[HDRI] HDRI Digest, Vol 68, Issue 1

[Jonghoon Kim]

I appreciate your comment Axel!!

I slightly modified my code and it is working now.

However, I have one more question!

My HDR process is like below.

(Please, let me know if there is something wrong in my script.)
=====================================================

Cropping the original HDR image to match the size with the vignetting filter file
ra_xyze -r -o -u Original.hdr | pcompos -x 4368 -y 2912 - -408 -272 > Resized_for_Vignetting.hdr

Applying the vignetting filter to the cropped HDRI
pcomb -e 'ro=ri(1) / ri(2);go=gi(1) / gi(2);bo=bi(1) / bi(2)' Resized_for_Vignetting.hdr Vignetting_Filter.hdr > Vignetting_Corrected.hdr

Resizing the HDRI for glare analysis
pfilt -x 1200 -y 800 Vignetting_Corrected.hdr > Vignetting_Corrected_resized.hdr

Cropping the HDRI for glare analysis
ra_xyze -r -o -u Vignetting_Corrected_resized.hdr | pcompos -x 800 -y 800 - -200 0 > Cropped.hdr

Creating the cleaning filter
ra_tiff -r Cleaning_filter.tif Cleaning_filter.hdr

Applying the cleaning filter on the resized HDRI
pcomb Cropped.hdr -s -1000 Cleaning_filter.hdr > Final.hdr

Running the Evalglare analysis
evalglare -vta -vh 180 -vv 180 Final.hdr

=====================================================

After the process above, The header file is like below.

#?RADIANCE
CAPDATE= 2014:02:26 22:58:34
GMT= 2014:02:27 04:58:34
/Users/jonghoonkim/Desktop/Sample HDRI/Crop800_800.hdr:
CAPDATE= 2014:02:26 22:51:52
GMT= 2014:02:27 04:51:52
<stdin>:
CAPDATE= 2014:02:26 22:16:03
GMT= 2014:02:27 04:16:03
/Users/jonghoonkim/Desktop/Sample HDRI/Big_for_Vignetting.hdr:
CAPDATE= 2014:02:26 22:09:29
GMT= 2014:02:27 04:09:29
<stdin>:
CAMERA= Canon Canon EOS 60D version v.0
Photosphere created HDR image from 'Jong_-2014-0111-1104-14.jpg' 'Jong_-2014-0111-1104-17.jpg' 'Jong_-2014-0111-1104-20.jpg' 'Jong_-2014-0111-1104-22.jpg' 'Jong_-2014-0111-1104-25.jpg' 'Jong_-2014-0111-1104-28.jpg' 'Jong_-2014-0111-1104-31.jpg' 'Jong_-2014-0111-1104-34.jpg' 'Jong_-2014-0111-1104-37.jpg' 'Jong_-2014-0111-1104-40.jpg' 'Jong_-2014-0111-1104-44.jpg' 'Jong_-2014-0111-1104-48.jpg' 'Jong_-2014-0111-1104-53.jpg'
VIEW= -vtv -vh 132.979172 -vv 113.747666
CAPDATE= 2014:01:11 12:05:53
ra_xyze -r -o -u "/Users/jonghoonkim/Desktop/Sample HDRI/Big.hdr"
PRIMARIES= 0.6400 0.3300 0.2900 0.6000 0.1500 0.0600 0.3333 0.3333
pcompos -x 4368 -y 2912 - -408 -272
/Users/jonghoonkim/Desktop/Sample HDRI/Sigma_f56FishVigL.hdr:
# Output from HDRShop
EXPOSURE= 1.0000000000000
pcomb -e "ro=ri(1) / ri(2);go=gi(1) / gi(2);bo=bi(1) / bi(2)" "/Users/jonghoonkim/Desktop/Sample HDRI/Big_for_Vignetting.hdr" "/Users/jonghoonkim/Desktop/Sample HDRI/Sigma_f56FishVigL.hdr"
pfilt -x 1200 -y 800
ra_xyze -r -o -u "/Users/jonghoonkim/Desktop/Sample HDRI/Resize.hdr"
PRIMARIES= 0.6400 0.3300 0.2900 0.6000 0.1500 0.0600 0.3333 0.3333
pcompos -x 800 -y 800 - -200 0
/Users/jonghoonkim/Desktop/Sample HDRI/Cleaning_filter.hdr:
ra_tiff -r
CAPDATE= 2014:02:25 16:15:37
pcomb "/Users/jonghoonkim/Desktop/Sample HDRI/Crop800_800.hdr" -s -1000 "/Users/jonghoonkim/Desktop/Sample HDRI/Cleaning_filter.hdr"
FORMAT=32-bit_rle_rgbe


=====================================================

The header file is very long like above after the whole process.

