Drawing a WaveForm from Line In

M

mikepayne

Member
Joined
Dec 22, 2005
Messages
6
Programming Experience
5-10
Hello everyone. This is quite a hard problem so any help AT ALL would be awesome.

I've got a program (below) which sets up 2 buffers and starts filling them with bytes from the microphone. I've got another thread running which analyses these bytes and plots a graph on a window. However, the graph that I draw isn't a straight line if there is no noise (as you might expect). It is all over the place. I know that the bytes are being correctly received since when I shout into the microphone, the graph clearly changes.

Also, if i make the buffers much larger than 128bytes, the program crashes. I know this is a tough one (or it is to me at least :) ), so if anyone can give me ANY pointers or info whatsoever, that would be great.

Thanks for your time guys.
Mike


VB.NET: 
[SIZE=2] 
[/SIZE][SIZE=2][COLOR=#0000ff]Imports[/COLOR][/SIZE][SIZE=2] System.Runtime.InteropServices
[/SIZE][SIZE=2][COLOR=#0000ff]Module[/COLOR][/SIZE][SIZE=2] modWave[/SIZE]
[SIZE=2] 
[/SIZE][SIZE=2][COLOR=#008000]'Constants...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Const[/COLOR][/SIZE][SIZE=2] WAVE_FORMAT_PCM [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2] = 1
[/SIZE][SIZE=2][COLOR=#0000ff]Const[/COLOR][/SIZE][SIZE=2] WAVE_MAPPER [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2] = -1
[/SIZE][SIZE=2][COLOR=#0000ff]Const[/COLOR][/SIZE][SIZE=2] CALLBACK_FUNCTION [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2] = &H30000
[/SIZE][SIZE=2][COLOR=#0000ff]Const[/COLOR][/SIZE][SIZE=2] CALLBACK_THREAD [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2] = 2097153
[/SIZE][SIZE=2][COLOR=#0000ff]Const[/COLOR][/SIZE][SIZE=2] MEM_COMMIT [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2] = 4096
[/SIZE][SIZE=2][COLOR=#0000ff]Const[/COLOR][/SIZE][SIZE=2] PAGE_READWRITE [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2] = 4
[/SIZE][SIZE=2][COLOR=#0000ff]Const[/COLOR][/SIZE][SIZE=2] WIM_OPEN [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2] = &H3BE
[/SIZE][SIZE=2][COLOR=#0000ff]Const[/COLOR][/SIZE][SIZE=2] WIM_CLOSE [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2] = &H3BF
[/SIZE][SIZE=2][COLOR=#0000ff]Public[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Const[/COLOR][/SIZE][SIZE=2] WIM_DATA [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2] = &H3C0
[/SIZE][SIZE=2][COLOR=#0000ff]Const[/COLOR][/SIZE][SIZE=2] BUFFER_SIZE [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2] = 128 [/SIZE][SIZE=2][COLOR=#008000]'CRASHES IF LARGER????
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Const[/COLOR][/SIZE][SIZE=2] NUMBER_OF_BUFFERS [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2] = 2[/SIZE]
[SIZE=2] 
[/SIZE][SIZE=2][COLOR=#008000]'API Declarations... 
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Declare[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Function[/COLOR][/SIZE][SIZE=2] waveInOpen [/SIZE][SIZE=2][COLOR=#0000ff]Lib[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"winmm.dll"[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Alias[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"waveInOpen"[/COLOR][/SIZE][SIZE=2] ([/SIZE][SIZE=2][COLOR=#0000ff]ByRef[/COLOR][/SIZE][SIZE=2] lphWaveIn [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] uDeviceID [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32, [/SIZE][SIZE=2][COLOR=#0000ff]ByRef[/COLOR][/SIZE][SIZE=2] lpFormat [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] WAVEFORMATEX, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] dwCallback [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] waveCallbackProc, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] dwInstance [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] UInt32, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] dwFlags [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32) [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Declare[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Function[/COLOR][/SIZE][SIZE=2] waveInStart [/SIZE][SIZE=2][COLOR=#0000ff]Lib[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"winmm.dll"[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Alias[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"waveInStart"[/COLOR][/SIZE][SIZE=2] ([/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] hWaveIn [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32) [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Declare[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Function[/COLOR][/SIZE][SIZE=2] waveInStop [/SIZE][SIZE=2][COLOR=#0000ff]Lib[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"winmm.dll"[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Alias[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"waveInStop"[/COLOR][/SIZE][SIZE=2] ([/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] hWaveIn [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32) [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Declare[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Function[/COLOR][/SIZE][SIZE=2] waveInAddBuffer [/SIZE][SIZE=2][COLOR=#0000ff]Lib[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"winmm.dll"[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Alias[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"waveInAddBuffer"[/COLOR][/SIZE][SIZE=2] ([/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] hWaveIn [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32, [/SIZE][SIZE=2][COLOR=#0000ff]ByRef[/COLOR][/SIZE][SIZE=2] lpWaveInHdr [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] WAVEHDR, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] uSize [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] UInt32) [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Declare[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Function[/COLOR][/SIZE][SIZE=2] waveInGetNumDevs [/SIZE][SIZE=2][COLOR=#0000ff]Lib[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"winmm.dll"[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Alias[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"waveInGetNumDevs"[/COLOR][/SIZE][SIZE=2] () [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Declare[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Function[/COLOR][/SIZE][SIZE=2] waveInGetDevCaps [/SIZE][SIZE=2][COLOR=#0000ff]Lib[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"winmm.dll"[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Alias[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"waveInGetDevCapsA"[/COLOR][/SIZE][SIZE=2] ([/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] uDeviceID [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2], [/SIZE][SIZE=2][COLOR=#0000ff]ByRef[/COLOR][/SIZE][SIZE=2] lpCaps [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] WAVEINCAPS, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] uSize [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2]) [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Declare[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Function[/COLOR][/SIZE][SIZE=2] waveInPrepareHeader [/SIZE][SIZE=2][COLOR=#0000ff]Lib[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"winmm.dll"[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Alias[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"waveInPrepareHeader"[/COLOR][/SIZE][SIZE=2] ([/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] hWaveIn [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32, [/SIZE][SIZE=2][COLOR=#0000ff]ByRef[/COLOR][/SIZE][SIZE=2] lpWaveInHdr [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] WAVEHDR, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] uSize [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] UInt32) [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Declare[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Function[/COLOR][/SIZE][SIZE=2] VirtualAlloc [/SIZE][SIZE=2][COLOR=#0000ff]Lib[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#800000]"kernel32"[/COLOR][/SIZE][SIZE=2] ([/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] lpAddress [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] dwSize [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] flAllocationType [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] flProtect [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32) [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#008000]'Alternative - with Thread - Declare Function waveInOpen Lib "winmm.dll" Alias "waveInOpen" (ByRef lphWaveIn As Int32, ByVal uDeviceID As Int32, ByRef lpFormat As WAVEFORMATEX, ByVal dwCallback As Int32, ByVal dwInstance As UInt32, ByVal dwFlags As Int32) As Int32[/COLOR][/SIZE]
[SIZE=2][COLOR=#008000] 
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'Define the signature of our callback procedure...[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff]Public[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Delegate[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Sub[/COLOR][/SIZE][SIZE=2] waveCallbackProc([/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] hwi [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] uMsg [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] UInt32, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] dwInstance [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32, [/SIZE][SIZE=2][COLOR=#0000ff]ByRef[/COLOR][/SIZE][SIZE=2] dwParam1 [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] WAVEHDR, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] dwparam2 [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32)[/SIZE]
[SIZE=2] 
[/SIZE][SIZE=2][COLOR=#008000]'API Structures...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Structure[/COLOR][/SIZE][SIZE=2] WAVEFORMATEX
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] wFormatTag [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int16
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] nChannels [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int16
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] nSamplesPerSec [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] nAvgBytesPerSec [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] nBlockAlign [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int16
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] wBitsPerSample [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int16
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] cbSize [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int16
[/SIZE][SIZE=2][COLOR=#0000ff]End[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Structure[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff] 
