WebPMuxError WebPMuxSetAnimationParams(WebPMux* mux,
const WebPMuxAnimParams* params) {
WebPMuxError err;
uint8_t data[ANIM_CHUNK_SIZE];
if (mux == NULL || params == NULL) return WEBP_MUX_INVALID_ARGUMENT;
if (params->loop_count < 0 || params->loop_count >= MAX_LOOP_COUNT) {
return WEBP_MUX_INVALID_ARGUMENT;
}
// Delete any existing ANIM chunk(s).
err = MuxDeleteAllNamedData(mux, kChunks[IDX_ANIM].tag);
if (err != WEBP_MUX_OK && err != WEBP_MUX_NOT_FOUND) return err;
// Set the animation parameters.
PutLE32(data, params->bgcolor);
PutLE16(data + 4, params->loop_count);
return MuxAddChunk(mux, 1, kChunks[IDX_ANIM].tag, data, sizeof(data), 1);
}
WebPMuxError WebPMuxSetLoopCount(WebPMux* mux, int loop_count) {
WebPMuxError err;
uint8_t* data = NULL;
if (mux == NULL) return WEBP_MUX_INVALID_ARGUMENT;
if (loop_count >= MAX_LOOP_COUNT) return WEBP_MUX_INVALID_ARGUMENT;
// Delete the existing LOOP chunk(s).
err = DeleteLoopCount(mux);
if (err != WEBP_MUX_OK && err != WEBP_MUX_NOT_FOUND) return err;
// Add the given loop count.
data = (uint8_t*)malloc(kChunks[IDX_LOOP].size);
if (data == NULL) return WEBP_MUX_MEMORY_ERROR;
PutLE16(data, loop_count);
err = MuxAddChunk(mux, 1, kChunks[IDX_LOOP].tag, data,
kChunks[IDX_LOOP].size, 1);
free(data);
return err;
}
// VP8X format:
// Total Size : 10,
// Flags : 4 bytes,
// Width : 3 bytes,
// Height : 3 bytes.
static WebPMuxError CreateVP8XChunk(WebPMux* const mux) {
WebPMuxError err = WEBP_MUX_OK;
uint32_t flags = 0;
int width = 0;
int height = 0;
uint8_t data[VP8X_CHUNK_SIZE];
const size_t data_size = VP8X_CHUNK_SIZE;
const WebPMuxImage* images = NULL;
assert(mux != NULL);
images = mux->images_; // First image.
if (images == NULL || images->img_ == NULL ||
images->img_->data_.bytes_ == NULL) {
return WEBP_MUX_INVALID_ARGUMENT;
}
// If VP8X chunk(s) is(are) already present, remove them (and later add new
// VP8X chunk with updated flags).
err = MuxDeleteAllNamedData(mux, IDX_VP8X);
if (err != WEBP_MUX_OK && err != WEBP_MUX_NOT_FOUND) return err;
// Set flags.
if (mux->iccp_ != NULL && mux->iccp_->data_.bytes_ != NULL) {
flags |= ICCP_FLAG;
}
if (mux->meta_ != NULL && mux->meta_->data_.bytes_ != NULL) {
flags |= META_FLAG;
}
if (images->header_ != NULL) {
if (images->header_->tag_ == kChunks[IDX_TILE].tag) {
// This is a tiled image.
flags |= TILE_FLAG;
} else if (images->header_->tag_ == kChunks[IDX_FRAME].tag) {
// This is an image with animation.
flags |= ANIMATION_FLAG;
}
}
if (MuxImageCount(images, WEBP_CHUNK_ALPHA) > 0) {
flags |= ALPHA_FLAG; // Some images have an alpha channel.
}
if (flags == 0) {
// For Simple Image, VP8X chunk should not be added.
return WEBP_MUX_OK;
}
err = GetImageCanvasWidthHeight(mux, flags, &width, &height);
if (err != WEBP_MUX_OK) return err;
if (width <= 0 || height <= 0) {
return WEBP_MUX_INVALID_ARGUMENT;
}
if (width > MAX_CANVAS_SIZE || height > MAX_CANVAS_SIZE) {
return WEBP_MUX_INVALID_ARGUMENT;
}
if (MuxHasLosslessImages(images)) {
// We have a file with a VP8X chunk having some lossless images.
// As lossless images implicitly contain alpha, force ALPHA_FLAG to be true.
// Note: This 'flags' update must NOT be done for a lossless image
// without a VP8X chunk!
flags |= ALPHA_FLAG;
}
PutLE32(data + 0, flags); // VP8X chunk flags.
PutLE24(data + 4, width - 1); // canvas width.
PutLE24(data + 7, height - 1); // canvas height.
err = MuxAddChunk(mux, 1, kChunks[IDX_VP8X].tag, data, data_size, 1);
return err;
}
