man/man1/pvalue.1

.\" RCSid "$Id: pvalue.1,v 1.10 2019/07/15 23:42:44 greg Exp $"
.TH PVALUE 1 1/15/99 RADIANCE
.SH NAME
pvalue - convert RADIANCE picture to/from alternate formats
.SH SYNOPSIS
.B pvalue
[
.B options
]
[
.B file
]
.br
.B "pvalue -r"
[
.B options
]
[
.B file1
[
.B "file2 file3"
]
]
.SH DESCRIPTION
.I Pvalue
converts the pixels of a RADIANCE picture to or from another format.
In the default mode, pixels are sent to the
standard output, one per line, in the following ascii format:

        xpos    ypos    red     green   blue

If no
.I file
is given, the standard input is read.
.PP
The reverse conversion option
.I (-r)
may be used with a single input file or when reading from the
standard input, but if the second form is used with three separate
input files, the three primaries are presumed to be separated in
these files.
.TP 10n
.BR \-u
Print only unique values in the output, skipping runs of equal pixels.
For reverse conversions, the
.I \-u
option writes uncompressed output rather than the standard run-length RGBE
encoding.
Specifying
.I \+u
turns this option off, which is the default.
.TP
.BR \-o
Print original values, before exposure compensation.
If the input file is in XYZE format, the Y (green) channel
will correspond to units of candelas/meter^2.
Otherwise, the RGB values should be in spectral watts/steradian/meter^2.
Specifying
.I \+o
uses final exposed values, which is the default.
.TP
.BR \-h
Do not print header.
Specifying
.I \+h
causes the header to be printed, which is the default.
.TP
.BI \-H
Do not print the resolution string.
(See also the
.I \-r
option below.)
Specifying an input resolution for reverse conversion also turns
this option off.
Specifying
.I \+H
causes the resolution string to be printed, which is the default.
.TP
.BI \-s \ nbytes
Skip the specified number of bytes on the input header.
This option is useful for skipping unintelligible headers in
foreign file formats.
.TP
.BI \-e \ exposure
Adjust the exposure by the amount specified.
If the exposure is being given as a conversion factor, use
.I \+e
instead, so an EXPOSURE line will not be recorded in the header
(if any).
.TP
.BI \-g \ gamma
Set gamma correction for conversion.
When converting from a RADIANCE picture to another format,
the inverse gamma is applied to correct for monitor response.
When converting to a RADIANCE picture
.I (\-r
option), the gamma is applied directly to recover the linear values.
By default,
.I gamma
is set to 1.0, meaning no gamma correction is performed.
.TP
.BR \-d
Data only,
do not print x and y pixel position.
.TP
.BR \-da
Same as
.I \-d.
.TP
.BR \-di
Print ascii integer values from 0 to 255+.
If
.I \+di
is given, the integer values will be preceded by
the x and y pixel locations.
.TP
.BR \-db
Output binary byte values from 0 to 255.
.TP
.BR \-dw
Output binary 16-bit words from 0 to 65535.
.TP
.BR \-dW
Output binary 16-bit words from 0 to 65535, byte-swapped.
.TP
.BR \-df
Output binary float values.
.TP
.BR \-dF
Output byte-swapped binary float values.
.TP
.BR \-dd
Output binary double values.
.TP
.BR \-dD
Output byte-swapped binary double values.
.TP
.BR \-R
Reverse ordering of colors so that the output is blue then green
then red.
The default ordering (specified with
.I \+R)
is red then green then blue.
.TP
.BR \-n
The RGB values are non-interleaved, meaning that all the red, green
and blue data are stored together in separate chunks.
Interleaving may be turned on with the
.I \+n
option, which is the default.
.TP
.BR \-b
Print brightness values rather than RGB.
Specifying
.I \+b
turns this option off, which is the default.
.TP
.BI \-p P
Put out only the primary
.I P,
where
.I P
is one of upper or lower case 'R', 'G' or 'B' for red, green or
blue, respectively.
This option may be used to separate the Radiance primaries into
three files with three separate runs of
.I pvalue,
or only one file when only one primary is needed.
Note that there is no space between this option and its argument.
.TP
.BR \-r
Perform reverse conversion.
Input is in the format given by the other options.
The x and y resolution must be specified on the command line, unless
the image file contains a Radiance resolution string at the
beginning (see 
.I \-H
option above and
.I \-y
option below).
Specifying
.I \+r
converts from a Radiance picture to other values, which is the
default.
.TP
.BI \-p " xr yr xg yg xb yb xw yw"
On reverse conversion, RGB input uses the given set of color primaries.
These are written into the output header with the PRIMARIES variable.
.TP
.BR \-pXYZ
On reverse conversion, input is in CIE XYZ coordinates, rather than RGB.
The Y channel is assumed to be in candelas/meter^2.
.TP
.BI -y \ res
Set the output y resolution to
.I res.
