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 "../webp/config.h"
16#endif
17
18#include "../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