public static SoundFormat[] GetFormats(string deviceId, bool queryEncoderFormats)
{
// Get device by id
if (string.IsNullOrEmpty(deviceId))
{
throw new ArgumentNullException("deviceId");
}
if (!queryEncoderFormats)
{
return(sharedWrapper.GetDeviceFormats(deviceId));
}
// Get device formats
SoundFormat[] deviceFormats = sharedWrapper.GetDeviceFormats(deviceId);
// Get list of input formats that has not been quieried yet
List <SoundFormat> newInputFormats = new List <SoundFormat>();
foreach (SoundFormat deviceFormat in deviceFormats)
{
// Any convertion exists?
if (!convertionMap.Contains(deviceFormat) && deviceFormat.Tag == preferredFormat.Tag)
{
newInputFormats.Add(deviceFormat);
}
}
// Is there any new format to query
if (newInputFormats.Count > 0)
{
var encoderConvertionMap = AcmEncoder.GetConvertionMap(newInputFormats.ToArray(), preferredFormat.Tag);
// Add new map to the current map
convertionMap.Add(encoderConvertionMap);
// Add no convertion -input format as output format- to the map
foreach (SoundFormat newInputFormat in newInputFormats)
{
convertionMap.Add(newInputFormat, newInputFormat);
}
}
// Get all of the output formats matching device formats as input
return(convertionMap.GetOutputs(deviceFormats));
}
private SoundFormat GetInputFormat(out bool encoderNeeded)
{
int nMaxAvgBytesPerSec = 0;
// Get device formats
SoundFormat[] deviceFormats = this.wrapper.GetDeviceFormats(deviceId);
List <SoundFormat> deviceFormatList = new List <SoundFormat>(deviceFormats);
SoundFormat inputFormat = null;
if (this.format == null)
{
// If format is not specified, find the format with maximum average bytes per second
foreach (SoundFormat deviceFormat in deviceFormatList)
{
if (inputFormat == null || nMaxAvgBytesPerSec < deviceFormat.AverageBytesPerSecond)
{
inputFormat = deviceFormat;
nMaxAvgBytesPerSec = deviceFormat.AverageBytesPerSecond;
}
}
if (inputFormat == null)
{
// This happens only if device has not formats
throw new InvalidOperationException("Cannot find an appropriate input format.");
}
encoderNeeded = false;
return(inputFormat);
}
// Check if device supports the format
if (deviceFormatList.Contains(this.format))
{
encoderNeeded = false;
return(this.format);
}
// Get available input formats for convertion
SoundFormat[] availableInputs = convertionMap.GetInputs(this.format);
if (availableInputs.Length == 0)
{
// Get convertion map again
// We currenty use PCM format for output.
convertionMap.Add(AcmEncoder.GetConvertionMap(deviceFormatList.ToArray(), preferredFormat.Tag));
// Get available input formats for convertion
availableInputs = convertionMap.GetInputs(this.format);
if (availableInputs.Length == 0)
{
throw new InvalidOperationException("Cannot find an appropriate input format.");
}
}
// Find the input format that device supports and has
// maximum average bytes per second
foreach (SoundFormat input in availableInputs)
{
if (deviceFormatList.Contains(input))
{
if (nMaxAvgBytesPerSec < input.AverageBytesPerSecond &&
(inputFormat == null ||
input.AverageBytesPerSecond == (input.BitsPerSample / 8) * input.Channels * input.SamplesPerSecond))
{
inputFormat = input;
nMaxAvgBytesPerSec = (int)input.AverageBytesPerSecond;
}
}
}
if (inputFormat == null)
{
throw new InvalidOperationException("Cannot find an appropriate input format.");
}
encoderNeeded = true;
return(inputFormat);
}