SDWebImage资源合集，解决webp格式问题

// Copyright 2011 Google Inc. All Rights Reserved. // // Use of this source code is governed by a BSD-style license // that can be found in the COPYING file in the root of the source // tree. An additional intellectual property rights grant can be found // in the file PATENTS. All contributing project authors may // be found in the AUTHORS file in the root of the source tree. // ----------------------------------------------------------------------------- // // WebP encoder: main interface // // Author: Skal (pascal.massimino@gmail.com) #ifndef WEBP_WEBP_ENCODE_H_ #define WEBP_WEBP_ENCODE_H_ #include "./types.h" #ifdef __cplusplus extern "C" { #endif #define WEBP_ENCODER_ABI_VERSION 0x0209 // MAJOR(8b) + MINOR(8b) // Note: forward declaring enumerations is not allowed in (strict) C and C++, // the types are left here for reference. // typedef enum WebPImageHint WebPImageHint; // typedef enum WebPEncCSP WebPEncCSP; // typedef enum WebPPreset WebPPreset; // typedef enum WebPEncodingError WebPEncodingError; typedef struct WebPConfig WebPConfig; typedef struct WebPPicture WebPPicture; // main structure for I/O typedef struct WebPAuxStats WebPAuxStats; typedef struct WebPMemoryWriter WebPMemoryWriter; // Return the encoder's version number, packed in hexadecimal using 8bits for // each of major/minor/revision. E.g: v2.5.7 is 0x020507. WEBP_EXTERN(int) WebPGetEncoderVersion(void); //------------------------------------------------------------------------------ // One-stop-shop call! No questions asked: // Returns the size of the compressed data (pointed to by *output), or 0 if // an error occurred. The compressed data must be released by the caller // using the call 'WebPFree(*output)'. // These functions compress using the lossy format, and the quality_factor // can go from 0 (smaller output, lower quality) to 100 (best quality, // larger output). WEBP_EXTERN(size_t) WebPEncodeRGB(const uint8_t* rgb, int width, int height, int stride, float quality_factor, uint8_t** output); WEBP_EXTERN(size_t) WebPEncodeBGR(const uint8_t* bgr, int width, int height, int stride, float quality_factor, uint8_t** output); WEBP_EXTERN(size_t) WebPEncodeRGBA(const uint8_t* rgba, int width, int height, int stride, float quality_factor, uint8_t** output); WEBP_EXTERN(size_t) WebPEncodeBGRA(const uint8_t* bgra, int width, int height, int stride, float quality_factor, uint8_t** output); // These functions are the equivalent of the above, but compressing in a // lossless manner. Files are usually larger than lossy format, but will // not suffer any compression loss. WEBP_EXTERN(size_t) WebPEncodeLosslessRGB(const uint8_t* rgb, int width, int height, int stride, uint8_t** output); WEBP_EXTERN(size_t) WebPEncodeLosslessBGR(const uint8_t* bgr, int width, int height, int stride, uint8_t** output); WEBP_EXTERN(size_t) WebPEncodeLosslessRGBA(const uint8_t* rgba, int width, int height, int stride, uint8_t** output); WEBP_EXTERN(size_t) WebPEncodeLosslessBGRA(const uint8_t* bgra, int width, int height, int stride, uint8_t** output); // Releases memory returned by the WebPEncode*() functions above. WEBP_EXTERN(void) WebPFree(void* ptr); //------------------------------------------------------------------------------ // Coding parameters // Image characteristics hint for the underlying encoder. typedef enum WebPImageHint { WEBP_HINT_DEFAULT = 0, // default preset. WEBP_HINT_PICTURE, // digital picture, like portrait, inner shot WEBP_HINT_PHOTO, // outdoor photograph, with natural lighting WEBP_HINT_GRAPH, // Discrete tone image (graph, map-tile etc). WEBP_HINT_LAST } WebPImageHint; // Compression parameters. struct WebPConfig { int lossless; // Lossless encoding (0=lossy(default), 1=lossless). float quality; // between 0 (smallest file) and 100 (biggest) int method; // quality/speed trade-off (0=fast, 6=slower-better) WebPImageHint image_hint; // Hint for image type (lossless only for now). // Parameters related to lossy compression only: int target_size; // if non-zero, set the desired target size in bytes. // Takes precedence over the 'compression' parameter. float target_PSNR; // if non-zero, specifies the minimal distortion to // try to achieve. Takes precedence over target_size. int segments; // maximum number of segments to use, in [1..4] int sns_strength; // Spatial Noise Shaping. 0=off, 100=maximum. int filter_strength; // range: [0 = off .. 100 = strongest] int filter_sharpness; // range: [0 = off .. 7 = least sharp] int filter_type; // filtering type: 0 = simple, 1 = strong (only used // if filter_strength > 0 or autofilter > 0) int autofilter; // Auto adjust filter's strength [0 = off, 1 = on] int alpha_compression; // Algorithm for encoding the alpha plane (0 = none, // 1 = compressed with WebP lossless). Default is 1. int alpha_filtering; // Predictive filtering method for alpha plane. // 0: none, 1: fast, 2: best. Default if 1. int alpha_quality; // Between 0 (smallest size) and 100 (lossless). // Default is 100. int pass; // number of entropy-analysis passes (in [1..10]). int show_compressed; // if true, export the compressed picture back. // In-loop filtering is not applied. int preprocessing; // preprocessing filter: // 0=none, 1=segment-smooth, 2=pseudo-random dithering int partitions; // log2(number of token partitions) in [0..3]. Default // is set to 0 for easier progressive decoding. int partition_limit; // quality degradation allowed to fit the 512k limit // on prediction modes coding (0: no degradation, // 100: maximum possible degradation). int emulate_jpeg_size; // If true, compression parameters will be remapped // to better match the expected output size from // JPEG compression. Generally, the output size will // be similar but the degradation will be lower. int thread_level; // If non-zero, try and use multi-threaded encoding. int low_memory; // If set, reduce memory usage (but increase CPU use). int near_lossless; // Near lossless encoding [0 = off(default) .. 100]. // This feature is experimental. int exact; // if non-zero, preserve the exact RGB values under // transparent area. Otherwise, discard this invisible // RGB information for better compression. The default // value is 0. #ifdef WEBP_EXPERIMENTAL_FEATURES int delta_palettization; uint32_t pad[2]; // padding for later use #else uint32_t pad[3]; // padding for later use #endif // WEBP_EXPERIMENTAL_FEATURES }; // Enumerate some predefined settings for WebPConfig, depending on the type // of source picture. These presets are used when calling WebPConfigPreset(). typedef enum WebPPreset { WEBP_PRESET_DEFAULT = 0, // default preset. WEBP_PRESET_PICTURE,