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 (at) 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 24 int 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 96 int 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. 136 static 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 }; 143 144 int 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