I could run evalglare with the final.hdr. ( It looks OK until now.)

Is the header file is OK for futhur HDRI analysis?

Are there any potential error source in the head?

If I need to modify the head, can you explain a little bit more on vim and Radiance?s info?


Have a good day!

Best regards,
Jonghoon Kim

Send HDRI mailing list submissions to
hdri at radiance-online.org
To subscribe or unsubscribe via the World Wide Web, visit
http://www.radiance-online.org/mailman/listinfo/hdri
or, via email, send a message with subject or body 'help' to
hdri-request at radiance-online.org
You can reach the person managing the list at
hdri-owner at radiance-online.org
When replying, please edit your Subject line so it is more specific
than "Re: Contents of HDRI digest..."
1. Crop HDRIs in radiance and evalglare (Jonghoon Kim)
2. Re: Crop HDRIs in radiance and evalglare (Axel Jacobs)
----------------------------------------------------------------------
Message: 1
Date: Wed, 26 Feb 2014 09:33:10 -0600
From: Jonghoon Kim <jonghoon7kim at gmail.com>
To: hdri at radiance-online.org
Subject: [HDRI] Crop HDRIs in radiance and evalglare
Message-ID: <A0E6E05A-7825-41EB-AB33-B5A85BBD5625 at gmail.com>
Content-Type: text/plain; charset="us-ascii"
Dear list,
I am trying to glare analysis via HDR images captured by a canon DSLR Camera and sigma fish eye lens.
The procedure that I use was
1. Taking 13 images via gphoto2 +Crontab
2. Creating HDR images in HDRgen
3. Resize
pfilt -x 1433 -y 955 Big.hdr > resize.hdr
4.Crop & cleaning mask
ra_xyze -r -o -u resize.hdr | pcompos -x 800 -y 800 - -315 -78 > crop.hdr | pcomb -s -1000 output_masked2.hdr
5. Evalglare analysis
echo "VIEW= -vta -vh 180 -vv 180 -vp 0 0 0 -vd 1 0 0 -vu 0 0 1" > output_masked2.hdr
evalglare output_masked2.hdr
The problem is that Evalglare reports errors after the crop process.
error: no valid view specified
(There was no evalglare errors when I test it with the resized image.)
I has checked the luminance values of the HDR in photosphere and it looks OK!
Do I need to use another crop command for evalglare processing?
Please, let me know if you have any ideas.
Best regards,
Jonghoon Kim
Ph.D. student
Texas A&M University
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.radiance-online.org/pipermail/hdri/attachments/20140226/c839693a/attachment-0001.html>
------------------------------
Message: 2
Date: Wed, 26 Feb 2014 16:25:28 +0000
From: Axel Jacobs <jacobs.axel at gmail.com>
To: High Dynamic Range Imaging <hdri at radiance-online.org>
Subject: Re: [HDRI] Crop HDRIs in radiance and evalglare
<CA+dqh61Y+UOkSAzp1mE9frpGydXKLK8zJh6vPmsCaBA-9FHJzQ at mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
echo "VIEW= -vta -vh 180 -vv 180 -vp 0 0 0 -vd 1 0 0 -vu 0 0 1" >
output_masked2.hdr
is overwrite HDR image output_masked2.hdr with just the view string.
You need to edit this image in a text editor and put a full VIEW= line
back in. If you're happy using vim, then you could try Radiance's
vinfo.
Regards
Axel

