WebPMuxImage* MuxImageRelease(WebPMuxImage* const wpi) {
WebPMuxImage* next;
if (wpi == NULL) return NULL;
ChunkDelete(wpi->header_);
ChunkDelete(wpi->alpha_);
ChunkDelete(wpi->img_);
next = wpi->next_;
MuxImageInit(wpi);
return next;
}
// Cleans up 'mux' by removing any unnecessary chunks.
static WebPMuxError MuxCleanup(WebPMux* const mux) {
int num_frames;
int num_fragments;
int num_anim_chunks;
// If we have an image with single fragment or frame, convert it to a
// non-animated non-fragmented image (to avoid writing FRGM/ANMF chunk
// unnecessarily).
WebPMuxError err = WebPMuxNumChunks(mux, kChunks[IDX_ANMF].id, &num_frames);
if (err != WEBP_MUX_OK) return err;
err = WebPMuxNumChunks(mux, kChunks[IDX_FRGM].id, &num_fragments);
if (err != WEBP_MUX_OK) return err;
if (num_frames == 1 || num_fragments == 1) {
WebPMuxImage* frame_frag;
err = MuxImageGetNth((const WebPMuxImage**)&mux->images_, 1, &frame_frag);
assert(err == WEBP_MUX_OK); // We know that one frame/fragment does exist.
if (frame_frag->header_ != NULL) {
assert(frame_frag->header_->tag_ == kChunks[IDX_ANMF].tag ||
frame_frag->header_->tag_ == kChunks[IDX_FRGM].tag);
ChunkDelete(frame_frag->header_); // Removes ANMF/FRGM chunk.
frame_frag->header_ = NULL;
}
num_frames = 0;
num_fragments = 0;
}
// Remove ANIM chunk if this is a non-animated image.
err = WebPMuxNumChunks(mux, kChunks[IDX_ANIM].id, &num_anim_chunks);
if (err != WEBP_MUX_OK) return err;
if (num_anim_chunks >= 1 && num_frames == 0) {
err = MuxDeleteAllNamedData(mux, kChunks[IDX_ANIM].tag);
if (err != WEBP_MUX_OK) return err;
}
return WEBP_MUX_OK;
}
// Cleans up 'mux' by removing any unnecessary chunks.
static WebPMuxError MuxCleanup(WebPMux* const mux) {
int num_frames;
int num_anim_chunks;
// If we have an image with a single frame, and its rectangle
// covers the whole canvas, convert it to a non-animated image
// (to avoid writing ANMF chunk unnecessarily).
WebPMuxError err = WebPMuxNumChunks(mux, kChunks[IDX_ANMF].id, &num_frames);
if (err != WEBP_MUX_OK) return err;
if (num_frames == 1) {
WebPMuxImage* frame = NULL;
err = MuxImageGetNth((const WebPMuxImage**)&mux->images_, 1, &frame);
assert(err == WEBP_MUX_OK); // We know that one frame does exist.
assert(frame != NULL);
if (frame->header_ != NULL &&
((mux->canvas_width_ == 0 && mux->canvas_height_ == 0) ||
(frame->width_ == mux->canvas_width_ &&
frame->height_ == mux->canvas_height_))) {
assert(frame->header_->tag_ == kChunks[IDX_ANMF].tag);
ChunkDelete(frame->header_); // Removes ANMF chunk.
frame->header_ = NULL;
num_frames = 0;
}
}
// Remove ANIM chunk if this is a non-animated image.
err = WebPMuxNumChunks(mux, kChunks[IDX_ANIM].id, &num_anim_chunks);
if (err != WEBP_MUX_OK) return err;
if (num_anim_chunks >= 1 && num_frames == 0) {
err = MuxDeleteAllNamedData(mux, kChunks[IDX_ANIM].tag);
if (err != WEBP_MUX_OK) return err;
}
return WEBP_MUX_OK;
}
static WebPMuxError DeleteChunks(WebPChunk** chunk_list, uint32_t tag) {
WebPMuxError err = WEBP_MUX_NOT_FOUND;
assert(chunk_list);
while (*chunk_list) {
WebPChunk* const chunk = *chunk_list;
if (chunk->tag_ == tag) {
*chunk_list = ChunkDelete(chunk);
err = WEBP_MUX_OK;
} else {
chunk_list = &chunk->next_;
}
}
return err;
}
int MuxImageFinalize(WebPMuxImage* const wpi) {
const WebPChunk* const img = wpi->img_;
const WebPData* const image = &img->data_;
const int is_lossless = (img->tag_ == kChunks[IDX_VP8L].tag);
int w, h;
int vp8l_has_alpha = 0;
const int ok = is_lossless ?
VP8LGetInfo(image->bytes, image->size, &w, &h, &vp8l_has_alpha) :
VP8GetInfo(image->bytes, image->size, image->size, &w, &h);
assert(img != NULL);
if (ok) {
// Ignore ALPH chunk accompanying VP8L.
if (is_lossless && (wpi->alpha_ != NULL)) {
ChunkDelete(wpi->alpha_);
wpi->alpha_ = NULL;
}
wpi->width_ = w;
wpi->height_ = h;
wpi->has_alpha_ = vp8l_has_alpha || (wpi->alpha_ != NULL);
}
return ok;
}
void ChunkListDelete(WebPChunk** const chunk_list) {
while (*chunk_list != NULL) {
*chunk_list = ChunkDelete(*chunk_list);
}
}
static void DeleteAllChunks(WebPChunk** const chunk_list) {
while (*chunk_list) {
*chunk_list = ChunkDelete(*chunk_list);
}
}
