Why the output of "Retina Magno" changed consistently when applying retina to a single picture

asked 2015-07-13 09:03:34 -0500

Sheng Liu gravatar image

updated 2015-07-14 09:03:53 -0500

I have tried to apply retina to a single picture with default parameters. As the cycle index being increased, the output of "Retina Magno" changed consistently and at last the output was a black image. I want to know why that happens. So I read the article "Using Human Visual System modeling for bio-inspired low level image processing" and find this image.

But the question still puzzle me. Could you give me some directions?

my second question: Please look at this picture.

OPL transfer function is shown in Fig4b. With the time goes by, I think the frequency tend to zero. And I think the FOPL is similar with the parvo output according to Fig11a. But the magno output not the parvo output become zero in the end! Could you tell me where the problems are? Maybe I misunderstood the author's intentions.

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Comments

what do you mean: cycle index ? (is there any code ?)

imho, picture b shows an input on the left side(with a cyclic grayscale ramp) and the parvo output img on the right

berak gravatar imageberak ( 2015-07-14 04:15:16 -0500 )edit

Thanks for your reply´╝ü

Sheng Liu gravatar imageSheng Liu ( 2015-07-14 07:55:18 -0500 )edit

was it about the image above ? (i wasn't sure)

berak gravatar imageberak ( 2015-07-14 08:04:37 -0500 )edit

The code is as follows.

 inputFrame = cv::imread("F:/changed/13.png");
        myRetina->setup("RetinaDefaultParameters.xml");
        for (int i=0;i<=40;i=i+1)
        {
            // run retina filter
            myRetina->run(inputFrame);
            // Retrieve and display retina output
            myRetina->getParvo(retinaOutput_parvo);
            //myRetina->getMagno(retinaOutput_magno);
            cv::imshow("retina input", inputFrame);
            cv::imshow("Retina Parvo", retinaOutput_parvo);
            //cv::imshow("Retina Magno", retinaOutput_magno);
            cv::waitKey(10);
        }

With the cycle index being increased, the output of "Retina Magno" changed consistently and at last the output was a black image.

Sheng Liu gravatar imageSheng Liu ( 2015-07-14 08:06:38 -0500 )edit

so, completely different, from what i thought ;)

well i tried, and i can side your findings more or less..

(well, it gets darker here, but not totally black)

it's one of those things, where you probably might want to ask the author for an explanation ?)

berak gravatar imageberak ( 2015-07-14 08:12:32 -0500 )edit

I just try to apply the retina to a single image.

Sheng Liu gravatar imageSheng Liu ( 2015-07-14 08:14:09 -0500 )edit

The image I tested is a tank model that is on the desk. In the fifth loop, there is only a tank in the retinaOutput_magno. However, in the tenth loop, both the tank and the background appear in the retinaOutput_magno. I am intresting in the specific order in which different objects appear or disappear in the magno output. What factors affect the order?

Sheng Liu gravatar imageSheng Liu ( 2015-07-14 08:30:48 -0500 )edit

just to clarify: the parvo img stays constant, right ?

berak gravatar imageberak ( 2015-07-14 08:32:16 -0500 )edit

As I observed, the parvo img is dynamic.

Sheng Liu gravatar imageSheng Liu ( 2015-07-14 08:50:18 -0500 )edit

I added a new question ;)

Sheng Liu gravatar imageSheng Liu ( 2015-07-14 08:51:58 -0500 )edit