webp.c revision 9e80ee991168a0a6c2a906dd2c17c5e17df4566e
1a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Copyright 2010 Google Inc. All Rights Reserved. 29aea642eefa7a641ab8b89d953251939221d2719Eric Hassold// 30406ce1417f76f2034833414dcecc9f56253640cVikas Arora// Use of this source code is governed by a BSD-style license 40406ce1417f76f2034833414dcecc9f56253640cVikas Arora// that can be found in the COPYING file in the root of the source 50406ce1417f76f2034833414dcecc9f56253640cVikas Arora// tree. An additional intellectual property rights grant can be found 60406ce1417f76f2034833414dcecc9f56253640cVikas Arora// in the file PATENTS. All contributing project authors may 70406ce1417f76f2034833414dcecc9f56253640cVikas Arora// be found in the AUTHORS file in the root of the source tree. 89aea642eefa7a641ab8b89d953251939221d2719Eric Hassold// ----------------------------------------------------------------------------- 99aea642eefa7a641ab8b89d953251939221d2719Eric Hassold// 109aea642eefa7a641ab8b89d953251939221d2719Eric Hassold// Main decoding functions for WEBP images. 119aea642eefa7a641ab8b89d953251939221d2719Eric Hassold// 129aea642eefa7a641ab8b89d953251939221d2719Eric Hassold// Author: Skal (pascal.massimino@gmail.com) 139aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 149aea642eefa7a641ab8b89d953251939221d2719Eric Hassold#include <stdlib.h> 15a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 16a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#include "./vp8i.h" 17a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#include "./vp8li.h" 18a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#include "./webpi.h" 199e80ee991168a0a6c2a906dd2c17c5e17df4566eJames Zern#include "../webp/mux_types.h" // ALPHA_FLAG 209aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 21a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora//------------------------------------------------------------------------------ 229aea642eefa7a641ab8b89d953251939221d2719Eric Hassold// RIFF layout is: 23a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Offset tag 249aea642eefa7a641ab8b89d953251939221d2719Eric Hassold// 0...3 "RIFF" 4-byte tag 259aea642eefa7a641ab8b89d953251939221d2719Eric Hassold// 4...7 size of image data (including metadata) starting at offset 8 269aea642eefa7a641ab8b89d953251939221d2719Eric Hassold// 8...11 "WEBP" our form-type signature 27a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// The RIFF container (12 bytes) is followed by appropriate chunks: 28a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// 12..15 "VP8 ": 4-bytes tags, signaling the use of VP8 video format 299aea642eefa7a641ab8b89d953251939221d2719Eric Hassold// 16..19 size of the raw VP8 image data, starting at offset 20 309aea642eefa7a641ab8b89d953251939221d2719Eric Hassold// 20.... the VP8 bytes 31a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Or, 32a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// 12..15 "VP8L": 4-bytes tags, signaling the use of VP8L lossless format 33a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// 16..19 size of the raw VP8L image data, starting at offset 20 34a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// 20.... the VP8L bytes 35a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Or, 36a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// 12..15 "VP8X": 4-bytes tags, describing the extended-VP8 chunk. 37a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// 16..19 size of the VP8X chunk starting at offset 20. 38a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// 20..23 VP8X flags bit-map corresponding to the chunk-types present. 39a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// 24..26 Width of the Canvas Image. 40a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// 27..29 Height of the Canvas Image. 411e7bf8805bd030c19924a5306837ecd72c295751Vikas Arora// There can be extra chunks after the "VP8X" chunk (ICCP, FRGM, ANMF, VP8, 421e7bf8805bd030c19924a5306837ecd72c295751Vikas Arora// VP8L, XMP, EXIF ...) 43a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// All sizes are in little-endian order. 44a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Note: chunk data size must be padded to multiple of 2 when written. 45a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 46a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorastatic WEBP_INLINE uint32_t get_le24(const uint8_t* const data) { 47a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return data[0] | (data[1] << 8) | (data[2] << 16); 48a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora} 499aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 50a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorastatic WEBP_INLINE uint32_t get_le32(const uint8_t* const data) { 51a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return (uint32_t)get_le24(data) | (data[3] << 24); 529aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 539aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 54a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Validates the RIFF container (if detected) and skips over it. 5533f74dabbc7920a65ed435d7417987589febdc16Vikas Arora// If a RIFF container is detected, returns: 5633f74dabbc7920a65ed435d7417987589febdc16Vikas Arora// VP8_STATUS_BITSTREAM_ERROR for invalid header, 5733f74dabbc7920a65ed435d7417987589febdc16Vikas Arora// VP8_STATUS_NOT_ENOUGH_DATA for truncated data if have_all_data is true, 5833f74dabbc7920a65ed435d7417987589febdc16Vikas Arora// and VP8_STATUS_OK otherwise. 59a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// In case there are not enough bytes (partial RIFF container), return 0 for 60a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// *riff_size. Else return the RIFF size extracted from the header. 61a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorastatic VP8StatusCode ParseRIFF(const uint8_t** const data, 6233f74dabbc7920a65ed435d7417987589febdc16Vikas Arora size_t* const data_size, int have_all_data, 63a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora size_t* const riff_size) { 64a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(data != NULL); 65a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(data_size != NULL); 66a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(riff_size != NULL); 67a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 68a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *riff_size = 0; // Default: no RIFF present. 69a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (*data_size >= RIFF_HEADER_SIZE && !memcmp(*data, "RIFF", TAG_SIZE)) { 70a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (memcmp(*data + 8, "WEBP", TAG_SIZE)) { 71a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_BITSTREAM_ERROR; // Wrong image file signature. 729aea642eefa7a641ab8b89d953251939221d2719Eric Hassold } else { 73a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora const uint32_t size = get_le32(*data + TAG_SIZE); 74a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Check that we have at least one chunk (i.e "WEBP" + "VP8?nnnn"). 75a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (size < TAG_SIZE + CHUNK_HEADER_SIZE) { 76a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_BITSTREAM_ERROR; 779aea642eefa7a641ab8b89d953251939221d2719Eric Hassold } 78276905dd9bf0cffd7e04c78c95f2c1057275d5bdGeremy Condra if (size > MAX_CHUNK_PAYLOAD) { 79276905dd9bf0cffd7e04c78c95f2c1057275d5bdGeremy Condra return VP8_STATUS_BITSTREAM_ERROR; 80276905dd9bf0cffd7e04c78c95f2c1057275d5bdGeremy Condra } 8133f74dabbc7920a65ed435d7417987589febdc16Vikas Arora if (have_all_data && (size > *data_size - CHUNK_HEADER_SIZE)) { 8233f74dabbc7920a65ed435d7417987589febdc16Vikas Arora return VP8_STATUS_NOT_ENOUGH_DATA; // Truncated bitstream. 8333f74dabbc7920a65ed435d7417987589febdc16Vikas Arora } 8403d5e34c70f174c16282b0efdc6bb9473df5f8f1Vikas Arora // We have a RIFF container. Skip it. 85a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *riff_size = size; 86a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *data += RIFF_HEADER_SIZE; 87a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *data_size -= RIFF_HEADER_SIZE; 88a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 89a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 90a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_OK; 91a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora} 92a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 93a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Validates the VP8X header and skips over it. 94a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Returns VP8_STATUS_BITSTREAM_ERROR for invalid VP8X header, 95a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// VP8_STATUS_NOT_ENOUGH_DATA in case of insufficient data, and 96a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// VP8_STATUS_OK otherwise. 97a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// If a VP8X chunk is found, found_vp8x is set to true and *width_ptr, 98a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// *height_ptr and *flags_ptr are set to the corresponding values extracted 99a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// from the VP8X chunk. 