Dear Group,
I'm trying to display a series of Radiance renderings as a time lapse
animation.
I convert (pfilt -e +0 -r .6 -x /2 -y /2 filtered) hdr-images via
ra_tiff and the resulting tifs are combined into an animated gif via
(ImageMagick's) convert -delay 200 -quality 100 *.tif time-lapse.gif.
Each image represents a view of an atrium 1 hour apart.
The indirectly lit walls of the room that contains my view point get
displayed darker as the atrium scene brightens up.
In absolute terms one wall has a luminance of 15 cd/m2 at 9:00. That
same wall is 29 cd/m2 at 12:00, yet when displayed (using ximage) it
appears darker.
Exposure times in the headers are of course quite different:
vp-A-092108.00.pic:EXPOSURE=3.008155e+00
vp-A-092112.00.pic:EXPOSURE=3.957302e-01
Basically I want the tone mapping according to a constant (perhaps log)
scale for all images.
How can that be accomplished?
(Looks like falsecolor could do this if it also had a greyscale palette.)
Best regards,
Wouter
You can use the -e option in pfilt to adjust by a constant. Instead of using +0, you can use a value without the + symbol that is a fraction of the EXPOSURE value in your header file. -Chris
···
On 10/3/15 8:21 AM, ascendilex | Wouter Beck wrote:
Dear Group,
I'm trying to display a series of Radiance renderings as a time lapse
animation.
I convert (pfilt -e +0 -r .6 -x /2 -y /2 filtered) hdr-images via
ra_tiff and the resulting tifs are combined into an animated gif via
(ImageMagick's) convert -delay 200 -quality 100 *.tif time-lapse.gif.
Each image represents a view of an atrium 1 hour apart.
The indirectly lit walls of the room that contains my view point get
displayed darker as the atrium scene brightens up.
In absolute terms one wall has a luminance of 15 cd/m2 at 9:00. That
same wall is 29 cd/m2 at 12:00, yet when displayed (using ximage) it
appears darker.
Exposure times in the headers are of course quite different:
vp-A-092108.00.pic:EXPOSURE=3.008155e+00
vp-A-092112.00.pic:EXPOSURE=3.957302e-01
Basically I want the tone mapping according to a constant (perhaps log)
scale for all images.
How can that be accomplished?
(Looks like falsecolor could do this if it also had a greyscale palette.)
Best regards,
Wouter
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
Another option for you Wouter would be to use the phisto shell script
(assuming you're running Radiance on Mac or Linux). From the man page:
"The primary function of this script is to precompute histograms for the
pcond(1) program, which may then be used to compute multiple,
identical
exposures. This is especially useful for animations and image
compar-
isons."
This is pretty much right up your alley, for animations. As this method
uses tonemapping, you must remain mindful of what it is that you are really
displaying. Perhaps the best method is to show, side-by-side, a tonemapped
image alongside a quantitative falcesolor image of the real values.
···
On Sat, Oct 3, 2015 at 6:45 AM, Chris Kallie <[email protected]> wrote:
You can use the -e option in pfilt to adjust by a constant. Instead of
using +0, you can use a value without the + symbol that is a fraction of
the EXPOSURE value in your header file. -Chris
On 10/3/15 8:21 AM, ascendilex | Wouter Beck wrote:
Dear Group,
I'm trying to display a series of Radiance renderings as a time lapse
animation.
I convert (pfilt -e +0 -r .6 -x /2 -y /2 filtered) hdr-images via
ra_tiff and the resulting tifs are combined into an animated gif via
(ImageMagick's) convert -delay 200 -quality 100 *.tif time-lapse.gif.
Each image represents a view of an atrium 1 hour apart.
The indirectly lit walls of the room that contains my view point get
displayed darker as the atrium scene brightens up.
In absolute terms one wall has a luminance of 15 cd/m2 at 9:00. That
same wall is 29 cd/m2 at 12:00, yet when displayed (using ximage) it
appears darker.
Exposure times in the headers are of course quite different:
vp-A-092108.00.pic:EXPOSURE=3.008155e+00
vp-A-092112.00.pic:EXPOSURE=3.957302e-01
Basically I want the tone mapping according to a constant (perhaps log)
scale for all images.
How can that be accomplished?
(Looks like falsecolor could do this if it also had a greyscale palette.)
Best regards,
Wouter
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
You could also use phisto to create a luminance histogram from all your
images and tone map your images using pcond with the all image histogram as
input.
phisto frame*.hdr > allframes.hist
pcond frame0001.hdr < allframes.hist | ra_tiff - frame0001.tif
When there's a wide range of illumination conditions I find that pcond with
the histogram works best to preserve visibility and maintain consistency
between frames.
