Module: DynamicImage::ImageProcessor::Transform

Included in:
DynamicImage::ImageProcessor
Defined in:
lib/dynamic_image/image_processor/transform.rb

Overview

ImageProcessor::Transform

Cropping, resizing and rotation. Each operation is applied to every frame of an animated image.

Instance Method Summary collapse

Instance Method Details

#crop(crop_size, crop_start) ⇒ DynamicImage::ImageProcessor

Crops the image.

Parameters:

  • crop_size (Vector2d) —

    the size of the crop

  • crop_start (Vector2d) —

    its top left corner

Returns:

Raises:



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# File 'lib/dynamic_image/image_processor/transform.rb', line 15

def crop(crop_size, crop_start)
  return self if crop_start == Vector2d(0, 0) && crop_size == size

  unless valid_crop?(crop_start, crop_size)
    raise DynamicImage::Errors::InvalidTransformation,
          "crop size is out of bounds"
  end

  each_frame do |frame|
    frame.crop(crop_start.x, crop_start.y, crop_size.x, crop_size.y)
  end
end

#resize(new_size) ⇒ DynamicImage::ImageProcessor

Resize the image to a new size. The aspect ratio is not preserved; crop first if that matters.

Parameters:

  • new_size (Vector2d) —

    the size to resize to

Returns:



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# File 'lib/dynamic_image/image_processor/transform.rb', line 32

def resize(new_size)
  new_size = Vector2d(new_size)
  apply image.thumbnail_image(new_size.x.to_i,
                              height: new_size.y.to_i,
                              crop: :none,
                              size: :both)
end

#rotate(degrees) ⇒ DynamicImage::ImageProcessor

Rotates the image. The rotation must be a multiple of 90 degrees.

Parameters:

  • degrees (Integer) —

    the angle

Returns:

Raises:



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# File 'lib/dynamic_image/image_processor/transform.rb', line 45

def rotate(degrees)
  degrees = degrees.to_i % 360
  return self if degrees.zero?

  if (degrees % 90).nonzero?
    raise DynamicImage::Errors::InvalidTransformation,
          "angle must be a multiple of 90 degrees"
  end

  each_frame { |frame| frame.rotate(degrees) }
end