Dear list,
I am trying to glare analysis via HDR images captured by a canon DSLR Camera
and sigma fish eye lens.
The procedure that I use was
1. Taking 13 images via gphoto2 +Crontab
2. Creating HDR images in HDRgen
3. Resize
pfilt -x 1433 -y 955 Big.hdr > resize.hdr
4.Crop & cleaning mask
ra_xyze -r -o -u resize.hdr | pcompos -x 800 -y 800 - -315 -78 > crop.hdr |
pcomb -s -1000 output_masked2.hdr
5. Evalglare analysis
echo "VIEW= -vta -vh 180 -vv 180 -vp 0 0 0 -vd 1 0 0 -vu 0 0 1" >
output_masked2.hdr
evalglare output_masked2.hdr
The problem is that Evalglare reports errors after the crop process.
error: no valid view specified
(There was no evalglare errors when I test it with the resized image.)
I has checked the luminance values of the HDR in photosphere and it looks
OK!
Do I need to use another crop command for evalglare processing?
Please, let me know if you have any ideas.
Best regards,
Jonghoon Kim
Ph.D. student
Texas A&M University
_______________________________________________
HDRI mailing list
HDRI at radiance-online.org
http://www.radiance-online.org/mailman/listinfo/hdri

------------------------------
_______________________________________________
HDRI mailing list
HDRI at radiance-online.org
http://www.radiance-online.org/mailman/listinfo/hdri
End of HDRI Digest, Vol 68, Issue 1
***********************************

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.radiance-online.org/pipermail/hdri/attachments/20140227/4a326f93/attachment-0001.html>

[Axel Jacobs]

Hi Kim,

Comments in-line below...

Post by Jonghoon Kim
I appreciate your comment Axel!!
I slightly modified my code and it is working now.
However, I have one more question!
My HDR process is like below.
(Please, let me know if there is something wrong in my script.)
=====================================================
Cropping the original HDR image to match the size with the vignetting filter file
ra_xyze -r -o -u Original.hdr | pcompos -x 4368 -y 2912 - -408 -272 >
Resized_for_Vignetting.hdr

You don't need the ra_xyze -r here.

If you're using a fisheye lens, then I'm not sure why the -x and -y of
pcompose are not the same. Does this have to do with your vignetting
filter?

Post by Jonghoon Kim
Applying the vignetting filter to the cropped HDRI
pcomb -e 'ro=ri(1) / ri(2);go=gi(1) / gi(2);bo=bi(1) / bi(2)'
Resized_for_Vignetting.hdr Vignetting_Filter.hdr > Vignetting_Corrected.hdr
Resizing the HDRI for glare analysis
pfilt -x 1200 -y 800 Vignetting_Corrected.hdr >
Vignetting_Corrected_resized.hdr

Deriving glare metrics from a resized HDR images gives you somewhat
different values compared to getting them off the original, larger-res
image. You might want to test this, and see how large the differences
in UGR, DGP etc are.

Post by Jonghoon Kim
Cropping the HDRI for glare analysis
ra_xyze -r -o -u Vignetting_Corrected_resized.hdr | pcompos -x 800 -y
800 - -200 0 > Cropped.hdr

Oh, so now you're cropping it into a square.

Post by Jonghoon Kim
Creating the cleaning filter
ra_tiff -r Cleaning_filter.tif Cleaning_filter.hdr

Is this cleaning filter for removing hot or dead pixels?

Post by Jonghoon Kim
Applying the cleaning filter on the resized HDRI
pcomb Cropped.hdr -s -1000 Cleaning_filter.hdr > Final.hdr
Running the Evalglare analysis
evalglare -vta -vh 180 -vv 180 Final.hdr

You can streamline this a little:

a) crop and square and make the border black:

dim=1234 # or whatever the diameter (in pixels) of the actual fisheye
on your large-size HDR
pcompos -x $dim -y $dim hdrgen.hdr -$xoffset -$yoffset \
|pcomb -e
's(x):x*x;m=if(xmax*ymax/4-s(x-xmax/2)-s(y-ymax/2),1,0);ro=m*ri(1);go=m*gi(1);bo=m*bi(1)'
\
- |pfilt > tidy.hdr

b) do some QA

By the sounds of it, you're working under LINUX. I suggest you check
out webhdrtools. This is some of the magic behind the WebHDR site,
packaged as individual Perl scripts.
http://www.jaloxa.eu/resources/hdr/webhdrtools

Before you move on to deriving the actual glare metrics, I suggest you

b1) verify that the dynamic range that you've captured within your
sequence is sufficient. Use webhdr_jpgheatmap.pl for this. If there
are any red pixels on the heatmap, the sequence is not usable for glare
stuff.

b2) verify that the recovered RSP is good. webhdr_rspplot.pl helps you
plot it (relies on gnuplot). The red, grn, and blu curve should be
almost identical, and there should be no weird wobbles. It might be
best to take a number of calibration HDRs, and to derive an averaged RSP
from them. webhdr_rspavrg.pl is your friend here.

