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Mux API change:

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Create common APIs for image, frame and tile.

Change-Id: I709ad752133094bd5bc89dd9c832ff79802aac68
This commit is contained in:
Urvang Joshi
2012-08-23 16:28:36 +05:30
parent c6e98658d2
commit d0c79f0552
7 changed files with 286 additions and 443 deletions
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121
src/mux/muxread.c
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@ -190,6 +190,8 @@ WebPMux* WebPMuxCreateInternal(const WebPData* bitstream, int copy_data,
//------------------------------------------------------------------------------
// Get API(s).
// TODO(urvang): Change the behavior of this to return ALPHA_FLAG when the mux
// doesn't contain a VP8X chunk, but does contain a VP8L chunk with real alpha.
WebPMuxError WebPMuxGetFeatures(const WebPMux* mux, uint32_t* flags) {
WebPData data;
WebPMuxError err;
@ -200,10 +202,7 @@ WebPMuxError WebPMuxGetFeatures(const WebPMux* mux, uint32_t* flags) {
// Check if VP8X chunk is present.
err = MuxGet(mux, IDX_VP8X, 1, &data);
if (err == WEBP_MUX_NOT_FOUND) {
// Check if VP8/VP8L chunk is present.
err = WebPMuxGetImage(mux, &data);
WebPDataClear(&data);
return err;
return MuxValidateForImage(mux); // Check if a single image is present.
} else if (err != WEBP_MUX_OK) {
return err;
}
@ -230,7 +229,7 @@ static uint8_t* EmitVP8XChunk(uint8_t* const dst, int width,
}
// Assemble a single image WebP bitstream from 'wpi'.
static WebPMuxError SynthesizeBitstream(WebPMuxImage* const wpi,
static WebPMuxError SynthesizeBitstream(const WebPMuxImage* const wpi,
WebPData* const bitstream) {
uint8_t* dst;
@ -270,25 +269,6 @@ static WebPMuxError SynthesizeBitstream(WebPMuxImage* const wpi,
return WEBP_MUX_OK;
}
WebPMuxError WebPMuxGetImage(const WebPMux* mux, WebPData* bitstream) {
WebPMuxError err;
WebPMuxImage* wpi = NULL;
if (mux == NULL || bitstream == NULL) {
return WEBP_MUX_INVALID_ARGUMENT;
}
err = MuxValidateForImage(mux);
if (err != WEBP_MUX_OK) return err;
// All well. Get the image.
err = MuxImageGetNth((const WebPMuxImage**)&mux->images_, 1, WEBP_CHUNK_IMAGE,
&wpi);
assert(err == WEBP_MUX_OK); // Already tested above.
return SynthesizeBitstream(wpi, bitstream);
}
WebPMuxError WebPMuxGetChunk(const WebPMux* mux, const char fourcc[4],
WebPData* chunk_data) {
const CHUNK_INDEX idx = ChunkGetIndexFromFourCC(fourcc);
@ -306,6 +286,56 @@ WebPMuxError WebPMuxGetChunk(const WebPMux* mux, const char fourcc[4],
}
}
static WebPMuxError MuxGetImageInternal(const WebPMuxImage* const wpi,
WebPMuxFrameInfo* const info) {
// Set some defaults for unrelated fields.
info->x_offset_ = 0;
info->y_offset_ = 0;
info->duration_ = 1;
// Extract data for related fields.
info->id = ChunkGetIdFromTag(wpi->img_->tag_);
return SynthesizeBitstream(wpi, &info->bitstream_);
}
static WebPMuxError MuxGetFrameTileInternal(const WebPMuxImage* const wpi,
WebPMuxFrameInfo* const frame) {
const int is_frame = (wpi->header_->tag_ == kChunks[IDX_FRAME].tag);
const CHUNK_INDEX idx = is_frame ? IDX_FRAME : IDX_TILE;
const WebPData* frame_tile_data;
assert(wpi->header_ != NULL); // Already checked by WebPMuxGetFrame().