If
.I \+y
is specified, then the scanlines are assumed to be in
increasing order (ie. bottom to top).
The default value for this option is 0, which means
that the picture size and scanline order must appear
as the first line after the header (if any) in the
input file.
Either an upper or lower case 'Y' may be used for this option.
Since Radiance files always contain such a line, 
this option has no effect for forward conversions.
.TP
.BI +x \ res
Set the output x resolution to
.I res.
If
.I \-x
is specified, then the scanlines are assumed to be in
decreasing order (ie. right to left).
The ordering of the
.I \-y
and
.I \+x
options determines whether the scanlines are sorted along
x or along y.
Most Radiance pictures are sorted top to bottom, then left
to right.
This corresponds to a specification of the form "\-y yres +x xres".
Either an upper or lower case 'X' may be used for this option.
Like the
.I \-y
option,
.I \-x
options have no effect for forward conversions.
.SH EXAMPLE
To look at the original, unique pixels in picture:
.IP "" .2i
pvalue \-o \-u picture | more
.PP
To convert from a 512x400 8-bit greyscale image in bottom to top,
left to right scanline ordering:
.IP "" .2i
pvalue \-r \-db \-b \-h +y 400 +x 512 input.im > flipped.hdr
.br
pflip \-v flipped.hdr > final.hdr
.SH AUTHOR
Greg Ward
.SH BUGS
Input pixel locations are ignored during a reverse
conversion, so this information is not used in determining
the scanline ordering or picture size.
.SH "SEE ALSO"
getinfo(1), pcompos(1), pfilt(1), pflip(1),
protate(1), ra_xyze(1), rpict(1), rtrace(1), rvu(1)
Revision:	1.11
Committed:	Thu Jul 18 14:45:59 2019 UTC (5 years, 9 months ago) by greg
Branch:	MAIN
CVS Tags:	rad5R3
Changes since 1.10:	+2 -7 lines
Log Message:	Removed note about -r not working with -u, since we repurposed it
#	Content
1	.\" RCSid "$Id: pvalue.1,v 1.10 2019/07/15 23:42:44 greg Exp $"
2	.TH PVALUE 1 1/15/99 RADIANCE
3	.SH NAME
4	pvalue - convert RADIANCE picture to/from alternate formats
5	.SH SYNOPSIS
6	.B pvalue
7	[
8	.B options
9	]
10	[
11	.B file
12	]
13	.br
14	.B "pvalue -r"
15	[
16	.B options
17	]
18	[
19	.B file1
20	[
21	.B "file2 file3"
22	]
23	]
24	.SH DESCRIPTION
25	.I Pvalue
26	converts the pixels of a RADIANCE picture to or from another format.
27	In the default mode, pixels are sent to the
28	standard output, one per line, in the following ascii format:
29
30	xpos ypos red green blue
31
32	If no
33	.I file
34	is given, the standard input is read.
35	.PP
36	The reverse conversion option
37	.I (-r)
38	may be used with a single input file or when reading from the
39	standard input, but if the second form is used with three separate
40	input files, the three primaries are presumed to be separated in
41	these files.
42	.TP 10n
43	.BR \-u
44	Print only unique values in the output, skipping runs of equal pixels.
45	For reverse conversions, the
46	.I \-u
47	option writes uncompressed output rather than the standard run-length RGBE
48	encoding.
49	Specifying
50	.I \+u
51	turns this option off, which is the default.
52	.TP
53	.BR \-o
54	Print original values, before exposure compensation.
55	If the input file is in XYZE format, the Y (green) channel
56	will correspond to units of candelas/meter^2.
57	Otherwise, the RGB values should be in spectral watts/steradian/meter^2.
58	Specifying
59	.I \+o
60	uses final exposed values, which is the default.
61	.TP
62	.BR \-h
63	Do not print header.
64	Specifying
65	.I \+h
66	causes the header to be printed, which is the default.
67	.TP
68	.BI \-H
69	Do not print the resolution string.
70	(See also the
71	.I \-r
72	option below.)
73	Specifying an input resolution for reverse conversion also turns
74	this option off.
75	Specifying
76	.I \+H
77	causes the resolution string to be printed, which is the default.
78	.TP
79	.BI \-s \ nbytes
80	Skip the specified number of bytes on the input header.
81	This option is useful for skipping unintelligible headers in
82	foreign file formats.
83	.TP
84	.BI \-e \ exposure
85	Adjust the exposure by the amount specified.
86	If the exposure is being given as a conversion factor, use
87	.I \+e
88	instead, so an EXPOSURE line will not be recorded in the header
89	(if any).
90	.TP
91	.BI \-g \ gamma
92	Set gamma correction for conversion.
93	When converting from a RADIANCE picture to another format,
94	the inverse gamma is applied to correct for monitor response.
95	When converting to a RADIANCE picture
96	.I (\-r
97	option), the gamma is applied directly to recover the linear values.
