Radon Transform Based Real-Time Weed Classifier
Muhammad Inam ul Haq
1
, Abdul Muhamin Naeem
2
, Irshad Ahmad
3
, Muhammad Islam
4
1
Center of IT, Institute of Management Sciences, Peshawar.
2
Department of Computer Sciences, Farabi College Peshawar
3
Department of Computer Sciences, Islamia College Peshawar.
4
Department of Telecom Engineering, FAST-NU Peshawar.
{inamix@imsciences.edu.pk, (abdulmuhamin, iakhalil2003)@yahoo.com, m.islam@nu.edu.pk}
Abstract
A machine vision system to detect and discriminate
crop and weed plants in a commercial agricultural
environment was developed and tested. Images are
acquired in agricultural fields under natural illumination
were studied extensively, and a weed classifier based on
Radon Transform is developed. This classifier is
specifically developed to classify images into broad
(having broad leaves) and narrow (having narrow
leaves) classes for real-time selective herbicide
application. The developed system has been tested on
weeds in the lab; the results shows reliable performance
and significantly less computational efforts on images of
weeds taken under varying field conditions. The analysis
of the results shows over 93.5% classification accuracy
over a database of 200 sample images with 100 samples
from each category of weeds.
Keywords--- Ecology, Image Processing, Radon
Transform, Real-Time Recognition, Weed detection.
1. Introduction
1.1. Background
Increasing farm sustainability and protecting water
quality are two major goals of current agricultural
research. Total variable costs in 2002 for U.K were
within a range of £1,720/ha and £1,870/ha for main crop
potatoes, of which herbicides accounted for between 3%
and 4% of costs, fungicides accounted for about 8% of
variable costs and nematicides accounted for about 14%-
16% of variable costs. United States farmers applied
about $16 billion of herbicides in 2005 (The Value of
Herbicides in U.S. Crop Production: 2005 Update,
CropLife Foundation), representing a significant portion
of the variable costs of agricultural production.
Although weeds are not evenly distributed on field,
weed treatments are mostly applied with the same dose
over the entire field, while the herbicides are used more
efficiently by adjusting the herbicide dose to specific
weed [10].
In order to perform a localized weed treatment, local
weed population must be evaluated on the field. Only
automatic weed detection can be economically justified
[7, 8].
Species based identification of weeds is not
necessary for its precise treatment. All weeds with the
same treatment can be placed in one class, but this might
create classes with high variance in spectral response,
because weeds might have very different optical
characteristics. A well considered choice of weed
categories should be based on treatment and
morphological properties of weeds. Classification into
narrow and broad leaves seems particularly interesting
because these weed groups are treated with different
herbicides and have different optical characteristics [11].
The treatment of weeds, i.e. use herbicides, only where it
is needed and not on the whole field, will be a great
environmental and economical benefit.
1.2. Related Work
Much research has investigated strategies to control
weeds with less herbicide to reduce production costs and
to protect the environment.
A verity of visual characteristics that have been used
in plant identification can be divided into three
categories: Spectral Reflectance, Morphology and
Texture. The photosensor-based plant detection systems
[2] can detect all the green plants and spray only the
plants. A machine-vision guided precision band sprayer
for small-plant foliar spraying [3] demonstrated a target
deposition efficiency of 2.6 to 3.6 times that of a
conventional sprayer, and the non-target deposition was
reduced by 72% to 99%.
A system that could make use of the spatial
distribution information in real-time and apply only the
necessary amounts of herbicide to the weed-infested area
would be much more efficient and minimize
environmental damage. Therefore, a high spatial
resolution, real-time weed infestation detection system
Computer Graphics, Imaging and Visualisation (CGIV 2007)
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