| // Copyright 2012 Google Inc. All Rights Reserved. |
| // |
| // Use of this source code is governed by a BSD-style license |
| // that can be found in the COPYING file in the root of the source |
| // tree. An additional intellectual property rights grant can be found |
| // in the file PATENTS. All contributing project authors may |
| // be found in the AUTHORS file in the root of the source tree. |
| // ----------------------------------------------------------------------------- |
| // |
| // Rescaling functions |
| // |
| // Author: Skal (pascal.massimino@gmail.com) |
| |
| #include <assert.h> |
| #include <stdlib.h> |
| #include "./rescaler.h" |
| #include "../dsp/dsp.h" |
| |
| //------------------------------------------------------------------------------ |
| // Implementations of critical functions ImportRow / ExportRow |
| |
| void (*WebPRescalerImportRow)(WebPRescaler* const wrk, |
| const uint8_t* const src, int channel) = NULL; |
| void (*WebPRescalerExportRow)(WebPRescaler* const wrk, int x_out) = NULL; |
| |
| #define RFIX 30 |
| #define MULT_FIX(x, y) (((int64_t)(x) * (y) + (1 << (RFIX - 1))) >> RFIX) |
| |
| static void ImportRowC(WebPRescaler* const wrk, |
| const uint8_t* const src, int channel) { |
| const int x_stride = wrk->num_channels; |
| const int x_out_max = wrk->dst_width * wrk->num_channels; |
| int x_in = channel; |
| int x_out; |
| int accum = 0; |
| if (!wrk->x_expand) { |
| int sum = 0; |
| for (x_out = channel; x_out < x_out_max; x_out += x_stride) { |
| accum += wrk->x_add; |
| for (; accum > 0; accum -= wrk->x_sub) { |
| sum += src[x_in]; |
| x_in += x_stride; |
| } |
| { // Emit next horizontal pixel. |
| const int32_t base = src[x_in]; |
| const int32_t frac = base * (-accum); |
| x_in += x_stride; |
| wrk->frow[x_out] = (sum + base) * wrk->x_sub - frac; |
| // fresh fractional start for next pixel |
| sum = (int)MULT_FIX(frac, wrk->fx_scale); |
| } |
| } |
| } else { // simple bilinear interpolation |
| int left = src[channel], right = src[channel]; |
| for (x_out = channel; x_out < x_out_max; x_out += x_stride) { |
| if (accum < 0) { |
| left = right; |
| x_in += x_stride; |
| right = src[x_in]; |
| accum += wrk->x_add; |
| } |
| wrk->frow[x_out] = right * wrk->x_add + (left - right) * accum; |
| accum -= wrk->x_sub; |
| } |
| } |
| // Accumulate the contribution of the new row. |
| for (x_out = channel; x_out < x_out_max; x_out += x_stride) { |
| wrk->irow[x_out] += wrk->frow[x_out]; |
| } |
| } |
| |
| static void ExportRowC(WebPRescaler* const wrk, int x_out) { |
| if (wrk->y_accum <= 0) { |
| uint8_t* const dst = wrk->dst; |
| int32_t* const irow = wrk->irow; |
| const int32_t* const frow = wrk->frow; |
| const int yscale = wrk->fy_scale * (-wrk->y_accum); |
| const int x_out_max = wrk->dst_width * wrk->num_channels; |
| for (; x_out < x_out_max; ++x_out) { |
| const int frac = (int)MULT_FIX(frow[x_out], yscale); |
| const int v = (int)MULT_FIX(irow[x_out] - frac, wrk->fxy_scale); |
