 14 | #include <assert.h> |
| 15 | #include <stdlib.h> |
| 16 | #include "./rescaler.h" |
Vikas Arora | af51b94 | 2014-08-28 10:51:12 -0700 | [diff] [blame] | 17 | #include "../dsp/dsp.h" |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 18 | |
| 19 | //------------------------------------------------------------------------------ |
Vikas Arora | af51b94 | 2014-08-28 10:51:12 -0700 | [diff] [blame] | 20 | // Implementations of critical functions ImportRow / ExportRow |
| 21 | |
| 22 | void (*WebPRescalerImportRow)(WebPRescaler* const wrk, |
| 23 | const uint8_t* const src, int channel) = NULL; |
| 24 | void (*WebPRescalerExportRow)(WebPRescaler* const wrk, int x_out) = NULL; |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 25 | |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 26 | #define RFIX 30 |
Vikas Arora | 0406ce1 | 2013-08-09 15:57:12 -0700 | [diff] [blame] | 27 | #define MULT_FIX(x, y) (((int64_t)(x) * (y) + (1 << (RFIX - 1))) >> RFIX) |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 28 | |
Vikas Arora | af51b94 | 2014-08-28 10:51:12 -0700 | [diff] [blame] | 29 | static void ImportRowC(WebPRescaler* const wrk, |
| 30 | const uint8_t* const src, int channel) { |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 31 | const int x_stride = wrk->num_channels; |
| 32 | const int x_out_max = wrk->dst_width * wrk->num_channels; |
| 33 | int x_in = channel; |
| 34 | int x_out; |
| 35 | int accum = 0; |
| 36 | if (!wrk->x_expand) { |
| 37 | int sum = 0; |
| 38 | for (x_out = channel; x_out < x_out_max; x_out += x_stride) { |
| 39 | accum += wrk->x_add; |
| 40 | for (; accum > 0; accum -= wrk->x_sub) { |
| 41 | sum += src[x_in]; |
| 42 | x_in += x_stride; |
| 43 | } |
| 44 | { // Emit next horizontal pixel. |
| 45 | const int32_t base = src[x_in]; |
| 46 | const int32_t frac = base * (-accum); |
| 47 | x_in += x_stride; |
| 48 | wrk->frow[x_out] = (sum + base) * wrk->x_sub - frac; |
| 49 | // fresh fractional start for next pixel |
| 50 | sum = (int)MULT_FIX(frac, wrk->fx_scale); |
| 51 | } |
| 52 | } |
| 53 | } else { // simple bilinear interpolation |
| 54 | int left = src[channel], right = src[channel]; |
| 55 | for (x_out = channel; x_out < x_out_max; x_out += x_stride) { |
| 56 | if (accum < 0) { |
| 57 | left = right; |
| 58 | x_in += x_stride; |
| 59 | right = src[x_in]; |
| 60 | accum += wrk->x_add; |
| 61 | } |
| 62 | wrk->frow[x_out] = right * wrk->x_add + (left - right) * accum; |
| 63 | accum -= wrk->x_sub; |
| 64 | } |
| 65 | } |
Vikas Arora | af51b94 | 2014-08-28 10:51:12 -0700 | [diff] [blame] | 66 | // Accumulate the contribution of the new row. |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 67 | for (x_out = channel; x_out < x_out_max; x_out += x_stride) { |
| 68 | wrk->irow[x_out] += wrk->frow[x_out]; |
| 69 | } |
| 70 | } |
| 71 | |
