/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// METHODS //////////////////////////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
private string GenerateFriendlyName(ImageScannerFormat targetFormat)
{
switch (targetFormat)
{
case ImageScannerFormat.Jpeg:
return("JPG");
case ImageScannerFormat.Png:
return("PNG");
case ImageScannerFormat.DeviceIndependentBitmap:
return("BMP");
case ImageScannerFormat.Tiff:
return("TIF");
case ImageScannerFormat.Xps:
return("XPS");
case ImageScannerFormat.OpenXps:
return("OpenXPS");
case ImageScannerFormat.Pdf:
return("PDF");
default:
throw new ArgumentException("Unable to generate FriendlyName from format " + targetFormat + ".");
}
}
/// <summary>
/// Converts a <see cref="ImageScannerFormat"/> into the corresponding format string.
/// </summary>
/// <param name="format">An image format.</param>
/// <returns>The corresponding string.</returns>
public static string ConvertImageScannerFormatToString(ImageScannerFormat format)
{
switch (format)
{
case ImageScannerFormat.Jpeg:
return(".jpg");
case ImageScannerFormat.Png:
return(".png");
case ImageScannerFormat.DeviceIndependentBitmap:
return(".bmp");
case ImageScannerFormat.Tiff:
return(".tif");
case ImageScannerFormat.Xps:
return(".xps");
case ImageScannerFormat.OpenXps:
return(".oxps");
case ImageScannerFormat.Pdf:
return(".pdf");
default:
throw new ApplicationException("ConvertImageScannerFormatToImageScannerFormat received invalid ImageScannerFormat '" + format + "' for conversion.");
}
}
/// <summary>
/// Converts the given <see cref="ImageScannerFormat"/> into a glyph string.
/// </summary>
public object Convert(object value, Type targetType, object parameter, string language)
{
ImageScannerFormat format = (ImageScannerFormat)value;
switch (format)
{
case ImageScannerFormat.Jpeg:
return(glyphImage);
case ImageScannerFormat.Png:
return(glyphImage);
case ImageScannerFormat.DeviceIndependentBitmap:
return(glyphImage);
case ImageScannerFormat.Tiff:
return(glyphImage);
case ImageScannerFormat.Xps:
return(glyphImage);
case ImageScannerFormat.OpenXps:
return(glyphImage);
case ImageScannerFormat.Pdf:
return(glyphPdf);
default:
break;
}
return((int)value);
}
/// <summary>
/// Checks whether the given format is an image format.
/// </summary>
public static bool IsImageFormat(ImageScannerFormat format)
{
switch (format)
{
case ImageScannerFormat.Jpeg:
case ImageScannerFormat.Png:
case ImageScannerFormat.DeviceIndependentBitmap:
case ImageScannerFormat.Tiff:
return(true);
case ImageScannerFormat.Xps:
case ImageScannerFormat.OpenXps:
case ImageScannerFormat.Pdf:
default:
return(false);
}
}
public bool SupportsFileFormat(ScannerSource source, ImageScannerFormat format)
{
switch (source)
{
case ScannerSource.Auto:
return(AutoFormats.Any((x) => x.TargetFormat == format));
case ScannerSource.Flatbed:
return(FlatbedFormats.Any((x) => x.TargetFormat == format));
case ScannerSource.Feeder:
return(FeederFormats.Any((x) => x.TargetFormat == format));
case ScannerSource.None:
default:
return(false);
}
}
/// <summary>
/// Attempts to determine the <see cref="BitmapRotation"/> needed to fix the orientation of the given
/// <paramref name="imageFile"/>.
/// </summary>
public async Task <BitmapRotation> TryGetRecommendedRotationAsync(StorageFile imageFile, ImageScannerFormat format)
{
try
{
if (OcrEngine != null)
{
// get separate stream
using (IRandomAccessStream sourceStream = await imageFile.OpenAsync(FileAccessMode.Read))
{
BitmapDecoder decoder = await BitmapDecoder.CreateAsync(sourceStream);
Tuple <BitmapRotation, int> bestRotation;
// create rotated 0°
SoftwareBitmap bitmap = await decoder.GetSoftwareBitmapAsync();
OcrResult ocrResult = await OcrEngine.RecognizeAsync(bitmap);
bestRotation = new Tuple <BitmapRotation, int>(BitmapRotation.None, ocrResult.Text.Length);
using (InMemoryRandomAccessStream targetStream = new InMemoryRandomAccessStream())
{
// create rotated 90°
BitmapEncoder encoder = await HelperService.CreateOptimizedBitmapEncoderAsync(format, targetStream);
encoder.SetSoftwareBitmap(bitmap);
encoder.BitmapTransform.Rotation = BitmapRotation.Clockwise90Degrees;
await encoder.FlushAsync();
decoder = await BitmapDecoder.CreateAsync(targetStream);
bitmap = await decoder.GetSoftwareBitmapAsync();
ocrResult = await OcrEngine.RecognizeAsync(bitmap);
if (ocrResult.Text.Length > bestRotation.Item2)
{
bestRotation = new Tuple <BitmapRotation, int>(BitmapRotation.Clockwise90Degrees, ocrResult.Text.Length);
}
}
using (InMemoryRandomAccessStream targetStream = new InMemoryRandomAccessStream())
{
// create rotated 180°
BitmapEncoder encoder = await HelperService.CreateOptimizedBitmapEncoderAsync(format, targetStream);
encoder.SetSoftwareBitmap(bitmap);
encoder.BitmapTransform.Rotation = BitmapRotation.Clockwise90Degrees;
await encoder.FlushAsync();
decoder = await BitmapDecoder.CreateAsync(targetStream);
bitmap = await decoder.GetSoftwareBitmapAsync();
ocrResult = await OcrEngine.RecognizeAsync(bitmap);
if (ocrResult.Text.Length > bestRotation.Item2)
{
bestRotation = new Tuple <BitmapRotation, int>(BitmapRotation.Clockwise180Degrees, ocrResult.Text.Length);
}
}
using (InMemoryRandomAccessStream targetStream = new InMemoryRandomAccessStream())
{
// create rotated 270°
BitmapEncoder encoder = await HelperService.CreateOptimizedBitmapEncoderAsync(format, targetStream);
encoder.SetSoftwareBitmap(bitmap);
encoder.BitmapTransform.Rotation = BitmapRotation.Clockwise90Degrees;
await encoder.FlushAsync();
decoder = await BitmapDecoder.CreateAsync(targetStream);
bitmap = await decoder.GetSoftwareBitmapAsync();
ocrResult = await OcrEngine.RecognizeAsync(bitmap);
if (ocrResult.Text.Length > bestRotation.Item2)
{
bestRotation = new Tuple <BitmapRotation, int>(BitmapRotation.Clockwise270Degrees, ocrResult.Text.Length);
}
}
bitmap.Dispose();
if (bestRotation.Item2 < MinimumNumberOfWords)
{
// very low confidence, could just be random patterns
return(BitmapRotation.None);
}
else
{
return(bestRotation.Item1);
}
}
}
else
{
return(BitmapRotation.None);
}
}
catch (Exception exc)
{
LogService?.Log.Error(exc, "Determining the recommended rotation failed.");
AppCenterService?.TrackError(exc);
return(BitmapRotation.None);
}
}
public ScannerFileFormat(ImageScannerFormat targetFormat)
{
TargetFormat = targetFormat;
FriendlyName = GenerateFriendlyName(TargetFormat);
}