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Structure[/COLOR][/SIZE][SIZE=2] WAVEINCAPS
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] wMid [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int16
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] wPid [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int16
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] vDriverVersion [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int64
<MarshalAs(UnmanagedType.ByValArray, SizeConst:=32)> [/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] szpName() [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Char[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#008000]'String of length 32
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] dwFormats [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] wChannels [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int16
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] wReserved1 [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int16
[/SIZE][SIZE=2][COLOR=#0000ff]End[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Structure[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff] 
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Public[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Structure[/COLOR][/SIZE][SIZE=2] WAVEHDR
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] lpData [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] dwBufferLength [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] dwBytesRecorded [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] dwUser [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] dwFlags [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] dwLoops [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] reserved [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] lpNext [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32
[/SIZE][SIZE=2][COLOR=#0000ff]End[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Structure[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff] 
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'Create a number of WAVEHDRs for n-tuple buffering...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'One will be processed while another is being filled.
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] bufferHeader(NUMBER_OF_BUFFERS - 1) [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] WAVEHDR[/SIZE]
[SIZE=2] 
[/SIZE][SIZE=2][COLOR=#008000]'Define the callback procedure...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] pCallback [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] waveCallbackProc = [/SIZE][SIZE=2][COLOR=#0000ff]AddressOf[/COLOR][/SIZE][SIZE=2] waveInProc[/SIZE]
[SIZE=2] 
[/SIZE][SIZE=2][COLOR=#008000]'Store the handle to the waveIn device we are using...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] waveInHandle [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff] 
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'This array of bytes will store each chunk of input data...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] bytes(BUFFER_SIZE - 1) [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Byte[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff] 
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'This keeps track of the buffer number we are working with...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] bufferNumber [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Byte[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff] 
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'Create a thread that will draw a graph of the current buffer...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] waveFormDrawingThread [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]New[/COLOR][/SIZE][SIZE=2] Threading.Thread([/SIZE][SIZE=2][COLOR=#0000ff]AddressOf[/COLOR][/SIZE][SIZE=2] drawGraph)[/SIZE]
[SIZE=2] 
[/SIZE][SIZE=2][COLOR=#008000]'Declare a form to draw the new graph on...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] tfg [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]New[/COLOR][/SIZE][SIZE=2] Form[/SIZE]
[SIZE=2] 
[/SIZE][SIZE=2][COLOR=#008000]'This procedure opens the given wave device and starts waveIn on it...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Public[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Sub[/COLOR][/SIZE][SIZE=2] openWaveDevice([/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] devName [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2])
[/SIZE][SIZE=2][COLOR=#008000]'result of MM operations...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] result [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] UInt32
[/SIZE][SIZE=2][COLOR=#008000]'Create a wave format object and set it up for 16bit 44khz stereo...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] waveFormat [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] WAVEFORMATEX
waveFormat.wFormatTag = WAVE_FORMAT_PCM
waveFormat.nChannels = 2
waveFormat.nSamplesPerSec = 44100
waveFormat.wBitsPerSample = 16
waveFormat.nBlockAlign = waveFormat.nChannels * (waveFormat.wBitsPerSample / 8)
waveFormat.nAvgBytesPerSec = waveFormat.nSamplesPerSec * waveFormat.nBlockAlign
waveFormat.cbSize = 0
 

