19e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Copyright 2010 Google Inc. All Rights Reserved. 29e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// 39e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Use of this source code is governed by a BSD-style license 49e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// that can be found in the COPYING file in the root of the source 59e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// tree. An additional intellectual property rights grant can be found 69e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// in the file PATENTS. All contributing project authors may 79e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// be found in the AUTHORS file in the root of the source tree. 89e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// ----------------------------------------------------------------------------- 99e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// 109e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Main decoding functions for WebP images. 119e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// 129e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Author: Skal (pascal.massimino@gmail.com) 139e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 149e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern#ifndef WEBP_WEBP_DECODE_H_ 159e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern#define WEBP_WEBP_DECODE_H_ 169e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 179e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern#include "./types.h" 189e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 199e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern#ifdef __cplusplus 209e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zernextern "C" { 219e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern#endif 229e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 237c8da7ce66017295a65ec028084b90800be377f8James Zern#define WEBP_DECODER_ABI_VERSION 0x0208 // MAJOR(8b) + MINOR(8b) 249e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 259e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Note: forward declaring enumerations is not allowed in (strict) C and C++, 269e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// the types are left here for reference. 279e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// typedef enum VP8StatusCode VP8StatusCode; 289e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// typedef enum WEBP_CSP_MODE WEBP_CSP_MODE; 299e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zerntypedef struct WebPRGBABuffer WebPRGBABuffer; 309e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zerntypedef struct WebPYUVABuffer WebPYUVABuffer; 319e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zerntypedef struct WebPDecBuffer WebPDecBuffer; 329e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zerntypedef struct WebPIDecoder WebPIDecoder; 339e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zerntypedef struct WebPBitstreamFeatures WebPBitstreamFeatures; 349e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zerntypedef struct WebPDecoderOptions WebPDecoderOptions; 359e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zerntypedef struct WebPDecoderConfig WebPDecoderConfig; 369e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 379e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Return the decoder's version number, packed in hexadecimal using 8bits for 389e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// each of major/minor/revision. E.g: v2.5.7 is 0x020507. 399e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(int) WebPGetDecoderVersion(void); 409e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 419e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Retrieve basic header information: width, height. 429e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// This function will also validate the header and return 0 in 439e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// case of formatting error. 449e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Pointers 'width' and 'height' can be passed NULL if deemed irrelevant. 459e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(int) WebPGetInfo(const uint8_t* data, size_t data_size, 469e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int* width, int* height); 479e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 489e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Decodes WebP images pointed to by 'data' and returns RGBA samples, along 499e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// with the dimensions in *width and *height. The ordering of samples in 509e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// memory is R, G, B, A, R, G, B, A... in scan order (endian-independent). 517c8da7ce66017295a65ec028084b90800be377f8James Zern// The returned pointer should be deleted calling WebPFree(). 529e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Returns NULL in case of error. 539e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(uint8_t*) WebPDecodeRGBA(const uint8_t* data, size_t data_size, 549e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int* width, int* height); 559e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 569e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Same as WebPDecodeRGBA, but returning A, R, G, B, A, R, G, B... ordered data. 579e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(uint8_t*) WebPDecodeARGB(const uint8_t* data, size_t data_size, 589e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int* width, int* height); 599e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 609e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Same as WebPDecodeRGBA, but returning B, G, R, A, B, G, R, A... ordered data. 619e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(uint8_t*) WebPDecodeBGRA(const uint8_t* data, size_t data_size, 629e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int* width, int* height); 639e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 649e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Same as WebPDecodeRGBA, but returning R, G, B, R, G, B... ordered data. 659e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// If the bitstream contains transparency, it is ignored. 