// Extracts image & alpha data from the given bitstream and then sets wpi.alpha_
// and wpi.img_ appropriately.
static WebPMuxError SetAlphaAndImageChunks(
const WebPData* const bitstream, int copy_data, WebPMuxImage* const wpi) {
int is_lossless = 0;
WebPData image, alpha;
WebPMuxError err = GetImageData(bitstream, &image, &alpha, &is_lossless);
const int image_tag =
is_lossless ? kChunks[IDX_VP8L].tag : kChunks[IDX_VP8].tag;
if (err != WEBP_MUX_OK) return err;
if (alpha.bytes != NULL) {
err = AddDataToChunkList(&alpha, copy_data, kChunks[IDX_ALPHA].tag,
&wpi->alpha_);
if (err != WEBP_MUX_OK) return err;
}
return AddDataToChunkList(&image, copy_data, image_tag, &wpi->img_);
}
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;
}
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;
}