static WebPMuxError MuxGet(WebPMux* mux, TAG_ID id, uint nth,
WebPData* data) {
assert(mux != null);
memset(data, 0, sizeof(*data));
assert(!IsWPI(id));
SWITCH_ID_LIST(VP8X_ID, mux.vp8x_);
SWITCH_ID_LIST(ICCP_ID, mux.iccp_);
SWITCH_ID_LIST(LOOP_ID, mux.loop_);
SWITCH_ID_LIST(META_ID, mux.meta_);
SWITCH_ID_LIST(UNKNOWN_ID, mux.unknown_);
return WEBP_MUX_NOT_FOUND;
}
// Gets a reference to the nth tile from the mux object.
// The caller should NOT free the returned data.
// nth=0 has a special meaning - last position.
// Parameters:
// mux - (in) object from which the info is to be fetched
// nth - (in) index of the tile in the mux object
// image - (out) the image data
// alpha - (out) the alpha data corresponding to tile image (if present)
// x_offset - (out) x-offset of the returned tile
// y_offset - (out) y-offset of the returned tile
// Returns:
// WEBP_MUX_INVALID_ARGUMENT - if either mux, image, x_offset or
// y_offset is null
// WEBP_MUX_NOT_FOUND - if there are less than nth tiles in the mux object.
// WEBP_MUX_BAD_DATA - if nth tile chunk in mux is invalid.
// WEBP_MUX_OK - on success.
WebPMuxError WebPMuxGetTile(WebPMux* mux, uint nth, WebPData* image, WebPData* alpha, uint* x_offset, uint* y_offset) {
return MuxGetFrameTileInternal(mux, nth, image, alpha,
x_offset, y_offset, null,
kChunks[TILE_ID].chunkTag);
}
// Gets a reference to the nth animation frame from the mux object.
// The caller should NOT free the returned data.
// nth=0 has a special meaning - last position.
// Parameters:
// mux - (in) object from which the info is to be fetched
// nth - (in) index of the frame in the mux object
// image - (out) the image data
// alpha - (out) the alpha data corresponding to frame image (if present)
// x_offset - (out) x-offset of the returned frame
// y_offset - (out) y-offset of the returned frame
// duration - (out) duration of the returned frame (in milliseconds)
// Returns:
// WEBP_MUX_INVALID_ARGUMENT - if either mux, image, x_offset,
// y_offset, or duration is null
// WEBP_MUX_NOT_FOUND - if there are less than nth frames in the mux object.
// WEBP_MUX_BAD_DATA - if nth frame chunk in mux is invalid.
// WEBP_MUX_OK - on success.
WebPMuxError WebPMuxGetFrame(WebPMux* mux, uint nth, WebPData* image, WebPData* alpha, uint* x_offset, uint* y_offset, uint* duration) {
return MuxGetFrameTileInternal(mux, nth, image, alpha,
x_offset, y_offset, duration,
kChunks[FRAME_ID].chunkTag);
}
static WebPMuxError MuxGetFrameTileInternal(WebPMux* mux,
uint nth,
WebPData* image,
WebPData* alpha,
uint* x_offset,
uint* y_offset,
uint* duration, uint tag) {
byte* frame_tile_data;
uint frame_tile_size;
WebPMuxError err;
WebPMuxImage* wpi;
int is_frame = (tag == kChunks[FRAME_ID].chunkTag) ? 1 : 0;
TAG_ID id = is_frame ? FRAME_ID : TILE_ID;
if (mux == null || image == null ||
x_offset == null || y_offset == null || (is_frame && duration == null)) {
return WEBP_MUX_INVALID_ARGUMENT;
}
// Get the nth WebPMuxImage.
err = MuxImageGetNth((WebPMuxImage**)&mux.images_, nth, id, &wpi);
if (err != WEBP_MUX_OK) return err;
// Get frame chunk.
assert(wpi.header_ != null); // As GetNthImage() already checked header_.
frame_tile_data = wpi.header_.data_;
frame_tile_size = wpi.header_.payload_size_;
if (frame_tile_size < kChunks[id].chunkSize) return WEBP_MUX_BAD_DATA;
*x_offset = GetLE32(frame_tile_data + 0);
*y_offset = GetLE32(frame_tile_data + 4);
if (is_frame) *duration = GetLE32(frame_tile_data + 16);
// Get alpha chunk (if present & requested).
if (alpha != null) {
memset(alpha, 0, sizeof(*alpha));
if (wpi.alpha_ != null) {
alpha.bytes_ = wpi.alpha_.data_;
alpha.size_ = wpi.alpha_.payload_size_;
}
}
// Get image chunk.
memset(image, 0, sizeof(*image));
if (wpi.vp8_ != null) {
image.bytes_ = wpi.vp8_.data_;
image.size_ = wpi.vp8_.payload_size_;
}
return WEBP_MUX_OK;
}
// Gets a reference to the color profile in the mux object.