[/SIZE][SIZE=2][COLOR=#008000]'Try to open the preferred device...
[/COLOR][/SIZE][SIZE=2]result = waveInOpen(waveInHandle, WAVE_MAPPER, waveFormat, pCallback, 0, CALLBACK_FUNCTION)
[/SIZE][SIZE=2][COLOR=#0000ff]If[/COLOR][/SIZE][SIZE=2] (result) [/SIZE][SIZE=2][COLOR=#0000ff]Then[/COLOR][/SIZE][SIZE=2] MsgBox([/SIZE][SIZE=2][COLOR=#800000]"There was an error opening the device: "[/COLOR][/SIZE][SIZE=2] & result)[/SIZE]
[SIZE=2] 
[/SIZE][SIZE=2][COLOR=#008000]'Set up the first buffer.
[/COLOR][/SIZE][SIZE=2]bufferHeader(0).dwBufferLength = BUFFER_SIZE
bufferHeader(0).dwFlags = 0
 
[/SIZE][SIZE=2][COLOR=#008000]'Allocate the memory for all buffers at once...
[/COLOR][/SIZE][SIZE=2]bufferHeader(0).lpData = VirtualAlloc(0, bufferHeader(0).dwBufferLength * NUMBER_OF_BUFFERS, MEM_COMMIT, PAGE_READWRITE)
 
[/SIZE][SIZE=2][COLOR=#008000]'Prepare the first header...
[/COLOR][/SIZE][SIZE=2]result = waveInPrepareHeader(waveInHandle, bufferHeader(0), Marshal.SizeOf(bufferHeader(0)))
[/SIZE][SIZE=2][COLOR=#0000ff]If[/COLOR][/SIZE][SIZE=2] (result) [/SIZE][SIZE=2][COLOR=#0000ff]Then[/COLOR][/SIZE][SIZE=2] MsgBox([/SIZE][SIZE=2][COLOR=#800000]"Error preparing the first header. Error: "[/COLOR][/SIZE][SIZE=2] & result)[/SIZE]
[SIZE=2] 
[/SIZE][SIZE=2][COLOR=#008000]'Set up each additional buffer...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] b [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]For[/COLOR][/SIZE][SIZE=2] b = 1 [/SIZE][SIZE=2][COLOR=#0000ff]To[/COLOR][/SIZE][SIZE=2] NUMBER_OF_BUFFERS - 1[/SIZE]
[SIZE=2][COLOR=#008000]'Set up the bth buffer...
[/COLOR][/SIZE][SIZE=2]bufferHeader(b).dwBufferLength = BUFFER_SIZE
bufferHeader(b).dwFlags = 0
[/SIZE][SIZE=2][COLOR=#008000]'Point the bth buffer to the pre-allocated memory...
[/COLOR][/SIZE][SIZE=2]bufferHeader(b).lpData = bufferHeader(b - 1).lpData + bufferHeader(b - 1).dwBufferLength
[/SIZE][SIZE=2][COLOR=#008000]'Prepare the bth header...
[/COLOR][/SIZE][SIZE=2]result = waveInPrepareHeader(waveInHandle, bufferHeader(b), Marshal.SizeOf(bufferHeader(b)))
[/SIZE][SIZE=2][COLOR=#0000ff]If[/COLOR][/SIZE][SIZE=2] (result) [/SIZE][SIZE=2][COLOR=#0000ff]Then[/COLOR][/SIZE][SIZE=2] MsgBox([/SIZE][SIZE=2][COLOR=#800000]"There was an error preparing the "[/COLOR][/SIZE][SIZE=2] & b & [/SIZE][SIZE=2][COLOR=#800000]"th header. Error: "[/COLOR][/SIZE][SIZE=2] & result)
[/SIZE][SIZE=2][COLOR=#008000]'Try to add the bth buffer...
[/COLOR][/SIZE][SIZE=2]result = waveInAddBuffer(waveInHandle, bufferHeader(b), Marshal.SizeOf(bufferHeader(b)))
[/SIZE][SIZE=2][COLOR=#0000ff]If[/COLOR][/SIZE][SIZE=2] (result) [/SIZE][SIZE=2][COLOR=#0000ff]Then[/COLOR][/SIZE][SIZE=2] MsgBox([/SIZE][SIZE=2][COLOR=#800000]"There was an error adding the "[/COLOR][/SIZE][SIZE=2] & b & [/SIZE][SIZE=2][COLOR=#800000]"th buffer. Error: "[/COLOR][/SIZE][SIZE=2] & result)
[/SIZE][SIZE=2][COLOR=#0000ff]Next[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff] 
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'Try to start waveIn...
[/COLOR][/SIZE][SIZE=2]result = waveInStart(waveInHandle)
[/SIZE][SIZE=2][COLOR=#0000ff]If[/COLOR][/SIZE][SIZE=2] (result) [/SIZE][SIZE=2][COLOR=#0000ff]Then[/COLOR][/SIZE][SIZE=2] MsgBox([/SIZE][SIZE=2][COLOR=#800000]"There was an error starting wave input. Error: "[/COLOR][/SIZE][SIZE=2] & result)[/SIZE]
[SIZE=2] 
[/SIZE][SIZE=2][COLOR=#008000]'start the drawing thread...
[/COLOR][/SIZE][SIZE=2]waveFormDrawingThread.Start()
 
