NAME
ranimove - render a RADIANCE animation with motion
SYNOPSIS
ranimove [ -s ][ -e ][ -w ][ -f beg,end ][ -n nprocs ][ -t sec ][ -d
jnd ] rnmfile
DESCRIPTION
Ranimove is a program for progressive animation rendering. Variables
in the given rnmfile indicate input files, output file names, and
various other controls and options.
Normally, progress reports are written to the standard output, but the
-s option tells ranimove to do its work silently. The -e option tells
ranimove to explicate all variables used for the animation, including
default values not specified in the input file, and print them on the
standard output. The -w option turns off warnings about multiply and
misassigned variables and non-fatal rendering problems.
Normally, ranimove will produce one animation frame for each view given
in the specified view file. If the -f option is specified, the
animation will resume at the given frame, and continue to the end of
the sequence, or to the second frame if one is given (separated from
the first by a comma but no space).
The -n option specifies the number of processes to use for rendering.
The default value is 1, which is appropriate for most machines that
have a single central processing unit (CPU). If you are running on a
machine with multiple CPUs, a larger value up to the number of
processors may be used to improve rendering speed, depending on the
system load.
Because ranimove renders each frame progressively, it needs some
criteria for when to proceed to the next frame in the animation. The
-t option is used to specify the maximum number of seconds to spend on
any one frame. The default value for this option is 60 seconds.
Additionally, the -d option may be used to specify a termination
threshold in just-noticeable-differences. If the error can be reduced
below this number of JNDs over the whole frame before the time
allocation is spent, ranimove will then proceed to the next frame. A
value of 2.0 JNDs is the point at which 75% of the people will notice a
difference, and this is the level usually selected for such a
termination test. There is no default value for this option, which
means that rendering will proceed until the time allocation is spent
for each frame, regardless. If -t is set to 0, ranimove will spend as
much time as it takes to reduce the visible error below the value set
by the -d option.
Ranimove renders each frame in three stages. In the first stage, a
low-quality image is rendered using one ray sample per 16 pixels. In
the second stage, pixels from the previous frame are extrapolated to
their corresponding positions in this one, based on the given camera
and object movements. A set of heuristics is applied to prevent errors
in specular highlights and shadows, avoiding some of the errors typical
with the pinterp(1) program. In the third stage, additional high-
quality samples are used to refine important regions of the image that
are judged to have visible errors. This proceeds until the stopping
criteria specified by the -t and -d options are met, when the frame is
filtered and written to the designated picture file.
The chief differences between this program and ranimate(1) are that
motion blur is computed for objects as well as camera movement, and its
progressive rendering allows better control over the tradeoff between
frame accuracy and rendering time. Fewer controls are provided for
managing the picture files produced by ranimove, and no facilities for
distributed rendering are available other than executing ranimove on
different machines using the -f option to manually partition the work.
Animation variable assignments appear one per line in rnmfile. The
name of the variable is followed by an equals sign (’=’) and its
value(s). The end of line may be escaped with a backslash (’\’),
though it is not usually necessary since additional variable values may
be given in multiple assignments. Variables that should have only one
value are given in upper case. Variables that may have multiple values
are given in lower case. Variables may be abbreviated by their first
three letters. Comments in rnmfile start with a pound sign (’#’) and
proceed to the end of line.
The animation variables, their interpretations and default values are
given below.
OCTREE The name of the base octree file, which should be generated
by the oconv(1) command using the -f option. There is no
default value for this variable. If no RIF variable is
given, the octree must be specified.
RIF This variable specifies a rad(1) input file to use as a
source of rendering options and other variable settings. If
given, ranimate will execute rad and create an options file
to control rendering parameters. Ranimate will also extract
default settings for the common variables: OCTREE,
RESOLUTION, and EXPOSURE. Following the file name,
overriding variable settings may be given, which will be
passed to rad on the command line. Settings with spaces in
them should be enclosed in quotes. The execution of rad will
also update the contents of the octree, if necessary. There
is no default value for this variable.
move This variable specifies an object (or objects) with a
specific motion and/or rendering priority. Four value
arguments are expected for each appearance of this variable.
The first is the name of a parent move object, or "void" if
none. If given, the object’s transformation will be
prepended to that of its parent. The second argument is the
name of this object, which will be used to name surfaces it
contains, and as a modifier for any child objects that
reference it. The third argument is the transformation
string or file for this object. If this argument is enclosed
in quotes and begins with a hyphen (’-’), then it will be
interpreted as a static transform specification a la
xform(1). Otherwise, the argument will be taken as the name
of a file that contains one such transform specification per
line, corresponding to frames in the animation. A period
(’.’) may be given if no object transformation is desired.
