540 lines
18 KiB
C
540 lines
18 KiB
C
// Copyright 2011 Google Inc. All Rights Reserved.
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//
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// Use of this source code is governed by a BSD-style license
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// that can be found in the COPYING file in the root of the source
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// tree. An additional intellectual property rights grant can be found
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// in the file PATENTS. All contributing project authors may
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// be found in the AUTHORS file in the root of the source tree.
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// -----------------------------------------------------------------------------
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//
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// Read APIs for mux.
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//
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// Authors: Urvang (urvang@google.com)
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// Vikas (vikasa@google.com)
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#include <assert.h>
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#include "./muxi.h"
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#include "../utils/utils.h"
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//------------------------------------------------------------------------------
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// Helper method(s).
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// Handy MACRO.
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#define SWITCH_ID_LIST(INDEX, LIST) \
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if (idx == (INDEX)) { \
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const WebPChunk* const chunk = ChunkSearchList((LIST), nth, \
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kChunks[(INDEX)].tag); \
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if (chunk) { \
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*data = chunk->data_; \
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return WEBP_MUX_OK; \
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} else { \
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return WEBP_MUX_NOT_FOUND; \
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} \
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}
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static WebPMuxError MuxGet(const WebPMux* const mux, CHUNK_INDEX idx,
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uint32_t nth, WebPData* const data) {
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assert(mux != NULL);
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assert(!IsWPI(kChunks[idx].id));
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WebPDataInit(data);
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SWITCH_ID_LIST(IDX_VP8X, mux->vp8x_);
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SWITCH_ID_LIST(IDX_ICCP, mux->iccp_);
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SWITCH_ID_LIST(IDX_ANIM, mux->anim_);
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SWITCH_ID_LIST(IDX_EXIF, mux->exif_);
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SWITCH_ID_LIST(IDX_XMP, mux->xmp_);
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SWITCH_ID_LIST(IDX_UNKNOWN, mux->unknown_);
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return WEBP_MUX_NOT_FOUND;
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}
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#undef SWITCH_ID_LIST
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// Fill the chunk with the given data (includes chunk header bytes), after some
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// verifications.
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static WebPMuxError ChunkVerifyAndAssign(WebPChunk* chunk,
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const uint8_t* data, size_t data_size,
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size_t riff_size, int copy_data) {
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uint32_t chunk_size;
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WebPData chunk_data;
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// Sanity checks.
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if (data_size < TAG_SIZE) return WEBP_MUX_NOT_ENOUGH_DATA;
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chunk_size = GetLE32(data + TAG_SIZE);
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{
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const size_t chunk_disk_size = SizeWithPadding(chunk_size);
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if (chunk_disk_size > riff_size) return WEBP_MUX_BAD_DATA;
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if (chunk_disk_size > data_size) return WEBP_MUX_NOT_ENOUGH_DATA;
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}
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// Data assignment.
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chunk_data.bytes = data + CHUNK_HEADER_SIZE;
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chunk_data.size = chunk_size;
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return ChunkAssignData(chunk, &chunk_data, copy_data, GetLE32(data + 0));
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}
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int MuxImageFinalize(WebPMuxImage* const wpi) {
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const WebPChunk* const img = wpi->img_;
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const WebPData* const image = &img->data_;
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const int is_lossless = (img->tag_ == kChunks[IDX_VP8L].tag);
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int w, h;
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int vp8l_has_alpha = 0;
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const int ok = is_lossless ?
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VP8LGetInfo(image->bytes, image->size, &w, &h, &vp8l_has_alpha) :
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VP8GetInfo(image->bytes, image->size, image->size, &w, &h);
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assert(img != NULL);
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if (ok) {
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// Ignore ALPH chunk accompanying VP8L.
