public override void DidOutputSampleBuffer(AVCaptureOutput captureOutput, CMSampleBuffer sampleBuffer, AVCaptureConnection connection)
{
var msSinceLastPreview = (DateTime.UtcNow - lastAnalysis).TotalMilliseconds;
if (msSinceLastPreview < scannerHost.ScanningOptions.DelayBetweenAnalyzingFrames ||
(wasScanned && msSinceLastPreview < scannerHost.ScanningOptions.DelayBetweenContinuousScans) ||
working ||
CancelTokenSource.IsCancellationRequested)
{
if (msSinceLastPreview < scannerHost.ScanningOptions.DelayBetweenAnalyzingFrames)
{
Console.WriteLine("Too soon between frames");
}
if (wasScanned && msSinceLastPreview < scannerHost.ScanningOptions.DelayBetweenContinuousScans)
{
Console.WriteLine("Too soon since last scan");
}
if (sampleBuffer != null)
{
sampleBuffer.Dispose();
sampleBuffer = null;
}
return;
}
wasScanned = false;
working = true;
lastAnalysis = DateTime.UtcNow;
try
{
// Get the CoreVideo image
using (var pixelBuffer = sampleBuffer.GetImageBuffer() as CVPixelBuffer)
{
// Lock the base address
pixelBuffer.Lock(CVPixelBufferLock.ReadOnly); // MAYBE NEEDS READ/WRITE
LuminanceSource luminanceSource;
// Let's access the raw underlying data and create a luminance source from it
unsafe
{
var rawData = (byte *)pixelBuffer.BaseAddress.ToPointer();
var rawDatalen = (int)(pixelBuffer.Height * pixelBuffer.Width * 4); //This drops 8 bytes from the original length to give us the expected length
luminanceSource = new CVPixelBufferBGRA32LuminanceSource(rawData, rawDatalen, (int)pixelBuffer.Width, (int)pixelBuffer.Height);
}
if (handleImage(luminanceSource))
{
wasScanned = true;
}
pixelBuffer.Unlock(CVPixelBufferLock.ReadOnly);
}
//
// Although this looks innocent "Oh, he is just optimizing this case away"
// this is incredibly important to call on this callback, because the AVFoundation
// has a fixed number of buffers and if it runs out of free buffers, it will stop
// delivering frames.
//
sampleBuffer.Dispose();
sampleBuffer = null;
}
catch (Exception e)
{
Console.WriteLine(e);
}
finally
{
working = false;
}
}
public override void DidOutputSampleBuffer(AVCaptureOutput captureOutput, CMSampleBuffer sampleBuffer, AVCaptureConnection connection)
{
var msSinceLastPreview = (DateTime.UtcNow - lastAnalysis).TotalMilliseconds;
if (msSinceLastPreview < scannerHost.ScanningOptions.DelayBetweenAnalyzingFrames ||
(wasScanned && msSinceLastPreview < scannerHost.ScanningOptions.DelayBetweenContinuousScans) ||
working ||
CancelTokenSource.IsCancellationRequested)
{
if (msSinceLastPreview < scannerHost.ScanningOptions.DelayBetweenAnalyzingFrames)
{
Console.WriteLine("Too soon between frames");
}
if (wasScanned && msSinceLastPreview < scannerHost.ScanningOptions.DelayBetweenContinuousScans)
{
Console.WriteLine("Too soon since last scan");
}
if (sampleBuffer != null)
{
sampleBuffer.Dispose();
sampleBuffer = null;
}
return;
}
wasScanned = false;
working = true;
lastAnalysis = DateTime.UtcNow;
try
{
// Get the CoreVideo image
using (var pixelBuffer = sampleBuffer.GetImageBuffer() as CVPixelBuffer)
{
// Lock the base address
pixelBuffer.Lock(CVPixelBufferLock.ReadOnly); // MAYBE NEEDS READ/WRITE
if (Picture)
{
Picture = false;
CapturedImage = null;
var baseAddress = pixelBuffer.BaseAddress;
nint bytesPerRow = pixelBuffer.BytesPerRow;
nint width = pixelBuffer.Width;
nint height = pixelBuffer.Height;
var flags = CGBitmapFlags.PremultipliedFirst | CGBitmapFlags.ByteOrder32Little;
// Create a CGImage on the RGB colorspace from the configured parameter above
using (var cs = CGColorSpace.CreateDeviceRGB())
using (var context = new CGBitmapContext(baseAddress, width, height, 8, bytesPerRow, cs, flags))
using (var cgImage = context.ToImage())
{
pixelBuffer.Unlock(CVPixelBufferLock.None);
CapturedImage = UIImage.FromImage(cgImage);
//SendPictureBack?.Invoke(this, CapturedImage);
HandleCapturedImage(CapturedImage);
}
}
LuminanceSource luminanceSource;
// Let's access the raw underlying data and create a luminance source from it
unsafe
{
var rawData = (byte *)pixelBuffer.BaseAddress.ToPointer();
var rawDatalen = (int)(pixelBuffer.Height * pixelBuffer.Width * 4); //This drops 8 bytes from the original length to give us the expected length
luminanceSource = new CVPixelBufferBGRA32LuminanceSource(rawData, rawDatalen, (int)pixelBuffer.Width, (int)pixelBuffer.Height);
}
if (HandleImage(luminanceSource))
{
wasScanned = true;
}
pixelBuffer.Unlock(CVPixelBufferLock.ReadOnly);
}
//
// Although this looks innocent "Oh, he is just optimizing this case away"
// this is incredibly important to call on this callback, because the AVFoundation
// has a fixed number of buffers and if it runs out of free buffers, it will stop
// delivering frames.
//
sampleBuffer.Dispose();
sampleBuffer = null;
}
catch (Exception e)
{
Console.WriteLine(e);
}
finally
{
working = false;
}
}
