private static void Preprocess(string type, string input, FrontalFaceDetector faceDetector, ShapePredictor posePredictor, string output)
{
var imageCount = 0;
var r = new ulong[Size * Size];
var g = new ulong[Size * Size];
var b = new ulong[Size * Size];
var csv = ReadCsv(Path.Combine(input, $"{type}.csv"));
var outputDir = Path.Combine(output, type);
foreach (var kvp in csv)
{
using (var tmp = Dlib.LoadImageAsMatrix <RgbPixel>(Path.Combine(input, type, kvp.Key)))
{
var dets = faceDetector.Operator(tmp);
if (!dets.Any())
{
Console.WriteLine($"Warning: Failed to detect face from '{kvp}'");
continue;
}
// Get max size rectangle. It could be better face.
var det = dets.Select((val, idx) => new { V = val, I = idx }).Aggregate((max, working) => (max.V.Area > working.V.Area) ? max : working).V;
using (var ret = posePredictor.Detect(tmp, det))
using (var chip = Dlib.GetFaceChipDetails(ret, Size, 0d))
using (var faceChips = Dlib.ExtractImageChip <RgbPixel>(tmp, chip))
{
var dst = Path.Combine(outputDir, kvp.Key);
var dstDir = Path.GetDirectoryName(dst);
Directory.CreateDirectory(dstDir);
Dlib.SaveJpeg(faceChips, Path.Combine(outputDir, kvp.Key), 100);
var index = 0;
for (var row = 0; row < Size; row++)
{
for (var col = 0; col < Size; col++)
{
var rgb = faceChips[row, col];
r[index] += rgb.Red;
g[index] += rgb.Green;
b[index] += rgb.Blue;
index++;
}
}
}
imageCount++;
}
}
using (var mean = new Matrix <RgbPixel>(Size, Size))
{
var index = 0;
for (var row = 0; row < Size; row++)
{
for (var col = 0; col < Size; col++)
{
var red = (double)r[index] / imageCount;
var green = (double)g[index] / imageCount;
var blue = (double)b[index] / imageCount;
var newRed = (byte)Math.Round(red);
var newGreen = (byte)Math.Round(green);
var newBlue = (byte)Math.Round(blue);
mean[row, col] = new RgbPixel(newRed, newGreen, newBlue);
index++;
}
}
Dlib.SaveBmp(mean, Path.Combine(output, $"{type}.mean.bmp"));
}
}
