12
$\begingroup$

I want to rotate this image enter image description here by -50 degrees, and then fill up the black space around the rotated image enter image description here with a bluish color. I can't find any documentation/answers that suggest how to do it. (Sorry about the poor question formatting).

$\endgroup$
2
  • 1
    $\begingroup$ ImageRotate[] takes a Background option. Set it to something like ImageRotate[img, Background -> Blue]. $\endgroup$ Jun 22, 2015 at 4:02
  • 1
    $\begingroup$ You could also try Padding -> "Fixed" or Padding -> "Reversed" to repeat the pixel values of the image itself. $\endgroup$
    – user484
    Jun 22, 2015 at 4:24

2 Answers 2

21
$\begingroup$

Perhaps this will motivate others or your own much better answer. In the following imr is the rotated image and piece is a piece of texture cropped from the image. It is then placed in an image of same dimension as imr and the in-painted then used to in-paint.

id = ImageDimensions[imr];
mask = Erosion[Binarize[MorphologicalComponents[imr] // Colorize], 5];
ol = Rasterize[Overlay[{Image[Graphics[{}, ImageSize -> id]], piece}
    ]];
ip = Inpaint[ol, Binarize[ol]];
Inpaint[ImageAdd[ImageMultiply[imr, mask], ImageSubtract[ip, mask]], 
 ColorNegate@mask, Method -> "FastMarching"]

Options:

Manipulate[
 Inpaint[ImageAdd[ImageMultiply[imr, mask], ImageSubtract[ip, mask]], 
  ColorNegate@mask, Method -> method], {method,
  {"TotalVariation", "FastMarching", "NavierStokes", 
   "TextureSynthesis"}}]

enter image description here

$\endgroup$
6
  • $\begingroup$ Very nice! +1 :-) $\endgroup$
    – Mr.Wizard
    Jun 22, 2015 at 6:02
  • $\begingroup$ Could be tidied up a lot more but do not have time at present $\endgroup$
    – ubpdqn
    Jun 22, 2015 at 6:04
  • $\begingroup$ The "TextureSynthesis" setting looks to be the best for me. $\endgroup$ Jun 22, 2015 at 10:09
  • $\begingroup$ @Guesswhoitis. I did this in a rush...could Abe done better. I too like texture synthesis and could crop out extraneous if desired...:) $\endgroup$
    – ubpdqn
    Jun 22, 2015 at 10:11
  • $\begingroup$ This is a beautiful answer. $\endgroup$ Jun 22, 2015 at 11:19
14
$\begingroup$

As already commented you can use the Background option for ImageRotate.
You might use DominantColors to select a background color.

img = Import["https://i.stack.imgur.com/Qr60D.png"];

ImageRotate[img, -50 °,
 Background -> DominantColors[img, 1]]

enter image description here

$\endgroup$
1
  • $\begingroup$ thank you for introducing me to DominantColors +1 for that. :) $\endgroup$
    – ubpdqn
    Jun 22, 2015 at 5:24

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.