1 // Copyright 2011 Google Inc. All Rights Reserved.
2 //
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.
8 // -----------------------------------------------------------------------------
9 //
10 // Coding tools configuration
11 //
12 // Author: Skal (pascal.massimino@gmail.com)
13
14 #include "../webp/encode.h"
15
16 //------------------------------------------------------------------------------
17 // WebPConfig
18 //------------------------------------------------------------------------------
19
WebPConfigInitInternal(WebPConfig * config,WebPPreset preset,float quality,int version)20 int WebPConfigInitInternal(WebPConfig* config,
21 WebPPreset preset, float quality, int version) {
22 if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_ENCODER_ABI_VERSION)) {
23 return 0; // caller/system version mismatch!
24 }
25 if (config == NULL) return 0;
26
27 config->quality = quality;
28 config->target_size = 0;
29 config->target_PSNR = 0.;
30 config->method = 4;
31 config->sns_strength = 50;
32 config->filter_strength = 60; // mid-filtering
33 config->filter_sharpness = 0;
34 config->filter_type = 1; // default: strong (so U/V is filtered too)
35 config->partitions = 0;
36 config->segments = 4;
37 config->pass = 1;
38 config->show_compressed = 0;
39 config->preprocessing = 0;
40 config->autofilter = 0;
41 config->partition_limit = 0;
42 config->alpha_compression = 1;
43 config->alpha_filtering = 1;
44 config->alpha_quality = 100;
45 config->lossless = 0;
46 config->exact = 0;
47 config->image_hint = WEBP_HINT_DEFAULT;
48 config->emulate_jpeg_size = 0;
49 config->thread_level = 0;
50 config->low_memory = 0;
51 config->near_lossless = 100;
52 #ifdef WEBP_EXPERIMENTAL_FEATURES
53 config->delta_palettization = 0;
54 #endif // WEBP_EXPERIMENTAL_FEATURES
55
56 // TODO(skal): tune.
57 switch (preset) {
58 case WEBP_PRESET_PICTURE:
59 config->sns_strength = 80;
60 config->filter_sharpness = 4;
61 config->filter_strength = 35;
62 config->preprocessing &= ~2; // no dithering
63 break;
64 case WEBP_PRESET_PHOTO:
65 config->sns_strength = 80;
66 config->filter_sharpness = 3;
67 config->filter_strength = 30;
68 config->preprocessing |= 2;
69 break;
70 case WEBP_PRESET_DRAWING:
71 config->sns_strength = 25;
72 config->filter_sharpness = 6;
73 config->filter_strength = 10;
74 break;
75 case WEBP_PRESET_ICON:
76 config->sns_strength = 0;
77 config->filter_strength = 0; // disable filtering to retain sharpness
78 config->preprocessing &= ~2; // no dithering
79 break;
80 case WEBP_PRESET_TEXT:
81 config->sns_strength = 0;
82 config->filter_strength = 0; // disable filtering to retain sharpness
83 config->preprocessing &= ~2; // no dithering
84 config->segments = 2;
85 break;
86 case WEBP_PRESET_DEFAULT:
87 default:
88 break;
89 }
90 return WebPValidateConfig(config);
91 }
92
WebPValidateConfig(const WebPConfig * config)93 int WebPValidateConfig(const WebPConfig* config) {
94 if (config == NULL) return 0;
95 if (config->quality < 0 || config->quality > 100)
96 return 0;
97 if (config->target_size < 0)
98 return 0;
99 if (config->target_PSNR < 0)
100 return 0;
101 if (config->method < 0 || config->method > 6)
102 return 0;
103 if (config->segments < 1 || config->segments > 4)
104 return 0;
105 if (config->sns_strength < 0 || config->sns_strength > 100)
106 return 0;
107 if (config->filter_strength < 0 || config->filter_strength > 100)
108 return 0;
109 if (config->filter_sharpness < 0 || config->filter_sharpness > 7)
110 return 0;
111 if (config->filter_type < 0 || config->filter_type > 1)
112 return 0;
113 if (config->autofilter < 0 || config->autofilter > 1)
114 return 0;
115 if (config->pass < 1 || config->pass > 10)
116 return 0;
117 if (config->show_compressed < 0 || config->show_compressed > 1)
118 return 0;
119 if (config->preprocessing < 0 || config->preprocessing > 7)
120 return 0;
121 if (config->partitions < 0 || config->partitions > 3)
122 return 0;
123 if (config->partition_limit < 0 || config->partition_limit > 100)
124 return 0;
125 if (config->alpha_compression < 0)
126 return 0;
127 if (config->alpha_filtering < 0)
128 return 0;
129 if (config->alpha_quality < 0 || config->alpha_quality > 100)
130 return 0;
131 if (config->lossless < 0 || config->lossless > 1)
132 return 0;
133 if (config->near_lossless < 0 || config->near_lossless > 100)
134 return 0;
135 if (config->image_hint >= WEBP_HINT_LAST)
136 return 0;
137 if (config->emulate_jpeg_size < 0 || config->emulate_jpeg_size > 1)
138 return 0;
139 if (config->thread_level < 0 || config->thread_level > 1)
140 return 0;
141 if (config->low_memory < 0 || config->low_memory > 1)
142 return 0;
143 if (config->exact < 0 || config->exact > 1)
144 return 0;
145 #ifdef WEBP_EXPERIMENTAL_FEATURES
146 if (config->delta_palettization < 0 || config->delta_palettization > 1)
147 return 0;
148 #endif // WEBP_EXPERIMENTAL_FEATURES
149 return 1;
150 }
151
152 //------------------------------------------------------------------------------
153
154 #define MAX_LEVEL 9
155
156 // Mapping between -z level and -m / -q parameter settings.
157 static const struct {
158 uint8_t method_;
159 uint8_t quality_;
160 } kLosslessPresets[MAX_LEVEL + 1] = {
161 { 0, 0 }, { 1, 20 }, { 2, 25 }, { 3, 30 }, { 3, 50 },
162 { 4, 50 }, { 4, 75 }, { 4, 90 }, { 5, 90 }, { 6, 100 }
163 };
164
WebPConfigLosslessPreset(WebPConfig * config,int level)165 int WebPConfigLosslessPreset(WebPConfig* config, int level) {
166 if (config == NULL || level < 0 || level > MAX_LEVEL) return 0;
167 config->lossless = 1;
168 config->method = kLosslessPresets[level].method_;
169 config->quality = kLosslessPresets[level].quality_;
170 return 1;
171 }
172
173 //------------------------------------------------------------------------------
174