int WebPInitDecoderConfigInternal(WebPDecoderConfig* config,
int version) {
if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_DECODER_ABI_VERSION)) {
return 0; // version mismatch
}
if (config == NULL) {
return 0;
}
memset(config, 0, sizeof(*config));
DefaultFeatures(&config->input);
WebPInitDecBuffer(&config->output);
return 1;
}
WebPDemuxer* WebPDemuxInternal(const WebPData* data, int allow_partial,
WebPDemuxState* state, int version) {
const ChunkParser* parser;
int partial;
ParseStatus status = PARSE_ERROR;
MemBuffer mem;
WebPDemuxer* dmux;
if (state != NULL) *state = WEBP_DEMUX_PARSE_ERROR;
if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_DEMUX_ABI_VERSION)) return NULL;
if (data == NULL || data->bytes == NULL || data->size == 0) return NULL;
if (!InitMemBuffer(&mem, data->bytes, data->size)) return NULL;
status = ReadHeader(&mem);
if (status != PARSE_OK) {
if (state != NULL) {
*state = (status == PARSE_NEED_MORE_DATA) ? WEBP_DEMUX_PARSING_HEADER
: WEBP_DEMUX_PARSE_ERROR;
}
return NULL;
}
partial = (mem.buf_size_ < mem.riff_end_);
if (!allow_partial && partial) return NULL;
dmux = (WebPDemuxer*)calloc(1, sizeof(*dmux));
if (dmux == NULL) return NULL;
InitDemux(dmux, &mem);
status = PARSE_ERROR;
for (parser = kMasterChunks; parser->parse != NULL; ++parser) {
if (!memcmp(parser->id, GetBuffer(&dmux->mem_), TAG_SIZE)) {
status = parser->parse(dmux);
if (status == PARSE_OK) dmux->state_ = WEBP_DEMUX_DONE;
if (status == PARSE_NEED_MORE_DATA && !partial) status = PARSE_ERROR;
if (status != PARSE_ERROR && !parser->valid(dmux)) status = PARSE_ERROR;
if (status == PARSE_ERROR) dmux->state_ = WEBP_DEMUX_PARSE_ERROR;
break;
}
}
if (state != NULL) *state = dmux->state_;
if (status == PARSE_ERROR) {
WebPDemuxDelete(dmux);
return NULL;
}
return dmux;
}
VP8StatusCode WebPGetFeaturesInternal(const uint8_t* data, size_t data_size,
WebPBitstreamFeatures* features,
int version) {
VP8StatusCode status;
if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_DECODER_ABI_VERSION)) {
return VP8_STATUS_INVALID_PARAM; // version mismatch
}
if (features == NULL) {
return VP8_STATUS_INVALID_PARAM;
}
status = GetFeatures(data, data_size, features);
if (status == VP8_STATUS_NOT_ENOUGH_DATA) {
return VP8_STATUS_BITSTREAM_ERROR; // Not-enough-data treated as error.
}
return status;
}
int WebPConfigInitInternal(WebPConfig* config,
WebPPreset preset, float quality, int version) {
if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_ENCODER_ABI_VERSION)) {
return 0; // caller/system version mismatch!
}
if (config == NULL) return 0;
config->quality = quality;
config->target_size = 0;
config->target_PSNR = 0.;
config->method = 0; // 4;
config->sns_strength = 50;
config->filter_strength = 60; // mid-filtering
config->filter_sharpness = 0;
config->filter_type = 1; // default: strong (so U/V is filtered too)
config->partitions = 0;
config->segments = 4;
config->pass = 1;
config->show_compressed = 0;
config->preprocessing = 0;
config->autofilter = 0;
config->partition_limit = 0;
config->alpha_compression = 1;
config->alpha_filtering = 1;
config->alpha_quality = 100;
config->lossless = 0;
config->image_hint = WEBP_HINT_DEFAULT;
config->emulate_jpeg_size = 0;
config->thread_level = 0;
config->low_memory = 0;
// TODO(skal): tune.
