1 /*

     2 * Copyright (c) 2010 Ixonos Plc.

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of the "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - Initial contribution

    11 *

    12 * Contributors:

    13 * Ixonos Plc

    14 *

    15 * Description:  

    16 *

    17 */

    18 

    19 

    20 

    21 #ifndef __CRateConverter_H__

    22 #define __CRateConverter_H__

    23 

    24 #include <e32base.h>

    25 

    26 #include "resampler_rate_conversion_input_driven_int16.h"

    27 

    28 class CRateConverter : public CBase

    29     {

    30 

    31 public:

    32     

    33     /*

    34     * Symbian constructors

    35     *

    36     */

    37     static CRateConverter* NewL(TInt aFromSampleRate, TInt aToSampleRate, TInt aFromChannels, TInt aToChannels);

    38                                         

    39     static CRateConverter* NewLC(TInt aFromSampleRate, TInt aToSampleRate, TInt aFromChannels, TInt aToChannels);

    40 

    41     /*

    42     * Destructor

    43     */

    44     ~CRateConverter();

    45     

    46     /*

    47     * Initialize the rate converter

    48     *

    49     * @param aInputBufferSize Max size of the input buffer in number of samples

    50     * @return ETrue if successful

    51     *

    52     */

    53     TBool InitL(TInt aInputBufferSize);

    54 

    55     /*

    56     * Does rate and channel conversion for given buffer

    57     *

    58     * @param aInput Pointer to input buffer (16-bit samples)

    59     * @param aOutput Pointer to output buffer (16-bit samples)

    60     * @param aInputSampleCount Number of samples in the input buffer

    61     * @return Number of samples in the output buffer

    62     */

    63     TInt ConvertBufferL(TInt16* aInput, TInt16* aOutput, TInt aInputSampleCount);  

    64     

    65     /*

    66     * Returns the size of the output buffer

    67     *

    68     */

    69     TInt GetOutputBufferSize() { return iOuputBlockSize; }

    70     

    71 

    72 protected:

    73     

    74     // constructL    

    75     void ConstructL();

    76     

    77     // C++ constructor

    78     CRateConverter(TInt aFromSampleRate, TInt aToSampleRate, TInt aFromChannels, TInt aToChannels);

    79     

    80 private:

    81     

    82     /*

    83     * Does internal initialization

    84     *

    85     */

    86     TBool DoInitL(TInt aInputBufferSize);

    87     

    88     /*

    89     * Does the actual conversion

    90     *

    91     */

    92     TInt DoConvertL(TInt16** aInput, TInt aInputSampleCount);

    93     

    94     /*

    95     * Returns pointer to the output buffer

    96     *

    97     */

    98     TInt16** GetOutputBuffer() { return iOutBuffer; }

    99           

   100 private:

   101 

   102     // Another converter incase two phase converting is needed

   103     CRateConverter* iChild;

   104 

   105     // The actual converter

   106     RESAMPLER_RateConversionInputDrivenInt16* iConverter;

   107     

   108     // Input data for rate converter

   109     TInt16** iInBuffer;

   110     

   111     // Output data from rate converter

   112     TInt16** iOutBuffer;

   113     

   114     // Temp buffer used by converter

   115     TInt8* iScratchBuffer;

   116 

   117     // Size of the input buffer

   118     TInt iInputBlockSize;

   119     

   120     // Size of the output buffer

   121     TInt iOuputBlockSize;

   122     

   123     // Number of channels used in converter

   124     TInt iChannels;

   125 

   126     // Samplerate to convert from

   127     TInt iFromSampleRate;

   128     

   129     // Samplerate to convert to

   130     TInt iToSampleRate;

   131     

   132     // Number of channels in input

   133     TInt iFromChannels;

   134     

   135     // Number of channels in output

   136     TInt iToChannels;

   137     };

   138 

   139 #endif