Andy
···
On Sat, Oct 3, 2015 at 5:45 AM, Chris Kallie <[email protected]> wrote:
You can use the -e option in pfilt to adjust by a constant. Instead of
using +0, you can use a value without the + symbol that is a fraction of
the EXPOSURE value in your header file. -Chris
On 10/3/15 8:21 AM, ascendilex | Wouter Beck wrote:
Dear Group,
I'm trying to display a series of Radiance renderings as a time lapse
animation.
I convert (pfilt -e +0 -r .6 -x /2 -y /2 filtered) hdr-images via
ra_tiff and the resulting tifs are combined into an animated gif via
(ImageMagick's) convert -delay 200 -quality 100 *.tif time-lapse.gif.
Each image represents a view of an atrium 1 hour apart.
The indirectly lit walls of the room that contains my view point get
displayed darker as the atrium scene brightens up.
In absolute terms one wall has a luminance of 15 cd/m2 at 9:00. That
same wall is 29 cd/m2 at 12:00, yet when displayed (using ximage) it
appears darker.
Exposure times in the headers are of course quite different:
vp-A-092108.00.pic:EXPOSURE=3.008155e+00
vp-A-092112.00.pic:EXPOSURE=3.957302e-01
Basically I want the tone mapping according to a constant (perhaps log)
scale for all images.
How can that be accomplished?
(Looks like falsecolor could do this if it also had a greyscale palette.)
Best regards,
Wouter
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
Andy's recommendation would also be mine, but you need the "-I" option to pcond to get it to read the histogram from stdin.
Cheers,
-Greg
···
From: Andy McNeil <[email protected]>
Subject: Re: [Radiance-general] Display of time lapse at constant brightness
Date: October 3, 2015 8:08:16 AM PDT
You could also use phisto to create a luminance histogram from all your images and tone map your images using pcond with the all image histogram as input.
phisto frame*.hdr > allframes.hist
pcond frame0001.hdr < allframes.hist | ra_tiff - frame0001.tif
When there's a wide range of illumination conditions I find that pcond with the histogram works best to preserve visibility and maintain consistency between frames.
Andy
On Sat, Oct 3, 2015 at 5:45 AM, Chris Kallie <[email protected]> wrote:
You can use the -e option in pfilt to adjust by a constant. Instead of using +0, you can use a value without the + symbol that is a fraction of the EXPOSURE value in your header file. -Chris
On 10/3/15 8:21 AM, ascendilex | Wouter Beck wrote:
Dear Group,
I'm trying to display a series of Radiance renderings as a time lapse
animation.
I convert (pfilt -e +0 -r .6 -x /2 -y /2 filtered) hdr-images via
ra_tiff and the resulting tifs are combined into an animated gif via
(ImageMagick's) convert -delay 200 -quality 100 *.tif time-lapse.gif.
Each image represents a view of an atrium 1 hour apart.
The indirectly lit walls of the room that contains my view point get
displayed darker as the atrium scene brightens up.
In absolute terms one wall has a luminance of 15 cd/m2 at 9:00. That
same wall is 29 cd/m2 at 12:00, yet when displayed (using ximage) it
appears darker.
Exposure times in the headers are of course quite different:
vp-A-092108.00.pic:EXPOSURE=3.008155e+00
vp-A-092112.00.pic:EXPOSURE=3.957302e-01
Basically I want the tone mapping according to a constant (perhaps log)
scale for all images.
How can that be accomplished?
(Looks like falsecolor could do this if it also had a greyscale palette.)
Best regards,
Wouter
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
In Wouter's post, he stated "In absolute terms one wall has a luminance of 15 cd/m2 at 9:00. That
same wall is 29 cd/m2 at 12:00, yet when displayed (using ximage) it appears darker."
I would be interested to understand how the output images would remain linear using a tone-mapping algorithm.
The general issue at hand is that some people want visually pleasant results, and some need numeric accuracy in the outputs. Perhaps the best approach depends upon what the intended use of the output images is, imho. (Unless I am not understanding something about the tone-mapping algorithm.) -Chris
···
On 10/3/15 1:03 PM, Greg Ward wrote:
Andy's recommendation would also be mine, but you need the "-I" option to pcond to get it to read the histogram from stdin.
Cheers,
-Greg
*From: *Andy McNeil <[email protected] <mailto:[email protected]>>
*Subject: *Re: [Radiance-general] Display of time lapse at constant brightness
*Date: *October 3, 2015 8:08:16 AM PDT
*
You could also use phisto to create a luminance histogram from all your images and tone map your images using pcond with the all image histogram as input.
phisto frame*.hdr > allframes.hist
pcond frame0001.hdr < allframes.hist | ra_tiff - frame0001.tif
When there's a wide range of illumination conditions I find that pcond with the histogram works best to preserve visibility and maintain consistency between frames.
