shoutcaststream.h

这是一个使用 ShortCast的IP网络流式播放的symbian的软件源码.里面有ShortCast短播协议的实现以及AAC音频,MP3音频流式播放的实现.

/*
* ==============================================================================
*  Name        : ShoutcastStream.h
*  Part of     : Shoutcast Engine
*  Interface   :
*  Description : Defines the shoutcast stream class of the shoutcast engine.
*  Version     : 2
*
*  Copyright (c) 2006, Nokia Corporation All rights reserved. Redistribution
*  and use in source and binary forms, with or without modification, are
*  permitted provided that the following conditions are met: Redistributions
*  of source code must retain the above copyright notice, this list of
*  conditions and the following disclaimer. Redistributions in binary form
*  must reproduce the above copyright notice, this list of conditions and the
*  following disclaimer in the documentation and/or other materials provided
*  with the distribution. Neither the name of the Nokia Corporation nor the
*  names of its contributors may be used to endorse or promote products
*  derived from this software without specific prior written permission. THIS
*  SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
*  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
*  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
*  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
*  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
*  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
*  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
*  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
*  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
*  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
*  POSSIBILITY OF SUCH DAMAGE.
* ==============================================================================
*/

#ifndef __SHOUTCASTSTREAM_H
#define __SHOUTCASTSTREAM_H

// INCLUDE FILES
#include <e32std.h>
#include <es_sock.h>
#include <in_sock.h>
#include <mda\common\audio.h>
#include <MdaAudioOutputStream.h>

#if RELEASE_LOG
#include <flogger.h>
#endif

#include "MShoutcastStreamObserver.h"
#include "ScMetadata.h"

// FORWARD DECLARATIONS
class CEventDispatcher;

// CLASS DECLARATION

/**
*  Frame info structure.
*/
class TAudioFrameInfo
    {
	public:
		TInt iMode;            // encoding mode
		TInt iBitRate;         // bitrate (bit/s)
		TInt iSamplingRate;    // sampling frequency (Hz)
		TInt iChannels;        // number of channels
		TInt iFrameSize;       // encoded size (bytes)
		TInt iFrameSamples;    // decoded size (samples per channel)

		TInt iSamplingRateOut; // sampling frequency after conversion (Hz)
		TInt iChannelsOut;     // number of audio channels after conversion (1 or 2)
		TInt iFrameSamplesOut; // decoded size after conversion (samples per channel)
		TInt iPadding;         // padding flag (TRUE or FALSE, TRUE if p slot exists)
		TInt iId;              // id of algorithm (1 MPEG-1, 0 MPEG-2)
    };


/**
*  This class is the heart of the shoutcast engine. It handles the shoutcast protocol,
*  interfaces to the audio stream player, and extracts metadata from the data stream.
*
*/
class CShoutcastStream : public CActive,
						 public MMdaAudioOutputStreamCallback
	{
	//instantiation

	public: // Contructors

        /**
        * Create a CShoutcastStream object
        * @param aUrl The URL of the stream
        * @param aObserver The observer of the shoutcast stream object
        * @return pointer to new object
        */
		static CShoutcastStream* NewL(const TDesC8& aUrl, MShoutcastStreamObserver& aObserver);

        /**
        * Destructor.
        */
    	~CShoutcastStream();

    public: // New functions

		void CloseAndClean();

        /**
        * Get the requested meta data entry
        * @return the requested meta data entry
        */
		CMetaDataEntry* GetMetaDataEntryL(TInt aIndex);

		/**
        * Get the number of metadata entries
        * @return number of metadata entries
        */
		TInt GetNumberOfMetaDataEntries();

        /**
        * Get the maximum volume level
        * @return Maximum Volume Level
        */
		TInt MaxVolume();

		/**
        * Preparing the stream and allocates resources.
        */
        void PrimeL();

		/**
        * Start the play process and moving data to the stream output.
        */
		void PlayL();

		/**
        * Pauses the play process.
        */
        void Pause();

		/**
        * Terminate the play process
        */
        void Stop();

		/**
        * Set the volume
        * @param aVolume The desired volume level
        */
        void SetVolume(TInt aVolume);

        /**
        * Get the current volume level
        * @return Volume Level
        */
		TInt Volume();

    public: // from MMdaAudioOutputStreamCallback

		/**
        * Called when CMdaAudioOutputStream::Open() has completed,
		* indicating that the audio output stream is ready for use.
        * @param aError An error value which indicates if open was completed successfully.
        * KErrNone if succeeded
        */
		virtual void MaoscOpenComplete(TInt aError);

		/**
        * Called when the descriptor has been copied.
        * @param aError KErrNone if the copy succeeded, otherwise one of the system
        * error codes. KErrAbort indicates that the client has stopped the stream playing
        * before the descriptor has been copied.
        */
		virtual void MaoscBufferCopied(TInt aError, const TDesC8& aBuffer);

		/**
        * Called when playback terminates as a result of a CMdaAudioOutputStream::Stop().
        * @param aError An error value which indicates play success or not. KErrNone if
        * the close succeeded, otherwise one of the system error codes.
        */
		virtual void MaoscPlayComplete(TInt aError);

	private:

        /**
        * C++ default constructor.
		*/
		CShoutcastStream();

        /**
        * By default Symbian 2nd phase constructor is private.
        * @param aUrl The URL of the stream
        * @param aObserver The observer of the shoutcast stream
        */
		void ConstructL(const TDesC8& aUrl, MShoutcastStreamObserver& aObserver);

        /**
        * Fill the play buffer
        */
        void FillBufferL();

		// from CActive
		void DoCancel();
		void RunL();
		TInt RunError(TInt aError);

        /**
        * Parse the URL and extracts the IP address
        */
        void GetIPFromURL();