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if (is_lossless && (wpi->alpha_ != NULL)) {
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ChunkDelete(wpi->alpha_);
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wpi->alpha_ = NULL;
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}
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wpi->width_ = w;
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wpi->height_ = h;
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wpi->has_alpha_ = vp8l_has_alpha || (wpi->alpha_ != NULL);
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}
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return ok;
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}
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static int MuxImageParse(const WebPChunk* const chunk, int copy_data,
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WebPMuxImage* const wpi) {
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const uint8_t* bytes = chunk->data_.bytes;
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size_t size = chunk->data_.size;
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const uint8_t* const last = bytes + size;
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WebPChunk subchunk;
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size_t subchunk_size;
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ChunkInit(&subchunk);
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assert(chunk->tag_ == kChunks[IDX_ANMF].tag ||
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chunk->tag_ == kChunks[IDX_FRGM].tag);
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assert(!wpi->is_partial_);
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// ANMF/FRGM.
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{
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const size_t hdr_size = (chunk->tag_ == kChunks[IDX_ANMF].tag) ?
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ANMF_CHUNK_SIZE : FRGM_CHUNK_SIZE;
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const WebPData temp = { bytes, hdr_size };
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// Each of ANMF and FRGM chunk contain a header at the beginning. So, its
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// size should at least be 'hdr_size'.
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if (size < hdr_size) goto Fail;
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ChunkAssignData(&subchunk, &temp, copy_data, chunk->tag_);
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}
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ChunkSetNth(&subchunk, &wpi->header_, 1);
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wpi->is_partial_ = 1; // Waiting for ALPH and/or VP8/VP8L chunks.
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// Rest of the chunks.
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subchunk_size = ChunkDiskSize(&subchunk) - CHUNK_HEADER_SIZE;
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bytes += subchunk_size;
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size -= subchunk_size;
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while (bytes != last) {
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ChunkInit(&subchunk);
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if (ChunkVerifyAndAssign(&subchunk, bytes, size, size,
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copy_data) != WEBP_MUX_OK) {
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goto Fail;
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}
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switch (ChunkGetIdFromTag(subchunk.tag_)) {
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case WEBP_CHUNK_ALPHA:
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if (wpi->alpha_ != NULL) goto Fail; // Consecutive ALPH chunks.
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if (ChunkSetNth(&subchunk, &wpi->alpha_, 1) != WEBP_MUX_OK) goto Fail;
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wpi->is_partial_ = 1; // Waiting for a VP8 chunk.
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break;
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case WEBP_CHUNK_IMAGE:
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if (ChunkSetNth(&subchunk, &wpi->img_, 1) != WEBP_MUX_OK) goto Fail;
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if (!MuxImageFinalize(wpi)) goto Fail;
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wpi->is_partial_ = 0; // wpi is completely filled.
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break;
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case WEBP_CHUNK_UNKNOWN:
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if (wpi->is_partial_) goto Fail; // Encountered an unknown chunk
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// before some image chunks.
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if (ChunkSetNth(&subchunk, &wpi->unknown_, 0) != WEBP_MUX_OK) goto Fail;
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break;
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default:
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goto Fail;
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break;
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}
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subchunk_size = ChunkDiskSize(&subchunk);
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bytes += subchunk_size;
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size -= subchunk_size;
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}
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if (wpi->is_partial_) goto Fail;
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return 1;
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Fail:
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ChunkRelease(&subchunk);
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return 0;
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}
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//------------------------------------------------------------------------------
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// Create a mux object from WebP-RIFF data.
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WebPMux* WebPMuxCreateInternal(const WebPData* bitstream, int copy_data,
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int version) {
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size_t riff_size;
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uint32_t tag;
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const uint8_t* end;
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WebPMux* mux = NULL;
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WebPMuxImage* wpi = NULL;
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const uint8_t* data;
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size_t size;
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WebPChunk chunk;
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ChunkInit(&chunk);
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// Sanity checks.