Vikas Arora | af51b94 | 2014-08-28 10:51:12 -0700 | [diff] [blame] | 72 | static void ExportRowC(WebPRescaler* const wrk, int x_out) { |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 73 | if (wrk->y_accum <= 0) { |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 74 | uint8_t* const dst = wrk->dst; |
| 75 | int32_t* const irow = wrk->irow; |
| 76 | const int32_t* const frow = wrk->frow; |
| 77 | const int yscale = wrk->fy_scale * (-wrk->y_accum); |
| 78 | const int x_out_max = wrk->dst_width * wrk->num_channels; |
Vikas Arora | af51b94 | 2014-08-28 10:51:12 -0700 | [diff] [blame] | 79 | for (; x_out < x_out_max; ++x_out) { |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 80 | const int frac = (int)MULT_FIX(frow[x_out], yscale); |
| 81 | const int v = (int)MULT_FIX(irow[x_out] - frac, wrk->fxy_scale); |
| 82 | dst[x_out] = (!(v & ~0xff)) ? v : (v < 0) ? 0 : 255; |
| 83 | irow[x_out] = frac; // new fractional start |
| 84 | } |
| 85 | wrk->y_accum += wrk->y_add; |
| 86 | wrk->dst += wrk->dst_stride; |
Vikas Arora | af51b94 | 2014-08-28 10:51:12 -0700 | [diff] [blame] | 87 | } |
| 88 | } |
| 89 | |
| 90 | //------------------------------------------------------------------------------ |
| 91 | // MIPS version |
| 92 | |
| 93 | #if defined(WEBP_USE_MIPS32) |
| 94 | |
| 95 | static void ImportRowMIPS(WebPRescaler* const wrk, |
| 96 | const uint8_t* const src, int channel) { |
| 97 | const int x_stride = wrk->num_channels; |
| 98 | const int x_out_max = wrk->dst_width * wrk->num_channels; |
| 99 | const int fx_scale = wrk->fx_scale; |
| 100 | const int x_add = wrk->x_add; |
| 101 | const int x_sub = wrk->x_sub; |
| 102 | int* frow = wrk->frow + channel; |
| 103 | int* irow = wrk->irow + channel; |
| 104 | const uint8_t* src1 = src + channel; |
| 105 | int temp1, temp2, temp3; |
| 106 | int base, frac, sum; |
| 107 | int accum, accum1; |
| 108 | const int x_stride1 = x_stride << 2; |
| 109 | int loop_c = x_out_max - channel; |
| 110 | |
| 111 | if (!wrk->x_expand) { |
| 112 | __asm__ volatile ( |
| 113 | "li %[temp1], 0x8000 \n\t" |
| 114 | "li %[temp2], 0x10000 \n\t" |
| 115 | "li %[sum], 0 \n\t" |
| 116 | "li %[accum], 0 \n\t" |
| 117 | "1: \n\t" |
| 118 | "addu %[accum], %[accum], %[x_add] \n\t" |
| 119 | "blez %[accum], 3f \n\t" |
| 120 | "2: \n\t" |
| 121 | "lbu %[temp3], 0(%[src1]) \n\t" |
| 122 | "subu %[accum], %[accum], %[x_sub] \n\t" |
| 123 | "addu %[src1], %[src1], %[x_stride] \n\t" |
| 124 | "addu %[sum], %[sum], %[temp3] \n\t" |
| 125 | "bgtz %[accum], 2b \n\t" |
| 126 | "3: \n\t" |
| 127 | "lbu %[base], 0(%[src1]) \n\t" |
| 128 | "addu %[src1], %[src1], %[x_stride] \n\t" |
| 129 | "negu %[accum1], %[accum] \n\t" |
| 130 | "mul %[frac], %[base], %[accum1] \n\t" |
| 131 | "addu %[temp3], %[sum], %[base] \n\t" |
| 132 | "mul %[temp3], %[temp3], %[x_sub] \n\t" |
| 133 | "lw %[base], 0(%[irow]) \n\t" |
| 134 | "subu %[loop_c], %[loop_c], %[x_stride] \n\t" |
