Add WebP library to Chromium...

third_party/libwebp/webp/decode_vp8.h

+// 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_