| dst[x_out] = (!(v & ~0xff)) ? v : (v < 0) ? 0 : 255; |
| irow[x_out] = frac; // new fractional start |
| } |
| wrk->y_accum += wrk->y_add; |
| wrk->dst += wrk->dst_stride; |
| } |
| } |
| |
| //------------------------------------------------------------------------------ |
| // MIPS version |
| |
| #if defined(WEBP_USE_MIPS32) |
| |
| static void ImportRowMIPS(WebPRescaler* const wrk, |
| const uint8_t* const src, int channel) { |
| const int x_stride = wrk->num_channels; |
| const int x_out_max = wrk->dst_width * wrk->num_channels; |
| const int fx_scale = wrk->fx_scale; |
| const int x_add = wrk->x_add; |
| const int x_sub = wrk->x_sub; |
| int* frow = wrk->frow + channel; |
| int* irow = wrk->irow + channel; |
| const uint8_t* src1 = src + channel; |
| int temp1, temp2, temp3; |
| int base, frac, sum; |
| int accum, accum1; |
| const int x_stride1 = x_stride << 2; |
| int loop_c = x_out_max - channel; |
| |
| if (!wrk->x_expand) { |
| __asm__ volatile ( |
| "li %[temp1], 0x8000 \n\t" |
| "li %[temp2], 0x10000 \n\t" |
| "li %[sum], 0 \n\t" |
| "li %[accum], 0 \n\t" |
| "1: \n\t" |
| "addu %[accum], %[accum], %[x_add] \n\t" |
| "blez %[accum], 3f \n\t" |
| "2: \n\t" |
| "lbu %[temp3], 0(%[src1]) \n\t" |
| "subu %[accum], %[accum], %[x_sub] \n\t" |
| "addu %[src1], %[src1], %[x_stride] \n\t" |
| "addu %[sum], %[sum], %[temp3] \n\t" |
| "bgtz %[accum], 2b \n\t" |
| "3: \n\t" |
| "lbu %[base], 0(%[src1]) \n\t" |
| "addu %[src1], %[src1], %[x_stride] \n\t" |
| "negu %[accum1], %[accum] \n\t" |
| "mul %[frac], %[base], %[accum1] \n\t" |
| "addu %[temp3], %[sum], %[base] \n\t" |
| "mul %[temp3], %[temp3], %[x_sub] \n\t" |
| "lw %[base], 0(%[irow]) \n\t" |
| "subu %[loop_c], %[loop_c], %[x_stride] \n\t" |
| "sll %[accum1], %[frac], 2 \n\t" |
| "mult %[temp1], %[temp2] \n\t" |
| "madd %[accum1], %[fx_scale] \n\t" |
| "mfhi %[sum] \n\t" |
| "subu %[temp3], %[temp3], %[frac] \n\t" |
| "sw %[temp3], 0(%[frow]) \n\t" |
| "add %[base], %[base], %[temp3] \n\t" |
| "sw %[base], 0(%[irow]) \n\t" |
| "addu %[irow], %[irow], %[x_stride1] \n\t" |
| "addu %[frow], %[frow], %[x_stride1] \n\t" |
| "bgtz %[loop_c], 1b \n\t" |
| |
| : [accum] "=&r" (accum), [src1] "+r" (src1), [temp3] "=&r" (temp3), |
| [sum] "=&r" (sum), [base] "=&r" (base), [frac] "=&r" (frac), |
| [frow] "+r" (frow), [irow] "+r" (irow), [accum1] "=&r" (accum1), |
| [temp2] "=&r" (temp2), [temp1] "=&r" (temp1) |
| : [x_stride] "r" (x_stride), [fx_scale] "r" (fx_scale), |
| [x_sub] "r" (x_sub), [x_add] "r" (x_add), |
| [loop_c] "r" (loop_c), [x_stride1] "r" (x_stride1) |
| : "memory", "hi", "lo" |
| ); |
| } else { |
| __asm__ volatile ( |
| "lbu %[temp1], 0(%[src1]) \n\t" |
| "move %[temp2], %[temp1] \n\t" |
| "li %[accum], 0 \n\t" |
| "1: \n\t" |
| "bgez %[accum], 2f \n\t" |
| "move %[temp2], %[temp1] \n\t" |
| "addu %[src1], %[x_stride] \n\t" |
| "lbu %[temp1], 0(%[src1]) \n\t" |
| "addu %[accum], %[x_add] \n\t" |
