| 25 |
|
] |
| 26 |
|
.B "m1 .." |
| 27 |
|
[ |
| 28 |
< |
.B "\-m mcat" |
| 28 |
> |
.B "\-m[t] mcat" |
| 29 |
|
] |
| 30 |
|
.SH DESCRIPTION |
| 31 |
|
.I Rcomb |
| 60 |
|
using the |
| 61 |
|
.I \-m |
| 62 |
|
option. |
| 63 |
+ |
If the option is given as |
| 64 |
+ |
.I \-mt |
| 65 |
+ |
then the concatenation matrix will be transposed before it is applied. |
| 66 |
|
Matrix concatenation will happen before or after any trailing |
| 67 |
|
operations, depending on relative command line placement. |
| 68 |
|
.PP |
| 146 |
|
is specified for an input picture or the |
| 147 |
|
.I "-fc" |
| 148 |
|
option is given, the output will be written as a RGBE or XYZE picture. |
| 149 |
< |
Note that conversion from a float or RGBE color space applies a conversion |
| 149 |
> |
Note that conversion from a float or RGBE color space applies an efficacy factor |
| 150 |
|
of 179 lumens/watt (for CIE or melanopic output) or 412 (for scotopic output), |
| 151 |
< |
and the reverse happens for conversion from XYZE input to RGB or RGBE output. |
| 151 |
> |
and the inverse happens for conversion from XYZE input to RGB or RGBE output. |
| 152 |
|
Lower case versions of all these components are also supported, the only |
| 153 |
< |
difference is that the aforementioned efficacy factors |
| 151 |
< |
will be left out of the conversion. |
| 153 |
> |
difference being that the efficacy factors are ignored. |
| 154 |
|
.PP |
| 155 |
|
If a matrix or picture file path is given to the |
| 156 |
|
.I \-c |
| 262 |
|
especially for matrix multiplication |
| 263 |
|
and complex operations on long input rows. |
| 264 |
|
.SH EXAMPLES |
| 265 |
< |
To convert two hyperspectral inputs to RGB color space, |
| 265 |
> |
To convert two hyperspectral pictures to RGB color space, |
| 266 |
|
average them together, and write them out as a RADIANCE picture: |
| 267 |
|
.IP "" .2i |
| 268 |
< |
rcomb -C RGB -s .5 img1.spc -s .5 img2.spc > avg.hdr |
| 268 |
> |
rcomb -C RGB -s .5 img1.hsr -s .5 -fc img2.hsr > avg.hdr |
| 269 |
|
.PP |
| 270 |
|
Divide one set of matrix elements by the Euclidean sum of two others: |
| 271 |
|
.IP "" .2i |
| 275 |
|
Compute the absolute and relative differences between melanopic and photopic values |
| 276 |
|
in a spectral image: |
| 277 |
|
.IP "" .2i |
| 278 |
< |
rcomb -fa -C MY -e "abs(x):if(x,x,-x)" |
| 278 |
> |
rcomb -C MY -e "abs(x):if(x,x,-x)" |
| 279 |
|
-e "co(p)=select(p,abs(ci(1,1)-ci(1,2)),(ci(1,1)-ci(1,2))/ci(1,2))" |
| 280 |
< |
input_spec.hsr > compare.mtx |
| 280 |
> |
input_spec.hsr -fa > compare.mtx |
| 281 |
|
.PP |
| 282 |
|
Concatenate a spectral flux coefficient matrix with a spectral sky |
| 283 |
|
matrix to compute a set of melanopic lux values: |
| 342 |
|
.I rcomb, |
| 343 |
|
and should instead be handled by |
| 344 |
|
.I pfilt(1). |
| 345 |
+ |
.PP |
| 346 |
+ |
Similar to |
| 347 |
+ |
.I rmtxop, |
| 348 |
+ |
all calculations are peformed internally using 32-bit floating-point, |
| 349 |
+ |
so there is little benefit in either reading or writing 64-bit double |
| 350 |
+ |
data. |
| 351 |
+ |
This may be overridden at compile time using the macro |
| 352 |
+ |
"-DDTrmx_native=DTdouble". |
| 353 |
|
.SH BUGS |
| 354 |
|
The |
| 355 |
|
.I rcomb |
| 360 |
|
Greg Ward |
| 361 |
|
.SH "SEE ALSO" |
| 362 |
|
dctimestep(1), icalc(1), getinfo(1), pcomb(1), pfilt(1), |
| 363 |
< |
ra_xyze(1), rcalc(1), |
| 363 |
> |
pvsum(1), ra_rgbe(1), ra_xyze(1), rcalc(1), |
| 364 |
|
rcollate(1), rcontrib(1), rcrop(1), rfluxmtx(1), |
| 365 |
|
rmtxop(1), rtpict(1), rtrace(1), vwrays(1) |
