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#if defined(__cplusplus) || defined(c_plusplus)
17extern "C" {
18#endif
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;   // rather high filtering, helps w/ gradients.
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->image_hint = WEBP_HINT_DEFAULT;
51  config->emulate_jpeg_size = 0;
52  config->thread_level = 0;
53  config->low_memory = 0;
54
55  // TODO(skal): tune.
56  switch (preset) {
57    case WEBP_PRESET_PICTURE:
58      config->sns_strength = 80;
59      config->filter_sharpness = 4;
60      config->filter_strength = 35;
61      break;
62    case WEBP_PRESET_PHOTO:
63      config->sns_strength = 80;
64      config->filter_sharpness = 3;
65      config->filter_strength = 30;
66      break;
67    case WEBP_PRESET_DRAWING:
68      config->sns_strength = 25;
69      config->filter_sharpness = 6;
70      config->filter_strength = 10;
71      break;
72    case WEBP_PRESET_ICON:
73      config->sns_strength = 0;
74      config->filter_strength = 0;   // disable filtering to retain sharpness
75      break;
76    case WEBP_PRESET_TEXT:
77      config->sns_strength = 0;
78      config->filter_strength = 0;   // disable filtering to retain sharpness
79      config->segments = 2;
80      break;
81    case WEBP_PRESET_DEFAULT:
82    default:
83      break;
84  }
85  return WebPValidateConfig(config);
86}
87
88int WebPValidateConfig(const WebPConfig* config) {
89  if (config == NULL) return 0;
90  if (config->quality < 0 || config->quality > 100)
91    return 0;
92  if (config->target_size < 0)
93    return 0;
94  if (config->target_PSNR < 0)
95    return 0;
96  if (config->method < 0 || config->method > 6)
97    return 0;
98  if (config->segments < 1 || config->segments > 4)
99    return 0;
100  if (config->sns_strength < 0 || config->sns_strength > 100)
101    return 0;
102  if (config->filter_strength < 0 || config->filter_strength > 100)
103    return 0;
104  if (config->filter_sharpness < 0 || config->filter_sharpness > 7)
105    return 0;
106  if (config->filter_type < 0 || config->filter_type > 1)
107    return 0;
108  if (config->autofilter < 0 || config->autofilter > 1)
109    return 0;
110  if (config->pass < 1 || config->pass > 10)
111    return 0;
112  if (config->show_compressed < 0 || config->show_compressed > 1)
113    return 0;
114  if (config->preprocessing < 0 || config->preprocessing > 1)
115    return 0;
116  if (config->partitions < 0 || config->partitions > 3)
117    return 0;
118  if (config->partition_limit < 0 || config->partition_limit > 100)
119    return 0;
120  if (config->alpha_compression < 0)
121    return 0;
122  if (config->alpha_filtering < 0)
123    return 0;
124  if (config->alpha_quality < 0 || config->alpha_quality > 100)
125    return 0;
126  if (config->lossless < 0 || config->lossless > 1)
127    return 0;
128  if (config->image_hint >= WEBP_HINT_LAST)
129    return 0;
130  if (config->emulate_jpeg_size < 0 || config->emulate_jpeg_size > 1)
131    return 0;
132  if (config->thread_level < 0 || config->thread_level > 1)
133    return 0;
134  if (config->low_memory < 0 || config->low_memory > 1)
135    return 0;
136  return 1;
137}
138
139//------------------------------------------------------------------------------
140
141#if defined(__cplusplus) || defined(c_plusplus)
142}    // extern "C"
143#endif
144