public SlicePicker(IFilter grayscaleFilter, IInPlaceFilter edgeDetectionFilter, SliceRatingCalculator ratingCalculator, ThumbnailGeneratorUtilities thumbnailGeneratorUtilities)
{
this.grayscaleFilter = grayscaleFilter;
this.edgeDetectionFilter = edgeDetectionFilter;
this.ratingCalculator = ratingCalculator;
this.thumbnailGeneratorUtilities = thumbnailGeneratorUtilities;
}
public void GenerateThumbnails(ThumbnailGenerationParameters parameters)
{
var textureConverterFactory = new TextureConverterFactory();
using (var textureConverter = textureConverterFactory.Create()) {
IFilter grayscaleFilter = new Grayscale(0.3, 0.59, 0.11);
IInPlaceFilter edgeDetectionFilter = new HomogenityEdgeDetector();
SliceRatingCalculator ratingCalculator = new SliceRatingCalculator();
var utilities = new ThumbnailGeneratorUtilities(textureConverter);
var slicePicker = new SlicePicker(grayscaleFilter, edgeDetectionFilter, ratingCalculator, utilities);
var aspectRatio = 16 / (double)9;
var sliceCount = 5;
var resultWidth = 400;
var resultHeight = (int)(resultWidth / aspectRatio);
var sliceWidth = resultWidth / sliceCount;
var bitmaps = utilities.EnumerateBitmapsRandomly(parameters.SourceDirectory).Take(100).ToList();
var slices = slicePicker.PickSlices(bitmaps, new Size(sliceWidth, resultHeight));
var sliceCombiner = new SliceCombiner(utilities, grayscaleFilter);
for (var i = 0; i < parameters.ThumbnailsToGenerate; i++) {
var bitmap = sliceCombiner.CombineSlices(slices, kSlicesPerThumbnail);
using (var ms = new MemoryStream()) {
bitmap.Save(ms, ImageFormat.Jpeg);
ms.Position = 0;
var hash = MD5.Create().ComputeHash(ms).ToHex();
var outputName = hash + "_" + DateTime.UtcNow.GetUnixTime().ToString() + ".jpg";
var outputPath = Path.Combine(parameters.DestinationDirectory, outputName);
ms.Position = 0;
using (var fs = File.OpenWrite(outputPath)) {
ms.CopyTo(fs);
}
}
}
}
}
/// <summary>
/// Must be run at end of slice selection algorithm.
/// </summary>
/// <param name="imagesAndHistogram"></param>
/// <param name="utilities"></param>
public static unsafe void ShowSliceSelectionDebugImage(ImagesAndHistogram imagesAndHistogram, ThumbnailGeneratorUtilities utilities)
{
var edgeImage = imagesAndHistogram.EdgeImage;
var edgeDensityHistogram = imagesAndHistogram.EdgeDensityHistogram;
DrawHistogram(edgeImage, edgeDensityHistogram);
DrawVerticalLine(edgeImage, edgeDensityHistogram.Median, 254);
DrawVerticalLine(edgeImage, (int)edgeDensityHistogram.Mean, 253);
DrawVerticalLine(edgeImage, (int)(edgeDensityHistogram.Median - edgeDensityHistogram.StdDev), 252);
DrawVerticalLine(edgeImage, (int)(edgeDensityHistogram.Median + edgeDensityHistogram.StdDev), 252);
var resultAspect = 16.0 / 10.0;
var sliceCount = 4;
var sliceAspect = resultAspect / sliceCount;
var desiredWidth = (int)(edgeImage.Height * sliceAspect);
var range = utilities.GetRangeOfWidth(edgeDensityHistogram, desiredWidth);
DrawVerticalLine(edgeImage, range.Min, 250);
DrawVerticalLine(edgeImage, range.Max, 250);
ShowImage(edgeImage);
Application.Run();
}
public SliceCombiner(ThumbnailGeneratorUtilities thumbnailGeneratorUtilities, IFilter grayscaleFilter)
{
this.thumbnailGeneratorUtilities = thumbnailGeneratorUtilities;
this.grayscaleFilter = grayscaleFilter;
}
