[FRIAM] Fourier image space, duality, filtering and compression

[Stephen Guerin]

Jon, Mike and I were talking about fourier transforms on images, JPEG
compression and filtering at this morning's FRIAM.

Here's a nice site that lets you load an image, and its fourier transform
(amplitude spectrum) in cartesian or log-polar.
 https://www.djmannion.net/img_freq_web/

 A menu allows you to pull up sample images, simple sine waves in various
frequencies and orientation and a live webcam image to see their point
dualities in fourier space.

The lower panel lets you filter high and low cutoffs (much like jpeg
compression) to see the impact on the image.

links related to compression:

https://blog.demofox.org/2020/11/04/frequency-domain-image-compression-and-filtering/

https://micro.magnet.fsu.edu/primer/java/digitalimaging/processing/fouriertransform/

different but related use of fourier transform for finding epicycles in a
drawing:

   - https://www.jezzamon.com/fourier/
   - https://www.myfourierepicycles.com/


-S


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[FRIAM] Game Theory!

[glen]

https://www.youtube.com/watch?v=5NAQMoRzuxk

First laugh out loud of the week!  Yes, I know. My week has sucked.

--
ꙮ Mɥǝu ǝlǝdɥɐuʇs ɟᴉƃɥʇ' ʇɥǝ ƃɹɐss snɟɟǝɹs˙ ꙮ

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Re: [FRIAM] Advice sought: data compromise

[glen]

And consider putting a temporary lock on your credit. It should be free with any of 
the 3 big credit reporting agencies. I used equifax 
 when my 
info was leaked. The lock simply means you (or anyone impersonating you) has to jump 
through a few more hoops to get a loan or whatever.

On 8/12/22 06:53, Steve Smith wrote:

Nick -

If I understand your story correctly, I would start by verifying the "local health care company".  If they 
are someone you do business with, then you can contact them otherwise through "normal" channels (not 
website/e-mail) that you already trust (you do business with them already?)   It is not good practice for *them* to be 
directing you to a third-party "monitoring" site in they way they seem to be.   If you do NOT do business 
with them already then it is almost assuredly a phishing attempt.  Or maybe more appropriately a "phlushing" 
attempt... what predators do to try to get prey to panic and expose themselves so they can pounce and/or run you to 
ground.

Hope your summer is going well otherwise!

- Steve


On 8/12/22 4:12 AM, David Eric Smith wrote:

Yes, Nick,

Stay in your cage of distrust.  I will be very surprised if you ultimately 
determine that this _wasn’t_ a scam.  Maybe even add a bar or two to your cage 
walls: I would generally not log into a link received in an email, if there 
weren’t some way I could initiate the contact with a known company through some 
website that the various certifiers think is theirs.

Eric




On Aug 12, 2022, at 10:24 AM,  
 wrote:

Hi, everybody,
Sorry for  the bother.
A local health care company writes me to say they have compromised all my 
identity data, and offers to pay for “Kroll Monitoring Services”, giving me an 
ID number with which to log into their site.  When I do this, the site fills in 
my correct address and last name but an incorrect first name, and asks me to 
enter all my identity data.  At this point, I begin to contemplate that the 
notice itself may be a fraud.  I eventually find Kroll on the web, but it 
wasn’t all that easy.  None of the sites that evaluate credit monitoring 
services has it.  How do I extricate myself from my cage of distrust?
Nick
Nick Thompson
thompnicks...@gmail.com


--
ꙮ Mɥǝu ǝlǝdɥɐuʇs ɟᴉƃɥʇ' ʇɥǝ ƃɹɐss snɟɟǝɹs˙ ꙮ

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Re: [FRIAM] Advice sought: data compromise

[Steve Smith]

Nick -

If I understand your story correctly, I would start by verifying the 
"local health care company".  If they are someone you do business with, 
then you can contact them otherwise through "normal" channels (not 
website/e-mail) that you already trust (you do business with them 
already?)   It is not good practice for *them* to be directing you to a 
third-party "monitoring" site in they way they seem to be.   If you do 
NOT do business with them already then it is almost assuredly a phishing 
attempt.  Or maybe more appropriately a "phlushing" attempt... what 
predators do to try to get prey to panic and expose themselves so they 
can pounce and/or run you to ground.


Hope your summer is going well otherwise!

- Steve


On 8/12/22 4:12 AM, David Eric Smith wrote:

Yes, Nick,

Stay in your cage of distrust.  I will be very surprised if you 
ultimately determine that this _wasn’t_ a scam.  Maybe even add a bar 
or two to your cage walls: I would generally not log into a link 
received in an email, if there weren’t some way I could initiate the 
contact with a known company through some website that the various 
certifiers think is theirs.


Eric



On Aug 12, 2022, at 10:24 AM,  
 wrote:


Hi, everybody,
Sorry for  the bother.
A local health care company writes me to say they have compromised 
all my identity data, and offers to pay for “Kroll Monitoring 
Services”, giving me an ID number with which to log into their site.  
When I do this, the site fills in my correct address and last name 
but an incorrect first name, and asks me to enter all my identity 
data.  At this point, I begin to contemplate that the notice itself 
may be a fraud.  I eventually find Kroll on the web, but it wasn’t 
all that easy.  None of the sites that evaluate credit monitoring 
services has it.  How do I extricate myself from my cage of distrust?

Nick
Nick Thompson
thompnicks...@gmail.com
https://wordpress.clarku.edu/nthompson/ 


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