The maths of art

I'm writing a feature on the mathematics behind image processing software such as Photoshop and am looking for an expert who can explain some recurring concepts in an easy to understand way.
I'll be looking at edge detection, Gaussian blur and fast Fourier transform in detail. If someone would like to give a description of how each or any filter works I would greatly appreciate it.
Thanks,
Harriet

About 2 years ago there was a long thread on the math of a photoshop correction.  Can't remember what it was now. 
Don't know if a web search will turn up anything, but using math is probably not the correct word, as that was not the subject.
Good luck

Similar Messages

  • Why does iTunes display the same album art for different songs, but from the same artist?

    Hi,
    a couple of days ago I decided I wanted all of my songs to have an album art. Before I didn't actually care, but since I discovered the view mode with the album arts at the top (the fourth one) I began searching for the right arts, since I like it this way.
    I've stumbled upon a problem though. When I add two or more songs from the same artist, iTunes chooses to assign the same album art to the songs. It chooses the album art of the song I added first to my music library. How do I get it to show the proper album art?
    I use a program called 'Mp3Tag' to change all the information of my songs. When it's just a single, I end up having an 'artist', 'title', 'genre' and 'cover'. The rest of the information doesn't bother me. With albums I add more information though.
    Here's an example:
    I added two songs, one being 'Usher - Climax (Kaskade Remix)' and the other one being 'Usher - Scream'. The one added first was 'Scream'. As you can see below, iTunes somehow assigns the same album art to both songs, while clicking on 'get info' clearly shows the songs have different album arts.
    I discovered something else though:
    When adding an 'album name' to the songs, they will show properly, as seen below. The thing is though, I don't want to add an album name. When I sync the songs to my iPod, my 'albums' list will show all of the songs as well, which I don't want.
    Is there any way to solve this another way where iTunes won't sort by album, but by song title?
    Thanks in advance.

    Can anyone please answer my question?

  • Trying to do the math... (HDD related)

    Hi,
    I am putting together a new PC for editing and was wondering, how fast a HDD really has to be?! I read all the FAQ and understand, that there are plenty of suggestions out there, on how to setup your HDD's! However, I would like to be able to do the math myself and understand, why a given setup is recommended! If I take some 4K Cin footage of my GoPro Hero 3 BE, and enter the information here:
    http://web.forret.com/tools/video_fps.asp?width=4096&height=2160&fps=15&space=rgb444&depth =10 
    (4096 x 2160, 15FPS, RGB 4:4:4 and 10 bits/color... I just picked something for demonstration purposes only) it tells me, that the Uncompressed bitrate is 497,66 MB/s.
    If I now look at a chart like this:
    http://www.tomshardware.com/charts/hdd-charts-2013/-01-Read-Throughput-Average-h2benchw-3. 16,2901.html 
    and pick a HDD, with lets say 150MB/s, what does this now mean?! The bitrate is clearly higher than the "speed" of the HDD. Does this mean, my playback is going to be jerky?! I believe so, but I am not sure what part a graphics Card plays here?! I also understand, that a slow HDD, can act as the bottle neck of a given system. So no matter how fast your CPU is, a slow HDD setup will slow the whole system down. But how fast does a HDD really have to be, so it doesn't slow the system down?! Is there some way to do the math and know in advance, what is going to work and what not?! Or is it as simple as picking a SD card for a GoPro?! If my video format delivers, lets say 500MB/s, I would need a SD card that is at LEAST this fast, so it can capture the video without dropping frames, right?! At least this is how I understand it, ha ha.
    It must work a little bit different on a PC though, since the footage doesn't have to be captured in real time, correct?! A slow HDD is now going to just increase render times, right?!
    G, I am so tired of trying to explain, what I mean, LOL. Hopefully all of this will make sense to someone out there?!
    thanks,
    KMD
    p.s. Maybe it is really as simpe as just taking the bitrate for one track, adding all tracks up and whatever number comes up, your HDD has to be at least that fast, LOL?!

    SAFEHARBOR11 wrote:
    The 8-drive RAID reference was in regards to the "4:4:4 10-bit uncompressed HD" example that you offered. I sell those drives, part of my job, that is how I know. But this does not apply to GoPro footage, the above example is very rare, stuff Hollywood-types might use and not for you or I to worry about.
    Black Magic Design has a drive speed test utility that you can run and it will tell you what video formats will work with your drive setup. There are also charts and tools out there, such as AJA Data Rate Calculator for PC or Mac, and now available from Apple App Store for iPhones - http://www.aja.com/en/software
    Please note when playing with the calculator that if the format is "8-bit" or "10-bit" that references UNCOMPRESSED video, and you are not working with that. Since the calculator doesn't list the GoPro (Cineform) codec, not sure what the data rate is going to be, but much lower for sure.
    Looking at the requirements for GoPro Studio Premium, they are recommending a 7200rpm unit, and fast connection if external, but nothing fancy so I wouldn't worry about needing any special drives.
    Thanks
    Jeff Pulera
    Safe Harbor Computers
    Jeff,
    I am planning on using 4k in the near Future, so I need to worry about it, ha ha. The other thing is, a tool that measures my drive speed is useless for me, as of right now, since I do not have a system yet! Working on putting one together as we "speak". Anyhow, you pointing out the AJA Data Rate Calculator to me, is what made me realize, that I had the answer in front of me, the whole time!
    http://web.forret.com/tools/video_fps.asp?width=4096&height=2160&fps=15&space=rgb444&depth =10
    Either AJA or this site, will help me figuring out the data rate of most video formats... I have no idea why I didn't realize that the first time?! I read my OP and I want to delete it, ha ha...
    Thanks again for all the help!
    KMD