100a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorastatic VP8StatusCode ParseVP8X(const uint8_t** const data, 101a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora size_t* const data_size, 102a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora int* const found_vp8x, 103a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora int* const width_ptr, int* const height_ptr, 104a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint32_t* const flags_ptr) { 105a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora const uint32_t vp8x_size = CHUNK_HEADER_SIZE + VP8X_CHUNK_SIZE; 106a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(data != NULL); 107a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(data_size != NULL); 108a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(found_vp8x != NULL); 109a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 110a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *found_vp8x = 0; 111a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 112a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (*data_size < CHUNK_HEADER_SIZE) { 113a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_NOT_ENOUGH_DATA; // Insufficient data. 114a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 115a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 116a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (!memcmp(*data, "VP8X", TAG_SIZE)) { 117a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora int width, height; 118a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint32_t flags; 119a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora const uint32_t chunk_size = get_le32(*data + TAG_SIZE); 120a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (chunk_size != VP8X_CHUNK_SIZE) { 121a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_BITSTREAM_ERROR; // Wrong chunk size. 122a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 123a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 124a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Verify if enough data is available to validate the VP8X chunk. 125a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (*data_size < vp8x_size) { 126a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_NOT_ENOUGH_DATA; // Insufficient data. 127a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 128a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora flags = get_le32(*data + 8); 129a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora width = 1 + get_le24(*data + 12); 130a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora height = 1 + get_le24(*data + 15); 131a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (width * (uint64_t)height >= MAX_IMAGE_AREA) { 132a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_BITSTREAM_ERROR; // image is too large 133a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 134a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 135a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (flags_ptr != NULL) *flags_ptr = flags; 136a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (width_ptr != NULL) *width_ptr = width; 137a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (height_ptr != NULL) *height_ptr = height; 138a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Skip over VP8X header bytes. 139a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *data += vp8x_size; 140a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *data_size -= vp8x_size; 141a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *found_vp8x = 1; 142a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 143a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_OK; 144a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora} 145a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 146a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Skips to the next VP8/VP8L chunk header in the data given the size of the 147a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// RIFF chunk 'riff_size'. 148a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Returns VP8_STATUS_BITSTREAM_ERROR if any invalid chunk size is encountered, 149a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// VP8_STATUS_NOT_ENOUGH_DATA in case of insufficient data, and 150a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// VP8_STATUS_OK otherwise. 151a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// If an alpha chunk is found, *alpha_data and *alpha_size are set 152a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// appropriately. 153a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorastatic VP8StatusCode ParseOptionalChunks(const uint8_t** const data, 154a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora size_t* const data_size, 155a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora size_t const riff_size, 156a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora const uint8_t** const alpha_data, 157a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora size_t* const alpha_size) { 158a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora const uint8_t* buf; 159a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora size_t buf_size; 160a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint32_t total_size = TAG_SIZE + // "WEBP". 161a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora CHUNK_HEADER_SIZE + // "VP8Xnnnn". 162a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora VP8X_CHUNK_SIZE; // data. 163a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(data != NULL); 164a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(data_size != NULL); 165a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora buf = *data; 166a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora buf_size = *data_size; 167a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 168a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(alpha_data != NULL); 169a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(alpha_size != NULL); 170a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *alpha_data = NULL; 171a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *alpha_size = 0; 172a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 173a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora while (1) { 174a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint32_t chunk_size; 175a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint32_t disk_chunk_size; // chunk_size with padding 176a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 177a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *data = buf; 178a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *data_size = buf_size; 179a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 180a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (buf_size < CHUNK_HEADER_SIZE) { // Insufficient data. 181a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_NOT_ENOUGH_DATA; 182a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 183a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 184a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora chunk_size = get_le32(buf + TAG_SIZE); 185276905dd9bf0cffd7e04c78c95f2c1057275d5bdGeremy Condra if (chunk_size > MAX_CHUNK_PAYLOAD) { 186276905dd9bf0cffd7e04c78c95f2c1057275d5bdGeremy Condra return VP8_STATUS_BITSTREAM_ERROR; // Not a valid chunk size. 187276905dd9bf0cffd7e04c78c95f2c1057275d5bdGeremy Condra } 188a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // For odd-sized chunk-payload, there's one byte padding at the end. 189a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora disk_chunk_size = (CHUNK_HEADER_SIZE + chunk_size + 1) & ~1; 190a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora total_size += disk_chunk_size; 191a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 192a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Check that total bytes skipped so far does not exceed riff_size. 193a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (riff_size > 0 && (total_size > riff_size)) { 194a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_BITSTREAM_ERROR; // Not a valid chunk size. 195a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 196a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 1970406ce1417f76f2034833414dcecc9f56253640cVikas Arora // Start of a (possibly incomplete) VP8/VP8L chunk implies that we have 1980406ce1417f76f2034833414dcecc9f56253640cVikas Arora // parsed all the optional chunks. 1990406ce1417f76f2034833414dcecc9f56253640cVikas Arora // Note: This check must occur before the check 'buf_size < disk_chunk_size' 2000406ce1417f76f2034833414dcecc9f56253640cVikas Arora // below to allow incomplete VP8/VP8L chunks. 