/// <summary>
/// Computes a confusion matrix using the soft values from the distributions in <paramref name="inferredLabels"/> based upon the ground truth
/// pixel labels in <paramref name="groundTruth"/>.
/// </summary>
/// <param name="groundTruth">The ground truth labels of the image</param>
/// <param name="inferredLabels">The inferred labels of the image</param>
/// <returns>A confusion matrix</returns>
public static ConfusionMatrix ComputeConfusionMatrix(LabelImage groundTruth, DistributionImage inferredLabels)
{
ConfusionMatrix matrix = new ConfusionMatrix(inferredLabels.Channels);
ComputeConfusionMatrix(matrix, groundTruth, inferredLabels);
return(matrix);
}
/// <summary>
/// Multiplies each pixel's distribution in this image by each pixel's distribution in <paramref name="image"/>.
/// </summary>
/// <param name="image">Image to multiply by</param>
public unsafe void Multiply(DistributionImage image)
{
int rows = Rows;
int columns = Columns;
int channels = Channels;
if (rows != image.Rows || columns != image.Columns || channels != image.Channels)
throw new ArgumentException("Argument must be of same dimensions as image");
fixed(float *dataSrc = RawArray, argSrc = image.RawArray)
{
float *dataPtr = dataSrc;
float *argPtr = argSrc;
for (int r = 0; r < rows; r++)
{
for (int c = 0; c < columns; c++)
{
for (int i = 0; i < channels; i++, dataPtr++, argPtr++)
{
*dataPtr = *dataPtr * *argPtr;
}
}
}
}
}
/// <summary>
/// Subsamples this image.
/// </summary>
/// <param name="subsample">Value to subsample by</param>
/// <returns>The subsampled distribution image</returns>
public unsafe DistributionImage Subsample(int subsample)
{
int rows = Rows;
int columns = Columns;
int channels = Channels;
int stride = columns * channels;
int nRows = rows / subsample;
int nColumns = columns / subsample;
float[, ,] dst = new float[nRows, nColumns, channels];
fixed(float *srcBuf = RawArray, dstBuf = dst)
{
float *srcPtr = srcBuf;
float *dstPtr = dstBuf;
for (int r = 0; r < nRows; r++)
{
float *srcScan = srcPtr;
for (int c = 0; c < nColumns; c++)
{
float *srcScan2 = srcScan;
for (int srcR = 0; srcR < subsample; srcR++)
{
float *srcScan3 = srcScan2;
for (int srcC = 0; srcC < subsample; srcC++)
{
for (int i = 0; i < channels; i++)
{
dstPtr[i] += *srcScan3++;
}
}
srcScan2 += stride;
}
dstPtr += channels;
srcScan += subsample * channels;
}
srcPtr += subsample * stride;
}
}
DistributionImage dist = new DistributionImage();
dist.ID = ID;
dist.SetData(dst);
dist.Normalize();
return(dist);
}
/// <summary>
/// Creates a new distribution image by appending the distributions at each pixel.
/// </summary>
/// <param name="lhs">The first image</param>
/// <param name="rhs">The second image</param>
/// <returns>The appended distribution image</returns>
public static unsafe DistributionImage Append(DistributionImage lhs, DistributionImage rhs)
{
int rows = lhs.Rows;
int columns = lhs.Columns;
int channels0 = lhs.Channels;
int channels1 = rhs.Channels;
if (rhs.Rows != rows || rhs.Columns != columns)
{
throw new ArgumentException("Arguments must be same dimension");
}
DistributionImage combo = new DistributionImage(rows, columns, channels0 + channels1);
fixed(float *lhsSrc = lhs.RawArray, rhsSrc = rhs.RawArray, comboSrc = combo.RawArray)
{
float *lhsPtr = lhsSrc;
float *rhsPtr = rhsSrc;
float *comboPtr = comboSrc;
for (int r = 0; r < rows; r++)
{
for (int c = 0; c < columns; c++)
{
for (int i = 0; i < channels0; i++)
{
*comboPtr++ = *lhsPtr++;
}
for (int i = 0; i < channels1; i++)
{
*comboPtr++ = *rhsPtr++;
}
}
}
}
return(combo);
}
/// <summary>
/// Adds a distribution image to this image, using <paramref name="label"/> to index that image.
/// </summary>
/// <param name="dist">The distribution image to add</param>
/// <param name="label">The label to extract from the image</param>
public unsafe void Add(DistributionImage dist, short label)
{
int numLabels = dist.Channels;
int rows = dist.Rows;
int columns = dist.Columns;
int nRows = Rows;
int nColumns = Columns;
float scaleR = (float)nRows / rows;
float scaleC = (float)nColumns / columns;
float[,] counts = new float[nRows, nColumns];
fixed(float *labelSrc = dist.RawArray)
{
float *labelPtr = labelSrc;
for (int r = 0; r < rows; r++)
{
for (int c = 0; c < columns; c++)
{
float val = labelPtr[label];
float rr = r * scaleR;
float cc = c * scaleC;
int i0 = (int)rr;
int j0 = (int)cc;
float di = rr - i0 - .5f;
float dj = cc - j0 - .5f;
if (di < 0)
{
i0--;
di += 1;
}
if (dj < 0)
{
j0--;
dj += 1;
}
int i1 = i0 + 1;
int j1 = j0 + 1;
if (i0 < 0)
{
i0++;
}
if (i1 == nRows)
{
i1--;
}
if (j0 < 0)
{
j0++;
}
if (j1 == nColumns)
{
j1--;
}
float a = 1 - di;
float b = 1 - dj;
counts[i0, j0] += a * b * val;
counts[i0, j1] += a * dj * val;
counts[i1, j0] += di * b * val;
counts[i1, j1] += di * dj * val;
_sum += val;
_rowSums[i0] += a * val;
_rowSums[i1] += di * val;
_columnSums[j0] += b * val;
_columnSums[j1] += dj * val;
labelPtr += numLabels;
}
}
}
fixed(float *dataSrc = RawArray, countsSrc = counts)
{
float *dataPtr = dataSrc;
float *countsPtr = countsSrc;
int total = Rows * Columns;
while (total-- > 0)
{
*dataPtr = *dataPtr + *countsPtr;
dataPtr++;
countsPtr++;
}
}
}
/// <summary>
/// Computes a confusion matrix using the soft values from the distributions in <paramref name="inferredLabels"/> based upon the ground truth
/// pixel labels in <paramref name="groundTruth"/>, and adds them to <paramref name="matrix"/>.
/// </summary>
/// <param name="matrix">Matrix to add the confusion values of this image to</param>
/// <param name="groundTruth">The ground truth labels of the image</param>
/// <param name="inferredLabels">The inferred labels of the image</param>
public static unsafe void ComputeConfusionMatrix(ConfusionMatrix matrix, LabelImage groundTruth, DistributionImage inferredLabels)
{
int rows = groundTruth.Rows;
int columns = groundTruth.Columns;
int channels = inferredLabels.Channels;
fixed(short *labelsSrc = groundTruth.RawArray)
{
fixed(float *distSrc = inferredLabels.RawArray)
{
short *labelsPtr = labelsSrc;
float *distPtr = distSrc;
for (int r = 0; r < rows; r++)
{
for (int c = 0; c < columns; c++, labelsPtr++)
{
short trueLabel = *labelsPtr;
for (short i = 0; i < channels; i++, distPtr++)
{
matrix.Add(trueLabel, i, *distPtr);
}
}
}
}
}
}
