private async Task DoSaveImage(ScannedImage.Snapshot snapshot, string path, ImageFormat format)
{
PathHelper.EnsureParentDirExists(path);
if (Equals(format, ImageFormat.Tiff))
{
await tiffHelper.SaveMultipage(new List <ScannedImage.Snapshot> {
snapshot
}, path, imageSettingsContainer.ImageSettings.TiffCompression, (i, j) => { }, CancellationToken.None);
}
else if (Equals(format, ImageFormat.Jpeg))
{
var quality = Math.Max(Math.Min(imageSettingsContainer.ImageSettings.JpegQuality, 100), 0);
var encoder = ImageCodecInfo.GetImageEncoders().First(x => x.FormatID == ImageFormat.Jpeg.Guid);
var encoderParams = new EncoderParameters(1);
encoderParams.Param[0] = new EncoderParameter(Encoder.Quality, quality);
using (Bitmap bitmap = await scannedImageRenderer.Render(snapshot))
{
bitmap.Save(path, encoder, encoderParams);
}
}
else
{
using (Bitmap bitmap = await scannedImageRenderer.Render(snapshot))
{
bitmap.Save(path, format);
}
}
}
public OcrRequestParams(ScannedImage.Snapshot snapshot, IOcrEngine ocrEngine, OcrParams ocrParams)
{
ScannedImage = snapshot.Source;
TransformState = snapshot.TransformList.Count == 0 ? -1 : snapshot.TransformState;
Engine = ocrEngine;
OcrParams = ocrParams;
}
public async Task <OcrResult> QueueForeground(IOcrEngine ocrEngine, ScannedImage.Snapshot snapshot, string tempImageFilePath, OcrParams ocrParams, CancellationToken cancelToken)
{
OcrRequest req;
lock (this)
{
ocrEngine = ocrEngine ?? ocrManager.ActiveEngine ?? throw new ArgumentException("No OCR engine available");
ocrParams = ocrParams ?? ocrManager.DefaultParams;
var reqParams = new OcrRequestParams(snapshot, ocrEngine, ocrParams);
req = requestCache.GetOrSet(reqParams, () => new OcrRequest(reqParams));
// Fast path for cached results
if (req.Result != null)
{
SafeDelete(tempImageFilePath);
return(req.Result);
}
// Manage ownership of the provided temp file
if (req.TempImageFilePath == null)
{
req.TempImageFilePath = tempImageFilePath;
}
else
{
SafeDelete(tempImageFilePath);
}
// Increment the reference count
req.ForegroundCount += 1;
queueWaitHandle.Release();
}
// If no worker threads are running, start them
EnsureWorkerThreads();
// Wait for completion or cancellation
await Task.Factory.StartNew(() =>
{
try
{
WaitHandle.WaitAny(new[] { req.WaitHandle, cancelToken.WaitHandle });
}
catch (Exception e)
{
Log.ErrorException("Error in OcrRequestQueue.QueueForeground response task", e);
}
}, TaskCreationOptions.LongRunning);
lock (this)
{
// Decrement the reference count
req.ForegroundCount -= 1;
// If all requestors have cancelled and there's no result to cache, delete the request
DestroyRequest(req);
}
// If no requests are pending, stop the worker threads
EnsureWorkerThreads();
// May return null if cancelled
return(req.Result);
}
public byte[] RenderThumbnail(ScannedImage.Snapshot snapshot, int size)
{
var stream = new MemoryStream();
using (var bitmap = Task.Factory.StartNew(() => thumbnailRenderer.RenderThumbnail(snapshot, size)).Unwrap().Result)
{
bitmap.Save(stream, ImageFormat.Png);
}
return(stream.ToArray());
}
public bool HasCachedResult(IOcrEngine ocrEngine, ScannedImage.Snapshot snapshot, OcrParams ocrParams)
{
ocrEngine = ocrEngine ?? ocrManager.ActiveEngine ?? throw new ArgumentException("No OCR engine available");
ocrParams = ocrParams ?? ocrManager.DefaultParams;
var reqParams = new OcrRequestParams(snapshot, ocrEngine, ocrParams);
lock (this)
{
return(requestCache.ContainsKey(reqParams) && requestCache[reqParams].Result != null);
}
}
public void QueueBackground(ScannedImage.Snapshot snapshot, string tempImageFilePath, OcrParams ocrParams)
{
OcrRequest req;
CancellationTokenSource cts = new CancellationTokenSource();
lock (this)
{
var ocrEngine = ocrManager.ActiveEngine;
if (ocrEngine == null)
{
return;
}
ocrParams = ocrParams ?? ocrManager.DefaultParams;
var reqParams = new OcrRequestParams(snapshot, ocrEngine, ocrParams);
req = requestCache.GetOrSet(reqParams, () => new OcrRequest(reqParams));
// Fast path for cached results
if (req.Result != null)
{
return;
}
// Manage ownership of the provided temp file
if (req.TempImageFilePath == null)
{
req.TempImageFilePath = tempImageFilePath;
}
else
{
SafeDelete(tempImageFilePath);
}
// Increment the reference count
req.BackgroundCount += 1;
snapshot.Source.ThumbnailInvalidated += (sender, args) => cts.Cancel();
snapshot.Source.FullyDisposed += (sender, args) => cts.Cancel();
queueWaitHandle.Release();
}
// If no worker threads are running, start them
EnsureWorkerThreads();
var op = StartingOne();
Task.Factory.StartNew(() =>
{
try
{
WaitHandle.WaitAny(new[] { req.WaitHandle, cts.Token.WaitHandle, op.CancelToken.WaitHandle });
lock (this)
{
// Decrement the reference count
req.BackgroundCount -= 1;
// If all requestors have cancelled and there's no result to cache, delete the request
DestroyRequest(req);
}
FinishedOne();
// If no requests are pending, stop the worker threads
EnsureWorkerThreads();
}
catch (Exception e)
{
Log.ErrorException("Error in OcrRequestQueue.QueueBackground response task", e);
}
}, TaskCreationOptions.LongRunning);
}