2010406ce1417f76f2034833414dcecc9f56253640cVikas Arora if (!memcmp(buf, "VP8 ", TAG_SIZE) || 2020406ce1417f76f2034833414dcecc9f56253640cVikas Arora !memcmp(buf, "VP8L", TAG_SIZE)) { 2030406ce1417f76f2034833414dcecc9f56253640cVikas Arora return VP8_STATUS_OK; 2040406ce1417f76f2034833414dcecc9f56253640cVikas Arora } 2050406ce1417f76f2034833414dcecc9f56253640cVikas Arora 206a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (buf_size < disk_chunk_size) { // Insufficient data. 207a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_NOT_ENOUGH_DATA; 208a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 209a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 210a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (!memcmp(buf, "ALPH", TAG_SIZE)) { // A valid ALPH header. 211a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *alpha_data = buf + CHUNK_HEADER_SIZE; 212a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *alpha_size = chunk_size; 213a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 214a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 215a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // We have a full and valid chunk; skip it. 216a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora buf += disk_chunk_size; 217a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora buf_size -= disk_chunk_size; 218a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 219a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora} 220a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 221a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Validates the VP8/VP8L Header ("VP8 nnnn" or "VP8L nnnn") and skips over it. 222a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Returns VP8_STATUS_BITSTREAM_ERROR for invalid (chunk larger than 223a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// riff_size) VP8/VP8L header, 224a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// VP8_STATUS_NOT_ENOUGH_DATA in case of insufficient data, and 225a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// VP8_STATUS_OK otherwise. 226a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// If a VP8/VP8L chunk is found, *chunk_size is set to the total number of bytes 227a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// extracted from the VP8/VP8L chunk header. 228a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// The flag '*is_lossless' is set to 1 in case of VP8L chunk / raw VP8L data. 229a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorastatic VP8StatusCode ParseVP8Header(const uint8_t** const data_ptr, 23033f74dabbc7920a65ed435d7417987589febdc16Vikas Arora size_t* const data_size, int have_all_data, 23133f74dabbc7920a65ed435d7417987589febdc16Vikas Arora size_t riff_size, size_t* const chunk_size, 232a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora int* const is_lossless) { 233a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora const uint8_t* const data = *data_ptr; 234a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora const int is_vp8 = !memcmp(data, "VP8 ", TAG_SIZE); 235a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora const int is_vp8l = !memcmp(data, "VP8L", TAG_SIZE); 236a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora const uint32_t minimal_size = 237a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora TAG_SIZE + CHUNK_HEADER_SIZE; // "WEBP" + "VP8 nnnn" OR 238a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // "WEBP" + "VP8Lnnnn" 239a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(data != NULL); 240a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(data_size != NULL); 241a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(chunk_size != NULL); 242a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(is_lossless != NULL); 243a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 244a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (*data_size < CHUNK_HEADER_SIZE) { 245a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_NOT_ENOUGH_DATA; // Insufficient data. 246a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 247a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 248a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (is_vp8 || is_vp8l) { 249a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Bitstream contains VP8/VP8L header. 250a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora const uint32_t size = get_le32(data + TAG_SIZE); 251a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if ((riff_size >= minimal_size) && (size > riff_size - minimal_size)) { 252a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_BITSTREAM_ERROR; // Inconsistent size information. 253a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 25433f74dabbc7920a65ed435d7417987589febdc16Vikas Arora if (have_all_data && (size > *data_size - CHUNK_HEADER_SIZE)) { 25533f74dabbc7920a65ed435d7417987589febdc16Vikas Arora return VP8_STATUS_NOT_ENOUGH_DATA; // Truncated bitstream. 25633f74dabbc7920a65ed435d7417987589febdc16Vikas Arora } 257a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Skip over CHUNK_HEADER_SIZE bytes from VP8/VP8L Header. 258a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *chunk_size = size; 259a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *data_ptr += CHUNK_HEADER_SIZE; 260a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *data_size -= CHUNK_HEADER_SIZE; 261a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *is_lossless = is_vp8l; 262a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } else { 263a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Raw VP8/VP8L bitstream (no header). 264a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *is_lossless = VP8LCheckSignature(data, *data_size); 265a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *chunk_size = *data_size; 266a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 267a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 268a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_OK; 269a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora} 270a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 271a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora//------------------------------------------------------------------------------ 272a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 273a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Fetch '*width', '*height', '*has_alpha' and fill out 'headers' based on 274a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// 'data'. All the output parameters may be NULL. If 'headers' is NULL only the 275a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// minimal amount will be read to fetch the remaining parameters. 276a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// If 'headers' is non-NULL this function will attempt to locate both alpha 277a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// data (with or without a VP8X chunk) and the bitstream chunk (VP8/VP8L). 278a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Note: The following chunk sequences (before the raw VP8/VP8L data) are 279a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// considered valid by this function: 280a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// RIFF + VP8(L) 281a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// RIFF + VP8X + (optional chunks) + VP8(L) 282a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// ALPH + VP8 <-- Not a valid WebP format: only allowed for internal purpose. 283a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// VP8(L) <-- Not a valid WebP format: only allowed for internal purpose. 284a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorastatic VP8StatusCode ParseHeadersInternal(const uint8_t* data, 285a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora size_t data_size, 286a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora int* const width, 287a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora int* const height, 288a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora int* const has_alpha, 2890406ce1417f76f2034833414dcecc9f56253640cVikas Arora int* const has_animation, 2908b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora int* const format, 291a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora WebPHeaderStructure* const headers) { 2928b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora int canvas_width = 0; 2938b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora int canvas_height = 0; 2948b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora int image_width = 0; 2958b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora int image_height = 0; 296a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora int found_riff = 0; 297a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora int found_vp8x = 0; 2988b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora int animation_present = 0; 2998b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora int fragments_present = 0; 30033f74dabbc7920a65ed435d7417987589febdc16Vikas Arora const int have_all_data = (headers != NULL) ? headers->have_all_data : 0; 3018b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora 302a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora VP8StatusCode status; 303a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora WebPHeaderStructure hdrs; 304a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 305a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (data == NULL || data_size < RIFF_HEADER_SIZE) { 306a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_NOT_ENOUGH_DATA; 307a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 308a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora memset(&hdrs, 0, sizeof(hdrs)); 309a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora hdrs.data = data; 310a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora hdrs.data_size = data_size; 311a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 312a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Skip over RIFF header. 