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if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_MUX_ABI_VERSION)) {
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return NULL; // version mismatch
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}
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if (bitstream == NULL) return NULL;
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data = bitstream->bytes;
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size = bitstream->size;
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if (data == NULL) return NULL;
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if (size < RIFF_HEADER_SIZE) return NULL;
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if (GetLE32(data + 0) != MKFOURCC('R', 'I', 'F', 'F') ||
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GetLE32(data + CHUNK_HEADER_SIZE) != MKFOURCC('W', 'E', 'B', 'P')) {
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return NULL;
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}
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mux = WebPMuxNew();
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if (mux == NULL) return NULL;
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if (size < RIFF_HEADER_SIZE + TAG_SIZE) goto Err;
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tag = GetLE32(data + RIFF_HEADER_SIZE);
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if (tag != kChunks[IDX_VP8].tag &&
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tag != kChunks[IDX_VP8L].tag &&
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tag != kChunks[IDX_VP8X].tag) {
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goto Err; // First chunk should be VP8, VP8L or VP8X.
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}
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riff_size = SizeWithPadding(GetLE32(data + TAG_SIZE));
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if (riff_size > MAX_CHUNK_PAYLOAD || riff_size > size) {
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goto Err;
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} else {
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if (riff_size < size) { // Redundant data after last chunk.
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size = riff_size; // To make sure we don't read any data beyond mux_size.
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}
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}
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end = data + size;
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data += RIFF_HEADER_SIZE;
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size -= RIFF_HEADER_SIZE;
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wpi = (WebPMuxImage*)malloc(sizeof(*wpi));
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if (wpi == NULL) goto Err;
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MuxImageInit(wpi);
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// Loop over chunks.
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while (data != end) {
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size_t data_size;
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WebPChunkId id;
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WebPChunk** chunk_list;
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if (ChunkVerifyAndAssign(&chunk, data, size, riff_size,
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copy_data) != WEBP_MUX_OK) {
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goto Err;
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}
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data_size = ChunkDiskSize(&chunk);
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id = ChunkGetIdFromTag(chunk.tag_);
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switch (id) {
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case WEBP_CHUNK_ALPHA:
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if (wpi->alpha_ != NULL) goto Err; // Consecutive ALPH chunks.
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if (ChunkSetNth(&chunk, &wpi->alpha_, 1) != WEBP_MUX_OK) goto Err;
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wpi->is_partial_ = 1; // Waiting for a VP8 chunk.
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break;
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case WEBP_CHUNK_IMAGE:
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if (ChunkSetNth(&chunk, &wpi->img_, 1) != WEBP_MUX_OK) goto Err;
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if (!MuxImageFinalize(wpi)) goto Err;
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wpi->is_partial_ = 0; // wpi is completely filled.
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PushImage:
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// Add this to mux->images_ list.
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if (MuxImagePush(wpi, &mux->images_) != WEBP_MUX_OK) goto Err;
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MuxImageInit(wpi); // Reset for reading next image.
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break;
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case WEBP_CHUNK_ANMF:
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#ifdef WEBP_EXPERIMENTAL_FEATURES
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case WEBP_CHUNK_FRGM:
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#endif
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if (wpi->is_partial_) goto Err; // Previous wpi is still incomplete.
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if (!MuxImageParse(&chunk, copy_data, wpi)) goto Err;
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ChunkRelease(&chunk);
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goto PushImage;
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break;
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default: // A non-image chunk.
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if (wpi->is_partial_) goto Err; // Encountered a non-image chunk before
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// getting all chunks of an image.
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chunk_list = MuxGetChunkListFromId(mux, id); // List to add this chunk.
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if (ChunkSetNth(&chunk, chunk_list, 0) != WEBP_MUX_OK) goto Err;
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break;
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}
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data += data_size;
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size -= data_size;
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ChunkInit(&chunk);
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}
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// Validate mux if complete.
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if (MuxValidate(mux) != WEBP_MUX_OK) goto Err;
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MuxImageDelete(wpi);
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return mux; // All OK;
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Err: // Something bad happened.
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ChunkRelease(&chunk);
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MuxImageDelete(wpi);
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WebPMuxDelete(mux);
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return NULL;
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}
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//------------------------------------------------------------------------------
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// Get API(s).
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// Validates that the given mux has a single image.
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static WebPMuxError ValidateForSingleImage(const WebPMux* const mux) {
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const int num_images = MuxImageCount(mux->images_, WEBP_CHUNK_IMAGE);
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const int num_frames = MuxImageCount(mux->images_, WEBP_CHUNK_ANMF);
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const int num_fragments = MuxImageCount(mux->images_, WEBP_CHUNK_FRGM);
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if (num_images == 0) {
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// No images in mux.
