/// <summary>
/// Image pipeline phase 4: Invoke the user-provided delegate (for example, to display the result in a UI)
/// </summary>
static void DisplayPipelinedImages(IEnumerable <ImageInfo> filteredImages,
Action <ImageInfo> displayFn,
Action <ImageInfo> updateStatisticsFn,
CancellationTokenSource cts)
{
int count = 1;
int duration = 0;
var token = cts.Token;
ImageInfo info = null;
try
{
foreach (ImageInfo infoTmp in filteredImages)
{
info = infoTmp;
if (token.IsCancellationRequested)
{
break;
}
int displayStart = Environment.TickCount;
updateStatisticsFn(info);
DisplayImage(info, count, displayFn, duration);
duration = Environment.TickCount - displayStart;
count = count + 1;
info = null;
}
}
catch (Exception e)
{
cts.Cancel();
if (!(e is OperationCanceledException))
{
throw;
}
}
finally
{
if (info != null)
{
info.Dispose();
}
}
}
/// <summary>
/// Image pipeline phase 1: Load images from disk and put them a queue.
/// </summary>
static void LoadPipelinedImages(IEnumerable <string> fileNames, string sourceDir,
BlockingCollection <ImageInfo> original, CancellationTokenSource cts)
{
int count = 0;
int clockOffset = Environment.TickCount;
var token = cts.Token;
ImageInfo info = null;
try
{
foreach (var fileName in fileNames)
{
if (token.IsCancellationRequested)
{
break;
}
info = LoadImage(fileName, sourceDir, count, clockOffset);
original.Add(info, token);
count += 1;
info = null;
}
}
catch (Exception e)
{
// in case of exception, signal shutdown to other pipeline tasks
cts.Cancel();
if (!(e is OperationCanceledException))
{
throw;
}
}
finally
{
original.CompleteAdding();
if (info != null)
{
info.Dispose();
}
}
}
/// <summary>
/// Image pipeline phase 3: Filter images (give them a speckled appearance by adding Gaussian noise)
/// </summary>
static void FilterPipelinedImages(
BlockingCollection <ImageInfo> thumbnailImages,
BlockingCollection <ImageInfo> filteredImages,
CancellationTokenSource cts)
{
ImageInfo info = null;
try
{
var token = cts.Token;
foreach (ImageInfo infoTmp in
thumbnailImages.GetConsumingEnumerable())
{
info = infoTmp;
if (token.IsCancellationRequested)
{
break;
}
FilterImage(info);
filteredImages.Add(info, token);
info = null;
}
}
catch (Exception e)
{
cts.Cancel();
if (!(e is OperationCanceledException))
{
throw;
}
}
finally
{
filteredImages.CompleteAdding();
if (info != null)
{
info.Dispose();
}
}
}
/// <summary>
/// Run the image processing pipeline.
/// </summary>
/// <param name="fileNames">List of image file names in source directory</param>
/// <param name="sourceDir">Name of directory of source images</param>
/// <param name="displayFn">Display action</param>
/// <param name="cts">Cancellation token</param>
static void RunSequential(IEnumerable <string> fileNames, string sourceDir,
Action <ImageInfo> displayFn, CancellationTokenSource cts)
{
int count = 0;
int clockOffset = Environment.TickCount;
int duration = 0;
var token = cts.Token;
ImageInfo info = null;
try
{
foreach (var fileName in fileNames)
{
if (token.IsCancellationRequested)
{
break;
}
info = LoadImage(fileName, sourceDir, count, clockOffset);
ScaleImage(info);
FilterImage(info);
int displayStart = Environment.TickCount;
DisplayImage(info, count + 1, displayFn, duration);
duration = Environment.TickCount - displayStart;
count += 1;
info = null;
}
}
finally
{
if (info != null)
{
info.Dispose();
}
}
}