669e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(uint8_t*) WebPDecodeRGB(const uint8_t* data, size_t data_size, 679e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int* width, int* height); 689e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 699e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Same as WebPDecodeRGB, but returning B, G, R, B, G, R... ordered data. 709e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(uint8_t*) WebPDecodeBGR(const uint8_t* data, size_t data_size, 719e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int* width, int* height); 729e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 739e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 749e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Decode WebP images pointed to by 'data' to Y'UV format(*). The pointer 759e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// returned is the Y samples buffer. Upon return, *u and *v will point to 767c8da7ce66017295a65ec028084b90800be377f8James Zern// the U and V chroma data. These U and V buffers need NOT be passed to 777c8da7ce66017295a65ec028084b90800be377f8James Zern// WebPFree(), unlike the returned Y luma one. The dimension of the U and V 787c8da7ce66017295a65ec028084b90800be377f8James Zern// planes are both (*width + 1) / 2 and (*height + 1)/ 2. 799e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Upon return, the Y buffer has a stride returned as '*stride', while U and V 809e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// have a common stride returned as '*uv_stride'. 819e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Return NULL in case of error. 829e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// (*) Also named Y'CbCr. See: http://en.wikipedia.org/wiki/YCbCr 839e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(uint8_t*) WebPDecodeYUV(const uint8_t* data, size_t data_size, 849e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int* width, int* height, 859e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t** u, uint8_t** v, 869e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int* stride, int* uv_stride); 879e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 887c8da7ce66017295a65ec028084b90800be377f8James Zern// Releases memory returned by the WebPDecode*() functions above. 897c8da7ce66017295a65ec028084b90800be377f8James ZernWEBP_EXTERN(void) WebPFree(void* ptr); 907c8da7ce66017295a65ec028084b90800be377f8James Zern 919e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// These five functions are variants of the above ones, that decode the image 929e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// directly into a pre-allocated buffer 'output_buffer'. The maximum storage 939e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// available in this buffer is indicated by 'output_buffer_size'. If this 949e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// storage is not sufficient (or an error occurred), NULL is returned. 959e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Otherwise, output_buffer is returned, for convenience. 969e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// The parameter 'output_stride' specifies the distance (in bytes) 979e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// between scanlines. Hence, output_buffer_size is expected to be at least 989e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// output_stride x picture-height. 999e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(uint8_t*) WebPDecodeRGBAInto( 1009e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern const uint8_t* data, size_t data_size, 1019e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* output_buffer, size_t output_buffer_size, int output_stride); 1029e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(uint8_t*) WebPDecodeARGBInto( 1039e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern const uint8_t* data, size_t data_size, 1049e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* output_buffer, size_t output_buffer_size, int output_stride); 1059e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(uint8_t*) WebPDecodeBGRAInto( 1069e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern const uint8_t* data, size_t data_size, 1079e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* output_buffer, size_t output_buffer_size, int output_stride); 1089e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 1099e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// RGB and BGR variants. Here too the transparency information, if present, 1109e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// will be dropped and ignored. 1119e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(uint8_t*) WebPDecodeRGBInto( 1129e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern const uint8_t* data, size_t data_size, 1139e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* output_buffer, size_t output_buffer_size, int output_stride); 1149e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(uint8_t*) WebPDecodeBGRInto( 1159e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern const uint8_t* data, size_t data_size, 1169e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* output_buffer, size_t output_buffer_size, int output_stride); 1179e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 1189e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// WebPDecodeYUVInto() is a variant of WebPDecodeYUV() that operates directly 1199e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// into pre-allocated luma/chroma plane buffers. This function requires the 1209e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// strides to be passed: one for the luma plane and one for each of the 1219e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// chroma ones. The size of each plane buffer is passed as 'luma_size', 1229e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// 'u_size' and 'v_size' respectively. 1239e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Pointer to the luma plane ('*luma') is returned or NULL if an error occurred 1249e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// during decoding (or because some buffers were found to be too small). 1259e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(uint8_t*) WebPDecodeYUVInto( 1269e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern const uint8_t* data, size_t data_size, 1279e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* luma, size_t luma_size, int luma_stride, 1289e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* u, size_t u_size, int u_stride, 1299e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* v, size_t v_size, int v_stride); 1309e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 1319e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern//------------------------------------------------------------------------------ 1329e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Output colorspaces and buffer 1339e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 1349e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Colorspaces 1359e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Note: the naming describes the byte-ordering of packed samples in memory. 1369e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// For instance, MODE_BGRA relates to samples ordered as B,G,R,A,B,G,R,A,... 1379e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Non-capital names (e.g.:MODE_Argb) relates to pre-multiplied RGB channels. 