EasyPlayerPro windows播放器本地音频播放音量控制实现

背景描述

作为一个播放器, 除了能播放视频和声音外，音量控制是绝对不能缺少的功能; 本文在音视频播放的基础上，增加对音量的控制；

实现流程

• 调用mixerGetDevCaps获取音频输出设备列表;
• 打开指定的音频输出设备;
• 获取指定音频输出设备的音频属性;
• 获取和设置音量;

    DWORD GetVolume();    int   SetVolume(DWORD vol);    int   Init(DWORD ComponentType,int *min,int *max);    int     GetAudioOutputDeviceList(MIXER_DEVICE_INFO_T    **devicelist, int *deviceNum);    int     SetAudioDeviceId(int _deviceIdx);

代码实现

//获取音频输出设备列表int CVolumeControl::GetAudioOutputDeviceList(MIXER_DEVICE_INFO_T    **devicelist, int *deviceNum){int     idx = 0;if (mDeviceNum < 1){    MIXERCAPS           mxcaps;    UINT cMixerDevs = mixerGetNumDevs();    for (UINT iDevIndex = 0; iDevIndex < cMixerDevs && iDevIndex<MAX_MIXER_DEVICE_NUM; iDevIndex++)    {        mixerGetDevCaps(iDevIndex, &mxcaps, sizeof(mxcaps));        mixerDeviceList[iDevIndex].id = iDevIndex;        strcpy(mixerDeviceList[iDevIndex].name, mxcaps.szPname);    }    mDeviceNum = cMixerDevs;}if (NULL != deviceNum)      *deviceNum = mDeviceNum;if (NULL != devicelist)     *devicelist = &mixerDeviceList[0];return 0;}//获取音量DWORD CVolumeControl::GetVolume(){int devIdx = mDeviceId;if (devIdx < 0)     return -1;HMIXER hMixer;MMRESULT        mmhr;mmhr = mixerOpen(&hMixer, devIdx, 0, 0, MIXER_OBJECTF_HMIXER|MIXER_GETLINEINFOF_DESTINATION);if( mmhr != MMSYSERR_NOERROR ){    _TRACE(TRACE_LOG_ERROR, "GetVolume::mixerOpen fail. %d\n", mmhr);    return 0;}MIXERCAPS   tmixercaps;if( mixerGetDevCaps( devIdx, &tmixercaps, sizeof(MIXERCAPS)) != MMSYSERR_NOERROR ) {    mixerClose(hMixer);    return -1;}bool ffind = false;MIXERLINE       mxline;for(int i = 0; i < (int)tmixercaps.cDestinations; i++ ) {    ZeroMemory( &mxline, sizeof(MIXERLINE) );    mxline.cbStruct      = sizeof(MIXERLINE);    mxline.dwDestination = i;    mmhr = ::mixerGetLineInfo( (HMIXEROBJ)hMixer, &mxline, MIXER_OBJECTF_HMIXER);// | MIXER_GETLINEINFOF_COMPONENTTYPE );    if( mmhr != MMSYSERR_NOERROR ) {        continue;    }    else {        if( mxline.dwComponentType == MIXERLINE_COMPONENTTYPE_DST_DIGITAL )         {            if( 0 != (MIXERLINE_LINEF_ACTIVE & mxline.fdwLine) )             {                ffind = true;                break;            }        }        else if( mxline.dwComponentType == MIXERLINE_COMPONENTTYPE_DST_MONITOR )         {            if( 0 != (MIXERLINE_LINEF_ACTIVE & mxline.fdwLine) )             {                ffind = true;                break;            }        }        else if( mxline.dwComponentType == MIXERLINE_COMPONENTTYPE_DST_SPEAKERS )         {            if( 0 != (MIXERLINE_LINEF_ACTIVE & mxline.fdwLine) )             {                ffind = true;                break;            }        }    }}MIXERCONTROL    mxcWaveoutMux;memset(&mxcWaveoutMux, 0x00, sizeof(MIXERCONTROL));    _GetLineControls( hMixer, mxline, &mxcWaveoutMux, NULL, NULL );MIXERCONTROLDETAILS mxcd;MIXERCONTROLDETAILS_UNSIGNED mxdu;memset(&mxdu, 0x00, sizeof(MIXERCONTROLDETAILS_UNSIGNED));mxcd.cbStruct = sizeof(MIXERCONTROLDETAILS);mxcd.cMultipleItems = 0;  mxcd.cChannels = mxline.cChannels;mxcd.dwControlID = mxcWaveoutMux.dwControlID;mxcd.cbDetails = sizeof(MIXERCONTROLDETAILS_UNSIGNED);mxcd.paDetails = &mxdu;mmhr = mixerGetControlDetails((HMIXEROBJ)hMixer, &mxcd, MIXER_OBJECTF_HMIXER | MIXER_GETCONTROLDETAILSF_VALUE);if( mmhr != MMSYSERR_NOERROR ){    _TRACE(TRACE_LOG_ERROR, "GetVolume::mixerGetControlDetails fail. %d\n", mmhr);}mixerClose(hMixer);_TRACE(TRACE_LOG_DEBUG, "GetVolume: %d\n", mxdu.dwValue);return mxdu.dwValue;}//设置音量int CVolumeControl::SetVolume(DWORD vol){int devIdx = mDeviceId;if (devIdx < 0)     return -1;HMIXER hMixer;MMRESULT        mmhr;mmhr = mixerOpen(&hMixer, 0, 0, 0, 0);if (mmhr!= MMSYSERR_NOERROR){    _TRACE(TRACE_LOG_ERROR, "mixerOpen fail. %d\n", mmhr);    return -1;}MIXERCAPS   tmixercaps;if( mixerGetDevCaps( devIdx, &tmixercaps, sizeof(MIXERCAPS)) != MMSYSERR_NOERROR ) {    mixerClose(hMixer);    return -1;}bool ffind = false;MIXERLINE       mxline;for(int i = 0; i < (int)tmixercaps.cDestinations; i++ ) {    ZeroMemory( &mxline, sizeof(MIXERLINE) );    mxline.cbStruct      = sizeof(MIXERLINE);    mxline.dwDestination = i;    mmhr = ::mixerGetLineInfo( (HMIXEROBJ)hMixer, &mxline, MIXER_OBJECTF_HMIXER);// | MIXER_GETLINEINFOF_COMPONENTTYPE );    if( mmhr != MMSYSERR_NOERROR ) {        continue;    }    else {        //        if( mxline.dwComponentType == MIXERLINE_COMPONENTTYPE_DST_DIGITAL )         {            if( 0 != (MIXERLINE_LINEF_ACTIVE & mxline.fdwLine) )             {                ffind = true;                break;            }        }        else if( mxline.dwComponentType == MIXERLINE_COMPONENTTYPE_DST_MONITOR )         {            if( 0 != (MIXERLINE_LINEF_ACTIVE & mxline.fdwLine) )             {                ffind = true;                break;            }        }        else if( mxline.dwComponentType == MIXERLINE_COMPONENTTYPE_DST_SPEAKERS )         {            if( 0 != (MIXERLINE_LINEF_ACTIVE & mxline.fdwLine) )             {                ffind = true;                break;            }        }    }}MIXERCONTROL    mxcWaveoutMux;memset(&mxcWaveoutMux, 0x00, sizeof(MIXERCONTROL));    _GetLineControls( hMixer, mxline, &mxcWaveoutMux, NULL, NULL );int ret = 0;MIXERCONTROLDETAILS mxcd;MIXERCONTROLDETAILS_UNSIGNED mxdu;memset(&mxdu, 0x00, sizeof(MIXERCONTROLDETAILS_UNSIGNED));mxdu.dwValue = vol;mxcd.cMultipleItems = 0; mxcd.cChannels = mxline.cChannels;mxcd.cbStruct = sizeof(MIXERCONTROLDETAILS);mxcd.dwControlID = mxcWaveoutMux.dwControlID;mxcd.cbDetails = sizeof(MIXERCONTROLDETAILS_UNSIGNED);mxcd.paDetails = &mxdu;mmhr = mixerSetControlDetails((HMIXEROBJ)hMixer, &mxcd, MIXER_SETCONTROLDETAILSF_VALUE | MIXER_OBJECTF_HMIXER); if (mmhr != MMSYSERR_NOERROR){    ret = -1;}mixerClose(hMixer);return ret;}

关于EasyPlayerPro播放器

EasyPlayerPro是一款全功能的流媒体播放器，支持RTSP、RTMP、HTTP、HLS、UDP、RTP、File等多种流媒体协议播放、支持本地文件播放，支持本地抓拍、本地录像、播放旋转、多屏播放、倍数播放等多种功能特性，核心基于ffmpeg，稳定、高效、可靠、可控，支持Windows、Android、iOS三个平台，目前在多家教育、安防、行业型公司，都得到的应用，广受好评！

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