Question

I m using WIA to acquire images from a scanner with C#. I can scan the papers, but I can t set up the page size correctly, it always defaults to A4 and I need to use Letter or Legal sometimes.

I tried with the WIA_DPS_PAGE_SIZE property, but when I try to set a value, I always get an error, that the value is out of the interval (tried a lot of possible values).

I wan t to be able to use WIA_DPS_PAGE_SIZE = WIA_PAGE_AUTO (for automatic page size), but I can t find anything on the web related to this.

Does anyone know a solution? thanks!

Answer 1

I know this is probably too late to actually help you with that, but it may become handy for future reference. To change scanned items properties use such code:

WIA.CommonDialog wiaDlg;
WIA.Device wiaDevice;
WIA.DeviceManager wiaManager = new DeviceManager();

wiaDlg = new WIA.CommonDialog();
wiaDevice = wiaDlg.ShowSelectDevice(WiaDeviceType.ScannerDeviceType, false, false);

foreach (WIA.Item item in wiaDevice.Items)
{
    StringBuilder propsbuilder = new StringBuilder();

    foreach (WIA.Property itemProperty in item.Properties)
    {
        IProperty tempProperty;
        Object tempNewProperty;

        if (itemProperty.Name.Equals("Horizontal Resolution"))
        {
            tempNewProperty = 75;
            ((IProperty)itemProperty).set_Value(ref tempNewProperty);
        }
        else if (itemProperty.Name.Equals("Vertical Resolution"))
        {
            tempNewProperty = 75;
            ((IProperty)itemProperty).set_Value(ref tempNewProperty);
        }
        else if (itemProperty.Name.Equals("Horizontal Extent"))
        {
            tempNewProperty = 619;
            ((IProperty)itemProperty).set_Value(ref tempNewProperty);
        }
        else if (itemProperty.Name.Equals("Vertical Extent"))
        {
            tempNewProperty = 876;
            ((IProperty)itemProperty).set_Value(ref tempNewProperty);
        }
    }

    image = (ImageFile)item.Transfer(WIA.FormatID.wiaFormatPNG);
}

This means that scanned document will be size A4 with dimensions 619 x 876.

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