| 135 | "sll %[accum1], %[frac], 2 \n\t" |
| 136 | "mult %[temp1], %[temp2] \n\t" |
| 137 | "madd %[accum1], %[fx_scale] \n\t" |
| 138 | "mfhi %[sum] \n\t" |
| 139 | "subu %[temp3], %[temp3], %[frac] \n\t" |
| 140 | "sw %[temp3], 0(%[frow]) \n\t" |
| 141 | "add %[base], %[base], %[temp3] \n\t" |
| 142 | "sw %[base], 0(%[irow]) \n\t" |
| 143 | "addu %[irow], %[irow], %[x_stride1] \n\t" |
| 144 | "addu %[frow], %[frow], %[x_stride1] \n\t" |
| 145 | "bgtz %[loop_c], 1b \n\t" |
| 146 | |
| 147 | : [accum] "=&r" (accum), [src1] "+r" (src1), [temp3] "=&r" (temp3), |
| 148 | [sum] "=&r" (sum), [base] "=&r" (base), [frac] "=&r" (frac), |
| 149 | [frow] "+r" (frow), [irow] "+r" (irow), [accum1] "=&r" (accum1), |
| 150 | [temp2] "=&r" (temp2), [temp1] "=&r" (temp1) |
| 151 | : [x_stride] "r" (x_stride), [fx_scale] "r" (fx_scale), |
| 152 | [x_sub] "r" (x_sub), [x_add] "r" (x_add), |
| 153 | [loop_c] "r" (loop_c), [x_stride1] "r" (x_stride1) |
| 154 | : "memory", "hi", "lo" |
| 155 | ); |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 156 | } else { |
Vikas Arora | af51b94 | 2014-08-28 10:51:12 -0700 | [diff] [blame] | 157 | __asm__ volatile ( |
| 158 | "lbu %[temp1], 0(%[src1]) \n\t" |
| 159 | "move %[temp2], %[temp1] \n\t" |
| 160 | "li %[accum], 0 \n\t" |
| 161 | "1: \n\t" |
| 162 | "bgez %[accum], 2f \n\t" |
| 163 | "move %[temp2], %[temp1] \n\t" |
| 164 | "addu %[src1], %[x_stride] \n\t" |
| 165 | "lbu %[temp1], 0(%[src1]) \n\t" |
| 166 | "addu %[accum], %[x_add] \n\t" |
| 167 | "2: \n\t" |
| 168 | "subu %[temp3], %[temp2], %[temp1] \n\t" |
| 169 | "mul %[temp3], %[temp3], %[accum] \n\t" |
| 170 | "mul %[base], %[temp1], %[x_add] \n\t" |
| 171 | "subu %[accum], %[accum], %[x_sub] \n\t" |
| 172 | "lw %[frac], 0(%[irow]) \n\t" |
| 173 | "subu %[loop_c], %[loop_c], %[x_stride] \n\t" |
| 174 | "addu %[temp3], %[base], %[temp3] \n\t" |
| 175 | "sw %[temp3], 0(%[frow]) \n\t" |
| 176 | "addu %[frow], %[x_stride1] \n\t" |
| 177 | "addu %[frac], %[temp3] \n\t" |
| 178 | "sw %[frac], 0(%[irow]) \n\t" |
| 179 | "addu %[irow], %[x_stride1] \n\t" |
| 180 | "bgtz %[loop_c], 1b \n\t" |
| 181 | |
| 182 | : [src1] "+r" (src1), [accum] "=&r" (accum), [temp1] "=&r" (temp1), |
| 183 | [temp2] "=&r" (temp2), [temp3] "=&r" (temp3), [base] "=&r" (base), |
| 184 | [frac] "=&r" (frac), [frow] "+r" (frow), [irow] "+r" (irow) |
| 185 | : [x_stride] "r" (x_stride), [x_add] "r" (x_add), [x_sub] "r" (x_sub), |
| 186 | [x_stride1] "r" (x_stride1), [loop_c] "r" (loop_c) |
| 187 | : "memory", "hi", "lo" |
| 188 | ); |
| 189 | } |
| 190 | } |
| 191 | |
| 192 | static void ExportRowMIPS(WebPRescaler* const wrk, int x_out) { |
| 193 | if (wrk->y_accum <= 0) { |
| 194 | uint8_t* const dst = wrk->dst; |
| 195 | int32_t* const irow = wrk->irow; |
| 196 | const int32_t* const frow = wrk->frow; |
| 197 | const int yscale = wrk->fy_scale * (-wrk->y_accum); |
| 198 | const int x_out_max = wrk->dst_width * wrk->num_channels; |