Andy
On Sat, Oct 3, 2015 at 5:45 AM, Chris Kallie <[email protected] >> <mailto:[email protected]>> wrote:
You can use the -e option in pfilt to adjust by a constant.
Instead of using +0, you can use a value without the + symbol
that is a fraction of the EXPOSURE value in your header file. -Chris
On 10/3/15 8:21 AM, ascendilex | Wouter Beck wrote:
Dear Group,
I'm trying to display a series of Radiance renderings as a
time lapse
animation.
I convert (pfilt -e +0 -r .6 -x /2 -y /2 filtered) hdr-images via
ra_tiff and the resulting tifs are combined into an animated
gif via
(ImageMagick's) convert -delay 200 -quality 100 *.tif
time-lapse.gif.
Each image represents a view of an atrium 1 hour apart.
The indirectly lit walls of the room that contains my view
point get
displayed darker as the atrium scene brightens up.
In absolute terms one wall has a luminance of 15 cd/m2 at
9:00. That
same wall is 29 cd/m2 at 12:00, yet when displayed (using
ximage) it
appears darker.
Exposure times in the headers are of course quite different:
vp-A-092108.00.pic:EXPOSURE=3.008155e+00
vp-A-092112.00.pic:EXPOSURE=3.957302e-01
Basically I want the tone mapping according to a constant
(perhaps log)
scale for all images.
How can that be accomplished?
(Looks like falsecolor could do this if it also had a
greyscale palette.)
Best regards,
Wouter
_______________________________________________
Radiance-general mailing list
[email protected]
<mailto:[email protected]>
http://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing list
[email protected]
<mailto:[email protected]>
http://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing list
[email protected] <mailto:[email protected]>
http://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
Somehow my reply didn't go thru the first time, but the last 'graph speaks
to this issue of tonemapped versus absolute value images...
Another option for you Wouter would be to use the phisto shell script
(assuming you're running Radiance on Mac or Linux). From the man page:
"The primary function of this script is to precompute histograms for the
pcond(1) program, which may then be used to compute multiple,
identical
exposures. This is especially useful for animations and image
compar-
isons."
This is pretty much right up your alley, for animations. As this method
uses tonemapping, you must remain mindful of what it is that you are really
displaying. Perhaps the best method is to show, side-by-side, a tonemapped
image alongside a quantitative falcesolor image of the real values.
···
On Sat, Oct 3, 2015 at 11:12 AM, Chris Kallie <[email protected]> wrote:
In Wouter's post, he stated "In absolute terms one wall has a luminance of
15 cd/m2 at 9:00. That
same wall is 29 cd/m2 at 12:00, yet when displayed (using ximage) it
appears darker."
I would be interested to understand how the output images would remain
linear using a tone-mapping algorithm.
The general issue at hand is that some people want visually pleasant
results, and some need numeric accuracy in the outputs. Perhaps the best
approach depends upon what the intended use of the output images is, imho.
(Unless I am not understanding something about the tone-mapping algorithm.)
-Chris
On 10/3/15 1:03 PM, Greg Ward wrote:
Andy's recommendation would also be mine, but you need the "-I" option to
pcond to get it to read the histogram from stdin.
Cheers,
-Greg
*From: *Andy McNeil < <[email protected]>[email protected]>
*Subject: *Re: [Radiance-general] Display of time lapse at constant
brightness
*Date: *October 3, 2015 8:08:16 AM PDT
You could also use phisto to create a luminance histogram from all your
images and tone map your images using pcond with the all image histogram as
input.
phisto frame*.hdr > allframes.hist
pcond frame0001.hdr < allframes.hist | ra_tiff - frame0001.tif
When there's a wide range of illumination conditions I find that pcond
with the histogram works best to preserve visibility and maintain
consistency between frames.
Andy
On Sat, Oct 3, 2015 at 5:45 AM, Chris Kallie <[email protected]> wrote:
You can use the -e option in pfilt to adjust by a constant. Instead of
using +0, you can use a value without the + symbol that is a fraction of
the EXPOSURE value in your header file. -Chris
On 10/3/15 8:21 AM, ascendilex | Wouter Beck wrote:
Dear Group,
I'm trying to display a series of Radiance renderings as a time lapse
animation.
I convert (pfilt -e +0 -r .6 -x /2 -y /2 filtered) hdr-images via
ra_tiff and the resulting tifs are combined into an animated gif via
(ImageMagick's) convert -delay 200 -quality 100 *.tif time-lapse.gif.
