bcs-spl-1.5-1.rar_dct_dwt图像压缩_dwt稀疏_图像稀疏基_稀疏基

/* Resampling along the column (Type 1 and 2) * * Created by: Minh N. Do, March 2000 */ #include "mex.h" /* function y = resampc(x, type, shift, extmod) % RESAMPC Resampling along the column % % y = resampc(x, type, shift, extmod) % % Input: % x: image that is extendable along the column direction % type: either 1 or 2 (1 for shuffering down and 2 for up) % shift: amount of shifts (typically 1) % extmod: extension mode: % 'per' periodic % 'ref1' reflect about the edge pixels % 'ref2' reflect, doubling the edge pixels % % Output: % y: resampled image with: % R1 = [1, shift; 0, 1] or R2 = [1, -shift; 0, 1] */ void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[]) { double *x, *px; /* input matrix and pointer */ double *y, *py; /* result matrix and pointer */ int type; /* type of resampling */ int s; /* amount of shifts */ char extmod[10]; /* extension mode */ int i, j, k, m, n; /* Parse input */ if (nrhs < 4) mexErrMsgTxt("Not enough input for RESAMPC!"); x = mxGetPr(prhs[0]); m = mxGetM(prhs[0]); n = mxGetN(prhs[0]); type = (int) mxGetPr(prhs[1])[0]; if ((type != 1) && (type != 2)) mexErrMsgTxt("The second input (type) must be either 1 or 2"); s = (int) mxGetPr(prhs[2])[0]; if (!mxIsChar(prhs[3])) mexErrMsgTxt("EXTMOD arg must be a string"); mxGetString(prhs[3], extmod, 10); /* Create output */ plhs[0] = mxCreateDoubleMatrix(m, n, mxREAL); y = mxGetPr(plhs[0]); px = x; py = y; if (strcmp(extmod, "per") == 0) { /* Resampling column-wise: * y[i, j] = x[<i+sj>, j] if type == 1 * y[i, j] = x[<i-sj>, j] if type == 2 */ for (j = 0; j < n; j++) { /* Circular shift in each column */ if (type == 1) k = (s * j) % m; else k = (-s * j) % m; /* Convert to non-negative mod if needed */ if (k < 0) k += m; for (i = 0; i < m; i++) { if (k >= m) k -= m; py[i] = px[k]; k++; } px += m; py += m; } } else mexErrMsgTxt("Invalid EXTMOD"); }