| 140 |
|
will return a negative value, and |
| 141 |
|
.I S(n) |
| 142 |
|
will return zero. |
| 143 |
+ |
The first input picture with a view is assumed to correspond to the |
| 144 |
+ |
view of the output picture, which is written into the header. |
| 145 |
|
.PP |
| 146 |
|
The |
| 147 |
|
.I \-h |
| 200 |
|
.SH EXAMPLES |
| 201 |
|
To produce a picture showing the difference between pic1 and pic2: |
| 202 |
|
.IP "" .2i |
| 203 |
< |
pcomb -e 'ro=ri(1)-ri(2);go=gi(1)-gi(2);bo=bi(1)-bi(2)' pic1 pic2 > diff |
| 203 |
> |
pcomb \-e 'ro=ri(1)\-ri(2);go=gi(1)\-gi(2);bo=bi(1)\-bi(2)' pic1 pic2 > diff |
| 204 |
|
.PP |
| 205 |
|
Or, more efficiently: |
| 206 |
|
.IP "" .2i |
| 207 |
< |
pcomb pic1 -s -1 pic2 > diff |
| 207 |
> |
pcomb pic1 \-s \-1 pic2 > diff |
| 208 |
|
.PP |
| 209 |
|
To precompute the gamma correction for a picture: |
| 210 |
|
.IP "" .2i |
| 211 |
< |
pcomb -e 'ro=ri(1)^.4;go=gi(1)^.4;bo=bi(1)^.4' pic > pic.gam |
| 211 |
> |
pcomb \-e 'ro=ri(1)^.4;go=gi(1)^.4;bo=bi(1)^.4' inp.hdr > gam.hdr |
| 212 |
|
.PP |
| 213 |
|
To perform some special filtering: |
| 214 |
|
.IP "" .2i |
| 215 |
< |
pcomb -f myfilt.cal -x xmax/2 -y ymax/2 input.pic > filtered.pic |
| 215 |
> |
pcomb \-f myfilt.cal \-x xmax/2 \-y ymax/2 input.hdr > filtered.hdr |
| 216 |
|
.PP |
| 217 |
|
To make a picture of a dot: |
| 218 |
|
.IP "" .2i |
| 219 |
< |
pcomb -x 100 -y 100 -e 'ro=b;go=b;bo=b;b=if((x-50)^2+(y-50)^2-25^2,0,1)' > dot |
| 219 |
> |
pcomb \-x 100 \-y 100 \-e 'ro=b;go=b;bo=b;b=if((x-50)^2+(y-50)^2\-25^2,0,1)' > dot |
| 220 |
|
.SH AUTHOR |
| 221 |
|
Greg Ward |
| 222 |
|
.SH "SEE ALSO" |
