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Diffstat (limited to 'third_party/libwebp/webp/decode_vp8.h')
-rw-r--r-- | third_party/libwebp/webp/decode_vp8.h | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/third_party/libwebp/webp/decode_vp8.h b/third_party/libwebp/webp/decode_vp8.h new file mode 100644 index 0000000..6ac9fc5 --- /dev/null +++ b/third_party/libwebp/webp/decode_vp8.h @@ -0,0 +1,107 @@ +// Copyright 2010 Google Inc. +// +// This code is licensed under the same terms as WebM: +// Software License Agreement: http://www.webmproject.org/license/software/ +// Additional IP Rights Grant: http://www.webmproject.org/license/additional/ +// ----------------------------------------------------------------------------- +// +// Low-level API for VP8 decoder +// +// Author: Skal (pascal.massimino@gmail.com) + +#ifndef WEBP_DECODE_WEBP_DECODE_VP8_H_ +#define WEBP_DECODE_WEBP_DECODE_VP8_H_ + +#include "decode.h" + +#if defined(__cplusplus) || defined(c_plusplus) +extern "C" { +#endif + +//----------------------------------------------------------------------------- +// Lower-level API +// +// Thes functions provide fine-grained control of the decoding process. +// The call flow should resemble: +// +// VP8Io io; +// VP8InitIo(&io); +// io.data = data; +// io.data_size = size; +// /* customize io's functions (setup()/put()/teardown()) if needed. */ +// +// VP8Decoder* dec = VP8New(); +// bool ok = VP8Decode(dec); +// if (!ok) printf("Error: %s\n", VP8StatusMessage(dec)); +// VP8Delete(dec); +// return ok; + +// Input / Output +typedef struct VP8Io VP8Io; +struct VP8Io { + // set by VP8GetHeaders() + int width, height; // picture dimensions, in pixels + + // set before calling put() + int mb_x, mb_y; // position of the current sample (in pixels) + int mb_w, mb_h; // size of the current sample (usually 16x16) + const uint8_t *y, *u, *v; // samples to copy + int y_stride; // stride for luma + int uv_stride; // stride for chroma + + void* opaque; // user data + + // called when fresh samples are available (1 block of 16x16 pixels) + void (*put)(const VP8Io* io); + + // called just before starting to decode the blocks + void (*setup)(const VP8Io* io); + + // called just after block decoding is finished + void (*teardown)(const VP8Io* io); + + // Input buffer. + uint32_t data_size; + const uint8_t* data; +}; + +// Main decoding object. This is an opaque structure. +typedef struct VP8Decoder VP8Decoder; + +// Create a new decoder object. +VP8Decoder* VP8New(); + +// Can be called to make sure 'io' is initialized properly. +void VP8InitIo(VP8Io* const io); + +// Start decoding a new picture. Returns true if ok. +int VP8GetHeaders(VP8Decoder* const dec, VP8Io* const io); + +// Decode a picture. Will call VP8GetHeaders() if it wasn't done already. +int VP8Decode(VP8Decoder* const dec, VP8Io* const io); + +// Return current status of the decoder: +// 0 = OK +// 1 = OUT_OF_MEMORY +// 2 = INVALID_PARAM +// 3 = BITSTREAM_ERROR +// 4 = UNSUPPORTED_FEATURE +int VP8Status(VP8Decoder* const dec); + +// return readable string corresponding to the last status. +const char* VP8StatusMessage(VP8Decoder* const dec); + +// Resets the decoder in its initial state, reclaiming memory. +// Not a mandatory call between calls to VP8Decode(). +void VP8Clear(VP8Decoder* const dec); + +// Destroy the decoder object. +void VP8Delete(VP8Decoder* const dec); + +//----------------------------------------------------------------------------- + +#if defined(__cplusplus) || defined(c_plusplus) +} // extern "C" +#endif + +#endif // WEBP_DECODE_WEBP_DECODE_VP8_H_ |