static WebPMuxError MuxGetFrameFragmentInternal(const WebPMuxImage* const wpi,
WebPMuxFrameInfo* const frame) {
const int is_frame = (wpi->header_->tag_ == kChunks[IDX_ANMF].tag);
const CHUNK_INDEX idx = is_frame ? IDX_ANMF : IDX_FRGM;
const WebPData* frame_frgm_data;
if (!is_frame) return WEBP_MUX_INVALID_ARGUMENT;
assert(wpi->header_ != NULL); // Already checked by WebPMuxGetFrame().
// Get frame/fragment chunk.
frame_frgm_data = &wpi->header_->data_;
if (frame_frgm_data->size < kChunks[idx].size) return WEBP_MUX_BAD_DATA;
// Extract info.
frame->x_offset = 2 * GetLE24(frame_frgm_data->bytes + 0);
frame->y_offset = 2 * GetLE24(frame_frgm_data->bytes + 3);
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);
}
static WebPMuxError MuxGetImageInternal(const WebPMuxImage* const wpi,
WebPMuxFrameInfo* const info) {
// Set some defaults for unrelated fields.
info->x_offset = 0;
info->y_offset = 0;
info->duration = 1;
info->dispose_method = WEBP_MUX_DISPOSE_NONE;
info->blend_method = WEBP_MUX_BLEND;
// Extract data for related fields.
info->id = ChunkGetIdFromTag(wpi->img_->tag_);
return SynthesizeBitstream(wpi, &info->bitstream);
}
static WebPMuxError MuxDeleteAllNamedData(WebPMux* const mux, uint32_t tag) {
const WebPChunkId id = ChunkGetIdFromTag(tag);
WebPChunk** chunk_list;
assert(mux != NULL);
if (IsWPI(id)) return WEBP_MUX_INVALID_ARGUMENT;
chunk_list = MuxGetChunkListFromId(mux, id);
if (chunk_list == NULL) return WEBP_MUX_INVALID_ARGUMENT;
return DeleteChunks(chunk_list, tag);
}
int MuxImageCount(const WebPMuxImage* wpi_list, WebPChunkId id) {
int count = 0;
const WebPMuxImage* current;
for (current = wpi_list; current != NULL; current = current->next_) {
if (id == WEBP_CHUNK_NIL) {
++count; // Special case: count all images.
} else {
const WebPChunk* const wpi_chunk = *GetChunkListFromId(current, id);
if (wpi_chunk != NULL) {
const WebPChunkId wpi_chunk_id = ChunkGetIdFromTag(wpi_chunk->tag_);
if (wpi_chunk_id == id) ++count; // Count images with a matching 'id'.
}
}
}
return count;
}
WebPMuxError WebPMuxPushFrame(WebPMux* mux, const WebPMuxFrameInfo* frame,
int copy_data) {
WebPMuxImage wpi;
WebPMuxError err;
int is_frame;
const WebPData* const bitstream = &frame->bitstream;
// Sanity checks.
if (mux == NULL || frame == NULL) return WEBP_MUX_INVALID_ARGUMENT;
is_frame = (frame->id == WEBP_CHUNK_ANMF);
if (!(is_frame || (frame->id == WEBP_CHUNK_FRGM))) {
return WEBP_MUX_INVALID_ARGUMENT;
}
#ifndef WEBP_EXPERIMENTAL_FEATURES
if (frame->id == WEBP_CHUNK_FRGM) { // disabled for now.
return WEBP_MUX_INVALID_ARGUMENT;
}
#endif
if (bitstream->bytes == NULL || bitstream->size > MAX_CHUNK_PAYLOAD) {
return WEBP_MUX_INVALID_ARGUMENT;
}
if (mux->images_ != NULL) {
const WebPMuxImage* const image = mux->images_;
const uint32_t image_id = (image->header_ != NULL) ?
ChunkGetIdFromTag(image->header_->tag_) : WEBP_CHUNK_IMAGE;
if (image_id != frame->id) {
return WEBP_MUX_INVALID_ARGUMENT; // Conflicting frame types.
}
}
MuxImageInit(&wpi);
err = SetAlphaAndImageChunks(bitstream, copy_data, &wpi);
if (err != WEBP_MUX_OK) goto Err;
assert(wpi.img_ != NULL); // As SetAlphaAndImageChunks() was successful.
{
WebPData frame_frgm;
const uint32_t tag = kChunks[is_frame ? IDX_ANMF : IDX_FRGM].tag;
WebPMuxFrameInfo tmp = *frame;
tmp.x_offset &= ~1; // Snap offsets to even.
tmp.y_offset &= ~1;
if (!is_frame) { // Reset unused values.
tmp.duration = 1;
tmp.dispose_method = WEBP_MUX_DISPOSE_NONE;
tmp.blend_method = WEBP_MUX_BLEND;
}
if (tmp.x_offset < 0 || tmp.x_offset >= MAX_POSITION_OFFSET ||
tmp.y_offset < 0 || tmp.y_offset >= MAX_POSITION_OFFSET ||
(tmp.duration < 0 || tmp.duration >= MAX_DURATION) ||
tmp.dispose_method != (tmp.dispose_method & 1)) {
err = WEBP_MUX_INVALID_ARGUMENT;
goto Err;
}
err = CreateFrameFragmentData(wpi.width_, wpi.height_, &tmp, is_frame,
&frame_frgm);
if (err != WEBP_MUX_OK) goto Err;
// Add frame/fragment chunk (with copy_data = 1).
err = AddDataToChunkList(&frame_frgm, 1, tag, &wpi.header_);
WebPDataClear(&frame_frgm); // frame_frgm owned by wpi.header_ now.
if (err != WEBP_MUX_OK) goto Err;
}
// Add this WebPMuxImage to mux.
err = MuxImagePush(&wpi, &mux->images_);
if (err != WEBP_MUX_OK) goto Err;
// All is well.
return WEBP_MUX_OK;
Err: // Something bad happened.
