public PdfRecognitionJob(
IConfiguredTesseractEngineFactory engineFactory,
IStoredImageFile imageFile,
IEnumerable <IPreprocessor> preprocessors,
IPdfDocumentFactory pdfDocumentFactory,
IPixFactory pixFactory,
IImageFileStorage storage)
{
_engineFactory = engineFactory ?? throw new ArgumentNullException(nameof(engineFactory));
_pdfFile = imageFile ?? throw new ArgumentNullException(nameof(imageFile));
_preprocessors = preprocessors ?? throw new ArgumentNullException(nameof(preprocessors));
_pdfDocumentFactory = pdfDocumentFactory ?? throw new ArgumentNullException(nameof(pdfDocumentFactory));
_pixFactory = pixFactory ?? throw new ArgumentNullException(nameof(pixFactory));
_storage = storage ?? throw new ArgumentNullException(nameof(storage));
}
internal ImageRecognitionEngine(
IImageFileTypeRecognizer recognizer,
IImageFileStorage storage,
IRecognitionJobFactory recognitionJobFactory,
IRecognitionJobQueue recognitionJobQueue,
ITesseractEngineFactory tesseractFactory,
IPreprocessorFactory preprocessorFactory)
{
_recognizer = recognizer ?? throw new ArgumentNullException(nameof(recognizer));
_storage = storage ?? throw new ArgumentNullException(nameof(storage));
_jobFactory = recognitionJobFactory ?? throw new ArgumentNullException(nameof(recognitionJobFactory));
_jobQueue = recognitionJobQueue ?? throw new ArgumentNullException(nameof(recognitionJobQueue));
_tesseractFactory = tesseractFactory ?? throw new ArgumentNullException(nameof(tesseractFactory));
_preprocessorFactory = preprocessorFactory ?? throw new ArgumentNullException(nameof(preprocessorFactory));
}
public static async Task <IEnumerable <IStoredImageFile> > ExtractImagesAsync(this PdfDocument document, IImageFileStorage storage)
{
if (storage == null)
{
throw new ArgumentNullException(nameof(storage));
}
var results = new List <IStoredImageFile>();
foreach (var page in document.Pages)
{
var resources = page.Elements.GetDictionary("/Resources");
var xObjects = resources?.Elements.GetDictionary("/XObject");
if (xObjects == null)
{
continue;
}
var items = xObjects.Elements.Values;
foreach (var item in items)
{
var reference = item as PdfReference;
if (!(reference?.Value is PdfDictionary xObject) ||
xObject.Elements.GetString("/Subtype") != "/Image")
{
continue;
}
var path = await TryExportImageAsync(xObject);
if (path == null)
{
continue;
}
var file = storage.Wrap(path);
results.Add(file);
}
}
return(results);
}
public RecognitionJobFactory(IPixFactory pixFactory, IPdfDocumentFactory pdfDocumentFactory, IImageFileStorage storage)
{
_pixFactory = pixFactory ?? throw new ArgumentNullException(nameof(pixFactory));
_pdfDocumentFactory = pdfDocumentFactory ?? throw new ArgumentNullException(nameof(pdfDocumentFactory));
_storage = storage ?? throw new ArgumentNullException(nameof(storage));
}