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return WEBP_MUX_NOT_FOUND;
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} else if (num_images == 1 && num_frames == 0 && num_fragments == 0) {
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// Valid case (single image).
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return WEBP_MUX_OK;
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} else {
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// Frame/Fragment case OR an invalid mux.
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return WEBP_MUX_INVALID_ARGUMENT;
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}
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}
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// Get the canvas width, height and flags after validating that VP8X/VP8/VP8L
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// chunk and canvas size are valid.
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static WebPMuxError MuxGetCanvasInfo(const WebPMux* const mux,
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int* width, int* height, uint32_t* flags) {
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int w, h;
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uint32_t f = 0;
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WebPData data;
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assert(mux != NULL);
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// Check if VP8X chunk is present.
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if (MuxGet(mux, IDX_VP8X, 1, &data) == WEBP_MUX_OK) {
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if (data.size < VP8X_CHUNK_SIZE) return WEBP_MUX_BAD_DATA;
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f = GetLE32(data.bytes + 0);
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w = GetLE24(data.bytes + 4) + 1;
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h = GetLE24(data.bytes + 7) + 1;
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} else { // Single image case.
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const WebPMuxImage* const wpi = mux->images_;
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WebPMuxError err = ValidateForSingleImage(mux);
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if (err != WEBP_MUX_OK) return err;
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assert(wpi != NULL);
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w = wpi->width_;
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h = wpi->height_;
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if (wpi->has_alpha_) f |= ALPHA_FLAG;
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}
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if (w * (uint64_t)h >= MAX_IMAGE_AREA) return WEBP_MUX_BAD_DATA;
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if (width != NULL) *width = w;
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if (height != NULL) *height = h;
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if (flags != NULL) *flags = f;
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return WEBP_MUX_OK;
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}
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WebPMuxError WebPMuxGetCanvasSize(const WebPMux* mux, int* width, int* height) {
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if (mux == NULL || width == NULL || height == NULL) {
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return WEBP_MUX_INVALID_ARGUMENT;
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}
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return MuxGetCanvasInfo(mux, width, height, NULL);
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}
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WebPMuxError WebPMuxGetFeatures(const WebPMux* mux, uint32_t* flags) {
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if (mux == NULL || flags == NULL) return WEBP_MUX_INVALID_ARGUMENT;
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return MuxGetCanvasInfo(mux, NULL, NULL, flags);
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}
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static uint8_t* EmitVP8XChunk(uint8_t* const dst, int width,
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int height, uint32_t flags) {
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const size_t vp8x_size = CHUNK_HEADER_SIZE + VP8X_CHUNK_SIZE;
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assert(width >= 1 && height >= 1);
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assert(width <= MAX_CANVAS_SIZE && height <= MAX_CANVAS_SIZE);
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assert(width * (uint64_t)height < MAX_IMAGE_AREA);
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PutLE32(dst, MKFOURCC('V', 'P', '8', 'X'));
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PutLE32(dst + TAG_SIZE, VP8X_CHUNK_SIZE);
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PutLE32(dst + CHUNK_HEADER_SIZE, flags);
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PutLE24(dst + CHUNK_HEADER_SIZE + 4, width - 1);
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PutLE24(dst + CHUNK_HEADER_SIZE + 7, height - 1);
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return dst + vp8x_size;
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}
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// Assemble a single image WebP bitstream from 'wpi'.
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static WebPMuxError SynthesizeBitstream(const WebPMuxImage* const wpi,
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WebPData* const bitstream) {
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uint8_t* dst;
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// Allocate data.
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const int need_vp8x = (wpi->alpha_ != NULL);
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const size_t vp8x_size = need_vp8x ? CHUNK_HEADER_SIZE + VP8X_CHUNK_SIZE : 0;
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const size_t alpha_size = need_vp8x ? ChunkDiskSize(wpi->alpha_) : 0;
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// Note: No need to output ANMF/FRGM chunk for a single image.
