// Copyright 2014 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. // ----------------------------------------------------------------------------- // // WebPPicture tools for measuring distortion // // Author: Skal (pascal.massimino@gmail.com) #include "src/webp/encode.h" #if !(defined(WEBP_DISABLE_STATS) || defined(WEBP_REDUCE_SIZE)) #include #include #include "src/dsp/dsp.h" #include "src/enc/vp8i_enc.h" #include "src/utils/utils.h" typedef double (*AccumulateFunc)(const uint8_t* src, int src_stride, const uint8_t* ref, int ref_stride, int w, int h); //------------------------------------------------------------------------------ // local-min distortion // // For every pixel in the *reference* picture, we search for the local best // match in the compressed image. This is not a symmetrical measure. #define RADIUS 2 // search radius. Shouldn't be too large. static double AccumulateLSIM(const uint8_t* src, int src_stride, const uint8_t* ref, int ref_stride, int w, int h) { int x, y; double total_sse = 0.; for (y = 0; y < h; ++y) { const int y_0 = (y - RADIUS < 0) ? 0 : y - RADIUS; const int y_1 = (y + RADIUS + 1 >= h) ? h : y + RADIUS + 1; for (x = 0; x < w; ++x) { const int x_0 = (x - RADIUS < 0) ? 0 : x - RADIUS; const int x_1 = (x + RADIUS + 1 >= w) ? w : x + RADIUS + 1; double best_sse = 255. * 255.; const double value = (double)ref[y * ref_stride + x]; int i, j; for (j = y_0; j < y_1; ++j) { const uint8_t* const s = src + j * src_stride; for (i = x_0; i < x_1; ++i) { const double diff = s[i] - value; const double sse = diff * diff; if (sse < best_sse) best_sse = sse; } } total_sse += best_sse; } } return total_sse; } #undef RADIUS static double AccumulateSSE(const uint8_t* src, int src_stride, const uint8_t* ref, int ref_stride, int w, int h) { int y; double total_sse = 0.; for (y = 0; y < h; ++y) { total_sse += VP8AccumulateSSE(src, ref, w); src += src_stride; ref += ref_stride; } return total_sse; } //------------------------------------------------------------------------------ static double AccumulateSSIM(const uint8_t* src, int src_stride, const uint8_t* ref, int ref_stride, int w, int h) { const int w0 = (w < VP8_SSIM_KERNEL) ? w : VP8_SSIM_KERNEL; const int w1 = w - VP8_SSIM_KERNEL - 1; const int h0 = (h < VP8_SSIM_KERNEL) ? h : VP8_SSIM_KERNEL; const int h1 = h - VP8_SSIM_KERNEL - 1; int x, y; double sum = 0.; for (y = 0; y < h0; ++y) { for (x = 0; x < w; ++x) { sum += VP8SSIMGetClipped(src, src_stride, ref, ref_stride, x, y, w, h); } } for (; y < h1; ++y) { for (x = 0; x < w0; ++x) { sum += VP8SSIMGetClipped(src, src_stride, ref, ref_stride, x, y, w, h); } for (; x < w1; ++x) { const int off1 = x - VP8_SSIM_KERNEL + (y - VP8_SSIM_KERNEL) * src_stride; const int off2 = x - VP8_SSIM_KERNEL + (y - VP8_SSIM_KERNEL) * ref_stride; sum += VP8SSIMGet(src + off1, src_stride, ref + off2, ref_stride); } for (; x < w; ++x) { sum += VP8SSIMGetClipped(src, src_stride, ref, ref_stride, x, y, w, h); } } for (; y < h; ++y) { for (x = 0; x < w; ++x) { sum += VP8SSIMGetClipped(src, src_stride, ref, ref_stride, x, y, w, h); } } return sum; } //------------------------------------------------------------------------------ // Distortion // Max value returned in case of exact similarity. static const double kMinDistortion_dB = 99.; static double GetPSNR(double v, double size) { return (v > 0. && size > 0.) ? -4.3429448 * log(v / (size * 255 * 255.)) : kMinDistortion_dB; } static double GetLogSSIM(double v, double size) { v = (size > 0.) ? v / size : 