oss_dev.cpp

这是在PCA下的基于IPP库示例代码例子,在网上下了IPP的库之后,设置相关参数就可以编译该代码.

/*//////////////////////////////////////////////////////////////////////////////
//
//                  INTEL CORPORATION PROPRIETARY INFORMATION
//     This software is supplied under the terms of a license agreement or
//     nondisclosure agreement with Intel Corporation and may not be copied
//     or disclosed except in accordance with the terms of that agreement.
//          Copyright(c) 2003-2005 Intel Corporation. All Rights Reserved.
//
*/

//
//      This file contains class covering OSS Linux devices interface
//

#include "umc_defs.h"
#ifdef UMC_ENABLE_OSS_AUDIO_RENDER

#include <sys/soundcard.h>
#include "fcntl.h"
#include "oss_dev.h"
#include "vm_debug.h"

UMC::Status
UMC::OSSDev::Init(const vm_var32 uiBitsPerSample,
                  const vm_var32 uiNumOfChannels,
                  const vm_var32 uiFreq)
{
    UMC::Status umcRes = UMC_OK;

    if (UMC_OK == umcRes)
    {   umcRes = m_Device.Init(VM_STRING("/dev/dsp"), O_WRONLY);    }

    if (UMC_OK == umcRes)
    {
        m_uiBitsPerSample = uiBitsPerSample;
        m_uiNumOfChannels = uiNumOfChannels;
        m_uiFreq = uiFreq;
        umcRes = Reset();
    }

    if (UMC_OK == umcRes)
    {   vm_debug_trace(4, VM_STRING("OSSDev::Init OK\n"));  }
    else
    {   vm_debug_trace(7, VM_STRING("OSSDev::Init failed\n"));  }
    return umcRes;
}

UMC::Status
UMC::OSSDev::RenderData(vm_byte* pbData, vm_var32 uiDataSize)
{
    if (0x3 & uiDataSize)
    {
        vm_debug_trace(7, VM_STRING("OSSDev::RenderData data size misalignment: %d\n"),
                                                                    uiDataSize);
    }
    m_uiBytesPlayed += uiDataSize;

    return m_Device.Write(pbData, uiDataSize, NULL);
}

UMC::Status
UMC::OSSDev::SetBitsPerSample(const vm_var32 uiBitsPerSample)
{
    Status umcRes = UMC_OK;
    vm_var32 uiFormat;

    switch (uiBitsPerSample)
    {
    case 16:
        uiFormat = AFMT_S16_LE;
        break;
    case 8:
        uiFormat = AFMT_S8;
        break;
    default:
        vm_debug_trace(7,
            VM_STRING("OSSDev::SetBitsPerSample - unsupported: %dbps requested\n"),
            uiFormat);
        umcRes = UMC_UNSUPPORTED;
    }

    vm_var32 uiFormatSet = uiFormat;
    if (UMC_OK == umcRes)
    {   umcRes = m_Device.Ioctl(SNDCTL_DSP_SETFMT, (vm_var32)&uiFormatSet); }

    if (UMC_OK == umcRes && uiFormat != uiFormatSet)
    {
        umcRes = UMC_UNSUPPORTED;
        vm_debug_trace(7,
            VM_STRING("OSSDev::SetBitsPerSample - unsupported: %dbps requested, %dbps returned\n"),
            uiFormat, uiFormatSet);
    }

    return umcRes;
}

UMC::Status
UMC::OSSDev::SetNumOfChannels(const vm_var32 uiNumOfChannels)
{
    Status umcRes = UMC_OK;
    vm_var32 uiNumOfChannelsSet = uiNumOfChannels;

    if (UMC_OK == umcRes)
    {
        umcRes = m_Device.Ioctl(SNDCTL_DSP_CHANNELS,
                                (vm_var32)&uiNumOfChannelsSet);
    }

    if (UMC_OK == umcRes && uiNumOfChannels != uiNumOfChannelsSet)
    {
        vm_debug_trace(7,
            VM_STRING("OSSDev::SetNumOfChannels - unsupported: %d channels requested, %d channels returned\n"),
            uiNumOfChannels, uiNumOfChannelsSet);
        umcRes = UMC_UNSUPPORTED;
    }

    return umcRes;
}

UMC::Status
UMC::OSSDev::SetFreq(const vm_var32 uiFreq)
{
    Status umcRes = UMC_OK;
    vm_var32 uiFreqSet = uiFreq;

    if (UMC_OK == umcRes)
    {   umcRes = m_Device.Ioctl(SNDCTL_DSP_SPEED, (vm_var32)&uiFreqSet);    }

    if (UMC_OK == umcRes && uiFreq != uiFreqSet)
    {
        vm_debug_trace(7,
            VM_STRING("OSSDev::SetFreq - unsupported: %dHz requested, %dHz returned\n"),
            uiFreq, uiFreqSet);
        umcRes = UMC_UNSUPPORTED;
    }

    return umcRes;
}

UMC::Status
UMC::OSSDev::Post()
{
    Status umcRes = m_Device.Ioctl(SNDCTL_DSP_POST);

    if (UMC_OK != umcRes)
    {   vm_debug_trace(7, VM_STRING("OSSDev::Post failed\n"));  }

    return umcRes;
}

UMC::Status
UMC::OSSDev::Reset()
{
    Status umcRes = m_Device.Ioctl(SNDCTL_DSP_RESET);

    if (UMC_OK == umcRes)
    {   umcRes = SetBitsPerSample(m_uiBitsPerSample);   }

    if (UMC_OK == umcRes)
    {   umcRes = SetNumOfChannels(m_uiNumOfChannels);   }

    if (UMC_OK == umcRes)
    {   umcRes = SetFreq(m_uiFreq);    }

    if (UMC_OK != umcRes)
    {   vm_debug_trace(7, VM_STRING("OSSDev::Reset failed\n"));  }

    m_uiBytesPlayed = 0;

    return umcRes;
}

UMC::Status
UMC::OSSDev::GetBytesPlayed(vm_var32& ruiBytesPlayed)
{
    Status umcRes = UMC_OK;

    count_info Info;
    Info.bytes = 0;
    umcRes = m_Device.Ioctl(SNDCTL_DSP_GETODELAY,(vm_var32)&Info);

    if (UMC_OK == umcRes)
    {   ruiBytesPlayed = m_uiBytesPlayed - Info.bytes;    }

    return umcRes;
}

#endif // UMC_ENABLE_OSS_AUDIO_RENDER