MuxImageRelease(&wpi);
return err;
}
static int MuxImageParse(const WebPChunk* const chunk, int copy_data,
WebPMuxImage* const wpi) {
const uint8_t* bytes = chunk->data_.bytes;
size_t size = chunk->data_.size;
const uint8_t* const last = bytes + size;
WebPChunk subchunk;
size_t subchunk_size;
ChunkInit(&subchunk);
assert(chunk->tag_ == kChunks[IDX_ANMF].tag ||
chunk->tag_ == kChunks[IDX_FRGM].tag);
assert(!wpi->is_partial_);
// ANMF/FRGM.
{
const size_t hdr_size = (chunk->tag_ == kChunks[IDX_ANMF].tag) ?
ANMF_CHUNK_SIZE : FRGM_CHUNK_SIZE;
const WebPData temp = { bytes, hdr_size };
// Each of ANMF and FRGM chunk contain a header at the beginning. So, its
// size should at least be 'hdr_size'.
if (size < hdr_size) goto Fail;
ChunkAssignData(&subchunk, &temp, copy_data, chunk->tag_);
}
ChunkSetNth(&subchunk, &wpi->header_, 1);
wpi->is_partial_ = 1; // Waiting for ALPH and/or VP8/VP8L chunks.
// Rest of the chunks.
subchunk_size = ChunkDiskSize(&subchunk) - CHUNK_HEADER_SIZE;
bytes += subchunk_size;
size -= subchunk_size;
while (bytes != last) {
ChunkInit(&subchunk);
if (ChunkVerifyAndAssign(&subchunk, bytes, size, size,
copy_data) != WEBP_MUX_OK) {
goto Fail;
}
switch (ChunkGetIdFromTag(subchunk.tag_)) {
case WEBP_CHUNK_ALPHA:
if (wpi->alpha_ != NULL) goto Fail; // Consecutive ALPH chunks.
if (ChunkSetNth(&subchunk, &wpi->alpha_, 1) != WEBP_MUX_OK) goto Fail;
wpi->is_partial_ = 1; // Waiting for a VP8 chunk.
break;
case WEBP_CHUNK_IMAGE:
if (ChunkSetNth(&subchunk, &wpi->img_, 1) != WEBP_MUX_OK) goto Fail;
if (!MuxImageFinalize(wpi)) goto Fail;
wpi->is_partial_ = 0; // wpi is completely filled.
break;
case WEBP_CHUNK_UNKNOWN:
if (wpi->is_partial_) goto Fail; // Encountered an unknown chunk
// before some image chunks.
if (ChunkSetNth(&subchunk, &wpi->unknown_, 0) != WEBP_MUX_OK) goto Fail;
break;
default:
goto Fail;
break;
}
subchunk_size = ChunkDiskSize(&subchunk);
bytes += subchunk_size;
size -= subchunk_size;
}
if (wpi->is_partial_) goto Fail;
return 1;
Fail:
ChunkRelease(&subchunk);
return 0;
}
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 WebPMuxPushFrame(WebPMux* mux, const WebPMuxFrameInfo* info,
int copy_data) {
WebPMuxImage wpi;
WebPMuxError err;
// Sanity checks.
if (mux == NULL || info == NULL) return WEBP_MUX_INVALID_ARGUMENT;
if (info->id != WEBP_CHUNK_ANMF) return WEBP_MUX_INVALID_ARGUMENT;
if (info->bitstream.bytes == NULL ||
info->bitstream.size > MAX_CHUNK_PAYLOAD) {
return WEBP_MUX_INVALID_ARGUMENT;
}
if (mux->images_ != NULL) {
const WebPMuxImage* const image = mux->images_;
const uint32_t image_id = (image->header_ != NULL) ?
ChunkGetIdFromTag(image->header_->tag_) : WEBP_CHUNK_IMAGE;
if (image_id != info->id) {
return WEBP_MUX_INVALID_ARGUMENT; // Conflicting frame types.
}
}
MuxImageInit(&wpi);
err = SetAlphaAndImageChunks(&info->bitstream, copy_data, &wpi);
if (err != WEBP_MUX_OK) goto Err;
assert(wpi.img_ != NULL); // As SetAlphaAndImageChunks() was successful.
{
WebPData frame;
const uint32_t tag = kChunks[IDX_ANMF].tag;
WebPMuxFrameInfo tmp = *info;
tmp.x_offset &= ~1; // Snap offsets to even.
tmp.y_offset &= ~1;
if (tmp.x_offset < 0 || tmp.x_offset >= MAX_POSITION_OFFSET ||
tmp.y_offset < 0 || tmp.y_offset >= MAX_POSITION_OFFSET ||
(tmp.duration < 0 || tmp.duration >= MAX_DURATION) ||
tmp.dispose_method != (tmp.dispose_method & 1)) {
err = WEBP_MUX_INVALID_ARGUMENT;
goto Err;
}
err = CreateFrameData(wpi.width_, wpi.height_, &tmp, &frame);
if (err != WEBP_MUX_OK) goto Err;
// Add frame chunk (with copy_data = 1).
err = AddDataToChunkList(&frame, 1, tag, &wpi.header_);
WebPDataClear(&frame); // frame owned by wpi.header_ now.
if (err != WEBP_MUX_OK) goto Err;
}
// Add this WebPMuxImage to mux.
err = MuxImagePush(&wpi, &mux->images_);
if (err != WEBP_MUX_OK) goto Err;
// All is well.
return WEBP_MUX_OK;
Err: // Something bad happened.
MuxImageRelease(&wpi);
return err;
}
