//
//  SKAudio.h
//  SpeechKit
//
// Copyright 2010, Nuance Communications Inc. All rights reserved.
//
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// or warranty of any kind. The information in this document is subject to
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//

#import <Foundation/Foundation.h>

typedef NS_ENUM(NSInteger, SKPCMSampleFormat) {
    SKPCMSampleFormatSignedLinear16, // Linear, signed, 16-bit samples
};


/*!
 @abstract Description of format of PCM audio.
 */
@interface SKPCMFormat : NSObject

/*!
 @abstract Sampling rate of audio in Hz
 */
@property (assign) float sampleRate;
/*!
 @abstract Number of channels, assumed to be interleaved.
 */
@property (assign) int channels;
/*!
 @abstract Encoding of each sample, assumed to be little-endian.
 */
@property (assign) SKPCMSampleFormat sampleFormat;

@end
/*!
 @abstract The SKAudio class contains audio data for use with SKAudioPlayer.
 */
@interface SKAudio : NSObject

@end

/*!
 @abstract The SKAudioFile class represents an audio file from disk.
 
 @discussion This class is usually used to load user provided earcons.  The transaction delegate may however provide an SKAudioFile instance instead of an SKSynthesizedAudio instance in transaction:didReceiveAudio: for non-traditional TTS responses or service specific responses.
 */
@interface SKAudioFile : SKAudio
/*!
 @abstract Initializes with audio from a URL.
 
 @discussion Right now only single-channel, 16kHz, 16-bit signed linear PCM is accepted.
 */
- (instancetype)initWithURL:(NSURL *)url pcmFormat:(SKPCMFormat*)pcmFormat;

@end