[GRASS-SVN] r44071 - grass/trunk/lib/raster
svn_grass at osgeo.org
svn_grass at osgeo.org
Thu Oct 28 13:04:48 EDT 2010
Author: mmetz
Date: 2010-10-28 10:04:48 -0700 (Thu, 28 Oct 2010)
New Revision: 44071
Modified:
grass/trunk/lib/raster/interp.c
Log:
clean up cubic bspline, try to optimize lanczos
Modified: grass/trunk/lib/raster/interp.c
===================================================================
--- grass/trunk/lib/raster/interp.c 2010-10-28 16:51:41 UTC (rev 44070)
+++ grass/trunk/lib/raster/interp.c 2010-10-28 17:04:48 UTC (rev 44071)
@@ -54,43 +54,44 @@
DCELL Rast_interp_lanczos(double u, double v, DCELL *c)
{
- int i, j;
- double uweight, vweight[5], d;
- DCELL result = 0;
+ int i;
+ double uweight[5], vweight[5], d;
for (i = 0; i < 5; i++) {
+ d = v - i + 2;
+ if (d == 0)
+ vweight[i] = 1;
+ else {
+ d *= M_PI;
+ vweight[i] = LANCZOS_FILTER(d);
+ }
d = u - i + 2;
if (d == 0)
- uweight = 1;
+ uweight[i] = 1;
else {
d *= M_PI;
- uweight = LANCZOS_FILTER(d);
+ uweight[i] = LANCZOS_FILTER(d);
}
+ }
- for (j = 0; j < 5; j++) {
- if (i == 0) {
- d = v - j + 2;
- if (d == 0)
- vweight[j] = 1;
- else {
- d *= M_PI;
- vweight[j] = LANCZOS_FILTER(d);
- }
- }
-
- result += *(c++) * uweight * vweight[j];
- }
- }
-
- return result;
+ return ((c[0] * vweight[0] + c[1] * vweight[1] + c[2] * vweight[2]
+ + c[3] * vweight[3] + c[4] * vweight[4]) * uweight[0] +
+ (c[5] * vweight[0] + c[6] * vweight[1] + c[7] * vweight[2]
+ + c[8] * vweight[3] + c[9] * vweight[4]) * uweight[1] +
+ (c[10] * vweight[0] + c[11] * vweight[1] + c[12] * vweight[2]
+ + c[13] * vweight[3] + c[14] * vweight[4]) * uweight[2] +
+ (c[15] * vweight[0] + c[16] * vweight[1] + c[17] * vweight[2]
+ + c[18] * vweight[3] + c[19] * vweight[4]) * uweight[3] +
+ (c[20] * vweight[0] + c[21] * vweight[1] + c[22] * vweight[2]
+ + c[23] * vweight[3] + c[24] * vweight[4]) * uweight[4]);
}
DCELL Rast_interp_cubic_bspline(double u, DCELL c0, DCELL c1, DCELL c2, DCELL c3)
{
- return (u * (u * (u * ( 1 * c3 - 3 * c2 + 3 * c1 - 1 * c0) +
- ( 0 * c3 + 3 * c2 - 6 * c1 + 3 * c0)) +
- ( 0 * c3 + 3 * c2 + 0 * c1 - 3 * c0)) +
- 0 * c3 + 1 * c2 + 4 * c1 + 1 * c0) / 6;
+ return (u * (u * (u * (c3 - 3 * c2 + 3 * c1 - c0) +
+ (3 * c2 - 6 * c1 + 3 * c0)) +
+ (3 * c2 - 3 * c0)) +
+ c2 + 4 * c1 + c0) / 6;
}
DCELL Rast_interp_bicubic_bspline(double u, double v,
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