1.; return (v < 1.) ? -10.0 * log10(1. - v) : kMinDistortion_dB; } int WebPPlaneDistortion(const uint8_t* src, size_t src_stride, const uint8_t* ref, size_t ref_stride, int width, int height, size_t x_step, int type, float* distortion, float* result) { uint8_t* allocated = NULL; const AccumulateFunc metric = (type == 0) ? AccumulateSSE : (type == 1) ? AccumulateSSIM : AccumulateLSIM; if (src == NULL || ref == NULL || src_stride < x_step * width || ref_stride < x_step * width || result == NULL || distortion == NULL) { return 0; } VP8SSIMDspInit(); if (x_step != 1) { // extract a packed plane if needed int x, y; uint8_t* tmp1; uint8_t* tmp2; allocated = (uint8_t*)WebPSafeMalloc(2ULL * width * height, sizeof(*allocated)); if (allocated == NULL) return 0; tmp1 = allocated; tmp2 = tmp1 + (size_t)width * height; for (y = 0; y < height; ++y) { for (x = 0; x < width; ++x) { tmp1[x + y * width] = src[x * x_step + y * src_stride]; tmp2[x + y * width] = ref[x * x_step + y * ref_stride]; } } src = tmp1; ref = tmp2; } *distortion = (float)metric(src, width, ref, width, width, height); WebPSafeFree(allocated); *result = (type == 1) ? (float)GetLogSSIM(*distortion, (double)width * height) : (float)GetPSNR(*distortion, (double)width * height); return 1; } #ifdef WORDS_BIGENDIAN #define BLUE_OFFSET 3 // uint32_t 0x000000ff is 0x00,00,00,ff in memory #else #define BLUE_OFFSET 0 // uint32_t 0x000000ff is 0xff,00,00,00 in memory #endif int WebPPictureDistortion(const WebPPicture* src, const WebPPicture* ref, int type, float results[5]) { int w, h, c; int ok = 0; WebPPicture p0, p1; double total_size = 0., total_distortion = 0.; if (src == NULL || ref == NULL || src->width != ref->width || src->height != ref->height || results == NULL) { return 0; } VP8SSIMDspInit(); if (!WebPPictureInit(&p0) || !WebPPictureInit(&p1)) return 0; w = src->width; h = src->height; if (!WebPPictureView(src, 0, 0, w, h, &p0)) goto Error; if (!WebPPictureView(ref, 0, 0, w, h, &p1)) goto Error; // We always measure distortion in ARGB space. if (p0.use_argb == 0 && !WebPPictureYUVAToARGB(&p0)) goto Error; if (p1.use_argb == 0 && !WebPPictureYUVAToARGB(&p1)) goto Error; for (c = 0; c < 4; ++c) { float distortion; const size_t stride0 = 4 * (size_t)p0.argb_stride; const size_t stride1 = 4 * (size_t)p1.argb_stride; // results are reported as BGRA const int offset = c ^ BLUE_OFFSET; if (!WebPPlaneDistortion((const uint8_t*)p0.argb + offset, stride0, (const uint8_t*)p1.argb + offset, stride1, w, h, 4, type, &distortion, results + c)) { goto Error; } total_distortion += distortion; total_size += w * h; } results[4] = (type == 1) ? (float)GetLogSSIM(total_distortion, total_size) : (float)GetPSNR(total_distortion, total_size); ok = 1; Error: WebPPictureFree(&p0); WebPPictureFree(&p1); return ok; } #undef BLUE_OFFSET #else // defined(WEBP_DISABLE_STATS) int WebPPlaneDistortion(const uint8_t* src, size_t src_stride, const uint8_t* ref, size_t ref_stride, int width, int height, size_t x_step, int type, float* distortion, float* result) { (void)src; (void)src_stride; (void)ref; (void)ref_stride; (void)width; (void)height; (void)x_step; (void)type; if (distortion == NULL || result == NULL) return 0; *distortion = 0.f; *result = 0.f; return 1; } int WebPPictureDistortion(const WebPPicture* src, const WebPPicture* ref, int type, float results[5]) { int i; (void)src; (void)ref; (void)type; if (results == NULL) return 0; for (i = 0; i < 5; ++i) results[i] = 0.f; return 1; } #endif // !defined(WEBP_DISABLE_STATS)