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const size_t size = RIFF_HEADER_SIZE + vp8x_size + alpha_size +
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ChunkDiskSize(wpi->img_);
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uint8_t* const data = (uint8_t*)malloc(size);
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if (data == NULL) return WEBP_MUX_MEMORY_ERROR;
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// Main RIFF header.
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dst = MuxEmitRiffHeader(data, size);
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if (need_vp8x) {
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dst = EmitVP8XChunk(dst, wpi->width_, wpi->height_, ALPHA_FLAG); // VP8X.
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dst = ChunkListEmit(wpi->alpha_, dst); // ALPH.
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}
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// Bitstream.
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dst = ChunkListEmit(wpi->img_, dst);
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assert(dst == data + size);
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// Output.
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bitstream->bytes = data;
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bitstream->size = size;
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return WEBP_MUX_OK;
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}
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WebPMuxError WebPMuxGetChunk(const WebPMux* mux, const char fourcc[4],
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WebPData* chunk_data) {
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CHUNK_INDEX idx;
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if (mux == NULL || fourcc == NULL || chunk_data == NULL) {
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return WEBP_MUX_INVALID_ARGUMENT;
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}
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idx = ChunkGetIndexFromFourCC(fourcc);
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if (IsWPI(kChunks[idx].id)) { // An image chunk.
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return WEBP_MUX_INVALID_ARGUMENT;
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} else if (idx != IDX_UNKNOWN) { // A known chunk type.
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return MuxGet(mux, idx, 1, chunk_data);
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} else { // An unknown chunk type.
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const WebPChunk* const chunk =
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ChunkSearchList(mux->unknown_, 1, ChunkGetTagFromFourCC(fourcc));
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if (chunk == NULL) return WEBP_MUX_NOT_FOUND;
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*chunk_data = chunk->data_;
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return WEBP_MUX_OK;
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}
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}
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static WebPMuxError MuxGetImageInternal(const WebPMuxImage* const wpi,
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WebPMuxFrameInfo* const info) {
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// Set some defaults for unrelated fields.
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info->x_offset = 0;
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info->y_offset = 0;
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info->duration = 1;
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info->dispose_method = WEBP_MUX_DISPOSE_NONE;
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info->blend_method = WEBP_MUX_BLEND;
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// Extract data for related fields.
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info->id = ChunkGetIdFromTag(wpi->img_->tag_);
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return SynthesizeBitstream(wpi, &info->bitstream);
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}
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static WebPMuxError MuxGetFrameFragmentInternal(const WebPMuxImage* const wpi,
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WebPMuxFrameInfo* const frame) {
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const int is_frame = (wpi->header_->tag_ == kChunks[IDX_ANMF].tag);
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const CHUNK_INDEX idx = is_frame ? IDX_ANMF : IDX_FRGM;
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const WebPData* frame_frgm_data;
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#ifndef WEBP_EXPERIMENTAL_FEATURES
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if (!is_frame) return WEBP_MUX_INVALID_ARGUMENT;
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#endif
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assert(wpi->header_ != NULL); // Already checked by WebPMuxGetFrame().
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// Get frame/fragment chunk.
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frame_frgm_data = &wpi->header_->data_;
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if (frame_frgm_data->size < kChunks[idx].size) return WEBP_MUX_BAD_DATA;
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// Extract info.
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frame->x_offset = 2 * GetLE24(frame_frgm_data->bytes + 0);
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frame->y_offset = 2 * GetLE24(frame_frgm_data->bytes + 3);
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if (is_frame) {
|
|
const uint8_t bits = frame_frgm_data->bytes[15];
|
|
frame->duration = GetLE24(frame_frgm_data->bytes + 12);
|
|
frame->dispose_method =
|
|
(bits & 1) ? WEBP_MUX_DISPOSE_BACKGROUND : WEBP_MUX_DISPOSE_NONE;
|
|
frame->blend_method = (bits & 2) ? WEBP_MUX_NO_BLEND : WEBP_MUX_BLEND;
|
|
} else { // Defaults for unused values.