        /**
        * Remove any metadata from the buffer
        */
		void RemoveMetadata(TDes8& ptrMetadata);

        /**
        * Retreive and remove any metadata from the buffer
        */
		void GetAndRemoveMetadata(TUint8 *aBuf,TInt &aLength);

        /**
        * Establish connection to the server
        * @param aReconnecting Indicates whether this is a reconnection or new connection
        */
		void ConnectToServerL(TBool aReconnecting = EFalse);

        /**
        * Send a request to the server
        */
		void SendRequestToServerL();

        /**
        * Receive response from the server
        */
		void ReceiveResponseFromServerL();

        /**
        * Parse response from the server
        */
		void ParseResponseFromServerL();

        /**
        * Parse response from the server
        */
		void InitStreamOutputL();

        /**
        * Reset buffer variables
        */
		void ResetBufferVars();

        /**
        * Request to read data from buffer
        */
		void ReadRequest();

        /**
        * Done reading data
        */
		TInt ReadRequestDone(TInt aRequested,TInt aRead);

        /**
        * Request more data from the network
        */
		void ReadRequestHelper();

        /**
        * Data is ready for reading
        */
		TInt ReadRequestHelperDone();

       /**
        * Disconnected from server
        * @param aError The error code
        */
		void Disconnect(TInt aError);

        /**
		* Scans the header to extract encoding data.
		* @param aBuf the buffer to be scanned
		* @param aLength length of the buffer.
		* @return ETrue if sucessfull, otherwise, EFalse.
        */
		TInt ScanHeader(TUint8 *aBuf, TInt aLength);

        /**
		* Returns the byte position of the first frame.
		* @param aBuf the buffer to be scanned
		* @param aLength length of the buffer.
		* @return byte position of the first frame
        */
		TInt Mp3SeekSync(TUint8 *aBuf, TInt aLength);

        /**
		* Returns the byte position of the first frame.
		* @param aBuf the buffer to be scanned
		* @param aLength length of the buffer.
		* @return byte position of the first frame
        */
		TInt AacSeekSync(TUint8 *aBuf, TInt aLength);

        /**
        * Test if the pointer points to a valid AAC frame
        * @param aPtr Pointer to the presumed frame
		* @param aBufLen Length of the data
        * @return Length of the buffer
        */
        TBool IsValidAacFrame( const TUint8* aPtr, TInt aBufLen );

		/**
		* Returns frame info.
		* @param aBuf Pointer to the data
		* @param aBufLen Length of the data
		* @param aInfo Contains the frame info on return
		* @return frame length
		*/
		TInt GetMp3FrameInfo( const TUint8* aBuf, TInt aBufLen, TAudioFrameInfo& aInfo );

		/**
		* Returns frame info.
		* @param aBuf Pointer to the data
		* @param aBufLen Length of the data
		* @param aInfo Contains the frame info on return
		* @return frame length
		*/
		TInt GetAacFrameInfo( const TUint8* aBuf, TInt aBufLen, TAudioFrameInfo& aInfo );

        /**
		* Get audio settings from the audio stream.
        */
        void GetAudioSettings();

        /**
		* Derive audio settings from data received from the server.
        */
		void DeriveAudioSettings();


	private: // Data

		// Engine States
		enum TState
			{
			ENotConnected,
			EResolving,
			EConnecting,
			ESendingRequest,
			EReceivingResponse,
			EAnswerOK,
			EAnswerError,
			EInitMP3Dec,
			EInitStreamOutput,
			EData,
			EDisconnecting
			};

		// Current engine state
		TState iState;
		// Event dispatcher
		CEventDispatcher* iDispatcher;
		// Output Stream object
		CMdaAudioOutputStream* iStreamOutput;
		// Settings for audio stream (but not used)
		TMdaAudioDataSettings iSettings;

		// Sampling rate found in header
		TInt iSamplingRate;
		// Bit rate (bps) found in header
		TInt iBitRate;
		// Number of channels found in header
		TInt iChannels;

		// Buffers for url parsing
		TBuf8<URL_SIZE> iURL;
		TBuf8<URL_SIZE> iPath;
		TBuf8<URL_SIZE> iIp;

		// stream buffering related
		TUint8 *iBuffer2Decode;
		TUint8 *iBuffer2Play;
		TPtr8 iPtrBuffer2Decode;
		TPtr8 iPtrBuffer2Play;

		TInt iLenBuffer2Decode;
		TInt iLenBuffer2Play;
		TInt iPosBuffer2Decode;
		TInt iReadData;
		TBool iReadingActive;
		//for accounting and displaying
		TInt iTotalBytesReceived;
		//nr of hundred of KBytes
		TInt iNrHKB;
		TInt iRRreq,iRRread;
		//bitrate
		TInt iBitrate;
		TInt iInstantBitrate;
		TTime iLastReading;
		RArray<TInt> iBitsRead;
		RArray<TInt64> iTimeIntervals;
		TBool iWritingToStream;
		TBool iPausedForBuffering;

		TInt iMaxFrameSize;
		TInt iVolume;

		//MetaData related
		TInt iMetaint;
		TInt iCnt;
		TInt iDataSeen;
		RPointerArray<CMetaDataEntry> iMetadata;
		TBuf<METADATA_BUFFER_SIZE> iTempMetadata;
		TUint8 *iMetadataBuffer;
		TMdaAudioDataSettings iAudioSettings;
		TFourCC iDataType;

		// Networking related
		TInetAddr* iAddr;
		RSocketServ iSocksvr;
		RSocket iSock;

	#if RELEASE_LOG
		RFileLogger iLog;
	#endif

	};


#endif // __SHOUTCASTSTREAM_H

// End of file