| 199 | // if wrk->fxy_scale can fit into 32 bits use optimized code, |
| 200 | // otherwise use C code |
| 201 | if ((wrk->fxy_scale >> 32) == 0) { |
| 202 | int temp0, temp1, temp3, temp4, temp5, temp6, temp7, loop_end; |
| 203 | const int temp2 = (int)(wrk->fxy_scale); |
| 204 | const int temp8 = x_out_max << 2; |
| 205 | uint8_t* dst_t = (uint8_t*)dst; |
| 206 | int32_t* irow_t = (int32_t*)irow; |
| 207 | const int32_t* frow_t = (const int32_t*)frow; |
| 208 | |
| 209 | __asm__ volatile( |
| 210 | "addiu %[temp6], $zero, -256 \n\t" |
| 211 | "addiu %[temp7], $zero, 255 \n\t" |
| 212 | "li %[temp3], 0x10000 \n\t" |
| 213 | "li %[temp4], 0x8000 \n\t" |
| 214 | "addu %[loop_end], %[frow_t], %[temp8] \n\t" |
| 215 | "1: \n\t" |
| 216 | "lw %[temp0], 0(%[frow_t]) \n\t" |
| 217 | "mult %[temp3], %[temp4] \n\t" |
| 218 | "addiu %[frow_t], %[frow_t], 4 \n\t" |
| 219 | "sll %[temp0], %[temp0], 2 \n\t" |
| 220 | "madd %[temp0], %[yscale] \n\t" |
| 221 | "mfhi %[temp1] \n\t" |
| 222 | "lw %[temp0], 0(%[irow_t]) \n\t" |
| 223 | "addiu %[dst_t], %[dst_t], 1 \n\t" |
| 224 | "addiu %[irow_t], %[irow_t], 4 \n\t" |
| 225 | "subu %[temp0], %[temp0], %[temp1] \n\t" |
| 226 | "mult %[temp3], %[temp4] \n\t" |
| 227 | "sll %[temp0], %[temp0], 2 \n\t" |
| 228 | "madd %[temp0], %[temp2] \n\t" |
| 229 | "mfhi %[temp5] \n\t" |
| 230 | "sw %[temp1], -4(%[irow_t]) \n\t" |
| 231 | "and %[temp0], %[temp5], %[temp6] \n\t" |
| 232 | "slti %[temp1], %[temp5], 0 \n\t" |
| 233 | "beqz %[temp0], 2f \n\t" |
| 234 | "xor %[temp5], %[temp5], %[temp5] \n\t" |
| 235 | "movz %[temp5], %[temp7], %[temp1] \n\t" |
| 236 | "2: \n\t" |
| 237 | "sb %[temp5], -1(%[dst_t]) \n\t" |
| 238 | "bne %[frow_t], %[loop_end], 1b \n\t" |
| 239 | |
| 240 | : [temp0]"=&r"(temp0), [temp1]"=&r"(temp1), [temp3]"=&r"(temp3), |
| 241 | [temp4]"=&r"(temp4), [temp5]"=&r"(temp5), [temp6]"=&r"(temp6), |
| 242 | [temp7]"=&r"(temp7), [frow_t]"+r"(frow_t), [irow_t]"+r"(irow_t), |
| 243 | [dst_t]"+r"(dst_t), [loop_end]"=&r"(loop_end) |
| 244 | : [temp2]"r"(temp2), [yscale]"r"(yscale), [temp8]"r"(temp8) |
| 245 | : "memory", "hi", "lo" |
| 246 | ); |
| 247 | wrk->y_accum += wrk->y_add; |
| 248 | wrk->dst += wrk->dst_stride; |
| 249 | } else { |
| 250 | ExportRowC(wrk, x_out); |
| 251 | } |
| 252 | } |
| 253 | } |
| 254 | #endif // WEBP_USE_MIPS32 |
| 255 | |
| 256 | //------------------------------------------------------------------------------ |
| 257 | |
| 258 | void WebPRescalerInit(WebPRescaler* const wrk, int src_width, int src_height, |
| 259 | uint8_t* const dst, int dst_width, int dst_height, |
| 260 | int dst_stride, int num_channels, int x_add, int x_sub, |
| 261 | int y_add, int y_sub, int32_t* const work) { |
| 262 | wrk->x_expand = (src_width < dst_width); |
| 263 | wrk->src_width = src_width; |
| 264 | wrk->src_height = src_height; |
| 265 | wrk->dst_width = dst_width; |
