Displaying 2 results from an estimated 2 matches for "postscriptsetcol".
2008 May 23
0
rgb to cmyk conversion is wrong in src/library/grDevices/src/devPS.c (PR#11509)
The conversion of RGB to CMYK takes place in PostScriptSetCol() starting at
line 2900 of R-2.7.0/src/library/grDevices/src/devPS.c
if(strcmp(mm, "cmyk") == 0) {
double c = 1.0-r, m=1.0-g, y=1.0-b, k=c;
k = fmin2(k, m);
k = fmin2(k, y);
if(k == 1.0) c = m = y = 0.0;
else {c /= (1.-k); m /= (1.-k); y /= (1.-k);}
r, g, and b...
2008 May 27
1
(PR#11509) rgb to cmyk conversion is wrong in
...to
CMYK, and so it is wrong to call any method 'wrong' -- in fact the one
used in earlier versions of R was a documented method and within the
family described in the PDF reference manual.
On Fri, 23 May 2008, m1jjh00 at frb.gov wrote:
> The conversion of RGB to CMYK takes place in PostScriptSetCol() starting at
> line 2900 of R-2.7.0/src/library/grDevices/src/devPS.c
>
> if(strcmp(mm, "cmyk") == 0) {
> double c = 1.0-r, m=1.0-g, y=1.0-b, k=c;
> k = fmin2(k, m);
> k = fmin2(k, y);
> if(k == 1.0) c = m = y = 0.0;
> else {c /= (1.-k);...