few MiniMagick drafts

drafts.rb

image = MiniMagick::Image.open AttachedFile.last.path
image[:width]
image[:height]
image.auto_orient
image.resize "800x"
image.resize "x600"
image.format "gif"
c.rotate "-90>"
c.gravity "center"
c.compose "Over" # OverCompositeOp
c.geometry "+20+20" # copy second_image onto first_image from (20, 20)
image[:width]               # will get the width (you can also use :height and :format)
image["EXIF:BitsPerSample"] # It also can get all the EXIF tags
image["%m:%f %wx%h"] 
image.trim

def resize_and_crop_image(img, w, h)

    img_w = img[:width].to_f
    img_h = img[:height].to_f

    logger.debug "image w #{img_w} image h #{img_h}"

    #scale image to correct size
    w_ratio =  w / img_w
    h_ratio =  h / img_h

    logger.debug "w ratio #{w_ratio} h ratio #{h_ratio}"

    scale = 1

    if (img_h > h && img_w > w)
    scale = h_ratio > w_ratio ? h_ratio : w_ratio
    else
    scale = h_ratio < w_ratio ? h_ratio : w_ratio
    end

    logger.debug "scale to #{scale * 100}%"
    img.scale "#{scale * 100}%"

    img_w = img[:width].to_f
    img_h = img[:height].to_f
    logger.debug "image w #{img_w} image h #{img_h}"

    y_shift = ((img_h - h) / 2).abs
    x_shift = ((img_w - w) / 2).abs
  
    logger.debug "x shift #{x_shift} y shift #{y_shift}"

    img.crop "#{w}x#{h}+#{x_shift}+#{y_shift}"
    #img.resize "#{w}x#{h}"

    img

  end

def update_attributes(att)
 
  scaled_img = Magick::ImageList.new(self.photo.path)
  orig_img = Magick::ImageList.new(self.photo.path(:original))
  scale = orig_img.columns.to_f / scaled_img.columns
 
  args = [ att[:x1], att[:y1], att[:width], att[:height] ]
  args = args.collect { |a| a.to_i * scale }
 
  orig_img.crop!(*args)
  orig_img.write(self.photo.path(:original))
 
  self.photo.reprocess!
  self.save
 
  super(att)
end


# DELAYED processes
def process_image    
  # job = DelayedImageProcessor.new(self)
  # Delayed::Job.enqueue job
  attached_file = self

  log "JOb start"
  sleep 10

  image = MiniMagick::Image.open(attached_file.path)
  image.resize "100x100!"
  image.write attached_file.styled_path(:preview)

  log "AttachedId", attached_file.id

  AttachedFile.update(attached_file.id, processing: :finished)

  log "JOb finished"
end

handle_asynchronously :process_image, run_at: Proc.new { 5.seconds.from_now }