public static async Task <UwpSoftwareBitmap> ConvertFrom(BitmapFrame sourceBitmap)
{
// BitmapFrameをBMP形式のバイト配列に変換
byte[] bitmapBytes;
var encoder = new BmpBitmapEncoder(); // .NET用のエンコーダーを使う
encoder.Frames.Add(sourceBitmap);
using (var memoryStream = new MemoryStream())
{
encoder.Save(memoryStream);
bitmapBytes = memoryStream.ToArray();
}
// バイト配列をUWPのIRandomAccessStreamに変換
using (var randomAccessStream = new UwpInMemoryRandomAccessStream())
{
using (var outputStream = randomAccessStream.GetOutputStreamAt(0))
using (var writer = new UwpDataWriter(outputStream))
{
writer.WriteBytes(bitmapBytes);
await writer.StoreAsync();
await outputStream.FlushAsync();
}
// IRandomAccessStreamをSoftwareBitmapに変換
// （UWP APIのデコーダー）
var decoder = await UwpBitmapDecoder.CreateAsync(randomAccessStream);
var softwareBitmap
= await decoder.GetSoftwareBitmapAsync(UwpBitmapPixelFormat.Bgra8, UwpBitmapAlphaMode.Premultiplied);
return(softwareBitmap);
}
}
private static async Task <Bitmap> CreateFromStream(IRandomAccessStream stream)
{
var decoder = await BitmapDecoder.CreateAsync(BitmapDecoder.PngDecoderId, stream);
var frame = await decoder.GetFrameAsync(0);
var pixelData = await frame.GetPixelDataAsync();
var bytes = pixelData.DetachPixelData();
return(new Bitmap
{
Bytes = bytes,
Width = (int)frame.PixelWidth,
Height = (int)frame.PixelHeight,
});
}
public async Task <string> ExtractText(Bitmap bmp, string languageCode, System.Windows.Point?singlePoint = null)
{
if (!GlobalizationPreferences.Languages.Contains(languageCode))
{
throw new ArgumentOutOfRangeException($"{languageCode} is not installed.");
}
StringBuilder text = new StringBuilder();
await using (MemoryStream memory = new MemoryStream())
{
bmp.Save(memory, System.Drawing.Imaging.ImageFormat.Bmp);
memory.Position = 0;
BitmapDecoder bmpDecoder = await BitmapDecoder.CreateAsync(memory.AsRandomAccessStream());
Windows.Graphics.Imaging.SoftwareBitmap softwareBmp = await bmpDecoder.GetSoftwareBitmapAsync();
OcrEngine ocrEngine = OcrEngine.TryCreateFromLanguage(new Language(languageCode));
OcrResult ocrResult = await ocrEngine.RecognizeAsync(softwareBmp);
if (singlePoint == null)
{
foreach (OcrLine line in ocrResult.Lines)
{
text.AppendLine(line.Text);
}
}
else
{
Windows.Foundation.Point fPoint = new Windows.Foundation.Point(singlePoint.Value.X, singlePoint.Value.Y);
foreach (OcrLine ocrLine in ocrResult.Lines)
{
foreach (OcrWord ocrWord in ocrLine.Words)
{
if (ocrWord.BoundingRect.Contains(fPoint))
{
text.Append(ocrWord.Text);
}
}
}
}
}
return(text.ToString());
}
public async Task <string> ExtractText(Bitmap bmp, string languageCode, System.Windows.Point?singlePoint = null)
{
Language selectedLanguage = new Language(languageCode);
List <Language> possibleOCRLangs = OcrEngine.AvailableRecognizerLanguages.ToList();
if (possibleOCRLangs.Count < 1)
{
throw new ArgumentOutOfRangeException($"No possible OCR languages are installed.");
}
if (possibleOCRLangs.Where(l => l.LanguageTag == selectedLanguage.LanguageTag).Count() < 1)
{
List <Language> similarLanguages = possibleOCRLangs.Where(la => la.AbbreviatedName == selectedLanguage.AbbreviatedName).ToList();
if (similarLanguages.Count() > 0)
{
selectedLanguage = similarLanguages.FirstOrDefault();
}
else
{
selectedLanguage = possibleOCRLangs.FirstOrDefault();
}
}
bool scaleBMP = true;
if (singlePoint != null ||
bmp.Width * 1.5 > OcrEngine.MaxImageDimension)
{
scaleBMP = false;
}
Bitmap scaledBitmap;
if (scaleBMP)
{
scaledBitmap = ScaleBitmapUniform(bmp, 1.5);
}
else
{
scaledBitmap = ScaleBitmapUniform(bmp, 1.0);
}
StringBuilder text = new StringBuilder();
XmlLanguage lang = XmlLanguage.GetLanguage(languageCode);
CultureInfo culture = lang.GetEquivalentCulture();
await using (MemoryStream memory = new MemoryStream())
{
scaledBitmap.Save(memory, ImageFormat.Bmp);
memory.Position = 0;
BitmapDecoder bmpDecoder = await BitmapDecoder.CreateAsync(memory.AsRandomAccessStream());
Windows.Graphics.Imaging.SoftwareBitmap softwareBmp = await bmpDecoder.GetSoftwareBitmapAsync();
OcrEngine ocrEngine = OcrEngine.TryCreateFromLanguage(selectedLanguage);
OcrResult ocrResult = await ocrEngine.RecognizeAsync(softwareBmp);
if (singlePoint == null)
{
foreach (OcrLine line in ocrResult.Lines)
{
text.AppendLine(line.Text);
}
}
else
{
Windows.Foundation.Point fPoint = new Windows.Foundation.Point(singlePoint.Value.X, singlePoint.Value.Y);
foreach (OcrLine ocrLine in ocrResult.Lines)
{
foreach (OcrWord ocrWord in ocrLine.Words)
{
if (ocrWord.BoundingRect.Contains(fPoint))
{
text.Append(ocrWord.Text);
}
}
}
}
}
if (culture.TextInfo.IsRightToLeft)
{
List <string> textListLines = text.ToString().Split(new char[] { '\n', '\r' }).ToList();
text.Clear();
foreach (string textLine in textListLines)
{
List <string> wordArray = textLine.Split().ToList();
wordArray.Reverse();
text.Append(string.Join(' ', wordArray));
if (textLine.Length > 0)
{
text.Append('\n');
}
}
return(text.ToString());
}
else
{
return(text.ToString());
}
}