31333f74dabbc7920a65ed435d7417987589febdc16Vikas Arora status = ParseRIFF(&data, &data_size, have_all_data, &hdrs.riff_size); 314a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (status != VP8_STATUS_OK) { 315a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return status; // Wrong RIFF header / insufficient data. 316a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 317a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora found_riff = (hdrs.riff_size > 0); 318a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 319a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Skip over VP8X. 320a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora { 321a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint32_t flags = 0; 3228b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora status = ParseVP8X(&data, &data_size, &found_vp8x, 3238b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora &canvas_width, &canvas_height, &flags); 324a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (status != VP8_STATUS_OK) { 325a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return status; // Wrong VP8X / insufficient data. 326a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 3278b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora animation_present = !!(flags & ANIMATION_FLAG); 3288b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora fragments_present = !!(flags & FRAGMENTS_FLAG); 329a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (!found_riff && found_vp8x) { 330a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Note: This restriction may be removed in the future, if it becomes 331a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // necessary to send VP8X chunk to the decoder. 332a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_BITSTREAM_ERROR; 333a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 3341e7bf8805bd030c19924a5306837ecd72c295751Vikas Arora if (has_alpha != NULL) *has_alpha = !!(flags & ALPHA_FLAG); 3358b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora if (has_animation != NULL) *has_animation = animation_present; 3368b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora if (format != NULL) *format = 0; // default = undefined 3378b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora 3388b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora image_width = canvas_width; 3398b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora image_height = canvas_height; 3408b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora if (found_vp8x && (animation_present || fragments_present) && 3418b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora headers == NULL) { 3428b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora status = VP8_STATUS_OK; 3438b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora goto ReturnWidthHeight; // Just return features from VP8X header. 344a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 345a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 346a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 3478b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora if (data_size < TAG_SIZE) { 3488b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora status = VP8_STATUS_NOT_ENOUGH_DATA; 3498b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora goto ReturnWidthHeight; 3508b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora } 351a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 352a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Skip over optional chunks if data started with "RIFF + VP8X" or "ALPH". 353a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if ((found_riff && found_vp8x) || 354a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora (!found_riff && !found_vp8x && !memcmp(data, "ALPH", TAG_SIZE))) { 355a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora status = ParseOptionalChunks(&data, &data_size, hdrs.riff_size, 356a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora &hdrs.alpha_data, &hdrs.alpha_data_size); 357a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (status != VP8_STATUS_OK) { 3588b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora goto ReturnWidthHeight; // Invalid chunk size / insufficient data. 359a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 360a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 361a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 362a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Skip over VP8/VP8L header. 36333f74dabbc7920a65ed435d7417987589febdc16Vikas Arora status = ParseVP8Header(&data, &data_size, have_all_data, hdrs.riff_size, 364a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora &hdrs.compressed_size, &hdrs.is_lossless); 365a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (status != VP8_STATUS_OK) { 3668b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora goto ReturnWidthHeight; // Wrong VP8/VP8L chunk-header / insufficient data. 367a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 368a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (hdrs.compressed_size > MAX_CHUNK_PAYLOAD) { 369a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_BITSTREAM_ERROR; 370a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 371a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 3728b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora if (format != NULL && !(animation_present || fragments_present)) { 3738b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora *format = hdrs.is_lossless ? 2 : 1; 3748b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora } 3758b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora 376a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (!hdrs.is_lossless) { 377a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (data_size < VP8_FRAME_HEADER_SIZE) { 3788b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora status = VP8_STATUS_NOT_ENOUGH_DATA; 3798b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora goto ReturnWidthHeight; 380a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 381a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Validates raw VP8 data. 3828b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora if (!VP8GetInfo(data, data_size, (uint32_t)hdrs.compressed_size, 3838b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora &image_width, &image_height)) { 384a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_BITSTREAM_ERROR; 3859aea642eefa7a641ab8b89d953251939221d2719Eric Hassold } 386a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } else { 387a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (data_size < VP8L_FRAME_HEADER_SIZE) { 3888b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora status = VP8_STATUS_NOT_ENOUGH_DATA; 3898b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora goto ReturnWidthHeight; 390a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 391a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Validates raw VP8L data. 3928b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora if (!VP8LGetInfo(data, data_size, &image_width, &image_height, has_alpha)) { 393a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_BITSTREAM_ERROR; 394a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 395a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 3968b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora // Validates image size coherency. 3978b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora if (found_vp8x) { 3988b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora if (canvas_width != image_width || canvas_height != image_height) { 3998b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora return VP8_STATUS_BITSTREAM_ERROR; 4008b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora } 401a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 402a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (headers != NULL) { 403a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *headers = hdrs; 404a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora headers->offset = data - headers->data; 405a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert((uint64_t)(data - headers->data) < MAX_CHUNK_PAYLOAD); 406a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(headers->offset == headers->data_size - data_size); 4079aea642eefa7a641ab8b89d953251939221d2719Eric Hassold } 4088b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora ReturnWidthHeight: 4098b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora if (status == VP8_STATUS_OK || 4108b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora (status == VP8_STATUS_NOT_ENOUGH_DATA && found_vp8x && headers == NULL)) { 4118b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora if (has_alpha != NULL) { 4128b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora // If the data did not contain a VP8X/VP8L chunk the only definitive way 4138b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora // to set this is by looking for alpha data (from an ALPH chunk). 