98	By default,
99	.I gamma
100	is set to 1.0, meaning no gamma correction is performed.
101	.TP
102	.BR \-d
103	Data only,
104	do not print x and y pixel position.
105	.TP
106	.BR \-da
107	Same as
108	.I \-d.
109	.TP
110	.BR \-di
111	Print ascii integer values from 0 to 255+.
112	If
113	.I \+di
114	is given, the integer values will be preceded by
115	the x and y pixel locations.
116	.TP
117	.BR \-db
118	Output binary byte values from 0 to 255.
119	.TP
120	.BR \-dw
121	Output binary 16-bit words from 0 to 65535.
122	.TP
123	.BR \-dW
124	Output binary 16-bit words from 0 to 65535, byte-swapped.
125	.TP
126	.BR \-df
127	Output binary float values.
128	.TP
129	.BR \-dF
130	Output byte-swapped binary float values.
131	.TP
132	.BR \-dd
133	Output binary double values.
134	.TP
135	.BR \-dD
136	Output byte-swapped binary double values.
137	.TP
138	.BR \-R
139	Reverse ordering of colors so that the output is blue then green
140	then red.
141	The default ordering (specified with
142	.I \+R)
143	is red then green then blue.
144	.TP
145	.BR \-n
146	The RGB values are non-interleaved, meaning that all the red, green
147	and blue data are stored together in separate chunks.
148	Interleaving may be turned on with the
149	.I \+n
150	option, which is the default.
151	.TP
152	.BR \-b
153	Print brightness values rather than RGB.
154	Specifying
155	.I \+b
156	turns this option off, which is the default.
157	.TP
158	.BI \-p P
159	Put out only the primary
160	.I P,
161	where
162	.I P
163	is one of upper or lower case 'R', 'G' or 'B' for red, green or
164	blue, respectively.
165	This option may be used to separate the Radiance primaries into
166	three files with three separate runs of
167	.I pvalue,
168	or only one file when only one primary is needed.
169	Note that there is no space between this option and its argument.
170	.TP
171	.BR \-r
172	Perform reverse conversion.
173	Input is in the format given by the other options.
174	The x and y resolution must be specified on the command line, unless
175	the image file contains a Radiance resolution string at the
176	beginning (see
177	.I \-H
178	option above and
179	.I \-y
180	option below).
181	Specifying
182	.I \+r
183	converts from a Radiance picture to other values, which is the
184	default.
185	.TP
186	.BI \-p " xr yr xg yg xb yb xw yw"
187	On reverse conversion, RGB input uses the given set of color primaries.
188	These are written into the output header with the PRIMARIES variable.
189	.TP
190	.BR \-pXYZ
191	On reverse conversion, input is in CIE XYZ coordinates, rather than RGB.
192	The Y channel is assumed to be in candelas/meter^2.
193	.TP
194	.BI -y \ res
195	Set the output y resolution to
196	.I res.
197	If
198	.I \+y
199	is specified, then the scanlines are assumed to be in
200	increasing order (ie. bottom to top).
201	The default value for this option is 0, which means
202	that the picture size and scanline order must appear
203	as the first line after the header (if any) in the
204	input file.
205	Either an upper or lower case 'Y' may be used for this option.
206	Since Radiance files always contain such a line,
207	this option has no effect for forward conversions.
208	.TP
209	.BI +x \ res
210	Set the output x resolution to
211	.I res.
212	If
213	.I \-x
214	is specified, then the scanlines are assumed to be in
215	decreasing order (ie. right to left).
216	The ordering of the
217	.I \-y
218	and
219	.I \+x
220	options determines whether the scanlines are sorted along
221	x or along y.
222	Most Radiance pictures are sorted top to bottom, then left
223	to right.
224	This corresponds to a specification of the form "\-y yres +x xres".
225	Either an upper or lower case 'X' may be used for this option.
226	Like the
227	.I \-y
228	option,
229	.I \-x
230	options have no effect for forward conversions.
231	.SH EXAMPLE
232	To look at the original, unique pixels in picture:
233	.IP "" .2i
234	pvalue \-o \-u picture \| more
235	.PP
236	To convert from a 512x400 8-bit greyscale image in bottom to top,
237	left to right scanline ordering:
238	.IP "" .2i
239	pvalue \-r \-db \-b \-h +y 400 +x 512 input.im > flipped.hdr
240	.br
241	pflip \-v flipped.hdr > final.hdr
242	.SH AUTHOR
243	Greg Ward
244	.SH BUGS
245	Input pixel locations are ignored during a reverse
246	conversion, so this information is not used in determining
247	the scanline ordering or picture size.
248	.SH "SEE ALSO"
249	getinfo(1), pcompos(1), pfilt(1), pflip(1),
250	protate(1), ra_xyze(1), rpict(1), rtrace(1), rvu(1)