| // 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.h" |
| #include "../utils/filters.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. |
| }; |
| |
| //------------------------------------------------------------------------------ |
| // internal functions. Not public. |
| |
| // Allocates a new alpha decoder instance. |
| ALPHDecoder* ALPHNew(void); |
| |
| // Clears and deallocates an alpha decoder instance. |
| void ALPHDelete(ALPHDecoder* const dec); |
| |
| //------------------------------------------------------------------------------ |
| |
| #ifdef __cplusplus |
| } // extern "C" |
| #endif |
| |
| #endif /* WEBP_DEC_ALPHAI_H_ */ |