Skip to content
Projects
Groups
Snippets
Help
Loading...
Help
Support
Keyboard shortcuts
?
Submit feedback
Contribute to GitLab
Sign in
Toggle navigation
L
licenseplates
Project overview
Project overview
Details
Activity
Releases
Repository
Repository
Files
Commits
Branches
Tags
Contributors
Graph
Compare
Issues
0
Issues
0
List
Boards
Labels
Milestones
Merge Requests
0
Merge Requests
0
CI / CD
CI / CD
Pipelines
Jobs
Schedules
Analytics
Analytics
CI / CD
Repository
Value Stream
Wiki
Wiki
Members
Members
Collapse sidebar
Close sidebar
Activity
Graph
Create a new issue
Jobs
Commits
Issue Boards
Open sidebar
Taddeüs Kroes
licenseplates
Commits
8b312b8c
Commit
8b312b8c
authored
Dec 14, 2011
by
Jayke Meijer
Browse files
Options
Browse Files
Download
Email Patches
Plain Diff
Corrected some grammatical errors.
parent
d3e13b6f
Changes
1
Show whitespace changes
Inline
Side-by-side
Showing
1 changed file
with
21 additions
and
21 deletions
+21
-21
docs/verslag.tex
docs/verslag.tex
+21
-21
No files found.
docs/verslag.tex
View file @
8b312b8c
...
...
@@ -39,8 +39,8 @@ Microsoft recently published a new and effective method to find the location of
text in an image.
Determining what character we are looking at will be done by using Local Binary
Patterns. The main goal of our research is finding out how effective LBPs are
in classifying characters on a licenseplate.
Patterns. The main goal of our research is finding out how effective LBP
'
s are
in classifying characters on a license
plate.
In short our program must be able to do the following:
...
...
@@ -145,9 +145,9 @@ stored in XML files. So, the first step is to read these XML files.\\
\paragraph*
{
Perspective transformation
}
Once we retrieved the cornerpoints of the licenseplate, we feed those to a
module that extracts the (warped) licenseplate from the original image, and
creates a new image where the licenseplate is cut out, and is transformed to a
Once we retrieved the cornerpoints of the license
plate, we feed those to a
module that extracts the (warped) license
plate from the original image, and
creates a new image where the license
plate is cut out, and is transformed to a
rectangle.
\subsection
{
Noise reduction
}
...
...
@@ -157,11 +157,11 @@ etc., as from dirt on the license plate. In this case, noise therefore means
any unwanted difference in color from the surrounding pixels.
\paragraph*
{
Camera noise and small amounts of dirt
}
The dirt on the licenseplate can be of different sizes. We can reduce the
The dirt on the license
plate can be of different sizes. We can reduce the
smaller amounts of dirt in the same way as we reduce normal noise, by applying
a
g
aussian blur to the image. This is the next step in our program.
\\
a
G
aussian blur to the image. This is the next step in our program.
\\
\\
The
g
aussian filter we use comes from the
\texttt
{
scipy.ndimage
}
module. We use
The
G
aussian filter we use comes from the
\texttt
{
scipy.ndimage
}
module. We use
this function instead of our own function, because the standard functions are
most likely more optimized then our own implementation, and speed is an
important factor in this application.
...
...
@@ -179,7 +179,7 @@ surrounding the character.
The retrieval of the character is done the same as the retrieval of the license
plate, by using a perspective transformation. The location of the characters on
the licenseplate is also available in de XML file, so this is parsed from that
the license
plate is also available in de XML file, so this is parsed from that
as well.
\subsection
{
Creating Local Binary Patterns and feature vector
}
...
...
@@ -200,12 +200,12 @@ available. These parameters are:\\
\begin{tabular}
{
l|l
}
Parameter
&
Description
\\
\hline
$
\sigma
$
&
The size of the
g
aussian blur.
\\
$
\sigma
$
&
The size of the
G
aussian blur.
\\
\emph
{
cell size
}
&
The size of a cell for which a histogram of LBPs will
be generated.
\\
$
\gamma
$
&
Parameter for the Radial kernel used in the SVM.
\\
$
c
$
&
The soft margin of the SVM. Allows how much training
errors are
ex
cepted.
errors are
ac
cepted.
\end{tabular}
\\
\\
For each of these parameters, we will describe how we searched for a good
...
...
@@ -225,10 +225,10 @@ that this was $\sigma = ?$.
The cell size of the Local Binary Patterns determines over what region a
histogram is made. The trade-off here is that a bigger cell size makes the
classification less affected by relative movement of a character compared to
those in the learningset, since the important structure will be more likely to
those in the learning
set, since the important structure will be more likely to
remain in the same cell. However, if the cell size is too big, there will not
be enough cells to properly describe the different areas of the character, and
the featurevectors will not have enough elements.
\\
the feature
vectors will not have enough elements.
\\
\\
In order to find this parameter, we used a trial-and-error technique on a few
basic cell sizes, being ?, 16, ?. We found that the best result was reached by
...
...
@@ -257,15 +257,15 @@ We found that the best values for these parameters are $c=?$ and $\gamma =?$.
\section
{
Results
}
The
wanted
to find out two things with this research: The speed of the
The
goal was
to find out two things with this research: The speed of the
classification and the accuracy. In this section we will show our findings.
\subsection
{
Speed
}
Recognizing license plates is something that has to be done
with good speed,
since there can be a lot of cars passing a camera
, especially on a highway.
Recognizing license plates is something that has to be done
fast, since there
can be a lot of cars passing a camera in a short time
, especially on a highway.
Therefore, we measured how well our program performed in terms of speed. We
measure the time used to classify a license plate, not the traini
gn
of the
measure the time used to classify a license plate, not the traini
ng
of the
dataset, since that can be done offline, and speed is not a primary necessity
there.
\\
\\
...
...
@@ -275,13 +275,13 @@ The speed of a classification turned out to be blablabla.
Of course, it is vital that the recognition of a license plate is correct,
almost correct is not good enough here. Therefore, we have to get the highest
accuracy score we possibly can. According to Wikipedia
accuracy score we possibly can.
\\
\\
According to Wikipedia
\footnote
{
\url
{
http://en.wikipedia.org/wiki/Automatic
_
number
_
plate
_
recognition
}}
,
commercial license plate recognition software score about
$
90
\%
$
to
$
94
\%
$
,
under optimal conditions and with modern equipment.
\\
\\
Our program scores an average of blablabla.
under optimal conditions and with modern equipment. Our program scores an
average of blablabla.
\section
{
Conclusion
}
...
...
Write
Preview
Markdown
is supported
0%
Try again
or
attach a new file
Attach a file
Cancel
You are about to add
0
people
to the discussion. Proceed with caution.
Finish editing this message first!
Cancel
Please
register
or
sign in
to comment