public void ExtractTrainingData(string vidDir, string vidFileString, bool allFiles)
{
int margin = 5;
int counter = 0;
Random r = new Random();
if (!allFiles) //search for files matching a specific pattern, i.e. actioncliptrain*
{
vidFileString = vidFileString + "*"; //concatenate this into a search pattern so that get files returns only files that match
TrainFiles = Directory.GetFiles(vidDir, vidFileString); //get all the files beginning with vidFileString and anything following. Returns a string[]
}
else
TrainFiles = Directory.GetFiles(vidDir); //get all files in the specified directory. Returns a string[]
Matrix X = new Matrix(SpatialSize * SpatialSize * TemporalSize, TrainFiles.Length * NumPatches);
for (int i = 0; i < TrainFiles.Length; i++) //load in each clip from the list of videos and perform convolution
{
Console.WriteLine("loading clip: {0}", TrainFiles[i]);
Matrix[] M = LoadClip(TrainFiles[i]);
int xDim = M[0].getColumnDimension(); //number of columns = x dimension
int yDim = M[0].getRowDimension(); //number of rows = y dimension
int tDim = M.Length; //number of 2D matrices in M = t dimension
for (int j = 0; j < NumPatches; j++) //convolution step
{
int lowerBound = ++margin;
int upperBound = xDim - margin - SpatialSize + 1;
int xPos = r.Next(lowerBound, upperBound); //unlabeled data, so pick a random x.......
upperBound = yDim - margin - SpatialSize + 1;
int yPos = r.Next(lowerBound, upperBound); //....and a random y....
upperBound = tDim - TemporalSize + 1;
int tPos = r.Next(1, upperBound); //....and a random t within the image boundaries from which to extract features
Matrix[] block = GetBlock(M, xPos, yPos, tPos);
double[] reshapedBlock = Reshape(block, false);
SetColumn(X, counter, reshapedBlock);
counter++;
}
}
}
