man/man1/pdfblur.1

.\" RCSid "$Id$"
.TH PDFBLUR 1 1/24/96 RADIANCE
.SH NAME
pdfblur - generate views for depth-of-field blurring
.SH SYNOPSIS
.B pdfblur
.B aperture
.B distance
.B nsamp
.B viewfile
.SH DESCRIPTION
.I Pdfblur
takes the given
.I viewfile
and computes
.I nsamp
views based on a focus distance of
.I distance
and an aperture diameter of
.I aperture
(both in world coordinate units).
When rendered and averaged together, these views will result in
a picture with the specified depth of field.
Either
.I pinterp(1)
or
.I rpict(1)
may be called to do the actual work.
(The given
.I viewfile
must also be passed on the command line to the chosen renderer, since
.I pdfblur
provides supplemental view specifications only.)\0
.PP
For
.I pinterp,
feed the output of
.I pdfblur
to the standard input of
.I pinterp
and apply the
.I \-B
option to blur views together.
In most cases, a single picture with z-buffer is all that is required
to get a satisfactory result, though the perfectionist may wish to
apply three pictures arranged in a triangle about the aperature, or
alternatively apply the
.I \-ff
option together with the
.I \-fr
option of
.I pinterp.
(The latter may actually work out to be faster, since rendering
three views takes three times as long as a single view, and the
.I \-fr
option will end up recomputing relatively few pixels by
comparison.)\0
.PP
To use
.I pdfblur
with
.I rpict,
apply the
.I \-S
option to indicate a rendering sequence, and set the
.I \-o
option with a formatted file name to save multiple output
pictures.
When all the renderings are finished, combine them with the
.I pcomb(1)
program, using appropriate scalefactors to achieve an average.
Note that using
.I rpict
is MUCH more expensive than using
.I pinterp,
and it is only recommended if the scene and application
absolutely demand it (e.g. there is prominent refraction that
must be modeled accurately).
.PP
For both
.I pinterp
and
.I rpict,
the computation time will be proportional to the number of views from
.I pdfblur.
We have found a
.I nsamp
setting somewhere between 5 and 10 to be adequate for most images.
Relatively larger values are appropriate for larger aperatures.
.SH EXAMPLES
To use
.I pinterp
to simulate an aperture of 0.5 inches on a lens focused at a
distance of 57 inches:
.IP "" .2i
rpict -vf myview -x 640 -y 480 -z orig.zbf scene.oct > orig.pic
.br
pdfblur 0.5 57 8 orig.pic | pinterp -B -vf orig.pic -x 640 -y 480
orig.pic orig.zbf > blurry.pic
.PP
To use
.I rpict
exclusively to do the same:
.IP "" .2i
pdfblur .5 57 5 myview | rpict -S 1 -vf myview -x 640 -y 480
-o view%d.pic scene.oct
.br
pcomb -s .2 view1.pic -s .2 view2.pic -s .2 view3.pic -s .2
view4.pic -s .2 view5.pic > blurry.pic
.SH AUTHOR
Greg Ward
.SH BUGS
This program really only works with perspective views.
.SH "SEE ALSO"
pcomb(1), pinterp(1), pmblur(1), rcalc(1), rpict(1), vwright(1)
Revision:	1.2
Committed:	Tue Dec 9 15:59:06 2003 UTC (20 years, 5 months ago) by greg
Branch:	MAIN
CVS Tags:	rad3R6, rad3R6P1
Changes since 1.1:	+1 -1 lines
Log Message:	Fixed RCSid specification
#	Content
1	.\" RCSid "$Id$"
2	.TH PDFBLUR 1 1/24/96 RADIANCE
3	.SH NAME
4	pdfblur - generate views for depth-of-field blurring
5	.SH SYNOPSIS
6	.B pdfblur
7	.B aperture
8	.B distance
9	.B nsamp
10	.B viewfile
11	.SH DESCRIPTION
12	.I Pdfblur
13	takes the given
14	.I viewfile
15	and computes
16	.I nsamp
17	views based on a focus distance of
18	.I distance
19	and an aperture diameter of
20	.I aperture
21	(both in world coordinate units).
22	When rendered and averaged together, these views will result in
23	a picture with the specified depth of field.
24	Either
25	.I pinterp(1)
26	or
27	.I rpict(1)
28	may be called to do the actual work.
29	(The given
30	.I viewfile
31	must also be passed on the command line to the chosen renderer, since
32	.I pdfblur
33	provides supplemental view specifications only.)\0
34	.PP
35	For
36	.I pinterp,
37	feed the output of
38	.I pdfblur
39	to the standard input of
40	.I pinterp
41	and apply the
42	.I \-B
43	option to blur views together.
44	In most cases, a single picture with z-buffer is all that is required
45	to get a satisfactory result, though the perfectionist may wish to
46	apply three pictures arranged in a triangle about the aperature, or
47	alternatively apply the
48	.I \-ff
49	option together with the
50	.I \-fr
51	option of
52	.I pinterp.
53	(The latter may actually work out to be faster, since rendering
54	three views takes three times as long as a single view, and the
55	.I \-fr
56	option will end up recomputing relatively few pixels by
57	comparison.)\0
58	.PP
59	To use
60	.I pdfblur
61	with
62	.I rpict,
63	apply the
64	.I \-S
65	option to indicate a rendering sequence, and set the
66	.I \-o
67	option with a formatted file name to save multiple output
68	pictures.
69	When all the renderings are finished, combine them with the
70	.I pcomb(1)
71	program, using appropriate scalefactors to achieve an average.
72	Note that using
73	.I rpict
74	is MUCH more expensive than using
75	.I pinterp,
76	and it is only recommended if the scene and application
77	absolutely demand it (e.g. there is prominent refraction that
78	must be modeled accurately).
79	.PP
80	For both
81	.I pinterp
82	and
83	.I rpict,
84	the computation time will be proportional to the number of views from
85	.I pdfblur.
86	We have found a
87	.I nsamp
88	setting somewhere between 5 and 10 to be adequate for most images.
89	Relatively larger values are appropriate for larger aperatures.
90	.SH EXAMPLES
91	To use
92	.I pinterp
93	to simulate an aperture of 0.5 inches on a lens focused at a
94	distance of 57 inches:
95	.IP "" .2i
96	rpict -vf myview -x 640 -y 480 -z orig.zbf scene.oct > orig.pic
97	.br
98	pdfblur 0.5 57 8 orig.pic \| pinterp -B -vf orig.pic -x 640 -y 480
99	orig.pic orig.zbf > blurry.pic
100	.PP
101	To use
102	.I rpict
103	exclusively to do the same:
104	.IP "" .2i
105	pdfblur .5 57 5 myview \| rpict -S 1 -vf myview -x 640 -y 480
106	-o view%d.pic scene.oct
107	.br
108	pcomb -s .2 view1.pic -s .2 view2.pic -s .2 view3.pic -s .2
109	view4.pic -s .2 view5.pic > blurry.pic
110	.SH AUTHOR
111	Greg Ward
112	.SH BUGS
113	This program really only works with perspective views.
114	.SH "SEE ALSO"
115	pcomb(1), pinterp(1), pmblur(1), rcalc(1), rpict(1), vwright(1)