class ActiveStorage::Analyzer::ImageAnalyzer

the ImageMagick system library.
This analyzer relies on the third-party MiniMagick gem. MiniMagick requires
# => { width: 4104, height: 2736 }
ActiveStorage::Analyzer::ImageAnalyzer.new(blob).metadata
Example:
If the image contains EXIF data indicating its angle is 90 or 270 degrees, its width and height are swapped for convenience.
Extracts width and height in pixels from an image blob.

def self.accept?(blob) 

def self.accept?(blob)
  blob.image?
end

def metadata 

def metadata
  read_image do |image|
    if rotated_image?(image)
      { width: image.height, height: image.width }
    else
      { width: image.width, height: image.height }
    end
  end
end

def read_image 

def read_image
  download_blob_to_tempfile do |file|
    require "mini_magick"
    image = MiniMagick::Image.new(file.path)
    if image.valid?
      yield image
    else
      logger.info "Skipping image analysis because ImageMagick doesn't support the file"
      {}
    end
  end
rescue LoadError
  logger.info "Skipping image analysis because the mini_magick gem isn't installed"
  {}
rescue MiniMagick::Error => error
  logger.error "Skipping image analysis due to an ImageMagick error: #{error.message}"
  {}
end

def rotated_image?(image) 

def rotated_image?(image)
  %w[ RightTop LeftBottom ].include?(image["%[orientation]"])
end