1389e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// RGBA-4444 and RGB-565 colorspaces are represented by following byte-order: 1399e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// RGBA-4444: [r3 r2 r1 r0 g3 g2 g1 g0], [b3 b2 b1 b0 a3 a2 a1 a0], ... 1409e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// RGB-565: [r4 r3 r2 r1 r0 g5 g4 g3], [g2 g1 g0 b4 b3 b2 b1 b0], ... 1419e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// In the case WEBP_SWAP_16BITS_CSP is defined, the bytes are swapped for 1429e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// these two modes: 1439e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// RGBA-4444: [b3 b2 b1 b0 a3 a2 a1 a0], [r3 r2 r1 r0 g3 g2 g1 g0], ... 1449e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// RGB-565: [g2 g1 g0 b4 b3 b2 b1 b0], [r4 r3 r2 r1 r0 g5 g4 g3], ... 1459e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 1469e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zerntypedef enum WEBP_CSP_MODE { 1479e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern MODE_RGB = 0, MODE_RGBA = 1, 1489e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern MODE_BGR = 2, MODE_BGRA = 3, 1499e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern MODE_ARGB = 4, MODE_RGBA_4444 = 5, 1509e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern MODE_RGB_565 = 6, 1519e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // RGB-premultiplied transparent modes (alpha value is preserved) 1529e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern MODE_rgbA = 7, 1539e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern MODE_bgrA = 8, 1549e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern MODE_Argb = 9, 1559e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern MODE_rgbA_4444 = 10, 1569e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // YUV modes must come after RGB ones. 1579e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern MODE_YUV = 11, MODE_YUVA = 12, // yuv 4:2:0 1589e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern MODE_LAST = 13 1599e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern} WEBP_CSP_MODE; 1609e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 1619e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Some useful macros: 1629e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zernstatic WEBP_INLINE int WebPIsPremultipliedMode(WEBP_CSP_MODE mode) { 1639e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern return (mode == MODE_rgbA || mode == MODE_bgrA || mode == MODE_Argb || 1649e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern mode == MODE_rgbA_4444); 1659e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern} 1669e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 1679e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zernstatic WEBP_INLINE int WebPIsAlphaMode(WEBP_CSP_MODE mode) { 1689e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern return (mode == MODE_RGBA || mode == MODE_BGRA || mode == MODE_ARGB || 1699e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern mode == MODE_RGBA_4444 || mode == MODE_YUVA || 1709e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WebPIsPremultipliedMode(mode)); 1719e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern} 1729e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 1739e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zernstatic WEBP_INLINE int WebPIsRGBMode(WEBP_CSP_MODE mode) { 1749e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern return (mode < MODE_YUV); 1759e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern} 1769e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 1779e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern//------------------------------------------------------------------------------ 1789e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// WebPDecBuffer: Generic structure for describing the output sample buffer. 1799e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 1809e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zernstruct WebPRGBABuffer { // view as RGBA 1819e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* rgba; // pointer to RGBA samples 1829e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int stride; // stride in bytes from one scanline to the next. 1839e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern size_t size; // total size of the *rgba buffer. 1849e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern}; 1859e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 1869e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zernstruct WebPYUVABuffer { // view as YUVA 1879e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* y, *u, *v, *a; // pointer to luma, chroma U/V, alpha samples 1889e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int y_stride; // luma stride 1899e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int u_stride, v_stride; // chroma strides 1909e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int a_stride; // alpha stride 1919e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern size_t y_size; // luma plane size 1929e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern size_t u_size, v_size; // chroma planes size 1939e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern size_t a_size; // alpha-plane size 1949e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern}; 1959e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 1969e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Output buffer 1979e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zernstruct WebPDecBuffer { 1989e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WEBP_CSP_MODE colorspace; // Colorspace. 1999e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int width, height; // Dimensions. 2009e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int is_external_memory; // If true, 'internal_memory' pointer is not used. 2019e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern union { 2029e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WebPRGBABuffer RGBA; 2039e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WebPYUVABuffer YUVA; 2049e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern } u; // Nameless union of buffer parameters. 2059e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint32_t pad[4]; // padding for later use 2069e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 2079e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* private_memory; // Internally allocated memory (only when 2089e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // is_external_memory is false). Should not be used 2099e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // externally, but accessed via the buffer union. 