4148b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora *has_alpha |= (hdrs.alpha_data != NULL); 4158b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora } 4168b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora if (width != NULL) *width = image_width; 4178b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora if (height != NULL) *height = image_height; 4188b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora return VP8_STATUS_OK; 4198b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora } else { 4208b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora return status; 4218b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora } 422a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora} 423a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 424a2415724fb3466168b2af5b08bd94ba732c0e753Vikas AroraVP8StatusCode WebPParseHeaders(WebPHeaderStructure* const headers) { 4250406ce1417f76f2034833414dcecc9f56253640cVikas Arora VP8StatusCode status; 4260406ce1417f76f2034833414dcecc9f56253640cVikas Arora int has_animation = 0; 427a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(headers != NULL); 428a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // fill out headers, ignore width/height/has_alpha. 4290406ce1417f76f2034833414dcecc9f56253640cVikas Arora status = ParseHeadersInternal(headers->data, headers->data_size, 4308b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora NULL, NULL, NULL, &has_animation, 4318b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora NULL, headers); 4320406ce1417f76f2034833414dcecc9f56253640cVikas Arora if (status == VP8_STATUS_OK || status == VP8_STATUS_NOT_ENOUGH_DATA) { 4330406ce1417f76f2034833414dcecc9f56253640cVikas Arora // TODO(jzern): full support of animation frames will require API additions. 4340406ce1417f76f2034833414dcecc9f56253640cVikas Arora if (has_animation) { 4350406ce1417f76f2034833414dcecc9f56253640cVikas Arora status = VP8_STATUS_UNSUPPORTED_FEATURE; 4360406ce1417f76f2034833414dcecc9f56253640cVikas Arora } 4370406ce1417f76f2034833414dcecc9f56253640cVikas Arora } 4380406ce1417f76f2034833414dcecc9f56253640cVikas Arora return status; 4399aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 4409aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 441a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora//------------------------------------------------------------------------------ 442466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora// WebPDecParams 44303d5e34c70f174c16282b0efdc6bb9473df5f8f1Vikas Arora 444466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Aroravoid WebPResetDecParams(WebPDecParams* const params) { 4458b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora if (params != NULL) { 446466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora memset(params, 0, sizeof(*params)); 44703d5e34c70f174c16282b0efdc6bb9473df5f8f1Vikas Arora } 44803d5e34c70f174c16282b0efdc6bb9473df5f8f1Vikas Arora} 44903d5e34c70f174c16282b0efdc6bb9473df5f8f1Vikas Arora 450a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora//------------------------------------------------------------------------------ 451466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora// "Into" decoding variants 4529aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 453466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora// Main flow 454a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorastatic VP8StatusCode DecodeInto(const uint8_t* const data, size_t data_size, 455466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPDecParams* const params) { 456a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora VP8StatusCode status; 4579aea642eefa7a641ab8b89d953251939221d2719Eric Hassold VP8Io io; 458a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora WebPHeaderStructure headers; 4599aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 460a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora headers.data = data; 461a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora headers.data_size = data_size; 46233f74dabbc7920a65ed435d7417987589febdc16Vikas Arora headers.have_all_data = 1; 463a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora status = WebPParseHeaders(&headers); // Process Pre-VP8 chunks. 464a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (status != VP8_STATUS_OK) { 465a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return status; 4669aea642eefa7a641ab8b89d953251939221d2719Eric Hassold } 4679aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 468a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(params != NULL); 4699aea642eefa7a641ab8b89d953251939221d2719Eric Hassold VP8InitIo(&io); 470a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io.data = headers.data + headers.offset; 471a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io.data_size = headers.data_size - headers.offset; 472466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPInitCustomIo(params, &io); // Plug the I/O functions. 4739aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 474a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (!headers.is_lossless) { 475a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora VP8Decoder* const dec = VP8New(); 476a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (dec == NULL) { 477a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_OUT_OF_MEMORY; 478a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 479a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora dec->alpha_data_ = headers.alpha_data; 480a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora dec->alpha_data_size_ = headers.alpha_data_size; 481a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 482a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Decode bitstream header, update io->width/io->height. 483a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (!VP8GetHeaders(dec, &io)) { 484a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora status = dec->status_; // An error occurred. Grab error status. 485a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } else { 486a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Allocate/check output buffers. 487a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora status = WebPAllocateDecBuffer(io.width, io.height, params->options, 488a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora params->output); 489a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (status == VP8_STATUS_OK) { // Decode 4908b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora // This change must be done before calling VP8Decode() 4918b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora dec->mt_method_ = VP8GetThreadMethod(params->options, &headers, 4928b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora io.width, io.height); 4938b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora VP8InitDithering(params->options, dec); 494a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (!VP8Decode(dec, &io)) { 495a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora status = dec->status_; 496a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 497a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 498a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 499a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora VP8Delete(dec); 500466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora } else { 501a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora VP8LDecoder* const dec = VP8LNew(); 502a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (dec == NULL) { 503a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_OUT_OF_MEMORY; 504a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 505a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (!VP8LDecodeHeader(dec, &io)) { 506a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora status = dec->status_; // An error occurred. Grab error status. 507a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } else { 508a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Allocate/check output buffers. 