| "2: \n\t" |
| "subu %[temp3], %[temp2], %[temp1] \n\t" |
| "mul %[temp3], %[temp3], %[accum] \n\t" |
| "mul %[base], %[temp1], %[x_add] \n\t" |
| "subu %[accum], %[accum], %[x_sub] \n\t" |
| "lw %[frac], 0(%[irow]) \n\t" |
| "subu %[loop_c], %[loop_c], %[x_stride] \n\t" |
| "addu %[temp3], %[base], %[temp3] \n\t" |
| "sw %[temp3], 0(%[frow]) \n\t" |
| "addu %[frow], %[x_stride1] \n\t" |
| "addu %[frac], %[temp3] \n\t" |
| "sw %[frac], 0(%[irow]) \n\t" |
| "addu %[irow], %[x_stride1] \n\t" |
| "bgtz %[loop_c], 1b \n\t" |
| |
| : [src1] "+r" (src1), [accum] "=&r" (accum), [temp1] "=&r" (temp1), |
| [temp2] "=&r" (temp2), [temp3] "=&r" (temp3), [base] "=&r" (base), |
| [frac] "=&r" (frac), [frow] "+r" (frow), [irow] "+r" (irow) |
| : [x_stride] "r" (x_stride), [x_add] "r" (x_add), [x_sub] "r" (x_sub), |
| [x_stride1] "r" (x_stride1), [loop_c] "r" (loop_c) |
| : "memory", "hi", "lo" |
| ); |
| } |
| } |
| |
| static void ExportRowMIPS(WebPRescaler* const wrk, int x_out) { |
| if (wrk->y_accum <= 0) { |
| uint8_t* const dst = wrk->dst; |
| int32_t* const irow = wrk->irow; |
| const int32_t* const frow = wrk->frow; |
| const int yscale = wrk->fy_scale * (-wrk->y_accum); |
| const int x_out_max = wrk->dst_width * wrk->num_channels; |
| // if wrk->fxy_scale can fit into 32 bits use optimized code, |
| // otherwise use C code |
| if ((wrk->fxy_scale >> 32) == 0) { |
| int temp0, temp1, temp3, temp4, temp5, temp6, temp7, loop_end; |
| const int temp2 = (int)(wrk->fxy_scale); |
| const int temp8 = x_out_max << 2; |
| uint8_t* dst_t = (uint8_t*)dst; |
| int32_t* irow_t = (int32_t*)irow; |
| const int32_t* frow_t = (const int32_t*)frow; |
| |
| __asm__ volatile( |
| "addiu %[temp6], $zero, -256 \n\t" |
| "addiu %[temp7], $zero, 255 \n\t" |
| "li %[temp3], 0x10000 \n\t" |
| "li %[temp4], 0x8000 \n\t" |
| "addu %[loop_end], %[frow_t], %[temp8] \n\t" |
| "1: \n\t" |
| "lw %[temp0], 0(%[frow_t]) \n\t" |
| "mult %[temp3], %[temp4] \n\t" |
| "addiu %[frow_t], %[frow_t], 4 \n\t" |
| "sll %[temp0], %[temp0], 2 \n\t" |
| "madd %[temp0], %[yscale] \n\t" |
| "mfhi %[temp1] \n\t" |
| "lw %[temp0], 0(%[irow_t]) \n\t" |
| "addiu %[dst_t], %[dst_t], 1 \n\t" |
| "addiu %[irow_t], %[irow_t], 4 \n\t" |
| "subu %[temp0], %[temp0], %[temp1] \n\t" |
| "mult %[temp3], %[temp4] \n\t" |
| "sll %[temp0], %[temp0], 2 \n\t" |
| "madd %[temp0], %[temp2] \n\t" |
| "mfhi %[temp5] \n\t" |
| "sw %[temp1], -4(%[irow_t]) \n\t" |
| "and %[temp0], %[temp5], %[temp6] \n\t" |
| "slti %[temp1], %[temp5], 0 \n\t" |
| "beqz %[temp0], 2f \n\t" |
| "xor %[temp5], %[temp5], %[temp5] \n\t" |
| "movz %[temp5], %[temp7], %[temp1] \n\t" |
| "2: \n\t" |
| "sb %[temp5], -1(%[dst_t]) \n\t" |
| "bne %[frow_t], %[loop_end], 1b \n\t" |
| |
| : [temp0]"=&r"(temp0), [temp1]"=&r"(temp1), [temp3]"=&r"(temp3), |
| [temp4]"=&r"(temp4), [temp5]"=&r"(temp5), [temp6]"=&r"(temp6), |
| [temp7]"=&r"(temp7), [frow_t]"+r"(frow_t), [irow_t]"+r"(irow_t), |