2109e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern}; 2119e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 2129e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Internal, version-checked, entry point 2139e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(int) WebPInitDecBufferInternal(WebPDecBuffer*, int); 2149e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 2159e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Initialize the structure as empty. Must be called before any other use. 2169e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Returns false in case of version mismatch 2179e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zernstatic WEBP_INLINE int WebPInitDecBuffer(WebPDecBuffer* buffer) { 2189e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern return WebPInitDecBufferInternal(buffer, WEBP_DECODER_ABI_VERSION); 2199e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern} 2209e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 2219e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Free any memory associated with the buffer. Must always be called last. 2229e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Note: doesn't free the 'buffer' structure itself. 2239e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(void) WebPFreeDecBuffer(WebPDecBuffer* buffer); 2249e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 2259e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern//------------------------------------------------------------------------------ 2269e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Enumeration of the status codes 2279e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 2289e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zerntypedef enum VP8StatusCode { 2299e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern VP8_STATUS_OK = 0, 2309e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern VP8_STATUS_OUT_OF_MEMORY, 2319e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern VP8_STATUS_INVALID_PARAM, 2329e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern VP8_STATUS_BITSTREAM_ERROR, 2339e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern VP8_STATUS_UNSUPPORTED_FEATURE, 2349e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern VP8_STATUS_SUSPENDED, 2359e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern VP8_STATUS_USER_ABORT, 2369e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern VP8_STATUS_NOT_ENOUGH_DATA 2379e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern} VP8StatusCode; 2389e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 2399e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern//------------------------------------------------------------------------------ 2409e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Incremental decoding 2419e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// 2429e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// This API allows streamlined decoding of partial data. 2439e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Picture can be incrementally decoded as data become available thanks to the 2449e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// WebPIDecoder object. This object can be left in a SUSPENDED state if the 2459e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// picture is only partially decoded, pending additional input. 2469e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Code example: 2479e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// 2489e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// WebPInitDecBuffer(&buffer); 2499e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// buffer.colorspace = mode; 2509e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// ... 2519e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// WebPIDecoder* idec = WebPINewDecoder(&buffer); 2529e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// while (has_more_data) { 2539e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// // ... (get additional data) 2549e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// status = WebPIAppend(idec, new_data, new_data_size); 2559e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// if (status != VP8_STATUS_SUSPENDED || 2569e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// break; 2579e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// } 2589e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// 2599e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// // The above call decodes the current available buffer. 2609e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// // Part of the image can now be refreshed by calling to 2619e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// // WebPIDecGetRGB()/WebPIDecGetYUVA() etc. 2629e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// } 2639e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// WebPIDelete(idec); 2649e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 2659e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Creates a new incremental decoder with the supplied buffer parameter. 2669e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// This output_buffer can be passed NULL, in which case a default output buffer 2679e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// is used (with MODE_RGB). Otherwise, an internal reference to 'output_buffer' 2689e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// is kept, which means that the lifespan of 'output_buffer' must be larger than 2699e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// that of the returned WebPIDecoder object. 2709e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// The supplied 'output_buffer' content MUST NOT be changed between calls to 2719e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// WebPIAppend() or WebPIUpdate() unless 'output_buffer.is_external_memory' is 2729e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// set to 1. In such a case, it is allowed to modify the pointers, size and 2739e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// stride of output_buffer.u.RGBA or output_buffer.u.YUVA, provided they remain 2749e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// within valid bounds. 2759e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// All other fields of WebPDecBuffer MUST remain constant between calls. 2769e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Returns NULL if the allocation failed. 2779e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(WebPIDecoder*) WebPINewDecoder(WebPDecBuffer* output_buffer); 2789e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 2799e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// This function allocates and initializes an incremental-decoder object, which 2809e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// will output the RGB/A samples specified by 'csp' into a preallocated 2819e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// buffer 'output_buffer'. The size of this buffer is at least 2829e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// 'output_buffer_size' and the stride (distance in bytes between two scanlines) 2839e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// is specified by 'output_stride'. 