| 143 |
|
is specified for an input picture or the |
| 144 |
|
.I "-fc" |
| 145 |
|
option is given, the output will be written as a RGBE or XYZE picture. |
| 146 |
< |
Note that conversion from a float or RGBE color space applies a conversion |
| 146 |
> |
Note that conversion from a float or RGBE color space applies an efficacy factor |
| 147 |
|
of 179 lumens/watt (for CIE or melanopic output) or 412 (for scotopic output), |
| 148 |
< |
and the reverse happens for conversion from XYZE input to RGB or RGBE output. |
| 148 |
> |
and the inverse happens for conversion from XYZE input to RGB or RGBE output. |
| 149 |
|
Lower case versions of all these components are also supported, the only |
| 150 |
< |
difference is that the aforementioned efficacy factors |
| 151 |
< |
will be left out of the conversion. |
| 150 |
> |
difference being that the efficacy factors are ignored. |
| 151 |
|
.PP |
| 152 |
|
If a matrix or picture file path is given to the |
| 153 |
|
.I \-c |
| 259 |
|
especially for matrix multiplication |
| 260 |
|
and complex operations on long input rows. |
| 261 |
|
.SH EXAMPLES |
| 262 |
< |
To convert two hyperspectral inputs to RGB color space, |
| 262 |
> |
To convert two hyperspectral pictures to RGB color space, |
| 263 |
|
average them together, and write them out as a RADIANCE picture: |
| 264 |
|
.IP "" .2i |
| 265 |
< |
rcomb -C RGB -s .5 img1.spc -s .5 img2.spc > avg.hdr |
| 265 |
> |
rcomb -C RGB -s .5 img1.hsr -s .5 -fc img2.hsr > avg.hdr |
| 266 |
|
.PP |
| 267 |
|
Divide one set of matrix elements by the Euclidean sum of two others: |
| 268 |
|
.IP "" .2i |
| 272 |
|
Compute the absolute and relative differences between melanopic and photopic values |
| 273 |
|
in a spectral image: |
| 274 |
|
.IP "" .2i |
| 275 |
< |
rcomb -fa -C MY -e "abs(x):if(x,x,-x)" |
| 275 |
> |
rcomb -C MY -e "abs(x):if(x,x,-x)" |
| 276 |
|
-e "co(p)=select(p,abs(ci(1,1)-ci(1,2)),(ci(1,1)-ci(1,2))/ci(1,2))" |
| 277 |
< |
input_spec.hsr > compare.mtx |
| 277 |
> |
input_spec.hsr -fa > compare.mtx |
| 278 |
|
.PP |
| 279 |
|
Concatenate a spectral flux coefficient matrix with a spectral sky |
| 280 |
|
matrix to compute a set of melanopic lux values: |
| 339 |
|
.I rcomb, |
| 340 |
|
and should instead be handled by |
| 341 |
|
.I pfilt(1). |
| 342 |
+ |
.PP |
| 343 |
+ |
Similar to |
| 344 |
+ |
.I rmtxop, |
| 345 |
+ |
all calculations are peformed internally using 32-bit floating-point, |
| 346 |
+ |
so there is little benefit in either reading or writing 64-bit double |
| 347 |
+ |
data. |
| 348 |
+ |
This may be overridden at compile time using the macro |
| 349 |
+ |
"-DDTrmx_native=DTdouble". |
| 350 |
|
.SH BUGS |
| 351 |
|
The |
| 352 |
|
.I rcomb |
| 357 |
|
Greg Ward |
| 358 |
|
.SH "SEE ALSO" |
| 359 |
|
dctimestep(1), icalc(1), getinfo(1), pcomb(1), pfilt(1), |
| 360 |
< |
ra_xyze(1), rcalc(1), |
| 360 |
> |
pvsum(1), ra_rgbe(1), ra_xyze(1), rcalc(1), |
| 361 |
|
rcollate(1), rcontrib(1), rcrop(1), rfluxmtx(1), |
| 362 |
|
rmtxop(1), rtpict(1), rtrace(1), vwrays(1) |
