1 /*
2  * Copyright (c) 2011 Apple Inc. All rights reserved.
3  *
4  * @APPLE_APACHE_LICENSE_HEADER_START@
5  *
6  * Licensed under the Apache License, Version 2.0 (the "License");
7  * you may not use this file except in compliance with the License.
8  * You may obtain a copy of the License at
9  *
10  *     http://www.apache.org/licenses/LICENSE-2.0
11  *
12  * Unless required by applicable law or agreed to in writing, software
13  * distributed under the License is distributed on an "AS IS" BASIS,
14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15  * See the License for the specific language governing permissions and
16  * limitations under the License.
17  *
18  * @APPLE_APACHE_LICENSE_HEADER_END@
19  */
20 
21 /*
22 	File:		ALACDecoder.h
23 */
24 
25 #ifndef _ALACDECODER_H
26 #define _ALACDECODER_H
27 
28 #if PRAGMA_ONCE
29 #pragma once
30 #endif
31 
32 #include <stdint.h>
33 
34 #include "ALACAudioTypes.h"
35 
36 struct BitBuffer;
37 
38 class ALACDecoder
39 {
40 	public:
41 		ALACDecoder();
42 		~ALACDecoder();
43 
44 		int32_t	Init( void * inMagicCookie, uint32_t inMagicCookieSize );
45 		int32_t	Decode( struct BitBuffer * bits, uint8_t * sampleBuffer, uint32_t numSamples, uint32_t numChannels, uint32_t * outNumSamples );
46 
47 	public:
48 		// decoding parameters (public for use in the analyzer)
49 		ALACSpecificConfig		mConfig;
50 
51 	protected:
52 		int32_t	FillElement( struct BitBuffer * bits );
53 		int32_t	DataStreamElement( struct BitBuffer * bits );
54 
55 		uint16_t					mActiveElements;
56 
57 		// decoding buffers
58 		int32_t *				mMixBufferU;
59 		int32_t *				mMixBufferV;
60 		int32_t *				mPredictor;
61 		uint16_t *				mShiftBuffer;	// note: this points to mPredictor's memory but different
62 												//		 variable for clarity and type difference
63 };
64 
65 #endif	/* _ALACDECODER_H */
66