2849e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Additionally, output_buffer can be passed NULL in which case the output 2859e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// buffer will be allocated automatically when the decoding starts. The 2869e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// colorspace 'csp' is taken into account for allocating this buffer. All other 2879e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// parameters are ignored. 2889e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Returns NULL if the allocation failed, or if some parameters are invalid. 2899e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(WebPIDecoder*) WebPINewRGB( 2909e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WEBP_CSP_MODE csp, 2919e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* output_buffer, size_t output_buffer_size, int output_stride); 2929e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 2939e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// This function allocates and initializes an incremental-decoder object, which 2949e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// will output the raw luma/chroma samples into a preallocated planes if 2959e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// supplied. The luma plane is specified by its pointer 'luma', its size 2969e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// 'luma_size' and its stride 'luma_stride'. Similarly, the chroma-u plane 2979e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// is specified by the 'u', 'u_size' and 'u_stride' parameters, and the chroma-v 2989e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// plane by 'v' and 'v_size'. And same for the alpha-plane. The 'a' pointer 2999e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// can be pass NULL in case one is not interested in the transparency plane. 3009e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Conversely, 'luma' can be passed NULL if no preallocated planes are supplied. 3019e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// In this case, the output buffer will be automatically allocated (using 3029e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// MODE_YUVA) when decoding starts. All parameters are then ignored. 3039e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Returns NULL if the allocation failed or if a parameter is invalid. 3049e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(WebPIDecoder*) WebPINewYUVA( 3059e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* luma, size_t luma_size, int luma_stride, 3069e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* u, size_t u_size, int u_stride, 3079e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* v, size_t v_size, int v_stride, 3089e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* a, size_t a_size, int a_stride); 3099e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3109e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Deprecated version of the above, without the alpha plane. 3119e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Kept for backward compatibility. 3129e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(WebPIDecoder*) WebPINewYUV( 3139e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* luma, size_t luma_size, int luma_stride, 3149e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* u, size_t u_size, int u_stride, 3159e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t* v, size_t v_size, int v_stride); 3169e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3179e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Deletes the WebPIDecoder object and associated memory. Must always be called 3189e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// if WebPINewDecoder, WebPINewRGB or WebPINewYUV succeeded. 3199e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(void) WebPIDelete(WebPIDecoder* idec); 3209e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3219e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Copies and decodes the next available data. Returns VP8_STATUS_OK when 3229e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// the image is successfully decoded. Returns VP8_STATUS_SUSPENDED when more 3239e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// data is expected. Returns error in other cases. 3249e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(VP8StatusCode) WebPIAppend( 3259e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WebPIDecoder* idec, const uint8_t* data, size_t data_size); 3269e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3279e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// A variant of the above function to be used when data buffer contains 3289e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// partial data from the beginning. In this case data buffer is not copied 3299e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// to the internal memory. 3309e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Note that the value of the 'data' pointer can change between calls to 3319e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// WebPIUpdate, for instance when the data buffer is resized to fit larger data. 3329e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(VP8StatusCode) WebPIUpdate( 3339e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WebPIDecoder* idec, const uint8_t* data, size_t data_size); 3349e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3359e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Returns the RGB/A image decoded so far. Returns NULL if output params 3369e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// are not initialized yet. The RGB/A output type corresponds to the colorspace 3379e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// specified during call to WebPINewDecoder() or WebPINewRGB(). 3389e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// *last_y is the index of last decoded row in raster scan order. Some pointers 3399e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// (*last_y, *width etc.) can be NULL if corresponding information is not 3409e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// needed. 3419e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(uint8_t*) WebPIDecGetRGB( 3429e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern const WebPIDecoder* idec, int* last_y, 3439e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int* width, int* height, int* stride); 3449e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3459e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Same as above function to get a YUVA image. Returns pointer to the luma 3469e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// plane or NULL in case of error. If there is no alpha information 3479e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// the alpha pointer '*a' will be returned NULL. 3489e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(uint8_t*) WebPIDecGetYUVA( 3499e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern const WebPIDecoder* idec, int* last_y, 3509e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint8_t** u, uint8_t** v, uint8_t** a, 3519e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int* width, int* height, int* stride, int* uv_stride, int* a_stride); 3529e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3539e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Deprecated alpha-less version of WebPIDecGetYUVA(): it will ignore the 3549e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// alpha information (if present). Kept for backward compatibility. 