Results 1 to 12 of 12

Thread: How to avoid this?

  1. #1
    Member
    Join Date
    Feb 2002
    Location
    "You Are Here"
    Posts
    276

    Default How to avoid this?



    Notice the stairs.... when the pic was resized all the moire or whatever it is comes out... it happens whether i sharpen the picture or not. How to avoid this effect?

  2. #2
    Senior Member
    Join Date
    Feb 2003
    Location
    Outside the Dry Box.
    Posts
    16,268

    Default

    abit of beginner talk.. take a bigger pic, to capture the durian den cut away the stairs to become a panorama shot?
    Logging Off. "You have 2,631 messages stored, of a total 400 allowed." don't PM me.

  3. #3

    Default

    Stick to 1/2,1/4,1/8 (50%, 25%, 12.5%) resizing ratios and see if it helps.

  4. #4
    Member
    Join Date
    Feb 2002
    Location
    "You Are Here"
    Posts
    276

    Default

    yes the "even" ratios help but then the pic either ends up too small or too big.. the source only 2.1MP.. thanks for suggestions anyway

  5. #5

    Default

    try resizing with Photoshop.

  6. #6

    Default

    This is something that i doubt you could make it go way. It is called "moire effect". it is the CCD's ability to resolve lines, whether it be close to each other, or curves, where you may see "jaggies" on the curves. Some CCDs can resolve this very well, as to keep the lines clear, sharp and distinct. But if you blow up this picture, you will see less of this effect.

  7. #7
    Member
    Join Date
    Feb 2002
    Location
    "You Are Here"
    Posts
    276

    Default

    1) already used photoshop.
    2) the moire is not there in the original....

    anyway the "even" resizing ratios have the most effect..

  8. #8

    Default

    Originally posted by fruitybix
    This is something that i doubt you could make it go way. It is called "moire effect". it is the CCD's ability to resolve lines, whether it be close to each other, or curves, where you may see "jaggies" on the curves. Some CCDs can resolve this very well, as to keep the lines clear, sharp and distinct. But if you blow up this picture, you will see less of this effect.
    Actually what he is trying to resolve is aliasing and not moire.

    Moire are interference patterns occuring in high frequency picture elements(high resolution).

    What he has is aliasing or stair-stepping which is caused by insufficient pixel resolution to represent a angled line properly. Odd or fractional resizing ratios will exaggerate the problem, while even ratios will keep it to a bare minimum.

    The only way to reduce it is to use some resampling algorithm which applies some for of filtering or smoothening algorithm(bicubic is one, perhaps you can try Genuine Fractals or B-spline), perhaps at the expense of some details.

    Think of Anti-aliasing for 3D games and you should get the idea.

  9. #9

    Default

    try resizing in many small steps instead of one big step

  10. #10

    Default

    Originally posted by mylau
    try resizing in many small steps instead of one big step
    Worth a try.

    Record an action in Photoshop and set image size to 5% increment/decrement as many times until u reach the size you need.(Free Stair Interpolation action)

    Or you can try the Lanzcos algorithm in Irfranview.

  11. #11

    Default

    thanks for the info

  12. #12
    Bedpan
    Guests

    Default

    Agree, Try Irfanview! Free Free Free

    Originally posted by Zerstorer
    Worth a try.

    Record an action in Photoshop and set image size to 5% increment/decrement as many times until u reach the size you need.(Free Stair Interpolation action)

    Or you can try the Lanzcos algorithm in Irfranview.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •