public OcrResult ProcessImage(Image image, string langCode)
{
string tempImageFilePath = Path.Combine(Paths.Temp, Path.GetRandomFileName());
string tempHocrFilePath = Path.Combine(Paths.Temp, Path.GetRandomFileName());
try
{
image.Save(tempImageFilePath);
var startInfo = new ProcessStartInfo
{
FileName = Path.Combine(ocrDependencyManager.GetExecutableDir().FullName, "tesseract.exe"),
Arguments = string.Format("\"{0}\" \"{1}\" hocr -l {2}", tempImageFilePath, tempHocrFilePath, langCode),
UseShellExecute = false,
CreateNoWindow = true
};
var tessdataParent = ocrDependencyManager.GetLanguageDir().Parent;
if (tessdataParent != null)
{
startInfo.EnvironmentVariables["TESSDATA_PREFIX"] = tessdataParent.FullName;
}
EnsureHocrConfigExists();
var tesseractProcess = Process.Start(startInfo);
if (tesseractProcess == null)
{
// Couldn't start tesseract for some reason
Log.Error("Couldn't start OCR process.");
return(null);
}
if (!tesseractProcess.WaitForExit(TESSERACT_TIMEOUT_MS))
{
Log.Error("OCR process timed out.");
try
{
tesseractProcess.Kill();
}
catch (Exception e)
{
Log.ErrorException("Error killing OCR process", e);
}
return(null);
}
XDocument hocrDocument = XDocument.Load(tempHocrFilePath + ".html");
return(new OcrResult
{
Elements = hocrDocument.Descendants()
.Where(x => x.Attributes("class").Any(y => y.Value == "ocrx_word"))
.Select(x => new OcrResultElement {
Text = x.Value, Bounds = GetBounds(x.Attribute("title"))
})
});
}
catch (Exception e)
{
Log.ErrorException("Error running OCR", e);
return(null);
}
finally
{
File.Delete(tempImageFilePath);
File.Delete(tempHocrFilePath + ".html");
}
}
public OcrResult ProcessImage(Image image, string langCode)
{
bool newTesseract = ocrDependencyManager.IsNewExecutableDownloaded;
string tempImageFilePath = Path.Combine(Paths.Temp, Path.GetRandomFileName());
string tempHocrFilePath = Path.Combine(Paths.Temp, Path.GetRandomFileName());
string tempHocrFilePathWithExt = tempHocrFilePath + (newTesseract ? ".hocr" : ".html");
try
{
image.Save(tempImageFilePath);
var exeDir = newTesseract ? ocrDependencyManager.GetExecutableDir() : ocrDependencyManager.GetOldExecutableDir();
var startInfo = new ProcessStartInfo
{
FileName = Path.Combine(exeDir.FullName, "tesseract.exe"),
Arguments = string.Format("\"{0}\" \"{1}\" -l {2} hocr", tempImageFilePath, tempHocrFilePath, langCode),
UseShellExecute = false,
CreateNoWindow = true,
RedirectStandardOutput = true,
RedirectStandardError = true
};
var tessdata = newTesseract ? ocrDependencyManager.GetLanguageDir() : ocrDependencyManager.GetOldLanguageDir();
var tessdataParent = tessdata.Parent;
if (tessdataParent != null)
{
startInfo.EnvironmentVariables["TESSDATA_PREFIX"] = tessdataParent.FullName;
}
EnsureHocrConfigExists(tessdata);
var tesseractProcess = Process.Start(startInfo);
if (tesseractProcess == null)
{
// Couldn't start tesseract for some reason
Log.Error("Couldn't start OCR process.");
return(null);
}
var timeout = (int)(appConfigManager.Config.OcrTimeoutInSeconds * 1000);
if (timeout == 0)
{
timeout = DEFAULT_TIMEOUT;
}
if (!tesseractProcess.WaitForExit(timeout))
{
Log.Error("OCR process timed out.");
try
{
tesseractProcess.Kill();
// Wait a bit to give the process time to release its file handles
Thread.Sleep(200);
}
catch (Exception e)
{
Log.ErrorException("Error killing OCR process", e);
}
return(null);
}
#if DEBUG
var output = tesseractProcess.StandardOutput.ReadToEnd();
if (output.Length > 0)
{
Log.Error("Tesseract stdout: {0}", output);
}
output = tesseractProcess.StandardError.ReadToEnd();
if (output.Length > 0)
{
Log.Error("Tesseract stderr: {0}", output);
}
#endif
XDocument hocrDocument = XDocument.Load(tempHocrFilePathWithExt);
return(new OcrResult
{
Elements = hocrDocument.Descendants()
.Where(x => x.Attributes("class").Any(y => y.Value == "ocrx_word"))
.Select(x => new OcrResultElement {
Text = x.Value, Bounds = GetBounds(x.Attribute("title"))
})
});
}
catch (Exception e)
{
Log.ErrorException("Error running OCR", e);
return(null);
}
finally
{
try
{
File.Delete(tempImageFilePath);
File.Delete(tempHocrFilePathWithExt);
}
catch (Exception e)
{
Log.ErrorException("Error cleaning up OCR temp files", e);
}
}
}