[/SIZE][SIZE=2][COLOR=#0000ff]End[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Sub[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff][/COLOR][/SIZE] 
[SIZE=2][COLOR=#0000ff] 
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'This procedure just stops waveIn...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Public[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Sub[/COLOR][/SIZE][SIZE=2] stopWave()
[/SIZE][SIZE=2][COLOR=#008000]'Try to stop the waveIn...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] result [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer[/COLOR][/SIZE][SIZE=2] = waveInStop(waveInHandle)
[/SIZE][SIZE=2][COLOR=#0000ff]If[/COLOR][/SIZE][SIZE=2] (result) [/SIZE][SIZE=2][COLOR=#0000ff]Then[/COLOR][/SIZE][SIZE=2] MsgBox([/SIZE][SIZE=2][COLOR=#800000]"There was an error stopping wav input "[/COLOR][/SIZE][SIZE=2] & result)
[/SIZE][SIZE=2][COLOR=#0000ff]End[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Sub
 
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'This method is run in a separate thread. It shows a window and 
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'continually draws the (continually updated) byte array on it. This might
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'be where the problem lies...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Public[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Sub[/COLOR][/SIZE][SIZE=2] drawGraph()
[/SIZE][SIZE=2][COLOR=#008000]'show the window...
[/COLOR][/SIZE][SIZE=2]tfg.Show()
[/SIZE][SIZE=2][COLOR=#008000]'Create a graphics object to draw on...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] g [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Graphics = tfg.CreateGraphics
[/SIZE][SIZE=2][COLOR=#008000]'a variable to store the y coordinate...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] y [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Long[/COLOR][/SIZE][SIZE=2] = 0
[/SIZE][SIZE=2][COLOR=#008000]'Infinite loop...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Do
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'clear the graphics object...
[/COLOR][/SIZE][SIZE=2]g.Clear(Color.Black)
[/SIZE][SIZE=2][COLOR=#008000]'Declare two points. One to draw from, one to draw to...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'Start drawing at X = 0, Y = middle of the window.
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] oldPoint [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]New[/COLOR][/SIZE][SIZE=2] Point(0, (g.VisibleClipBounds.Height / 2))
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] newPoint [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Point
[/SIZE][SIZE=2][COLOR=#008000]'For each byte...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] i [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]For[/COLOR][/SIZE][SIZE=2] i = 0 [/SIZE][SIZE=2][COLOR=#0000ff]To[/COLOR][/SIZE][SIZE=2] bytes.Length - 1
[/SIZE][SIZE=2][COLOR=#008000]'Set the Y coordinate...
[/COLOR][/SIZE][SIZE=2]y = (g.VisibleClipBounds.Height / 2) + bytes(i) - 127
[/SIZE][SIZE=2][COLOR=#008000]'create a new point to draw to...
[/COLOR][/SIZE][SIZE=2]newPoint = [/SIZE][SIZE=2][COLOR=#0000ff]New[/COLOR][/SIZE][SIZE=2] Point((g.VisibleClipBounds.Width / bytes.Length) * i, y)
[/SIZE][SIZE=2][COLOR=#008000]'Draw to that point...