  • "Why aren't songs with the same album art grouped together?" - Take 2

    I've done all the tricks suggested in the doc nu 304389.
    I still have some albums splitted in 2 or 3 versions with the same cover art and different songs on each version... How to regroup the rebels??

    I've found the solution:
    There is sometimes a useless blank space at the end of the name of an album.
    Edit the information: in the album field, remove an eventual blank space at the end of the name of the album by backspacing...
    Et voilà!

  • I think i got ripped off by this verizon store , I got the 4 line $140.00 edge plan, which I had to pay for the phone in monthly payment, i did the math it was 268.00 total..  At check out this guy charge me $50.00 care package for each phone and sim card

    I think i got ripped off by this verizon store , I got the 4 line $140.00 edge plan, which I had to pay for the phone in monthly payment, i did the math it was 268.00 total..  At check out this guy charge me $50.00 care package for each phone and sim card which was $10.00 , $25.00 set up with TCP and he said the rest was tax.  I had to pay $474.36.. my brother went to costco and did the same verizon deal he didn't have to pay anything...

    Welcome to this forum.
    This is a customer to customer forum only, where forum members, who are only BT customers, can help each other with BT Retail products and services.
    Anything you post here does not go to BT. Although the forum is moderated by BT, not all posts are read.
    I have asked a moderator to provide assistance, they will post an invite on this thread.
    They are the only BT employees on this forum, and are a UK based team of people, who take personal ownership of your problem.
    Once you get a reply, make sure that you are logged into the forum, then click on their name, you will see a screen like this. Click on the link as shown below.
    Please do not send them a personal message, as they may not be on duty for a long time, and your message will not be tracked properly.
    For your own security, do not post any personal details, on this forum. That includes any tracking number you are give.
    They will respond either by phone or e-mail within 5-6 working days.
    Please use the tracked e-mail, to reply, not via the forum. Thanks
    This is the form you should see when you click on the link. If you do not see this form, then you have selected the wrong link.
    When you submit the form, you will receive an enquiry number, so please keep a note of it
    There are some useful help pages here, for BT Broadband customers only, on my personal website.
    BT Broadband customers - help with broadband, WiFi, networking, e-mail and phones.

  • Windows Media Player in Windows 7 displays the same album art picture for nearly all songs!

    Hello,
    I have just installed Windows 7 Home Premium as a clean install on my PC.  I then imported all my music files back onto the PC and opened up Windows Media Player and found that probably 95% of the songs have the same album cover (Timbaland - Shock Value) against them, instead of how thety were before (either the correct album art, or no album art at all).  Does anybody have any ideas what is going on here as it is pretty annoying that nearly every song has the same album art cover.
    If anyone has any ideas I'd be very grateful.
    Thanks,
    Ian

    Hi Parkesian,
    I would like to suggest you reset the database for Windows Media Player 12 to check the issue.
    Clear the Windows Media Player database
    ========================================
    1. Close Windows Media Player.
    2. Press Win + R to open Run, copy "%LocalAppData%\Microsoft\Media Player" (without the quotation marks) to the Open box and press Enter.
    3. In the Media Player folder, delete all of the files.
    Note that it is not necessary to remove the folders that are also in this folder.
    4. Restart Windows Media Player.
    At this point Windows Media Player will automatically rebuild the database.
    What’s the result?
    Arthur Li - MSFT

  • Is it possible for the next IOS 6 update for the music album art to display on the homescreen as a backround image when music is playing?

    Is it possible for the next IOS 6 update for the music album art to display on the homescreen as a backround image when music is playing?

    It does, under certain circumstances. If you are playing music and lock the phone or it locks on its own, when you wake it up, the album art will show. It also shows as the background if you are in the music app. If this is not exactly what you are looking for, you can submit feedback to Apple about this feature at www.apple.com/feedback.

  • Does the Math.Random() work differently in Firefox and Safari??

    Hello,
    I was wondering if anyone can help me with a problem I'm
    running into using the math.random(). I'm using Flash CS3 and
    created a very simple script to select random frames in a simple
    movie. It works as expected in the CS3 environment and in Safari
    but it doesn't work correctly in Firefox or in the DotNetNuke
    module I am using. Here is the code:
    i = Math.ceil(Math.random() * 3);
    gotoAndPlay("Image"+i);
    I would appreciate any help you can provide.

