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