[/COLOR][/SIZE][SIZE=2]g.DrawLine([/SIZE][SIZE=2][COLOR=#0000ff]New[/COLOR][/SIZE][SIZE=2] Pen(Color.Green, 1), oldPoint, newPoint)
[/SIZE][SIZE=2][COLOR=#008000]'set the old point to the new point...
[/COLOR][/SIZE][SIZE=2]oldPoint = newPoint
[/SIZE][SIZE=2][COLOR=#0000ff]Next
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'wait a while to avoid crashing....
[/COLOR][/SIZE][SIZE=2]waveFormDrawingThread.Sleep(200)
[/SIZE][SIZE=2][COLOR=#0000ff]Loop
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]End[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Sub[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff] 
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'Here's the callback. [/COLOR][/SIZE]
[SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Public[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Sub[/COLOR][/SIZE][SIZE=2] waveInProc([/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] hwi [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] uMsg [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] UInt32, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] dwInstance [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32, [/SIZE][SIZE=2][COLOR=#0000ff]ByRef[/COLOR][/SIZE][SIZE=2] dwParam1 [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] WAVEHDR, [/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] dwparam2 [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] Int32)
[/SIZE][SIZE=2][COLOR=#008000]'If we've received data...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]If[/COLOR][/SIZE][SIZE=2] uMsg = WIM_DATA [/SIZE][SIZE=2][COLOR=#0000ff]Then
[/COLOR][/SIZE][SIZE=2][COLOR=#008000]'Copy the current buffer into the bytes array...
[/COLOR][/SIZE][SIZE=2]Marshal.Copy(dwParam1.lpData, bytes, 0, BUFFER_SIZE)
[/SIZE][SIZE=2][COLOR=#008000]'Try to requeue the buffer...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] result [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Integer
[/COLOR][/SIZE][SIZE=2]result = waveInAddBuffer(waveInHandle, bufferHeader(bufferNumber), Marshal.SizeOf(bufferHeader(bufferNumber)))
[/SIZE][SIZE=2][COLOR=#0000ff]If[/COLOR][/SIZE][SIZE=2] (result) [/SIZE][SIZE=2][COLOR=#0000ff]Then[/COLOR][/SIZE][SIZE=2] MsgBox([/SIZE][SIZE=2][COLOR=#800000]"There was an error requeuing buffer "[/COLOR][/SIZE][SIZE=2] & bufferNumber & [/SIZE][SIZE=2][COLOR=#800000]" :"[/COLOR][/SIZE][SIZE=2] & result)
[/SIZE][SIZE=2][COLOR=#008000]'Move to the next buffer...
[/COLOR][/SIZE][SIZE=2]bufferNumber += 1
bufferNumber = bufferNumber [/SIZE][SIZE=2][COLOR=#0000ff]Mod[/COLOR][/SIZE][SIZE=2] NUMBER_OF_BUFFERS
[/SIZE][SIZE=2][COLOR=#0000ff]End[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]If
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]If[/COLOR][/SIZE][SIZE=2] uMsg = WIM_OPEN [/SIZE][SIZE=2][COLOR=#0000ff]Then
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'TODO
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]End[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]If
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]If[/COLOR][/SIZE][SIZE=2] uMsg = WIM_CLOSE [/SIZE][SIZE=2][COLOR=#0000ff]Then
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'TODO
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]End[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]If
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]End[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Sub
[/COLOR][/SIZE][SIZE=2]
 