// Get frame/tile chunk.
frame_tile_data = &wpi->header_->data_;
if (frame_tile_data->size_ < kChunks[idx].size) return WEBP_MUX_BAD_DATA;
// Extract info.
frame->x_offset_ = 2 * GetLE24(frame_tile_data->bytes_ + 0);
frame->y_offset_ = 2 * GetLE24(frame_tile_data->bytes_ + 3);
frame->duration_ = is_frame ? 1 + GetLE24(frame_tile_data->bytes_ + 12) : 1;
frame->id = ChunkGetIdFromTag(wpi->header_->tag_);
return SynthesizeBitstream(wpi, &frame->bitstream_);
}
WebPMuxError WebPMuxGetFrame(
const WebPMux* mux, uint32_t nth, WebPMuxFrameInfo* frame) {
WebPMuxError err;
WebPMuxImage* wpi;
// Sanity checks.
if (mux == NULL || frame == NULL) {
return WEBP_MUX_INVALID_ARGUMENT;
}
// Get the nth WebPMuxImage.
err = MuxImageGetNth((const WebPMuxImage**)&mux->images_, nth, &wpi);
if (err != WEBP_MUX_OK) return err;
// Get frame info.
if (wpi->header_ == NULL) {
return MuxGetImageInternal(wpi, frame);
} else {
return MuxGetFrameTileInternal(wpi, frame);
}
}
WebPMuxError WebPMuxGetLoopCount(const WebPMux* mux, int* loop_count) {
WebPData image;
WebPMuxError err;
@ -320,49 +350,6 @@ WebPMuxError WebPMuxGetLoopCount(const WebPMux* mux, int* loop_count) {
return WEBP_MUX_OK;
}
static WebPMuxError MuxGetFrameTileInternal(
const WebPMux* const mux, uint32_t nth,
WebPMuxFrameInfo* const frame_tile_info, uint32_t tag) {
const WebPData* frame_tile_data;
WebPMuxError err;
WebPMuxImage* wpi;
const int is_frame = (tag == kChunks[WEBP_CHUNK_FRAME].tag) ? 1 : 0;
const CHUNK_INDEX idx = is_frame ? IDX_FRAME : IDX_TILE;
const WebPChunkId id = kChunks[idx].id;
if (mux == NULL || frame_tile_info == NULL) {
return WEBP_MUX_INVALID_ARGUMENT;
}
// Get the nth WebPMuxImage.
err = MuxImageGetNth((const WebPMuxImage**)&mux->images_, nth, id, &wpi);
if (err != WEBP_MUX_OK) return err;
// Get frame chunk.
assert(wpi->header_ != NULL); // As MuxImageGetNth() already checked header_.
frame_tile_data = &wpi->header_->data_;
if (frame_tile_data->size_ < kChunks[idx].size) return WEBP_MUX_BAD_DATA;
frame_tile_info->x_offset_ = 2 * GetLE24(frame_tile_data->bytes_ + 0);
frame_tile_info->y_offset_ = 2 * GetLE24(frame_tile_data->bytes_ + 3);
if (is_frame) {
frame_tile_info->duration_ = 1 + GetLE24(frame_tile_data->bytes_ + 12);
}
return SynthesizeBitstream(wpi, &frame_tile_info->bitstream_);
}
WebPMuxError WebPMuxGetFrame(const WebPMux* mux, uint32_t nth,
WebPMuxFrameInfo* frame) {
return MuxGetFrameTileInternal(mux, nth, frame, kChunks[IDX_FRAME].tag);
}
WebPMuxError WebPMuxGetTile(const WebPMux* mux, uint32_t nth,
WebPMuxFrameInfo* tile) {
return MuxGetFrameTileInternal(mux, nth, tile, kChunks[IDX_TILE].tag);
}
// Get chunk index from chunk id. Returns IDX_NIL if not found.
static CHUNK_INDEX ChunkGetIndexFromId(WebPChunkId id) {
int i;