I am trying to create an image from a byte array. The byte array is created by a fingerprint scanner (cf CaptureFrame method). fwidth is 256 and fheight is 255.
When I run the code below, I get
System.ArgumentException: Parameter is not valid.
Dim fWidth As Short
Dim fHeight As Short
DFRProxy.DFRProxy.GetImageDimensions(fWidth, fHeight)
Dim imgBufLength As Integer = CInt(fWidth) * fHeight
Dim finger(imgBufLength) As Byte
Dim startCap As Short = DFRProxy.DFRProxy.StartCapture(0)
Dim capFrame As Short = DFRProxy.DFRProxy.CaptureFrame(0, finger, 0)
Using ms As New IO.MemoryStream(finger)
thisImage = Image.FromStream(ms)
End Using
The error occurs at line
thisImage = Image.FromStream(ms)
The byte array has 65280 elements. I have reviewed several StackOverflow postings that are similar to this, but nothing has worked. I have tried setting the useEmbeddedColorManagement
and validateImageData
parameters for the FromStream method to False and True, but this does not solve the problem.
Do you have any suggestions on how to correct the ArgumentException
?
FromStream is expecting data in one of these formats:
Managed GDI+ has built-in encoders and decoders that support the following file types:
- BMP
- GIF
- JPEG
- PNG
- TIFF
Your byte array I suspect is not in these and does not have the metadata or compression information each of these formats expects.
What you want to do is create a Bitmap object and read through each pixel in the byte array, calling SetPixel in the bitmap for the appropriate pixel. You'll end up with a Bitmap (which is an Image) that has the pixels you want.