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enable lossless decoder

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import changes from experimental 5529a2e^
and enable build in autoconf and makefile.unix; windows will be treated
separately.

Change-Id: Ie2e177a99db63190b4cd647b3edee3b4e13719e9
This commit is contained in:
James Zern
2012-04-10 18:41:18 -07:00
parent b96efd7d50
commit f2623dbe58
8 changed files with 331 additions and 212 deletions
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70
src/dec/webpi.h
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@ -54,65 +54,25 @@ void WebPResetDecParams(WebPDecParams* const params);
#define VP8X_CHUNK_SIZE 12
#define VP8_FRAME_HEADER_SIZE 10 // Size of the frame header within VP8 data.
// Validates the RIFF container (if detected) and skips over it.
// If a RIFF container is detected,
// Returns VP8_STATUS_BITSTREAM_ERROR for invalid header, and
// VP8_STATUS_OK otherwise.
// In case there are not enough bytes (partial RIFF container), return 0 for
// riff_size. Else return the riff_size extracted from the header.
VP8StatusCode WebPParseRIFF(const uint8_t** data, uint32_t* data_size,
uint32_t* riff_size);
// Structure storing a description of the RIFF headers.
typedef struct {
const uint8_t* data; // input buffer
uint32_t data_size; // input buffer size
uint32_t offset; // offset to main data chunk (VP8 or VP8L)
const uint8_t* alpha_data; // points to alpha chunk (if present)
uint32_t alpha_data_size; // alpha chunk size
uint32_t vp8_size; // vp8 compressed data size
uint32_t riff_size; // size of the riff payload (or 0 if absent)
int is_lossless; // true if a VP8L chunk is present
} WebPHeaderStructure;
// Validates the VP8X Header and skips over it.
// Returns VP8_STATUS_BITSTREAM_ERROR for invalid VP8X header,
// VP8_STATUS_NOT_ENOUGH_DATA in case of insufficient data, and
// VP8_STATUS_OK otherwise.
// If a VP8 chunk is found, bytes_skipped is set to the total number of bytes
// that are skipped; also Width, Height & Flags are set to the corresponding
// fields extracted from the VP8X chunk.
VP8StatusCode WebPParseVP8X(const uint8_t** data, uint32_t* data_size,
uint32_t* bytes_skipped,
int* width, int* height, uint32_t* flags);
// Skips to the next VP8 chunk header in the data given the size of the RIFF
// chunk 'riff_size'.
// Returns VP8_STATUS_BITSTREAM_ERROR if any invalid chunk size is encountered,
// VP8_STATUS_NOT_ENOUGH_DATA in case of insufficient data, and
// VP8_STATUS_OK otherwise.
// If a VP8 chunk is found, bytes_skipped is set to the total number of bytes
// that are skipped. Also, if an alpha chunk is found, alpha_data and alpha_size
// are set appropriately.
VP8StatusCode WebPParseOptionalChunks(const uint8_t** data, uint32_t* data_size,
uint32_t riff_size,
uint32_t* bytes_skipped,
const uint8_t** alpha_data,
uint32_t* alpha_size);
// Validates the VP8 Header ("VP8 nnnn") and skips over it.
// Returns VP8_STATUS_BITSTREAM_ERROR for invalid (vp8_chunk_size greater than
// riff_size) VP8 header,
// VP8_STATUS_NOT_ENOUGH_DATA in case of insufficient data, and
// VP8_STATUS_OK otherwise.
// If a VP8 chunk is found, bytes_skipped is set to the total number of bytes
// that are skipped and vp8_chunk_size is set to the corresponding size
// extracted from the VP8 chunk header.
// For a partial VP8 chunk, vp8_chunk_size is set to 0.
VP8StatusCode WebPParseVP8Header(const uint8_t** data, uint32_t* data_size,
uint32_t riff_size, uint32_t* bytes_skipped,
uint32_t* vp8_chunk_size);
// Skips over all valid chunks prior to the first VP8 frame header.
// Skips over all valid chunks prior to the first VP8/VP8L frame header.
// Returns VP8_STATUS_OK on success,
// VP8_STATUS_BITSTREAM_ERROR if an invalid header/chunk is found, and
// VP8_STATUS_NOT_ENOUGH_DATA if case of insufficient data.
// Also, data, data_size, vp8_size, bytes_skipped, alpha_data & alpha_size are
// updated appropriately on success, where
// vp8_size is the size of VP8 chunk data (extracted from VP8 chunk header) and
// bytes_skipped is set to the total number of bytes that are skipped.
VP8StatusCode WebPParseHeaders(const uint8_t** data, uint32_t* data_size,
uint32_t* vp8_size, uint32_t* bytes_skipped,
const uint8_t** alpha_data,
uint32_t* alpha_size);
// In 'headers', vp8_size, offset, alpha_data, alpha_size and lossless fields
// are updated appropriately upon success.
VP8StatusCode WebPParseHeaders(WebPHeaderStructure* const headers);
//------------------------------------------------------------------------------
// Misc utils