 
[/SIZE][SIZE=2][COLOR=#008000]'Lists wave devices. Not relevant here...
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Public[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Sub[/COLOR][/SIZE][SIZE=2] listWaveDevices()
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] wic [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] WAVEINCAPS
[/SIZE][SIZE=2][COLOR=#0000ff]ReDim[/COLOR][/SIZE][SIZE=2] wic.szpName(32)
[/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] iNumDevs [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]ULong
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] i [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]ULong
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#008000]'/* Get the number of Digital Audio In devices in this computer */
[/COLOR][/SIZE][SIZE=2]iNumDevs = waveInGetNumDevs()
[/SIZE][SIZE=2][COLOR=#0000ff]For[/COLOR][/SIZE][SIZE=2] i = 0 [/SIZE][SIZE=2][COLOR=#0000ff]To[/COLOR][/SIZE][SIZE=2] iNumDevs
[/SIZE][SIZE=2][COLOR=#0000ff]If[/COLOR][/SIZE][SIZE=2] (waveInGetDevCaps(i, wic, Marshal.SizeOf(wic)) = 0) [/SIZE][SIZE=2][COLOR=#0000ff]Then
[/COLOR][/SIZE][SIZE=2]MsgBox(wic.szpName)
[/SIZE][SIZE=2][COLOR=#0000ff]End[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]If
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]Next
[/COLOR][/SIZE][SIZE=2][/SIZE][SIZE=2][COLOR=#0000ff]End[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Sub
 
End[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]Module
[/COLOR][/SIZE]
 
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You say that the program crashes but you give no indication of which line it crashes on or what the error message is. Do you really expect us to just read all that relatively complex code and just hope that something jumps out? Give us something to work with.
 
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Waveforms

Woah, sorry man. I actually plain forgot, I do apologise. The program crashes if I up the size of the buffer. But the error messages given vary. But that's not really the problem. What I don't understand and was hoping someone might be able to help me with was the fact that the bytes when coming in from the audio line are all over the place. When i expect the waveform to be flat (because there is no noise), it is all over the place. Obviously there will be some noise because it is an analog device, but surely not this much. So am i doing something wrong?

Also, I know i'm getting the right bytes, because when I shout into the mic, the graph changes.

And I'm sorry again if I annoyed you in any way, my bad.

Thanks for your time
Mike
 
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There seem to be several errors with your code, both with the use of the waveIn-- functions and with threading/memory handle.
(you don't free memory, you don't abort the draw thread on stop/exit..)

First have a look at the functions listed at AllApi, there is an example 'Audio input/output level' (in VB6) that shows some of the flow:
http://www.mentalis.org/apilist/w.shtml
I could tell that in your waveInProc you are not accessing the correct buffer as it is received (from my perception), you'll see this clearly in mentioned example. Here you also keep requeueing after error/stop, which seemed to cause the strange 33 return value. (they also do reset and waveInUnprepareHeader)

Do also search Google or some for other examples on the web, lots of people have done this before (esp.VB6), if you're lucky there is even one fully translated to VB.Net.

About the "all over the place" stuff:
I read values between 0-255 for sound/silence from the bytes. Almost silence is something near 0 AND/OR 255, the sound wave if perhaps circular in this context. I found that setting a hi+low filter (called treshold?) of 30 removed all what looked like noise when I thought there was silence. This means I only processed the graph when value was above (0+30) and below (255-30), for the time the project ran ;) this made successful graphing, I think.
 
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Thanks

Thanks a lot for your help, I'm sure this example will help me out.

It's funny, I really couldn't find examples of this on google, ah well.

Just for information purposes, the problem with all the data being all over the place was stupidity on my part. I had input set to 16bits, so of course the samples were 2 bytes, in the range -32768 to 32767, and i was processing them as bytes. So each byte in my byte array was actually half of a 16 bit signed integer. What a fool :D

Anyway. I found it easiest to just change to 8 bit input. If i need any more help, i'll definitely post here. THanks for the helpful reply.
Mike
 
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