PixQL: SQL for image processing

Post by kbenson » Tue, Jun 30, 2015, 4:31 PM UTC

phildo3 wrote: post #22

kbenson wrote: post #6

If you are going to use SQL select, why use a separate operate statement when you could just use SQL's method for this, update? For that matter, if you are going to use SQL syntax, I would imagine you would want to keep one of the main features, which is joining of datasets. Being able to join an image with itself in some manner (or another image...), would be really useful. Instead of globals, use the images as tabl…

Author here- My reason for deviating slightly from traditional SQL syntax is that I don't find it to be super intuitive. Yes, "UPDATE color SET r = 255 WHERE col = 100" is a pretty straightforward looking thing for those of us familiar with SQL, but simple things like the fact that you set the value before deciding what you're setting the value of are a bit off putting. The separation of queries into multiple stateme…

  # Join image to itself but offset by one pixel and report the average of the RGB values
  SELECT (img1_pixel.red+img2_pixel.red)/2
         (img1_pixel.green+img2_pixel.green/2
         (img1_pixel.blue+img2_pixel.blue)/2
  FROM   img1 img1_pixel INNER JOIN img1 img2_pixel
         ON img1_pixel.column = img2_pixel.column
         AND img1_pixel.row = img2_pixel.row+1;

  # Superimpose one image over another, offset by 100 pixels width/height
  UPDATE img1, img2
  SET    img1.rgb = img2.rgb
  WHERE  img1.row = img2.row+100
         AND img1.column = img2.column;

Post by phildo3 » Tue, Jun 30, 2015, 7:12 PM UTC

ddebernardy wrote: post #5

Does this have any practical use? It seems like the image equivalent of treating an HTML file as a huge string of characters -- instead of as the representation of a DOM tree. Which makes very little sense. Plus, you seldom want to do trivial things like selecting red pixels and flipping their color to green. You want to select red eyes and flip those to their correct color.