3559e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zernstatic WEBP_INLINE uint8_t* WebPIDecGetYUV( 3569e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern const WebPIDecoder* idec, int* last_y, uint8_t** u, uint8_t** v, 3579e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int* width, int* height, int* stride, int* uv_stride) { 3589e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern return WebPIDecGetYUVA(idec, last_y, u, v, NULL, width, height, 3599e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern stride, uv_stride, NULL); 3609e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern} 3619e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3629e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Generic call to retrieve information about the displayable area. 3639e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// If non NULL, the left/right/width/height pointers are filled with the visible 3649e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// rectangular area so far. 3659e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Returns NULL in case the incremental decoder object is in an invalid state. 3669e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Otherwise returns the pointer to the internal representation. This structure 3679e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// is read-only, tied to WebPIDecoder's lifespan and should not be modified. 3689e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(const WebPDecBuffer*) WebPIDecodedArea( 3699e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern const WebPIDecoder* idec, int* left, int* top, int* width, int* height); 3709e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3719e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern//------------------------------------------------------------------------------ 3729e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Advanced decoding parametrization 3739e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// 3749e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Code sample for using the advanced decoding API 3759e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern/* 3769e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // A) Init a configuration object 3779e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WebPDecoderConfig config; 3789e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern CHECK(WebPInitDecoderConfig(&config)); 3799e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3809e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // B) optional: retrieve the bitstream's features. 3819e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern CHECK(WebPGetFeatures(data, data_size, &config.input) == VP8_STATUS_OK); 3829e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3839e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // C) Adjust 'config', if needed 3849e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern config.no_fancy_upsampling = 1; 3859e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern config.output.colorspace = MODE_BGRA; 3869e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // etc. 3879e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3889e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // Note that you can also make config.output point to an externally 3899e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // supplied memory buffer, provided it's big enough to store the decoded 3909e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // picture. Otherwise, config.output will just be used to allocate memory 3919e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // and store the decoded picture. 3929e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3939e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // D) Decode! 3949e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern CHECK(WebPDecode(data, data_size, &config) == VP8_STATUS_OK); 3959e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3969e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // E) Decoded image is now in config.output (and config.output.u.RGBA) 3979e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 3989e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // F) Reclaim memory allocated in config's object. It's safe to call 3999e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // this function even if the memory is external and wasn't allocated 4009e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // by WebPDecode(). 4019e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WebPFreeDecBuffer(&config.output); 4029e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern*/ 4039e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 4049e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Features gathered from the bitstream 4059e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zernstruct WebPBitstreamFeatures { 4069e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int width; // Width in pixels, as read from the bitstream. 4079e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int height; // Height in pixels, as read from the bitstream. 4089e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int has_alpha; // True if the bitstream contains an alpha channel. 4099e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int has_animation; // True if the bitstream is an animation. 4109e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int format; // 0 = undefined (/mixed), 1 = lossy, 2 = lossless 4119e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 4127c8da7ce66017295a65ec028084b90800be377f8James Zern uint32_t pad[5]; // padding for later use 4139e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern}; 4149e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 4159e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Internal, version-checked, entry point 4169e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(VP8StatusCode) WebPGetFeaturesInternal( 4179e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern const uint8_t*, size_t, WebPBitstreamFeatures*, int); 4189e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 4199e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Retrieve features from the bitstream. The *features structure is filled 4209e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// with information gathered from the bitstream. 