Use WindowsAPI to get audio recordings

Non-reproduced

Introduction to the acquisition of audio streams using winmm.h

You first need to include the following reference objects

#include <Windows.h>
#include "mmsystem.h"
#pragma comment (lib, "Winmm.lib")

Audio acquisition requires 7 functions to be called

1. Waveingetnumdevs: Returns the number of waveform sound input devices ready in the system

UINT Waveingetnumdevs (VOID);

2. Waveingetdevcaps: Check the characteristics of the specified waveform input device

mmresult waveingetdevcaps (uint_ptr Udeviceid, Lpwaveincaps Pwic, UINT Cbwic);//Udeviceid the audio input device identity, or a handle to an open audio input device.//personally, if you have more than one device in the previous step, you can identify each device with an index.//    //Pwic A pointer to the WAVEINCAPS structure that contains the audio characteristics of the device.////Cbwic the size of the WAVEINCAPS structure, use sizeof.////results of mmresult function execution//Mmsyserr_noerror indicates successful execution//Mmsyserr_baddeviceid index out of bounds//Mmsyserr_nodriver not ready for the device//Mmsyserr_nomem cannot allocate or lock memory

Introduction to the meaning of Waveincaps structural body

 typedef struct   {WORD wmid;                 //  audio device manufacturer-defined driver identification  WORD wpid; //            Mmversion vdriverversion; //     driver version number  TCHAR Szpname[maxpnamelen]; //     manufacturer name             DWORD Dwformats; //     supported formats, see MSDN             WORD Wchannels; //     number of channels supported             WORD wReserved1; //  reserved parameter } Waveincaps; 

3. Waveinopen: Open the specified audio input device for recording

mmresult waveinopen (  lphwavein       phwi,                // pointer  to Hwavein structure that receives an open audio input device identity Uint_ptr       Udeviceid,            // Specify a device ID that needs to be opened. You can use Wave_mapper to select a device  to record in a specified recording format Lpwaveformatex pwfx,                //  dword_ptr      dwcallback,/        /  Points to a callback function, an event handle, a window handle, a thread identity, and processes the recording event.  Dword_ptr      // pass to callback mechanism parameter  DWORD          fdwopen            // Open device method ID, Specifies the type of callback. See Csdn);

Introduction to the meaning of WaveFormatEx structural body

typedefstruct{WORD wFormatTag; //waveform sound format, mono dual channel using WAVE_FORMAT_PCM. When included in the waveformatextensible structure, use the wave_format_extensible.WORD nchannels;//Number of channelsDWORD nsamplespersec;//sample rate. When wFormatTag is WAVE_FORMAT_PCM, there are 8.0khz,11.025khz,22.05khz, and 44.1kHz.DWORD navgbytespersec;//the number of sampled bytes per second. Calculated by Nsamplespersec * Nchannels * WBITSPERSAMPLE/8WORD nblockalign;//the number of bytes per sample. Calculated by Nchannels * WBITSPERSAMPLE/8WORD wBitsPerSample;//The number of sample bits. When wFormatTag is WAVE_FORMAT_PCM, it is 8 orWORD cbsize;//when wFormatTag is WAVE_FORMAT_PCM, this parameter is ignored} WaveFormatEx;

Introducing the Dwcallback callback function format

void CALLBACK Waveinproc (  hwavein hwi,          / / callback device handle for this function  UINT umsg,            // waveform Sound input information, identification off (wim_close), buffer Full (wim_data), open (Wim_open).  // data specified by the user in Waveinopen   dword_ptr dwParam1,   //(LPWAVEHDR) dwParam1, user-specified buffer  dword_ptr dwParam2     );

4. Waveinprepareheader: Prepare a buffer for the audio input device

mmresult waveinprepareheader (  hwavein hwi,    / / audio input device handle  lpwavehdr PWH,//  A pointer to the WAVEHDR structure that identifies the size of the prepared buffer  UINT CBWH        //WAVEHDR structure, using sizeof );

Introducing the WAVEHDR structure

typedefstructWavehdr_tag {LPSTR lpdata; //a buffer that points to the waveform formatDWORD dwbufferlength;//size of the bufferDWORD dwbytesrecorded;//How much data is currently storedDword_ptr Dwuser;//User DataDWORD DwFlags;//The information provided for the buffer, used in the Waveinprepareheader function whdr_preparedDWORD Dwloops;//use when output, identify the number of plays    structWavehdr_tag * LPNEXT;//reservedDWORD_PTR reserved;//reserved} WAVEHDR, *lpwavehdr;

5. Waveinaddbuffer: Sends the buffer to the device and does not work if the buffer fills up. (parameter same as above)

Mmresult Waveinaddbuffer (  hwavein hwi,   lpwavehdr PWH,   

6. Waveinstart: Start recording

mmresult Waveinstart (  hwavein hwi  //device handle);

7. Waveinclose: Turn off the device

mresult waveinclose (  hwavein hwi  //device handle);

The following example:

http://download.csdn.net/detail/long7782/7771019