509a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora status = WebPAllocateDecBuffer(io.width, io.height, params->options, 510a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora params->output); 511a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (status == VP8_STATUS_OK) { // Decode 512a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (!VP8LDecodeImage(dec)) { 513a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora status = dec->status_; 514a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 515466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora } 516466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora } 517a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora VP8LDelete(dec); 5189aea642eefa7a641ab8b89d953251939221d2719Eric Hassold } 519a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 520466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora if (status != VP8_STATUS_OK) { 521466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPFreeDecBuffer(params->output); 522466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora } 52333f74dabbc7920a65ed435d7417987589febdc16Vikas Arora 52433f74dabbc7920a65ed435d7417987589febdc16Vikas Arora#if WEBP_DECODER_ABI_VERSION > 0x0203 52533f74dabbc7920a65ed435d7417987589febdc16Vikas Arora if (params->options != NULL && params->options->flip) { 52633f74dabbc7920a65ed435d7417987589febdc16Vikas Arora status = WebPFlipBuffer(params->output); 52733f74dabbc7920a65ed435d7417987589febdc16Vikas Arora } 52833f74dabbc7920a65ed435d7417987589febdc16Vikas Arora#endif 529466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return status; 5309aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 5319aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 532466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora// Helpers 533466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arorastatic uint8_t* DecodeIntoRGBABuffer(WEBP_CSP_MODE colorspace, 534a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora const uint8_t* const data, 535a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora size_t data_size, 536a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint8_t* const rgba, 537a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora int stride, size_t size) { 53803d5e34c70f174c16282b0efdc6bb9473df5f8f1Vikas Arora WebPDecParams params; 539466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPDecBuffer buf; 540466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora if (rgba == NULL) { 5419aea642eefa7a641ab8b89d953251939221d2719Eric Hassold return NULL; 5429aea642eefa7a641ab8b89d953251939221d2719Eric Hassold } 543466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPInitDecBuffer(&buf); 544466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPResetDecParams(¶ms); 545466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora params.output = &buf; 546466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora buf.colorspace = colorspace; 547466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora buf.u.RGBA.rgba = rgba; 548466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora buf.u.RGBA.stride = stride; 549466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora buf.u.RGBA.size = size; 550466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora buf.is_external_memory = 1; 551466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora if (DecodeInto(data, data_size, ¶ms) != VP8_STATUS_OK) { 552466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return NULL; 553466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora } 554466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return rgba; 555466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora} 5569aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 557a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorauint8_t* WebPDecodeRGBInto(const uint8_t* data, size_t data_size, 558a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint8_t* output, size_t size, int stride) { 559466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return DecodeIntoRGBABuffer(MODE_RGB, data, data_size, output, stride, size); 5609aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 5619aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 562a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorauint8_t* WebPDecodeRGBAInto(const uint8_t* data, size_t data_size, 563a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint8_t* output, size_t size, int stride) { 564466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return DecodeIntoRGBABuffer(MODE_RGBA, data, data_size, output, stride, size); 565466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora} 5669aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 567a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorauint8_t* WebPDecodeARGBInto(const uint8_t* data, size_t data_size, 568a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint8_t* output, size_t size, int stride) { 569466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return DecodeIntoRGBABuffer(MODE_ARGB, data, data_size, output, stride, size); 5709aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 5719aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 572a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorauint8_t* WebPDecodeBGRInto(const uint8_t* data, size_t data_size, 573a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint8_t* output, size_t size, int stride) { 574466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return DecodeIntoRGBABuffer(MODE_BGR, data, data_size, output, stride, size); 5759aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 5769aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 577a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorauint8_t* WebPDecodeBGRAInto(const uint8_t* data, size_t data_size, 578a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint8_t* output, size_t size, int stride) { 579466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return DecodeIntoRGBABuffer(MODE_BGRA, data, data_size, output, stride, size); 5809aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 5819aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 582a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorauint8_t* WebPDecodeYUVInto(const uint8_t* data, size_t data_size, 583a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint8_t* luma, size_t luma_size, int luma_stride, 584a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint8_t* u, size_t u_size, int u_stride, 585a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora uint8_t* v, size_t v_size, int v_stride) { 58603d5e34c70f174c16282b0efdc6bb9473df5f8f1Vikas Arora WebPDecParams params; 587466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPDecBuffer output; 588466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora if (luma == NULL) return NULL; 589466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPInitDecBuffer(&output); 590466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPResetDecParams(¶ms); 591466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora params.output = &output; 592466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora output.colorspace = MODE_YUV; 593466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora output.u.YUVA.y = luma; 594466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora output.u.YUVA.y_stride = luma_stride; 595466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora output.u.YUVA.y_size = luma_size; 596466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora output.u.YUVA.u = u; 597466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora output.u.YUVA.u_stride = u_stride; 598466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora output.u.YUVA.u_size = u_size; 599466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora output.u.YUVA.v = v; 600466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora output.u.YUVA.v_stride = v_stride; 601466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora output.u.YUVA.v_size = v_size; 602466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora output.is_external_memory = 1; 603466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora if (DecodeInto(data, data_size, ¶ms) != VP8_STATUS_OK) { 6049aea642eefa7a641ab8b89d953251939221d2719Eric Hassold return NULL; 6059aea642eefa7a641ab8b89d953251939221d2719Eric Hassold } 606466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return luma; 6079aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 6089aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 609a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora//------------------------------------------------------------------------------ 6109aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 611a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorastatic uint8_t* Decode(WEBP_CSP_MODE mode, const uint8_t* const data, 612a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora size_t data_size, int* const width, int* const height, 613a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora WebPDecBuffer* const keep_info) { 61403d5e34c70f174c16282b0efdc6bb9473df5f8f1Vikas Arora WebPDecParams params; 615466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPDecBuffer output; 616466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora 617466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPInitDecBuffer(&output); 618466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPResetDecParams(¶ms); 619466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora params.output = &output; 620466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora output.colorspace = mode; 6219aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 622466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora // Retrieve (and report back) the required dimensions from bitstream. 