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// 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_H_
#define WEBP_DEC_ALPHAI_H_
#include "./webpi_dec.h"
#include "../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_H_ */