4219e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Returns VP8_STATUS_OK when the features are successfully retrieved. Returns 4229e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// VP8_STATUS_NOT_ENOUGH_DATA when more data is needed to retrieve the 4239e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// features from headers. Returns error in other cases. 4249e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zernstatic WEBP_INLINE VP8StatusCode WebPGetFeatures( 4259e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern const uint8_t* data, size_t data_size, 4269e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WebPBitstreamFeatures* features) { 4279e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern return WebPGetFeaturesInternal(data, data_size, features, 4289e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WEBP_DECODER_ABI_VERSION); 4299e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern} 4309e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 4319e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Decoding options 4329e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zernstruct WebPDecoderOptions { 4339e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int bypass_filtering; // if true, skip the in-loop filtering 4349e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int no_fancy_upsampling; // if true, use faster pointwise upsampler 4359e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int use_cropping; // if true, cropping is applied _first_ 4369e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int crop_left, crop_top; // top-left position for cropping. 4379e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern // Will be snapped to even values. 4389e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int crop_width, crop_height; // dimension of the cropping area 4399e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int use_scaling; // if true, scaling is applied _afterward_ 4409e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int scaled_width, scaled_height; // final resolution 4419e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int use_threads; // if true, use multi-threaded decoding 4429e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int dithering_strength; // dithering strength (0=Off, 100=full) 4439e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int flip; // flip output vertically 4449e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern int alpha_dithering_strength; // alpha dithering strength in [0..100] 4459e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 4469e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern uint32_t pad[5]; // padding for later use 4479e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern}; 4489e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 4499e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Main object storing the configuration for advanced decoding. 4509e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zernstruct WebPDecoderConfig { 4519e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WebPBitstreamFeatures input; // Immutable bitstream features (optional) 4529e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WebPDecBuffer output; // Output buffer (can point to external mem) 4539e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WebPDecoderOptions options; // Decoding options 4549e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern}; 4559e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 4569e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Internal, version-checked, entry point 4579e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(int) WebPInitDecoderConfigInternal(WebPDecoderConfig*, int); 4589e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 4599e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Initialize the configuration as empty. This function must always be 4609e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// called first, unless WebPGetFeatures() is to be called. 4619e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Returns false in case of mismatched version. 4629e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zernstatic WEBP_INLINE int WebPInitDecoderConfig(WebPDecoderConfig* config) { 4639e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern return WebPInitDecoderConfigInternal(config, WEBP_DECODER_ABI_VERSION); 4649e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern} 4659e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 4669e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Instantiate a new incremental decoder object with the requested 4679e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// configuration. The bitstream can be passed using 'data' and 'data_size' 4689e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// parameter, in which case the features will be parsed and stored into 4699e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// config->input. Otherwise, 'data' can be NULL and no parsing will occur. 4709e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Note that 'config' can be NULL too, in which case a default configuration 4719e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// is used. 4729e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// The return WebPIDecoder object must always be deleted calling WebPIDelete(). 4739e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Returns NULL in case of error (and config->status will then reflect 4749e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// the error condition). 4759e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(WebPIDecoder*) WebPIDecode(const uint8_t* data, size_t data_size, 4769e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WebPDecoderConfig* config); 4779e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 4789e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// Non-incremental version. This version decodes the full data at once, taking 4799e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// 'config' into account. Returns decoding status (which should be VP8_STATUS_OK 4809e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern// if the decoding was successful). 4819e80ee991168a0a6c2a906dd2c17c5e17df4566eJames ZernWEBP_EXTERN(VP8StatusCode) WebPDecode(const uint8_t* data, size_t data_size, 4829e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern WebPDecoderConfig* config); 4839e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 4849e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern#ifdef __cplusplus 4859e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern} // extern "C" 4869e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern#endif 4879e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern 4889e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern#endif /* WEBP_WEBP_DECODE_H_ */ 489