The fourth argument is the name of a RADIANCE scene file (or
files) to be given to xform for transformation. If this
argument begins with an exclamation point (’!’), then it will
be interpreted as a command rather than a file. A final word
corresponding to the frame number will be appended to the
command, and its output will be passed to the input of xform
for each frame. An optinal fifth argument specifies the
rendering priority for this object. Values greater than 1
will result in preferential rendering of this object over
other portions of the image when it appears in a frame.
Values less than 1 will cause the rendering to neglect this
object in favor of other parts of the image. A value of 3.0
can be interpreted as saying the viewer is three times more
likely to look at this object than the background. A file
may be given rather than a floating point value, and this
file must contain one floating point number per line,
corresponding to frames in the animation.
VIEWFILE This variable names a file from which ranimove may extract
the view for each frame in the animation. This file should
contain one valid view per frame, starting with frame 1 on
line 1. An exception is made for a view file with only a
single view, which is used for every frame of the animation.
In this case, the END variable must also be specified. This
variable is required, and there is no default value.
END The final frame number in the animation. The default value
is computed from the number of views in the given VIEWFILE.
Normally, this variable will only be given if the view is
static.
EXPOSURE This variable tells ranimate how to adjust the exposure for
each frame. As in pfilt, the exposure setting may be given
either as a multiplier or as a number of f-stop adjustments
(eg. +2 or -1.5). Alternatively, a file name may be given,
which ranimate will interpret as having one exposure value
per line per frame, beginning with frame 1 at line 1. (See
also the VIEWFILE variable, above.) There is no default
value for this variable. If it is not given, no exposure
adjustments will be made.
BASENAME The base output file name for the final frames. This string
should contain a printf(3) style integer field to distinguish
one frame number from another. The final frames will use
this name with a ".hdr" suffix. The default value is
"frame%03d".
MBLUR This variable specifies the fraction of a frame time that the
shutter is simulated as being open for motion blur. Motion
blur is computed by ranimove using image-based rendering
methods, and will not be exact. The default value is 0,
meaning no motion blurring.
RATE This variable specifies the animation frame rate, in frames
per second. This is needed to compute the animation error
visibility. The default value is 8.
RESOLUTION
This variable specifies the desired final picture resolution.
If only a single number is given, this value will be used for
both the horizontal and vertical picture dimensions. If two
numbers are given, the first is the horizontal resolution and
the second is the vertical resolution. If three numbers are
given, the third is taken as the pixel aspect ratio for the
final picture (a real value). If the pixel aspect ratio is
zero, the exact dimensions given will be those produced.
Otherwise, they will be used as a frame in which the final
image must fit. The default value for this variable is 640.
lowq This variable may be used to specify rendering options for
the initial, low-quality ray samples. It may be given either
as a list of rendering parameter settings, or as variable
settings for the rad command, in which case the RIF variable
must also be specified.
highq This variable may be used to specify rendering options for
the final, high-quality ray samples. It may be given either
as a list of rendering parameter settings, or as variable
settings for the rad command, in which case the RIF variable
must also be specified.
oconv This variable may be used to specify special options for
oconv. See the oconv(1) manual page for a list of valid
options. (The -f option is specified by default.)
EXAMPLES
A minimal input file for ranimove might look like this:
::::::::::
sample.rnm
::::::::::
# The rad input file for our static scene:
RIF= tutor.rif
# The view file containing one view per frame:
VIEWFILE= anim1.vf
# Our central character and its motion:
move= void myguy myguy.xf myguy.rad 2.0
Note that most of the variables are not set in this file. If we only
want to see what default values ranimove would use without actually
executing anything, we can invoke it thus:
ranimove -n 0 -e sample.rnm
This will print the variables we have given as well as default values
ranimove has assigned for us.
Usually, we execute ranimove in the background, redirecting the
standard output and standard error to a file:
ranimove sample.rnm >& sample.err &
If we decide that the default values ranimove has chosen for our
variables are not all appropriate, we can add some more assignments to
the file:
RES= 1024 # shoot for 1024x resolution
MBLUR= .25 # apply camera motion blur
RATE= 15 # 15 frames/second
EXP= anim1.exp # adjust exposure according to file
lowq= QUAL=Low # low quality ray sampling
highq= QUAL=Med # high quality ray sampling
Note the use of abbreviation for variable names.
AUTHOR
Greg Ward
SEE ALSO
fieldcomb(1), oconv(1), pfilt(1), pinterp(1), rad(1), ran2tiff(1),
ranimate(1), rpict(1), xform(1)