WebPMuxError WebPMuxAssemble(WebPMux* mux, WebPData* assembled_data) {
size_t size = 0;
uint8_t* data = NULL;
uint8_t* dst = NULL;
WebPMuxError err;
if (assembled_data == NULL) {
return WEBP_MUX_INVALID_ARGUMENT;
}
// Clean up returned data, in case something goes wrong.
memset(assembled_data, 0, sizeof(*assembled_data));
if (mux == NULL) {
return WEBP_MUX_INVALID_ARGUMENT;
}
// Finalize mux.
err = MuxCleanup(mux);
if (err != WEBP_MUX_OK) return err;
err = CreateVP8XChunk(mux);
if (err != WEBP_MUX_OK) return err;
// Allocate data.
size = ChunkListDiskSize(mux->vp8x_) + ChunkListDiskSize(mux->iccp_)
+ ChunkListDiskSize(mux->anim_) + ImageListDiskSize(mux->images_)
+ ChunkListDiskSize(mux->exif_) + ChunkListDiskSize(mux->xmp_)
+ ChunkListDiskSize(mux->unknown_) + RIFF_HEADER_SIZE;
data = (uint8_t*)WebPSafeMalloc(1ULL, size);
if (data == NULL) return WEBP_MUX_MEMORY_ERROR;
// Emit header & chunks.
dst = MuxEmitRiffHeader(data, size);
dst = ChunkListEmit(mux->vp8x_, dst);
dst = ChunkListEmit(mux->iccp_, dst);
dst = ChunkListEmit(mux->anim_, dst);
dst = ImageListEmit(mux->images_, dst);
dst = ChunkListEmit(mux->exif_, dst);
dst = ChunkListEmit(mux->xmp_, dst);
dst = ChunkListEmit(mux->unknown_, dst);
assert(dst == data + size);
// Validate mux.
err = MuxValidate(mux);
if (err != WEBP_MUX_OK) {
WebPSafeFree(data);
data = NULL;
size = 0;
}
// Finalize data.
assembled_data->bytes = data;
assembled_data->size = size;
return err;
}
WebPMux* WebPMuxCreateInternal(const WebPData* bitstream, int copy_data,
int version) {
size_t riff_size;
uint32_t tag;
const uint8_t* end;
WebPMux* mux = NULL;
WebPMuxImage* wpi = NULL;
const uint8_t* data;
size_t size;
WebPChunk chunk;
ChunkInit(&chunk);
// Sanity checks.
if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_MUX_ABI_VERSION)) {
return NULL; // version mismatch
}
if (bitstream == NULL) return NULL;
data = bitstream->bytes;
size = bitstream->size;
if (data == NULL) return NULL;
if (size < RIFF_HEADER_SIZE) return NULL;
if (GetLE32(data + 0) != MKFOURCC('R', 'I', 'F', 'F') ||
GetLE32(data + CHUNK_HEADER_SIZE) != MKFOURCC('W', 'E', 'B', 'P')) {
return NULL;
}
mux = WebPMuxNew();
if (mux == NULL) return NULL;
if (size < RIFF_HEADER_SIZE + TAG_SIZE) goto Err;
tag = GetLE32(data + RIFF_HEADER_SIZE);
if (tag != kChunks[IDX_VP8].tag &&
tag != kChunks[IDX_VP8L].tag &&
tag != kChunks[IDX_VP8X].tag) {
goto Err; // First chunk should be VP8, VP8L or VP8X.
}
riff_size = SizeWithPadding(GetLE32(data + TAG_SIZE));
if (riff_size > MAX_CHUNK_PAYLOAD || riff_size > size) {
goto Err;
} else {
if (riff_size < size) { // Redundant data after last chunk.
size = riff_size; // To make sure we don't read any data beyond mux_size.
