| 8 |
|
][ |
| 9 |
|
.B "\-g gamma" |
| 10 |
|
][ |
| 11 |
< |
.B "\-e +/-stops" |
| 11 |
> |
.B "\-e spec" |
| 12 |
> |
][ |
| 13 |
> |
.B "-p xr yr xg yg xb yb xw yw" |
| 14 |
|
] |
| 15 |
|
[ |
| 16 |
|
[ |
| 37 |
|
.SH DESCRIPTION |
| 38 |
|
.I Ra_bmp |
| 39 |
|
converts between RADIANCE and a Windows BMP image. |
| 40 |
< |
The |
| 40 |
> |
During forward conversion, the |
| 41 |
|
.I \-b |
| 42 |
|
option produces 8-bit grayscale output rather than 24-bit RGB. |
| 43 |
|
The |
| 44 |
|
.I \-g |
| 45 |
< |
option specifies the exponent used in gamma correction; |
| 45 |
> |
option specifies the exponent used in monitor gamma correction; |
| 46 |
|
the default value is 2.2. |
| 47 |
|
The |
| 48 |
|
.I \-e |
| 49 |
< |
option specifies an exposure compensation in f-stops (powers of two |
| 50 |
< |
and proceeded by +/-). |
| 51 |
< |
Only integer stops are allowed, for efficiency. |
| 49 |
> |
option specifies a tone-mapping method or exposure compensation. |
| 50 |
> |
If the argument is one of the special words "auto", "human", or "linear", |
| 51 |
> |
the image will be tone-mapped with histogram adjustment, |
| 52 |
> |
human vision simulation, or an averaged linear exposure, |
| 53 |
> |
respectively. |
| 54 |
> |
(These words may be abbreviated by one or more letters.)\0 |
| 55 |
> |
Otherwise, the exposure specification is interpreted as a |
| 56 |
> |
linear compensation value in integer f-stops, which must |
| 57 |
> |
be proceeded by a '+' or '-'. |
| 58 |
> |
The CRT color output primaries may be specified with the |
| 59 |
> |
.I \-p |
| 60 |
> |
option. |
| 61 |
> |
.PP |
| 62 |
|
The |
| 63 |
|
.I \-r |
| 64 |
|
option invokes a reverse conversion, from a Windows BMP image |
| 65 |
|
to a RADIANCE picture. |
| 66 |
+ |
Tone-mapping and monitor primaries are not |
| 67 |
+ |
supported for reverse conversion. |
| 68 |
+ |
.PP |
| 69 |
|
.I Ra_bmp |
| 70 |
|
can accept 16-bit or color-mapped BMP files on input, |
| 71 |
|
but cannot not produce them on output. |
| 74 |
|
either forward or reverse conversion so that an output file may be |
| 75 |
|
specified. |
| 76 |
|
If the BMP input is taken from the standard input or sent to the |
| 77 |
< |
standard output, then the scanlines may be reversed from their |
| 78 |
< |
usual ordering. |
| 79 |
< |
This sometimes causes difficulties for programs attempting |
| 77 |
> |
standard output without tone-mapping, then the scanlines may |
| 78 |
> |
be reversed from their usual ordering. |
| 79 |
> |
Scanlines are also reversed when output to a BMP file without |
| 80 |
> |
tone-mapping using the grayscale option. |
| 81 |
> |
Reversed scanlines sometimes causes difficulties for programs attempting |
| 82 |
|
to interpret the resulting RADIANCE picture or BMP image, which |
| 83 |
|
may be rejected or displayed inverted. |
| 84 |
|
.SH AUTHOR |
