void Convolve(CImageOf<T> src, CImageOf<T>& dst,
CFloatImage kernel,
float scale, float offset)
{
// Determine the shape of the kernel and row buffer
CShape kShape = kernel.Shape();
CShape sShape = src.Shape();
CShape bShape(sShape.width + kShape.width, kShape.height, sShape.nBands);
int bWidth = bShape.width * bShape.nBands;
// Allocate the result, if necessary, and the row buffer
dst.ReAllocate(sShape, false);
CFloatImage buffer(bShape);
if (sShape.width * sShape.height * sShape.nBands == 0)
return;
CFloatImage output(CShape(sShape.width, 1, sShape.nBands));
// Fill up the row buffer initially
for (int k = 0; k < kShape.height; k++)
FillRowBuffer(&buffer.Pixel(0, k, 0), src, kernel, k, bWidth);
// Determine if clipping is required
// (we assume up-conversion to float never requires clipping, i.e.,
// floats have the highest dynamic range)
T minVal = dst.MinVal();
T maxVal = dst.MaxVal();
if (minVal <= buffer.MinVal() && maxVal >= buffer.MaxVal())
minVal = maxVal = 0;
// Process each row
for (int y = 0; y < sShape.height; y++)
{
// Do the convolution
ConvolveRow2D(buffer, kernel, &output.Pixel(0, 0, 0),
sShape.width);
// Scale, offset, and type convert
ScaleAndOffsetLine(&output.Pixel(0, 0, 0), &dst.Pixel(0, y, 0),
sShape.width * sShape.nBands,
scale, offset, minVal, maxVal);
// Shift up the row buffer and fill the last line
if (y < sShape.height-1)
{
int k;
for (k = 0; k < kShape.height-1; k++)
memcpy(&buffer.Pixel(0, k, 0), &buffer.Pixel(0, k+1, 0),
bWidth * sizeof(float));
FillRowBuffer(&buffer.Pixel(0, k, 0), src, kernel, y+k+1, bWidth);
}
}
}
extern void InverseWarp(CImageOf<T>& src, CImageOf<T>& dst, CFloatImage& disp,
float d_scale, float disp_gap, int order)
{
// Warps src into dst using disparities disp.
// Each disparity is scaled by d_scale
// Note that "empty" pixels are left at their original value
CShape sh = src.Shape();
int w = sh.width, h = sh.height, n_bands = sh.nBands;
int n = w * n_bands;
if (! sh.SameIgnoringNBands(disp.Shape()))
throw CError("InverseWarp: disparity image has wrong size");
if (sh != dst.Shape())
dst.ReAllocate(sh);
// Optional forward warped depth map if checking for visibility
CFloatImage fwd, fwd_tmp;
if (disp_gap > 0.0f)
{
ScaleAndOffset(disp, fwd_tmp, d_scale, 0.0f);
fwd.ReAllocate(disp.Shape());
fwd.FillPixels(-9999.0f);
ForwardWarp(fwd_tmp, fwd, disp, d_scale, true, disp_gap);
}
// Allocate line buffers
std::vector<float> src_buf, dst_buf, dsp_buf;
src_buf.resize(n);
dst_buf.resize(n);
dsp_buf.resize(n);
CFloatImage fimg; // dummy, used for MinVal(), MaxVal()
for (int y = 0; y < h; y++)
{
// Set up (copy) the line buffers
ScaleAndOffsetLine(&src .Pixel(0, y, 0), &src_buf[0], n,
1.0f, 0.0f, fimg.MinVal(), fimg.MaxVal());
ScaleAndOffsetLine(&disp.Pixel(0, y, 0), &dsp_buf[0], w,
d_scale, 0.0f, 0.0f, 0.0f);
ScaleAndOffsetLine(&dst .Pixel(0, y, 0), &dst_buf[0], n,
1.0f, 0.0f, fimg.MinVal(), fimg.MaxVal());
// Forward warp the depth map
float *fwd_buf = (disp_gap > 0.0f) ? &fwd.Pixel(0, y, 0) : 0;
// Process (warp) the line
InverseWarpLine(&src_buf[0], &dst_buf[0], &dsp_buf[0],
w, n_bands, order, fwd_buf, disp_gap);
// Convert back to native type
T minVal = dst.MinVal();
T maxVal = dst.MaxVal();
float offset = (typeid(T) == typeid(float)) ? 0.0f : 0.5; // rounding
if (minVal <= fimg.MinVal() && maxVal >= fimg.MaxVal())
minVal = maxVal = 0;
ScaleAndOffsetLine(&dst_buf[0], &dst.Pixel(0, y, 0), n,
1.0f, offset, minVal, maxVal);
}
}