|
|
frame->duration = 1;
|
|
frame->dispose_method = WEBP_MUX_DISPOSE_NONE;
|
|
frame->blend_method = WEBP_MUX_BLEND;
|
|
}
|
|
frame->id = ChunkGetIdFromTag(wpi->header_->tag_);
|
|
return SynthesizeBitstream(wpi, &frame->bitstream);
|
|
}
|
|
|
|
WebPMuxError WebPMuxGetFrame(
|
|
const WebPMux* mux, uint32_t nth, WebPMuxFrameInfo* frame) {
|
|
WebPMuxError err;
|
|
WebPMuxImage* wpi;
|
|
|
|
// Sanity checks.
|
|
if (mux == NULL || frame == NULL) {
|
|
return WEBP_MUX_INVALID_ARGUMENT;
|
|
}
|
|
|
|
// Get the nth WebPMuxImage.
|
|
err = MuxImageGetNth((const WebPMuxImage**)&mux->images_, nth, &wpi);
|
|
if (err != WEBP_MUX_OK) return err;
|
|
|
|
// Get frame info.
|
|
if (wpi->header_ == NULL) {
|
|
return MuxGetImageInternal(wpi, frame);
|
|
} else {
|
|
return MuxGetFrameFragmentInternal(wpi, frame);
|
|
}
|
|
}
|
|
|
|
WebPMuxError WebPMuxGetAnimationParams(const WebPMux* mux,
|
|
WebPMuxAnimParams* params) {
|
|
WebPData anim;
|
|
WebPMuxError err;
|
|
|
|
if (mux == NULL || params == NULL) return WEBP_MUX_INVALID_ARGUMENT;
|
|
|
|
err = MuxGet(mux, IDX_ANIM, 1, &anim);
|
|
if (err != WEBP_MUX_OK) return err;
|
|
if (anim.size < kChunks[WEBP_CHUNK_ANIM].size) return WEBP_MUX_BAD_DATA;
|
|
params->bgcolor = GetLE32(anim.bytes);
|
|
params->loop_count = GetLE16(anim.bytes + 4);
|
|
|
|
return WEBP_MUX_OK;
|
|
}
|
|
|
|
// Get chunk index from chunk id. Returns IDX_NIL if not found.
|
|
static CHUNK_INDEX ChunkGetIndexFromId(WebPChunkId id) {
|
|
int i;
|
|
for (i = 0; kChunks[i].id != WEBP_CHUNK_NIL; ++i) {
|
|
if (id == kChunks[i].id) return (CHUNK_INDEX)i;
|
|
}
|
|
return IDX_NIL;
|
|
}
|
|
|
|
// Count number of chunks matching 'tag' in the 'chunk_list'.
|
|
// If tag == NIL_TAG, any tag will be matched.
|
|
static int CountChunks(const WebPChunk* const chunk_list, uint32_t tag) {
|
|
int count = 0;
|
|
const WebPChunk* current;
|
|
for (current = chunk_list; current != NULL; current = current->next_) {
|
|
if (tag == NIL_TAG || current->tag_ == tag) {
|
|
count++; // Count chunks whose tags match.
|
|
}
|
|
}
|
|
return count;
|
|
}
|
|
|
|
WebPMuxError WebPMuxNumChunks(const WebPMux* mux,
|
|
WebPChunkId id, int* num_elements) {
|
|
if (mux == NULL || num_elements == NULL) {
|
|
return WEBP_MUX_INVALID_ARGUMENT;
|
|
}
|
|
|
|
if (IsWPI(id)) {
|
|
*num_elements = MuxImageCount(mux->images_, id);
|
|
} else {
|
|
WebPChunk* const* chunk_list = MuxGetChunkListFromId(mux, id);
|
|
const CHUNK_INDEX idx = ChunkGetIndexFromId(id);
|
|
*num_elements = CountChunks(*chunk_list, kChunks[idx].tag);
|
|
}
|
|
|
|
return WEBP_MUX_OK;
|
|
}
|
|
|
|
//------------------------------------------------------------------------------
|
|
|