c) fix the view

I have a tool that does this, but since it hasn't been tested properly,
I have not included it in the webhdrtools yet. You might want to give
it a try, and see if it works for you:
http://www.jaloxa.eu/pickup/webhdr_hdrcalib.pl

Run it like so:

STDVIEW="-vta -vp 0 0 0 -vd 0 1 0 -vu 0 0 1 -vv 180 -vh 180"
CF=1.0 # Your calibration factor.
# See http://www.jaloxa.eu/webhdr/calibrate.shtml
webhdr_hdrcalib.pl $STDVIEW -m $CF tidy.hdr > tidy_fixed.hdr

webhdr_hdrcalib.pl also has a -f option that will attempt to recover a
view that exists in the HDR header, but got corrupted by pcomb or
pcompos. However, for images generated by hdrgen, it's best to not do
this, since hdrgen relies on the EXIF info from the photographs that
don't always give you accurate view angles.

d) do your glare stuff...

Done. Now have a cup of tea and flick through my "Glare measurement
using HDR photography" presentation from the 2012 Radiance workshop:
http://radiance-online.org/community/workshops/2012-copenhagen

I hope you're not trying to measure glare from LED light sources...

Regards

Axel

Post by Jonghoon Kim
=====================================================
After the process above, The header file is like below.
#?RADIANCE
CAPDATE= 2014:02:26 22:58:34
GMT= 2014:02:27 04:58:34
CAPDATE= 2014:02:26 22:51:52
GMT= 2014:02:27 04:51:52
CAPDATE= 2014:02:26 22:16:03
GMT= 2014:02:27 04:16:03
CAPDATE= 2014:02:26 22:09:29
GMT= 2014:02:27 04:09:29
CAMERA= Canon Canon EOS 60D version v.0
Photosphere created HDR image from 'Jong_-2014-0111-1104-14.jpg'
'Jong_-2014-0111-1104-17.jpg' 'Jong_-2014-0111-1104-20.jpg'
'Jong_-2014-0111-1104-22.jpg' 'Jong_-2014-0111-1104-25.jpg'
'Jong_-2014-0111-1104-28.jpg' 'Jong_-2014-0111-1104-31.jpg'
'Jong_-2014-0111-1104-34.jpg' 'Jong_-2014-0111-1104-37.jpg'
'Jong_-2014-0111-1104-40.jpg' 'Jong_-2014-0111-1104-44.jpg'
'Jong_-2014-0111-1104-48.jpg' 'Jong_-2014-0111-1104-53.jpg'
VIEW= -vtv -vh 132.979172 -vv 113.747666
CAPDATE= 2014:01:11 12:05:53
ra_xyze -r -o -u "/Users/jonghoonkim/Desktop/Sample HDRI/Big.hdr"
PRIMARIES= 0.6400 0.3300 0.2900 0.6000 0.1500 0.0600 0.3333 0.3333
pcompos -x 4368 -y 2912 - -408 -272
# Output from HDRShop
EXPOSURE= 1.0000000000000
pcomb -e "ro=ri(1) / ri(2);go=gi(1) / gi(2);bo=bi(1) / bi(2)"
"/Users/jonghoonkim/Desktop/Sample HDRI/Big_for_Vignetting.hdr"
"/Users/jonghoonkim/Desktop/Sample HDRI/Sigma_f56FishVigL.hdr"
pfilt -x 1200 -y 800
ra_xyze -r -o -u "/Users/jonghoonkim/Desktop/Sample HDRI/Resize.hdr"
PRIMARIES= 0.6400 0.3300 0.2900 0.6000 0.1500 0.0600 0.3333 0.3333
pcompos -x 800 -y 800 - -200 0
ra_tiff -r
CAPDATE= 2014:02:25 16:15:37
pcomb "/Users/jonghoonkim/Desktop/Sample HDRI/Crop800_800.hdr" -s -1000
"/Users/jonghoonkim/Desktop/Sample HDRI/Cleaning_filter.hdr"
FORMAT=32-bit_rle_rgbe
=====================================================
The header file is very long like above after the whole process.
I could run evalglare with the final.hdr. ( It looks OK until now.)
Is the header file is OK for futhur HDRI analysis?
Are there any potential error source in the head?
If I need to modify the head, can you explain a little bit more on vim and Radiance?s info?