Computer Vision project 1

Featuring Detecting and Matching

Changhung Lai, cl822

 

Customer Descriptor Design

The descriptor is composed by a 5 by 5 window with the pixel intensity and gradient. Idea is to implement a more accurate descriptor than simple descriptor but not as complicate as MOPS descriptor. A window simply record the pixel value is a good descriptor to shift feature. Besides, the gradient gives us some information on how the image pixel intensity changes on average. By the experiments result i have, this descriptor actually works better than simple descriptor but worst then MOPS of most of the time.

 

Experiments Result Comparison

 

Simple

+

SSD

Simple

+

ratio

MOPS

+

SSD

MOPS

+

Ratio

Custom

+

SSD

Custom

+

Ratio

graf

.449

.530

.394

.464

.442

.534

Leuven

.096

.538

.112

.467

.076

.512

bikes

.317

.499

.432

.534

.331

.513

wall

.212

.532

.389

.499

.289

.563

 

Harris Image

 

 

AUC plot

 

                                        (Yosemeti)                                                                                                                                       (graf)

Strength & Weaknesses

Our descriptor is variant to rotation, scale and illumination. Besides, it use three times of memory than simple descriptor. The strength is that it is a simple and straight forward descriptor but works better than simple descriptor.

       

Some Extra Test

We will test on an image with shift feature

Original image

  

 

Harris Image