TP2: Having fun in frequences!

GIF-4105/7105 H2017

Author: Henrique Weber


The goal of this assignment is to have a better understanding of the importance of high and low frequences in an image. This will be accomplished by two practical examples: the hybrid images experiment and the blending with Laplacian Sequences. The results (obtained over my own pictures, unless otherwise noted) and a critical evaluation are shown bellow.

Part 0: Warm Up

Here the goal was to sharp a given image by adding the image details (image - gaussianBlur(image)) to itself.

Original image.
Sharpening with alpha = 5.
Original image.
Sharpening with alpha = 10.

Part 1: Hybrid Images

Hybrid image for the provided image pair.

Albert Einstein.
Marilyn Monroe.
Marilyn Einstein.
Steve Jobs (Source).
John Lennon (Source).
John Jobs.
Ferrari. (Source).
Beetle. (Source).
Margaret Thatcher (Source).
Che Guevara (Source).
Che Thatcher.

Part 1: Best Result & Supplementar Credits

The color seems to improve the results when used in the low-frequency image. Otherwise, when the scene is seen from far away (where only the low-pass frequency should be visible) the high-frequence image will still be easy to see since the colors will be enhancing the edges locations of the high-frequence image.
David Bowie (Source).
Van Gogh (Source).
Filtered image of Van Gogh.
Filtered image of David Bowie.
Van Bowie.

Part 2: Gaussian and Laplacian sequences

Sequences for the "Lincoln et Gala" image.

Gaussian Sequence.
Laplacian Sequence.

Sequences for the "Ferreetle" image.

Gaussian Sequence.
Laplacian Sequence.

Part 3: Multiresolution Mixture

In this part of the exercise we were asked to mix two images by calculating the Laplacian sequences (L_ImA(i) and L_ImB(i)) of the images and the Gaussian sequences (G_Mask(i)) of the mask. To produce the blended image, we can sum the images by the following equation: (G_Mask(i)*L_ImA(i)) + (1-G_Mask(i)*L_ImB(i)).

The Orapple = Orange + Apple

The Flying Fish = Beach + Fish

The result of this blending was acceptable although the water around the fish is not as dark as the sky.

Native Hilary = Hilary Clinton + Pocahontas

The result of blending painture and real images seems to work well. Here is one example.

Holy Ron = Ron Burgundy + Jesus

Another example of blending painture and real images, but this time inserting the paint into the real image.

Trumpkin = President Trump + pumpkin

Blending the face of a person into a fruit seems to work well too since the fruit texture (and sometimes color) is similar to human skin.

Part 3: Own pictures

Woman woman = woman + same woman

The result of this blending was by far the best one. Certainly the almost exactly background for both images helped the seamless blend.

Funny ringer = funny guy + ringer

In this case the skin and the wall color were not the same. Therefore the mixture was not perfect but still acceptable.

Part 3: Trumpkin with detailed illustration

Laplacian Sequence for President Trump.
Laplacian Sequence for pumpkin.
Gaussian Sequence for mask.