}
}
end = data + size;
data += RIFF_HEADER_SIZE;
size -= RIFF_HEADER_SIZE;
wpi = (WebPMuxImage*)WebPSafeMalloc(1ULL, sizeof(*wpi));
if (wpi == NULL) goto Err;
MuxImageInit(wpi);
// Loop over chunks.
while (data != end) {
size_t data_size;
WebPChunkId id;
WebPChunk** chunk_list;
if (ChunkVerifyAndAssign(&chunk, data, size, riff_size,
copy_data) != WEBP_MUX_OK) {
goto Err;
}
data_size = ChunkDiskSize(&chunk);
id = ChunkGetIdFromTag(chunk.tag_);
switch (id) {
case WEBP_CHUNK_ALPHA:
if (wpi->alpha_ != NULL) goto Err; // Consecutive ALPH chunks.
if (ChunkSetNth(&chunk, &wpi->alpha_, 1) != WEBP_MUX_OK) goto Err;
wpi->is_partial_ = 1; // Waiting for a VP8 chunk.
break;
case WEBP_CHUNK_IMAGE:
if (ChunkSetNth(&chunk, &wpi->img_, 1) != WEBP_MUX_OK) goto Err;
if (!MuxImageFinalize(wpi)) goto Err;
wpi->is_partial_ = 0; // wpi is completely filled.
PushImage:
// Add this to mux->images_ list.
if (MuxImagePush(wpi, &mux->images_) != WEBP_MUX_OK) goto Err;
MuxImageInit(wpi); // Reset for reading next image.
break;
case WEBP_CHUNK_ANMF:
if (wpi->is_partial_) goto Err; // Previous wpi is still incomplete.
if (!MuxImageParse(&chunk, copy_data, wpi)) goto Err;
ChunkRelease(&chunk);
goto PushImage;
break;
default: // A non-image chunk.
if (wpi->is_partial_) goto Err; // Encountered a non-image chunk before
// getting all chunks of an image.
chunk_list = MuxGetChunkListFromId(mux, id); // List to add this chunk.
if (ChunkSetNth(&chunk, chunk_list, 0) != WEBP_MUX_OK) goto Err;
if (id == WEBP_CHUNK_VP8X) { // grab global specs
mux->canvas_width_ = GetLE24(data + 12) + 1;
mux->canvas_height_ = GetLE24(data + 15) + 1;
}
break;
}
data += data_size;
size -= data_size;
ChunkInit(&chunk);
}
// Validate mux if complete.
if (MuxValidate(mux) != WEBP_MUX_OK) goto Err;
MuxImageDelete(wpi);
return mux; // All OK;
Err: // Something bad happened.
ChunkRelease(&chunk);
MuxImageDelete(wpi);
WebPMuxDelete(mux);
return NULL;
}
WebPMuxError WebPMuxAssemble(WebPMux* mux, WebPData* assembled_data) {
size_t size = 0;
uint8_t* data = NULL;
uint8_t* dst = NULL;
int num_frames;
int num_loop_chunks;
WebPMuxError err;
if (mux == NULL || assembled_data == NULL) {
return WEBP_MUX_INVALID_ARGUMENT;
}
// Remove LOOP chunk if unnecessary.
err = WebPMuxNumChunks(mux, kChunks[IDX_LOOP].id, &num_loop_chunks);
if (err != WEBP_MUX_OK) return err;
if (num_loop_chunks >= 1) {
err = WebPMuxNumChunks(mux, kChunks[IDX_FRAME].id, &num_frames);
if (err != WEBP_MUX_OK) return err;
if (num_frames == 0) {
err = DeleteLoopCount(mux);
if (err != WEBP_MUX_OK) return err;
}
}
// Create VP8X chunk.
err = CreateVP8XChunk(mux);
if (err != WEBP_MUX_OK) return err;
// Allocate data.
size = ChunksListDiskSize(mux->vp8x_) + ChunksListDiskSize(mux->iccp_)
+ ChunksListDiskSize(mux->loop_) + MuxImageListDiskSize(mux->images_)
+ ChunksListDiskSize(mux->meta_) + ChunksListDiskSize(mux->unknown_)
+ RIFF_HEADER_SIZE;
data = (uint8_t*)malloc(size);
if (data == NULL) return WEBP_MUX_MEMORY_ERROR;
// Emit header & chunks.
dst = MuxEmitRiffHeader(data, size);
dst = ChunkListEmit(mux->vp8x_, dst);
dst = ChunkListEmit(mux->iccp_, dst);
dst = ChunkListEmit(mux->loop_, dst);
dst = MuxImageListEmit(mux->images_, dst);
dst = ChunkListEmit(mux->meta_, dst);
dst = ChunkListEmit(mux->unknown_, dst);
assert(dst == data + size);
// Validate mux.
err = MuxValidate(mux);
if (err != WEBP_MUX_OK) {
free(data);
data = NULL;
size = 0;
}
// Finalize.
assembled_data->bytes_ = data;
assembled_data->size_ = size;
return err;
}