623466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora if (!WebPGetInfo(data, data_size, &output.width, &output.height)) { 6249aea642eefa7a641ab8b89d953251939221d2719Eric Hassold return NULL; 6259aea642eefa7a641ab8b89d953251939221d2719Eric Hassold } 626a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (width != NULL) *width = output.width; 627a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (height != NULL) *height = output.height; 6289aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 629466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora // Decode 630466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora if (DecodeInto(data, data_size, ¶ms) != VP8_STATUS_OK) { 631466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return NULL; 6329aea642eefa7a641ab8b89d953251939221d2719Eric Hassold } 633a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (keep_info != NULL) { // keep track of the side-info 634466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPCopyDecBuffer(&output, keep_info); 6359aea642eefa7a641ab8b89d953251939221d2719Eric Hassold } 636466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora // return decoded samples (don't clear 'output'!) 637a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return WebPIsRGBMode(mode) ? output.u.RGBA.rgba : output.u.YUVA.y; 6389aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 6399aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 640a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorauint8_t* WebPDecodeRGB(const uint8_t* data, size_t data_size, 641466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora int* width, int* height) { 6429aea642eefa7a641ab8b89d953251939221d2719Eric Hassold return Decode(MODE_RGB, data, data_size, width, height, NULL); 6439aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 6449aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 645a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorauint8_t* WebPDecodeRGBA(const uint8_t* data, size_t data_size, 646466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora int* width, int* height) { 6479aea642eefa7a641ab8b89d953251939221d2719Eric Hassold return Decode(MODE_RGBA, data, data_size, width, height, NULL); 6489aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 6499aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 650a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorauint8_t* WebPDecodeARGB(const uint8_t* data, size_t data_size, 651466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora int* width, int* height) { 652466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return Decode(MODE_ARGB, data, data_size, width, height, NULL); 653466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora} 654466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora 655a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorauint8_t* WebPDecodeBGR(const uint8_t* data, size_t data_size, 656466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora int* width, int* height) { 6579aea642eefa7a641ab8b89d953251939221d2719Eric Hassold return Decode(MODE_BGR, data, data_size, width, height, NULL); 6589aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 6599aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 660a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorauint8_t* WebPDecodeBGRA(const uint8_t* data, size_t data_size, 661466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora int* width, int* height) { 6629aea642eefa7a641ab8b89d953251939221d2719Eric Hassold return Decode(MODE_BGRA, data, data_size, width, height, NULL); 6639aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 6649aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 665a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorauint8_t* WebPDecodeYUV(const uint8_t* data, size_t data_size, 666466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora int* width, int* height, uint8_t** u, uint8_t** v, 667466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora int* stride, int* uv_stride) { 668466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPDecBuffer output; // only to preserve the side-infos 6699aea642eefa7a641ab8b89d953251939221d2719Eric Hassold uint8_t* const out = Decode(MODE_YUV, data, data_size, 670466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora width, height, &output); 6719aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 672a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (out != NULL) { 673466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora const WebPYUVABuffer* const buf = &output.u.YUVA; 674466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora *u = buf->u; 675466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora *v = buf->v; 676466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora *stride = buf->y_stride; 677466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora *uv_stride = buf->u_stride; 678466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora assert(buf->u_stride == buf->v_stride); 6799aea642eefa7a641ab8b89d953251939221d2719Eric Hassold } 6809aea642eefa7a641ab8b89d953251939221d2719Eric Hassold return out; 6819aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 6829aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 683466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arorastatic void DefaultFeatures(WebPBitstreamFeatures* const features) { 684a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora assert(features != NULL); 685466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora memset(features, 0, sizeof(*features)); 686466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora} 687466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora 688a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arorastatic VP8StatusCode GetFeatures(const uint8_t* const data, size_t data_size, 689466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPBitstreamFeatures* const features) { 690a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (features == NULL || data == NULL) { 691466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return VP8_STATUS_INVALID_PARAM; 6929aea642eefa7a641ab8b89d953251939221d2719Eric Hassold } 693466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora DefaultFeatures(features); 694a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 6950406ce1417f76f2034833414dcecc9f56253640cVikas Arora // Only parse enough of the data to retrieve the features. 696a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return ParseHeadersInternal(data, data_size, 697a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora &features->width, &features->height, 6980406ce1417f76f2034833414dcecc9f56253640cVikas Arora &features->has_alpha, &features->has_animation, 6998b720228d581a84fd173b6dcb2fa295b59db489aVikas Arora &features->format, NULL); 700a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora} 701a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 702a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora//------------------------------------------------------------------------------ 703a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// WebPGetInfo() 704a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 705a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroraint WebPGetInfo(const uint8_t* data, size_t data_size, 706a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora int* width, int* height) { 707a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora WebPBitstreamFeatures features; 708a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 709a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (GetFeatures(data, data_size, &features) != VP8_STATUS_OK) { 710a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return 0; 711466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora } 712a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 713a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (width != NULL) { 714a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *width = features.width; 715466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora } 716a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (height != NULL) { 717a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora *height = features.height; 718466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora } 719a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 720a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return 1; 721466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora} 7229aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 723a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora//------------------------------------------------------------------------------ 724466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora// Advance decoding API 7259aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 726a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroraint WebPInitDecoderConfigInternal(WebPDecoderConfig* config, 