1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
|
// 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 <math.h>
#include <stdlib.h>
#include "./vp8enci.h"
#include "../utils/utils.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 void AccumulateLSIM(const uint8_t* src, int src_stride,
const uint8_t* ref, int ref_stride,
int w, int h, DistoStats* stats) {
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;
}
}
stats->w = w * h;
stats->xm = 0;
stats->ym = 0;
stats->xxm = total_sse;
stats->yym = 0;
stats->xxm = 0;
}
#undef RADIUS
//------------------------------------------------------------------------------
// Distortion
// Max value returned in case of exact similarity.
static const double kMinDistortion_dB = 99.;
static float GetPSNR(const double v) {
return (float)((v > 0.) ? -4.3429448 * log(v / (255 * 255.))
: kMinDistortion_dB);
}
int WebPPictureDistortion(const WebPPicture* src, const WebPPicture* ref,
int type, float result[5]) {
DistoStats stats[5];
int w, h;
memset(stats, 0, sizeof(stats));
if (src == NULL || ref == NULL ||
src->width != ref->width || src->height != ref->height ||
src->use_argb != ref->use_argb || result == NULL) {
return 0;
}
w = src->width;
h = src->height;
if (src->use_argb == 1) {
if (src->argb == NULL || ref->argb == NULL) {
return 0;
} else {
int i, j, c;
uint8_t* tmp1, *tmp2;
uint8_t* const tmp_plane =
(uint8_t*)WebPSafeMalloc(2ULL * w * h, sizeof(*tmp_plane));
if (tmp_plane == NULL) return 0;
tmp1 = tmp_plane;
tmp2 = tmp_plane + w * h;
for (c = 0; c < 4; ++c) {
for (j = 0; j < h; ++j) {
for (i = 0; i < w; ++i) {
tmp1[j * w + i] = src->argb[i + j * src->argb_stride] >> (c * 8);
tmp2[j * w + i] = ref->argb[i + j * ref->argb_stride] >> (c * 8);
}
}
if (type >= 2) {
AccumulateLSIM(tmp1, w, tmp2, w, w, h, &stats[c]);
} else {
VP8SSIMAccumulatePlane(tmp1, w, tmp2, w, w, h, &stats[c]);
}
}
free(tmp_plane);
}
} else {
int has_alpha, uv_w, uv_h;
if (src->y == NULL || ref->y == NULL ||
src->u == NULL || ref->u == NULL ||
src->v == NULL || ref->v == NULL) {
return 0;
}
has_alpha = !!(src->colorspace & WEBP_CSP_ALPHA_BIT);
if (has_alpha != !!(ref->colorspace & WEBP_CSP_ALPHA_BIT) ||
(has_alpha && (src->a == NULL || ref->a == NULL))) {
return 0;
}
uv_w = (src->width + 1) >> 1;
uv_h = (src->height + 1) >> 1;
if (type >= 2) {
AccumulateLSIM(src->y, src->y_stride, ref->y, ref->y_stride,
w, h, &stats[0]);
AccumulateLSIM(src->u, src->uv_stride, ref->u, ref->uv_stride,
uv_w, uv_h, &stats[1]);
AccumulateLSIM(src->v, src->uv_stride, ref->v, ref->uv_stride,
uv_w, uv_h, &stats[2]);
if (has_alpha) {
AccumulateLSIM(src->a, src->a_stride, ref->a, ref->a_stride,
w, h, &stats[3]);
}
} else {
VP8SSIMAccumulatePlane(src->y, src->y_stride,
ref->y, ref->y_stride,
w, h, &stats[0]);
VP8SSIMAccumulatePlane(src->u, src->uv_stride,
ref->u, ref->uv_stride,
uv_w, uv_h, &stats[1]);
VP8SSIMAccumulatePlane(src->v, src->uv_stride,
ref->v, ref->uv_stride,
uv_w, uv_h, &stats[2]);
if (has_alpha) {
VP8SSIMAccumulatePlane(src->a, src->a_stride,
ref->a, ref->a_stride,
w, h, &stats[3]);
}
}
}
// Final stat calculations.
{
int c;
for (c = 0; c <= 4; ++c) {
if (type == 1) {
const double v = VP8SSIMGet(&stats[c]);
result[c] = (float)((v < 1.) ? -10.0 * log10(1. - v)
: kMinDistortion_dB);
} else {
const double v = VP8SSIMGetSquaredError(&stats[c]);
result[c] = GetPSNR(v);
}
// Accumulate forward
if (c < 4) VP8SSIMAddStats(&stats[c], &stats[4]);
}
}
return 1;
}
//------------------------------------------------------------------------------
|