Each image represents a view of an atrium 1 hour apart.
The indirectly lit walls of the room that contains my view point get
displayed darker as the atrium scene brightens up.
In absolute terms one wall has a luminance of 15 cd/m2 at 9:00. That
same wall is 29 cd/m2 at 12:00, yet when displayed (using ximage) it
appears darker.
Exposure times in the headers are of course quite different:
vp-A-092108.00.pic:EXPOSURE=3.008155e+00
vp-A-092112.00.pic:EXPOSURE=3.957302e-01
Basically I want the tone mapping according to a constant (perhaps log)
scale for all images.
How can that be accomplished?
(Looks like falsecolor could do this if it also had a greyscale palette.)
Best regards,
Wouter
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing [email protected]://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
Just an additional note. objline does not produce the oblique view. I have
tested with the table.rad in the tutorial as well and the results is the
same.
Thanks
···
On 4 October 2015 at 01:18, Rob Guglielmetti <[email protected]> wrote:
Somehow my reply didn't go thru the first time, but the last 'graph speaks
to this issue of tonemapped versus absolute value images...
Another option for you Wouter would be to use the phisto shell script
(assuming you're running Radiance on Mac or Linux). From the man page:
"The primary function of this script is to precompute histograms for the
pcond(1) program, which may then be used to compute multiple,
identical
exposures. This is especially useful for animations and image
compar-
isons."
This is pretty much right up your alley, for animations. As this method
uses tonemapping, you must remain mindful of what it is that you are really
displaying. Perhaps the best method is to show, side-by-side, a
tonemapped image alongside a quantitative falcesolor image of the real
values.
On Sat, Oct 3, 2015 at 11:12 AM, Chris Kallie <[email protected]> wrote:
In Wouter's post, he stated "In absolute terms one wall has a luminance
of 15 cd/m2 at 9:00. That
same wall is 29 cd/m2 at 12:00, yet when displayed (using ximage) it
appears darker."
I would be interested to understand how the output images would remain
linear using a tone-mapping algorithm.
The general issue at hand is that some people want visually pleasant
results, and some need numeric accuracy in the outputs. Perhaps the best
approach depends upon what the intended use of the output images is, imho.
(Unless I am not understanding something about the tone-mapping algorithm.)
-Chris
On 10/3/15 1:03 PM, Greg Ward wrote:
Andy's recommendation would also be mine, but you need the "-I" option to
pcond to get it to read the histogram from stdin.
Cheers,
-Greg
*From: *Andy McNeil < <[email protected]>[email protected]>
*Subject: *Re: [Radiance-general] Display of time lapse at constant
brightness
*Date: *October 3, 2015 8:08:16 AM PDT
You could also use phisto to create a luminance histogram from all your
images and tone map your images using pcond with the all image histogram as
input.
phisto frame*.hdr > allframes.hist
pcond frame0001.hdr < allframes.hist | ra_tiff - frame0001.tif
When there's a wide range of illumination conditions I find that pcond
with the histogram works best to preserve visibility and maintain
consistency between frames.
Andy
On Sat, Oct 3, 2015 at 5:45 AM, Chris Kallie <[email protected]> wrote:
You can use the -e option in pfilt to adjust by a constant. Instead of
using +0, you can use a value without the + symbol that is a fraction of
the EXPOSURE value in your header file. -Chris
On 10/3/15 8:21 AM, ascendilex | Wouter Beck wrote:
Dear Group,
I'm trying to display a series of Radiance renderings as a time lapse
animation.
I convert (pfilt -e +0 -r .6 -x /2 -y /2 filtered) hdr-images via
ra_tiff and the resulting tifs are combined into an animated gif via
(ImageMagick's) convert -delay 200 -quality 100 *.tif time-lapse.gif.
Each image represents a view of an atrium 1 hour apart.
The indirectly lit walls of the room that contains my view point get
displayed darker as the atrium scene brightens up.
In absolute terms one wall has a luminance of 15 cd/m2 at 9:00. That
same wall is 29 cd/m2 at 12:00, yet when displayed (using ximage) it
appears darker.
Exposure times in the headers are of course quite different:
vp-A-092108.00.pic:EXPOSURE=3.008155e+00
vp-A-092112.00.pic:EXPOSURE=3.957302e-01
Basically I want the tone mapping according to a constant (perhaps log)
scale for all images.
How can that be accomplished?
(Looks like falsecolor could do this if it also had a greyscale
palette.)
Best regards,
Wouter
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing [email protected]://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general
_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general