// The caller should NOT free the returned data.
// Parameters:
// mux - (in) object from which the color profile data is to be fetched
// color_profile - (out) color profile data
// Returns:
// WEBP_MUX_INVALID_ARGUMENT - if either mux or color_profile is null.
// WEBP_MUX_NOT_FOUND - if color profile is not present in mux object.
// WEBP_MUX_OK - on success.
WebPMuxError WebPMuxGetColorProfile(WebPMux* mux,
WebPData* color_profile) {
if (mux == null || color_profile == null) {
return WEBP_MUX_INVALID_ARGUMENT;
}
return MuxGet(mux, ICCP_ID, 1, color_profile);
}
// Gets a reference to the XMP metadata in the mux object.
// The caller should NOT free the returned data.
// Parameters:
// mux - (in) object from which the XMP metadata is to be fetched
// metadata - (out) XMP metadata
// Returns:
// WEBP_MUX_INVALID_ARGUMENT - if either mux or metadata is null.
// WEBP_MUX_NOT_FOUND - if metadata is not present in mux object.
// WEBP_MUX_OK - on success.
public WebPMuxError WebPMuxGetMetadata(WebPMux* mux, WebPData* metadata) {
if (mux == null || metadata == null) {
return WEBP_MUX_INVALID_ARGUMENT;
}
return MuxGet(mux, META_ID, 1, metadata);
}
// Gets a reference to the image in the mux object.
// The caller should NOT free the returned data.
// Parameters:
// mux - (in) object from which the image is to be fetched
// image - (out) the image data
// alpha - (out) the alpha data of the image (if present)
// Returns:
// WEBP_MUX_INVALID_ARGUMENT - if either mux or image is null
// OR if mux contains animation/tiling.
// WEBP_MUX_NOT_FOUND - if image is not present in mux object.
// WEBP_MUX_OK - on success.
public WebPMuxError WebPMuxGetImage(WebPMux* mux, WebPData* image, WebPData* alpha) {
WebPMuxError err;
WebPMuxImage* wpi = null;
if (mux == null || image == null) {
return WEBP_MUX_INVALID_ARGUMENT;
}
memset(image, 0, sizeof(*image));
err = ValidateForImage(mux);
if (err != WEBP_MUX_OK) return err;
// All well. Get the image.
err = MuxImageGetNth((WebPMuxImage**)&mux.images_, 1, IMAGE_ID, &wpi);
assert(err == WEBP_MUX_OK); // Already tested above.
// Get alpha chunk (if present & requested).
if (alpha != null) {
memset(alpha, 0, sizeof(*alpha));
if (wpi.alpha_ != null) {
alpha.bytes_ = wpi.alpha_.data_;
alpha.size_ = wpi.alpha_.payload_size_;
}
}
// Get image chunk.
if (wpi.vp8_ != null) {
image.bytes_ = wpi.vp8_.data_;
image.size_ = wpi.vp8_.payload_size_;
}
return WEBP_MUX_OK;
}
// Outputs image data given data from a webp file (including RIFF header).
static WebPMuxError GetImageData(byte* data, uint size, WebPData* image, WebPData* alpha)
{
if (size < TAG_SIZE || memcmp(data, "RIFF", TAG_SIZE)) {
// It is NOT webp file data. Return input data as is.
image.bytes_ = data;
image.size_ = size;
return WEBP_MUX_OK;
} else {
// It is webp file data. Extract image data from it.
WebPMuxError err;
WebPMuxState mux_state;
WebPMux* mux = WebPMuxCreate(data, size, 0, &mux_state);
if (mux == null || mux_state != WEBP_MUX_STATE_COMPLETE) {
return WEBP_MUX_BAD_DATA;
}
err = WebPMuxGetImage(mux, image, alpha);
WebPMuxDelete(mux);
return err;
}
}
