// Copyright 2013 Google Inc. All Rights Reserved.

//

// Use of this source code is governed by a BSD-style license

// that can be found in the COPYING file in the root of the source

// tree. An additional intellectual property rights grant can be found

// in the file PATENTS. All contributing project authors may

// be found in the AUTHORS file in the root of the source tree.

// -----------------------------------------------------------------------------

//

// Alpha decoder: internal header.

//

// Author: Urvang (urvang@google.com)

#ifndef WEBP_DEC_ALPHAI_DEC_H_

#define WEBP_DEC_ALPHAI_DEC_H_

#include "src/dec/webpi_dec.h"

#include "src/utils/filters_utils.h"

#ifdef __cplusplus

extern "C" {

#endif

struct VP8LDecoder;  // Defined in dec/vp8li.h.

typedef struct ALPHDecoder ALPHDecoder;

struct ALPHDecoder {

  int width_;

  int height_;

  int method_;

  WEBP_FILTER_TYPE filter_;

  int pre_processing_;

  struct VP8LDecoder* vp8l_dec_;

  VP8Io io_;

  int use_8b_decode_;  // Although alpha channel requires only 1 byte per

                       // pixel, sometimes VP8LDecoder may need to allocate

                       // 4 bytes per pixel internally during decode.

  uint8_t* output_;

  const uint8_t* prev_line_;   // last output row (or NULL)

};

//------------------------------------------------------------------------------

// internal functions. Not public.

// Deallocate memory associated to dec->alpha_plane_ decoding

void WebPDeallocateAlphaMemory(VP8Decoder* const dec);

//------------------------------------------------------------------------------

#ifdef __cplusplus

}    // extern "C"

#endif

#endif  /* WEBP_DEC_ALPHAI_DEC_H_ */