    Thanks for following up with me. Yes. When I test the movie
    its works fine in Safari but not in Firefox and I don't have a clue
    as to why. I hope that you can shed some light on this for me.
    Thanks.

  • Songs with the same album art not grouped together in iTunes for Windows

    Brand new iTunes user here - do not yet have an iPod! (Needed some music only on iTunes)
    When I first started up iTunes, it imported all of my music I already had on my computer. A few of them are soundtracks with different artists.
    When they are shown in the iTunes library, the soundtracks have been broken up by Artist instead of staying as a whole album. How do I get the songs back together as one album? I found the folder on my computer where they are stored and combined them there, but they are still separate in the iTunes library.
    Thanks from a total newbie!

    Mark the tracks on the album as "Part of a compilation" and fill in the Album Artist field as "Various Artists". Click on the first track of your album to highlight it, hold down the shift key and click on the last track to highlight everything in between. Right click on the selection and choose Get Info. You'll get a message asking if you want to edit multiple items, say yes. If you are using iTunes 8 in the box that opens go to the Options tab and change "part of a compilation" to Yes and choose OK.
    Also in your library click on the title bar of album column to bring all the tracks in the same album together. If you keep clicking in the title you can choose it to sort by Album, Album by Artist or Album by Year. Clicking on the little triangle on the right side of the column header changes the sort direction. Pointing up and the column is sorted in Ascending order (A to Z). Pointing down and the column is sorted in Descending order (Z to A).
    You can also have a look at this article: Why aren't songs with the same album art grouped together

  • Where on the Mac can I find the math symbol for Pi. Ie. what is the Unicode number for Pi.?

    Where on the Mac can I find the math symbol for Pi?
    Ie. what is the Unicode number for Pi.?
    I am using system 10.6.8
    Jubbjubb.

    Jubbjubb wrote:
    Where on the Mac can I find the math symbol for Pi?
    On the US keyboard layout, alt/option + p = π

  • How do i pass a daqmx task from labview to matlab using the math interface toolkit?

    I want to use DAQMX functions from Matlab using the Math Interface Toolkit (MIT). How can I have a labview function output (return) the DAQMX task to matlab via the MIT?
    I want to do this so I can start a DAQMX task in Labview from a matlab function and return control to matlab without losing the task.

    Hi Mark,
    (I already posted this answer in your other thread, but let's keep THIS thread alive - it makes more sense here in the LabVIEW forum than in Instrument Control forum.)
    Since the DAQmx Task is not a native data type that can be passed directly to MATLAB from LAbVIEW, try flattening the DAQmx Task to a string before passing to MATLAB. However, I doubt that you can access the task from within MATLAB, but feel free to give it a try.
    Good luck!
    - Philip Courtois, Thinkbot Solutions

  • Whats the "Math" for showing FAST photos in a SLIDESHOW?.....

    Yes, I'm totally DUMB when it comes to math!...
    I"m creating a SLIDESHOW, and I'd like to show some photos VERY FAST!... I know how to do one (1) second, but I'd like to show some photos much much faster!. I don't know if its .03, 0.4, 0.5 or whatever the numbers are to show very very fast photo frames.
    Please advise.
    Thanks...

    The math is really simple:
    Use another app.
    IPhoto will not show a pic for less that 1 second.
    I strongly suspect that none of the usual Slideshow apps will either and that you're looking for a Timeline based video editor like Final Cut for that kind of close editing.
    Regards
    TD

  • Trig functions in the Math class

    One of the techniques suggested to master for the Java Programmer exam is using the trigonometry methods in the Math class. Does that mean that on the exam I would need a trigonometry knowledge or is it enough to be familiar with their signature ?

    No trig knowledge - just questions on the Java language, including method signatures. Check out the various mock exams such as at http://www.javaranch.com/certfaq.jsp

  • Trying to learn the Math.max function

    Hello,
    I am trying to figure out how to use the Math.max funtion. Here is my simple code, but it has an error.
    Anyone know what I did wrong here.
    thanks
    function myBiggie(); {
    Math.max(4:Number,19:Number);
    myBiggie();
    babs

    You're welcome.  Here's another version that makes a little more "useful" sense (not making a point, just demo-ing some things)...
    function myBiggie(num1:Number, num2:Number):Number {
         return Math.max(num1, num2);
    var biggest:Number = myBiggie(4,19);
    trace(biggest);

  • How do you delete incorrect cover art and replace it with the correct cover art?

    How do you delete incorrect cover art and replace it with the correct cover art?

    Select the song and open the "Get Info" window (Cmd + I or File > Get Info).  Select the artwork tab.  Select the artwork and click the "Delete" button.  Use the "Add" button to select the replacement art or just drag it into the window.  Click "OK" to save your changes.

Maybe you are looking for