switch (preset) {
case WEBP_PRESET_PICTURE:
config->sns_strength = 80;
config->filter_sharpness = 4;
config->filter_strength = 35;
config->preprocessing &= ~2; // no dithering
break;
case WEBP_PRESET_PHOTO:
config->sns_strength = 80;
config->filter_sharpness = 3;
config->filter_strength = 30;
config->preprocessing |= 2;
break;
case WEBP_PRESET_DRAWING:
config->sns_strength = 25;
config->filter_sharpness = 6;
config->filter_strength = 10;
break;
case WEBP_PRESET_ICON:
config->sns_strength = 0;
config->filter_strength = 0; // disable filtering to retain sharpness
config->preprocessing &= ~2; // no dithering
break;
case WEBP_PRESET_TEXT:
config->sns_strength = 0;
config->filter_strength = 0; // disable filtering to retain sharpness
config->preprocessing &= ~2; // no dithering
config->segments = 2;
break;
case WEBP_PRESET_DEFAULT:
default:
break;
}
return WebPValidateConfig(config);
}
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;
}
WebPAnimEncoder* WebPAnimEncoderNewInternal(
int width, int height, const WebPAnimEncoderOptions* enc_options,
int abi_version) {
WebPAnimEncoder* enc;
if (WEBP_ABI_IS_INCOMPATIBLE(abi_version, WEBP_MUX_ABI_VERSION)) {
return NULL;
}
if (width <= 0 || height <= 0 ||
(width * (uint64_t)height) >= MAX_IMAGE_AREA) {
return NULL;
}
enc = (WebPAnimEncoder*)WebPSafeCalloc(1, sizeof(*enc));
if (enc == NULL) return NULL;
// sanity inits, so we can call WebPAnimEncoderDelete():
enc->encoded_frames_ = NULL;
enc->mux_ = NULL;
// Dimensions and options.
*(int*)&enc->canvas_width_ = width;
*(int*)&enc->canvas_height_ = height;
if (enc_options != NULL) {
*(WebPAnimEncoderOptions*)&enc->options_ = *enc_options;
SanitizeEncoderOptions((WebPAnimEncoderOptions*)&enc->options_);
} else {
DefaultEncoderOptions((WebPAnimEncoderOptions*)&enc->options_);
}
// Canvas buffers.
if (!WebPPictureInit(&enc->curr_canvas_copy_) ||
!WebPPictureInit(&enc->prev_canvas_) ||
!WebPPictureInit(&enc->prev_canvas_disposed_)) {
return NULL;
}
enc->curr_canvas_copy_.width = width;
enc->curr_canvas_copy_.height = height;
enc->curr_canvas_copy_.use_argb = 1;
if (!WebPPictureAlloc(&enc->curr_canvas_copy_) ||
!WebPPictureCopy(&enc->curr_canvas_copy_, &enc->prev_canvas_) ||
!WebPPictureCopy(&enc->curr_canvas_copy_, &enc->prev_canvas_disposed_)) {
goto Err;
}
WebPUtilClearPic(&enc->prev_canvas_, NULL);
enc->curr_canvas_copy_modified_ = 1;
// Encoded frames.
ResetCounters(enc);
// Note: one extra storage is for the previous frame.
enc->size_ = enc->options_.kmax - enc->options_.kmin + 1;
// We need space for at least 2 frames. But when kmin, kmax are both zero,
// enc->size_ will be 1. So we handle that special case below.
if (enc->size_ < 2) enc->size_ = 2;
enc->encoded_frames_ =
(EncodedFrame*)WebPSafeCalloc(enc->size_, sizeof(*enc->encoded_frames_));
if (enc->encoded_frames_ == NULL) goto Err;
enc->mux_ = WebPMuxNew();
if (enc->mux_ == NULL) goto Err;
enc->count_since_key_frame_ = 0;
enc->first_timestamp_ = 0;
enc->prev_timestamp_ = 0;
enc->prev_candidate_undecided_ = 0;
enc->is_first_frame_ = 1;
enc->got_null_frame_ = 0;
return enc; // All OK.
Err:
WebPAnimEncoderDelete(enc);
return NULL;
}