| [dst_t]"+r"(dst_t), [loop_end]"=&r"(loop_end) |
| : [temp2]"r"(temp2), [yscale]"r"(yscale), [temp8]"r"(temp8) |
| : "memory", "hi", "lo" |
| ); |
| wrk->y_accum += wrk->y_add; |
| wrk->dst += wrk->dst_stride; |
| } else { |
| ExportRowC(wrk, x_out); |
| } |
| } |
| } |
| #endif // WEBP_USE_MIPS32 |
| |
| //------------------------------------------------------------------------------ |
| |
| void WebPRescalerInit(WebPRescaler* const wrk, int src_width, int src_height, |
| uint8_t* const dst, int dst_width, int dst_height, |
| int dst_stride, int num_channels, int x_add, int x_sub, |
| int y_add, int y_sub, int32_t* const work) { |
| wrk->x_expand = (src_width < dst_width); |
| wrk->src_width = src_width; |
| wrk->src_height = src_height; |
| wrk->dst_width = dst_width; |
| wrk->dst_height = dst_height; |
| wrk->dst = dst; |
| wrk->dst_stride = dst_stride; |
| wrk->num_channels = num_channels; |
| // for 'x_expand', we use bilinear interpolation |
| wrk->x_add = wrk->x_expand ? (x_sub - 1) : x_add - x_sub; |
| wrk->x_sub = wrk->x_expand ? (x_add - 1) : x_sub; |
| wrk->y_accum = y_add; |
| wrk->y_add = y_add; |
| wrk->y_sub = y_sub; |
| wrk->fx_scale = (1 << RFIX) / x_sub; |
| wrk->fy_scale = (1 << RFIX) / y_sub; |
| wrk->fxy_scale = wrk->x_expand ? |
| ((int64_t)dst_height << RFIX) / (x_sub * src_height) : |
| ((int64_t)dst_height << RFIX) / (x_add * src_height); |
| wrk->irow = work; |
| wrk->frow = work + num_channels * dst_width; |
| |
| if (WebPRescalerImportRow == NULL) { |
| WebPRescalerImportRow = ImportRowC; |
| WebPRescalerExportRow = ExportRowC; |
| if (VP8GetCPUInfo != NULL) { |
| #if defined(WEBP_USE_MIPS32) |
| if (VP8GetCPUInfo(kMIPS32)) { |
| WebPRescalerImportRow = ImportRowMIPS; |
| WebPRescalerExportRow = ExportRowMIPS; |
| } |
| #endif |
| } |
| } |
| } |
| |
| #undef MULT_FIX |
| #undef RFIX |
| |
| //------------------------------------------------------------------------------ |
| // all-in-one calls |
| |
| int WebPRescaleNeededLines(const WebPRescaler* const wrk, int max_num_lines) { |
| const int num_lines = (wrk->y_accum + wrk->y_sub - 1) / wrk->y_sub; |
| return (num_lines > max_num_lines) ? max_num_lines : num_lines; |
| } |
| |
| int WebPRescalerImport(WebPRescaler* const wrk, int num_lines, |
| const uint8_t* src, int src_stride) { |
| int total_imported = 0; |
| while (total_imported < num_lines && wrk->y_accum > 0) { |
| int channel; |
| for (channel = 0; channel < wrk->num_channels; ++channel) { |
| WebPRescalerImportRow(wrk, src, channel); |
| } |
| src += src_stride; |
| ++total_imported; |
| wrk->y_accum -= wrk->y_sub; |
| } |
| return total_imported; |
| } |
| |
| int WebPRescalerExport(WebPRescaler* const rescaler) { |
| int total_exported = 0; |
| while (WebPRescalerHasPendingOutput(rescaler)) { |
| WebPRescalerExportRow(rescaler, 0); |
| ++total_exported; |
| } |
| return total_exported; |
| } |
| |
| //------------------------------------------------------------------------------ |