| 266 | wrk->dst_height = dst_height; |
| 267 | wrk->dst = dst; |
| 268 | wrk->dst_stride = dst_stride; |
| 269 | wrk->num_channels = num_channels; |
| 270 | // for 'x_expand', we use bilinear interpolation |
| 271 | wrk->x_add = wrk->x_expand ? (x_sub - 1) : x_add - x_sub; |
| 272 | wrk->x_sub = wrk->x_expand ? (x_add - 1) : x_sub; |
| 273 | wrk->y_accum = y_add; |
| 274 | wrk->y_add = y_add; |
| 275 | wrk->y_sub = y_sub; |
| 276 | wrk->fx_scale = (1 << RFIX) / x_sub; |
| 277 | wrk->fy_scale = (1 << RFIX) / y_sub; |
| 278 | wrk->fxy_scale = wrk->x_expand ? |
| 279 | ((int64_t)dst_height << RFIX) / (x_sub * src_height) : |
| 280 | ((int64_t)dst_height << RFIX) / (x_add * src_height); |
| 281 | wrk->irow = work; |
| 282 | wrk->frow = work + num_channels * dst_width; |
| 283 | |
| 284 | if (WebPRescalerImportRow == NULL) { |
| 285 | WebPRescalerImportRow = ImportRowC; |
| 286 | WebPRescalerExportRow = ExportRowC; |
| 287 | if (VP8GetCPUInfo != NULL) { |
| 288 | #if defined(WEBP_USE_MIPS32) |
| 289 | if (VP8GetCPUInfo(kMIPS32)) { |
| 290 | WebPRescalerImportRow = ImportRowMIPS; |
| 291 | WebPRescalerExportRow = ExportRowMIPS; |
| 292 | } |
| 293 | #endif |
| 294 | } |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 295 | } |
| 296 | } |
| 297 | |
| 298 | #undef MULT_FIX |
| 299 | #undef RFIX |
| 300 | |
| 301 | //------------------------------------------------------------------------------ |
| 302 | // all-in-one calls |
| 303 | |
Vikas Arora | 8b72022 | 2014-01-02 16:48:02 -0800 | [diff] [blame] | 304 | int WebPRescaleNeededLines(const WebPRescaler* const wrk, int max_num_lines) { |
| 305 | const int num_lines = (wrk->y_accum + wrk->y_sub - 1) / wrk->y_sub; |
| 306 | return (num_lines > max_num_lines) ? max_num_lines : num_lines; |
| 307 | } |
| 308 | |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 309 | int WebPRescalerImport(WebPRescaler* const wrk, int num_lines, |
| 310 | const uint8_t* src, int src_stride) { |
| 311 | int total_imported = 0; |
| 312 | while (total_imported < num_lines && wrk->y_accum > 0) { |
| 313 | int channel; |
| 314 | for (channel = 0; channel < wrk->num_channels; ++channel) { |
| 315 | WebPRescalerImportRow(wrk, src, channel); |
| 316 | } |
| 317 | src += src_stride; |
| 318 | ++total_imported; |
| 319 | wrk->y_accum -= wrk->y_sub; |
| 320 | } |
| 321 | return total_imported; |
| 322 | } |
| 323 | |
| 324 | int WebPRescalerExport(WebPRescaler* const rescaler) { |
| 325 | int total_exported = 0; |
| 326 | while (WebPRescalerHasPendingOutput(rescaler)) { |
Vikas Arora | af51b94 | 2014-08-28 10:51:12 -0700 | [diff] [blame] | 327 | WebPRescalerExportRow(rescaler, 0); |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 328 | ++total_exported; |
| 329 | } |
| 330 | return total_exported; |
| 331 | } |
| 332 | |
| 333 | //------------------------------------------------------------------------------ |