// Copyright 2015 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. // ----------------------------------------------------------------------------- // #ifndef WEBP_EXTRAS_EXTRAS_H_ #define WEBP_EXTRAS_EXTRAS_H_ #include "webp/types.h" #ifdef __cplusplus extern "C" { #endif #include "sharpyuv/sharpyuv.h" #include "webp/encode.h" #define WEBP_EXTRAS_ABI_VERSION 0x0003 // MAJOR(8b) + MINOR(8b) //------------------------------------------------------------------------------ // Returns the version number of the extras library, packed in hexadecimal using // 8bits for each of major/minor/revision. E.g: v2.5.7 is 0x020507. WEBP_EXTERN int WebPGetExtrasVersion(void); //------------------------------------------------------------------------------ // Ad-hoc colorspace importers. // Import luma sample (gray scale image) into 'picture'. The 'picture' // width and height must be set prior to calling this function. WEBP_EXTERN int WebPImportGray(const uint8_t* gray, WebPPicture* picture); // Import rgb sample in RGB565 packed format into 'picture'. The 'picture' // width and height must be set prior to calling this function. WEBP_EXTERN int WebPImportRGB565(const uint8_t* rgb565, WebPPicture* pic); // Import rgb sample in RGB4444 packed format into 'picture'. The 'picture' // width and height must be set prior to calling this function. WEBP_EXTERN int WebPImportRGB4444(const uint8_t* rgb4444, WebPPicture* pic); // Import a color mapped image. The number of colors is less or equal to // MAX_PALETTE_SIZE. 'pic' must have been initialized. Its content, if any, // will be discarded. Returns 'false' in case of error, or if indexed[] contains // invalid indices. WEBP_EXTERN int WebPImportColorMappedARGB(const uint8_t* indexed, int indexed_stride, const uint32_t palette[], int palette_size, WebPPicture* pic); // Convert the ARGB content of 'pic' from associated to unassociated. // 'pic' can be for instance the result of calling of some WebPPictureImportXXX // functions, with pic->use_argb set to 'true'. It is assumed (and not checked) // that the pre-multiplied r/g/b values as less or equal than the alpha value. // Return false in case of error (invalid parameter, ...). WEBP_EXTERN int WebPUnmultiplyARGB(WebPPicture* pic); //------------------------------------------------------------------------------ // Parse a bitstream, search for VP8 (lossy) header and report a // rough estimation of the quality factor used for compressing the bitstream. // If the bitstream is in lossless format, the special value '101' is returned. // Otherwise (lossy bitstream), the returned value is in the range [0..100]. // Any error (invalid bitstream, animated WebP, incomplete header, etc.) // will return a value of -1. WEBP_EXTERN int VP8EstimateQuality(const uint8_t* const data, size_t size); //------------------------------------------------------------------------------ // Computes a score between 0 and 100 which represents the risk of having visual // quality loss from converting an RGB image to YUV420. // A low score, typically < 40, means there is a low risk of artifacts from // chroma subsampling and a simple averaging algorithm can be used instead of // the more expensive SharpYuvConvert function. // A medium score, typically >= 40 and < 70, means that simple chroma // subsampling will produce artifacts and it may be advisable to use the more // costly SharpYuvConvert for YUV420 conversion. // A high score, typically >= 70, means there is a very high risk of artifacts // from chroma subsampling even with SharpYuvConvert, and best results might be // achieved by using YUV444. // If not using SharpYuvConvert, a threshold of about 50 can be used to decide // between (simple averaging) 420 and 444. // r_ptr, g_ptr, b_ptr: pointers to the source r, g and b channels. Should point // to uint8_t buffers if rgb_bit_depth is 8, or uint16_t buffers otherwise. // rgb_step: distance in bytes between two horizontally adjacent pixels on the // r, g and b channels. If rgb_bit_depth is > 8, it should be a // multiple of 2. // rgb_stride: distance in bytes between two vertically adjacent pixels on the // r, g, and b channels. If rgb_bit_depth is > 8, it should be a // multiple of 2. // rgb_bit_depth: number of bits for each r/g/b value. Only a value of 8 is // currently supported. // width, height: width and height of the image in pixels // Returns 0 on failure. WEBP_EXTERN int SharpYuvEstimate420Risk( const void* r_ptr, const void* g_ptr, const void* b_ptr, int rgb_step, int rgb_stride, int rgb_bit_depth, int width, int height, const SharpYuvOptions* options, float* score); //------------------------------------------------------------------------------ #ifdef __cplusplus } // extern "C" #endif #endif // WEBP_EXTRAS_EXTRAS_H_