727466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora int version) { 728a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_DECODER_ABI_VERSION)) { 729466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return 0; // version mismatch 730466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora } 731466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora if (config == NULL) { 732466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return 0; 733466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora } 734466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora memset(config, 0, sizeof(*config)); 735466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora DefaultFeatures(&config->input); 736466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPInitDecBuffer(&config->output); 737466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return 1; 738466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora} 7399aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 740a2415724fb3466168b2af5b08bd94ba732c0e753Vikas AroraVP8StatusCode WebPGetFeaturesInternal(const uint8_t* data, size_t data_size, 741a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora WebPBitstreamFeatures* features, 742a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora int version) { 743a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_DECODER_ABI_VERSION)) { 744466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return VP8_STATUS_INVALID_PARAM; // version mismatch 745466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora } 746466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora if (features == NULL) { 747466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return VP8_STATUS_INVALID_PARAM; 748466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora } 7491e7bf8805bd030c19924a5306837ecd72c295751Vikas Arora return GetFeatures(data, data_size, features); 750466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora} 751466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora 752a2415724fb3466168b2af5b08bd94ba732c0e753Vikas AroraVP8StatusCode WebPDecode(const uint8_t* data, size_t data_size, 753a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora WebPDecoderConfig* config) { 754466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPDecParams params; 755466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora VP8StatusCode status; 7569aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 757a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (config == NULL) { 758466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return VP8_STATUS_INVALID_PARAM; 7599aea642eefa7a641ab8b89d953251939221d2719Eric Hassold } 760466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora 761a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora status = GetFeatures(data, data_size, &config->input); 762466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora if (status != VP8_STATUS_OK) { 763a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (status == VP8_STATUS_NOT_ENOUGH_DATA) { 764a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return VP8_STATUS_BITSTREAM_ERROR; // Not-enough-data treated as error. 765a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 766466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return status; 767466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora } 768466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora 769466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora WebPResetDecParams(¶ms); 770466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora params.output = &config->output; 771466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora params.options = &config->options; 772466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora status = DecodeInto(data, data_size, ¶ms); 773466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora 774466727975bcc57c0c5597bcd0747a2fe4777b303Vikas Arora return status; 7759aea642eefa7a641ab8b89d953251939221d2719Eric Hassold} 7769aea642eefa7a641ab8b89d953251939221d2719Eric Hassold 777a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora//------------------------------------------------------------------------------ 778a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Cropping and rescaling. 779a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 780a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroraint WebPIoInitFromOptions(const WebPDecoderOptions* const options, 781a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora VP8Io* const io, WEBP_CSP_MODE src_colorspace) { 782a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora const int W = io->width; 783a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora const int H = io->height; 784a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora int x = 0, y = 0, w = W, h = H; 785a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 786a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Cropping 787a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io->use_cropping = (options != NULL) && (options->use_cropping > 0); 788a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (io->use_cropping) { 789a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora w = options->crop_width; 790a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora h = options->crop_height; 791a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora x = options->crop_left; 792a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora y = options->crop_top; 79333f74dabbc7920a65ed435d7417987589febdc16Vikas Arora if (!WebPIsRGBMode(src_colorspace)) { // only snap for YUV420 794a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora x &= ~1; 79533f74dabbc7920a65ed435d7417987589febdc16Vikas Arora y &= ~1; 796a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 797a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (x < 0 || y < 0 || w <= 0 || h <= 0 || x + w > W || y + h > H) { 798a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return 0; // out of frame boundary error 799a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 800a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 801a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io->crop_left = x; 802a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io->crop_top = y; 803a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io->crop_right = x + w; 804a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io->crop_bottom = y + h; 805a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io->mb_w = w; 806a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io->mb_h = h; 807a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 808a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Scaling 809a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io->use_scaling = (options != NULL) && (options->use_scaling > 0); 810a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (io->use_scaling) { 811a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (options->scaled_width <= 0 || options->scaled_height <= 0) { 812a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return 0; 813a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 814a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io->scaled_width = options->scaled_width; 815a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io->scaled_height = options->scaled_height; 816a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 817a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 818a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Filter 819a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io->bypass_filtering = options && options->bypass_filtering; 820a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 821a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // Fancy upsampler 822a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#ifdef FANCY_UPSAMPLING 823a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io->fancy_upsampling = (options == NULL) || (!options->no_fancy_upsampling); 824a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#endif 825a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 826a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora if (io->use_scaling) { 827a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora // disable filter (only for large downscaling ratio). 828a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io->bypass_filtering = (io->scaled_width < W * 3 / 4) && 829a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora (io->scaled_height < H * 3 / 4); 830a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora io->fancy_upsampling = 0; 831a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora } 832a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora return 1; 833a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora} 834a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 835a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora//------------------------------------------------------------------------------ 836a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 837