void Convolve(CImageOf<T> src, CImageOf<T>& dst, CFloatImage kernel) { // Determine the shape of the kernel and source image CShape kShape = kernel.Shape(); CShape sShape = src.Shape(); // Allocate the result, if necessary dst.ReAllocate(sShape, false); if (sShape.width * sShape.height * sShape.nBands == 0) return; // Do the convolution for (int y = 0; y < sShape.height; y++) for (int x = 0; x < sShape.width; x++) for (int c = 0; c < sShape.nBands; c++) { double sum = 0; for (int kx = 0; kx < kShape.width; kx++) for (int ky = 0; ky < kShape.height; ky++) if ((x-kernel.origin[0]+kx >= 0) && (x-kernel.origin[0]+kx < sShape.width) && (y-kernel.origin[1]+ky >= 0) && (y-kernel.origin[1]+ky < sShape.height)) sum += kernel.Pixel(kx,ky,0) * src.Pixel(x-kernel.origin[0]+kx,y-kernel.origin[1]+ky,c); dst.Pixel(x,y,c) = (T) __max(dst.MinVal(), __min(dst.MaxVal(), sum)); } }
void WarpGlobal(CImageOf<T> src, CImageOf<T>& dst, CTransform3x3 M, EWarpInterpolationMode interp, float cubicA) { // Not implemented yet, since haven't decided on semantics of M yet... // Check that dst is of a valid shape if (dst.Shape().width == 0) dst.ReAllocate(src.Shape()); CShape sh = dst.Shape(); // Allocate a row buffer for coordinates int n = sh.width; std::vector<float> rowBuf; rowBuf.resize(n*2); // Precompute the cubic interpolant if (interp == eWarpInterpCubic) InitializeCubicLUT(cubicA); // Process each row for (int y = 0; y < sh.height; y++) { float *xyP = &rowBuf[0]; T *dstP = &dst.Pixel(0, y, 0); // Compute pixel coordinates float X0 = (float) (M[0][1]*y + M[0][2]); float dX = (float) (M[0][0]); float Y0 = (float) (M[1][1]*y + M[1][2]); float dY = (float) (M[1][0]); float Z0 = (float) (M[2][1]*y + M[2][2]); float dZ = (float) (M[2][0]); bool affine = (dZ == 0.0); float Zi = 1.0f / Z0; // TODO: doesn't guard against divide by 0 if (affine) { X0 *= Zi, dX *= Zi, Y0 *= Zi, dY *= Zi; } for (int x = 0; x < n; x++) { xyP[2*x+0] = X0 * Zi; xyP[2*x+1] = Y0 * Zi; X0 += dX; Y0 += dY; if (! affine) { Z0 += dZ; Zi = 1.0f / Z0; } } // Resample the line WarpLine(src, dstP, xyP, n, sh.nBands, interp, src.MinVal(), src.MaxVal()); } }
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); } } }
void WarpLocal(CImageOf<T> src, CImageOf<T>& dst, CFloatImage uv, bool relativeCoords, EWarpInterpolationMode interp, float cubicA) { // Check that dst is of the right shape CShape sh(uv.Shape().width, uv.Shape().height, src.Shape().nBands); dst.ReAllocate(sh); // Allocate a row buffer for coordinates int n = sh.width; std::vector<float> rowBuf; rowBuf.resize(n*2); // Precompute the cubic interpolant if (interp == eWarpInterpCubic) InitializeCubicLUT(cubicA); // Process each row for (int y = 0; y < sh.height; y++) { float *uvP = &uv .Pixel(0, y, 0); float *xyP = (relativeCoords) ? &rowBuf[0] : uvP; T *dstP = &dst.Pixel(0, y, 0); // Convert to absolute coordinates if necessary if (relativeCoords) { for (int x = 0; x < n; x++) { xyP[2*x+0] = x + uvP[2*x+0]; xyP[2*x+1] = y + uvP[2*x+1]; } } // Resample the line WarpLine(src, dstP, xyP, n, sh.nBands, interp, src.MinVal(), src.MaxVal()); } }
extern void ForwardWarp(CImageOf<T>& src, CImageOf<T>& dst, CFloatImage& disp, float d_scale, bool line_interpolate, float disp_gap) { // 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; float round_offset = (typeid(T) == typeid(float)) ? 0.0f : 0.5f; if (! sh.SameIgnoringNBands(disp.Shape())) throw CError("ForwardWarp: disparity image has wrong size"); if (sh != dst.Shape()) dst.ReAllocate(sh); // Optional clipping (if necessary) CFloatImage flt; T minVal = dst.MinVal(); T maxVal = dst.MaxVal(); if (minVal <= flt.MinVal() && maxVal >= flt.MaxVal()) minVal = maxVal = 0; for (int y = 0; y < h; y++) { // determine correct warping direction int xstart = (d_scale>0 ? 0 : w-1); int xend = (d_scale>0 ? w : -1 ); int xincr = (d_scale>0 ? 1 : -1 ); float *dp = &disp.Pixel(0, y, 0); T *ps = &src .Pixel(0, y, 0); T *pd = &dst .Pixel(0, y, 0); for (int x = xstart; x != xend; x += xincr) { // determine if a line should be drawn int x2 = x + xincr; float d_diff = fabs(dp[x] - dp[x2]); bool draw_line = line_interpolate && (x2 != xend) && (d_diff < disp_gap); // scaled disparity: float d = d_scale * dp[x]; // line drawing if (draw_line) { float d2 = d_scale * dp[x2]; if (xincr > 0) draw_intensity_line(&ps[x * n_bands], &ps[x2 * n_bands], pd, x - d, x2 - d2, w, n_bands, round_offset, minVal, maxVal); else draw_intensity_line(&ps[x2 * n_bands], &ps[x * n_bands], pd, x2 - d, x - d2, w, n_bands, round_offset, minVal, maxVal); continue; } // splatting int xx = x - ROUND(d); if (xx >= 0 && xx < w) memcpy(&pd[xx * n_bands], &ps[x * n_bands], n_bands*sizeof(T)); } } }
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); } }