Question

I have a method that allows me to retrieve a 16 bit tiff image:
I am keeping only relevant information.

I use mainly:

        Stream imageStreamSource = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.Read);
        TiffBitmapDecoder decoder = new TiffBitmapDecoder(imageStreamSource, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
        
        BitmapSource bitmapSource = decoder.Frames[0];
        w = bitmapSource.PixelWidth; h = bitmapSource.PixelHeight;//width and height

        stride = w * bitmapSource.Format.BitsPerPixel / 8;//stride
        int byteSize = stride * h * bitmapSource.Format.BitsPerPixel / 16;//16 for a ushort array
        data = new ushort[byteSize];
        
        bitmapSource.CopyPixels(data, stride, 0); //Get pixels data into data array
        //bmpSource = bitmapSource;//used for reference
        originalFileData = new ushort[data.Length / 2];//used for reference (1 dimensional array representing the adus )
        Array.Copy(data, originalFileData, originalFileData.Length);
        bmp.WritePixels(new Int32Rect(0, 0, w, h), originalFileData, stride, 0);

I keep track of the array that I pass into the WritePixels method and call it "Filedata" to do a bit of image processing

I have a crop method:

crop(Rect rect) 
    {
    int newWidth=(int)Math.Floor(rect.TopRight.X-rect.TopLeft.X);
    int newHeight=(int)Math.Floor(rect.BottomRight.Y-rect.TopRight.Y);
    ushort[] newdata=new ushort[newWidth*newHeight];
    for (int i = (int)rect.TopLeft.X, i2 = 0; i2 < newWidth; i++, i2++)
        for (int j = (int)rect.TopLeft.Y, j2 = 0; j2 < newHeight; j++, j2++)
            newdata[j2 * newWidth + i2] = Filedata[j * Width + i];

and I try to make a new image out of the array newdata this way:

        WriteableBitmap bmp = new WriteableBitmap(newWidth, newHeight, dpi, dpi, PixelFormats.Gray16, null);
        bmp.WritePixels(new Int32Rect(0, 0, newWidth, newHeight), newdata,stride, 0);
        

but this last method gives me this exception:

"An unhandled exception of type ‘System.ArgumentException’ occurred in PresentationCore.dll

Additional information: Buffer size is not sufficient."

Now as far as I can see, I use the same method in the second part as in the first part, yet I can’t crop!

Any help would be most appreciated! thanks a lot!

Answer 1

I guess the stride value should match the actual width of the update rectangle:

stride = newWidth * (bmp.Format.BitsPerPixel + 7) / 8;
bmp.WritePixels(new Int32Rect(0, 0, newWidth, newHeight), newdata, stride, 0);