Making the text more constant
This commit is contained in:
parent
08813f9b9f
commit
7ccbb169ca
@ -194,21 +194,20 @@
|
||||
|
||||
The Waldo image database consists of images of size 64$\times$64,
|
||||
128$\times$128, and 256$\times$256 pixels obtained by dividing complete
|
||||
Where's Waldo? puzzles. Within each set of images, those containing Waldo
|
||||
are located in a folder called `waldo', and those not containing Waldo, in a
|
||||
folder called `not\_waldo'. Since Where's Waldo? puzzles are usually densely
|
||||
populated and contain fine details, the 64$\times$64 pixel set of images
|
||||
were selected to train and evaluate the machine learning models. These
|
||||
images provide the added benefit of containing the most individual images of
|
||||
the three size groups. \\
|
||||
``Where's Waldo?'' puzzles. Within each set of images, those containing
|
||||
Waldo are located in a folder called \texttt{waldo}, and those not containing
|
||||
Waldo, in a folder called \texttt{not\_waldo}. Since ``Where's Waldo?''
|
||||
puzzles are usually densely populated and contain fine details, the
|
||||
64$\times$64 pixel set of images were selected to train and evaluate the
|
||||
machine learning models. These images provide the added benefit of
|
||||
containing the most individual images of the three size groups. \\
|
||||
|
||||
Each of the 64$\times$64 pixel images were inserted into a
|
||||
Numpy~\cite{numpy} array of images, and a binary value was inserted into a
|
||||
seperate list at the same index. These binary values form the labels for
|
||||
each image (waldo or not waldo). Colour normalisation was performed on each
|
||||
so that artefacts in an image's colour profile correspond to meaningful
|
||||
features of the image (rather than photographic method).\\
|
||||
|
||||
separate list at the same index. These binary values form the labels for
|
||||
each image (``Waldo'' or ``not Waldo''). Color normalization was performed
|
||||
on each so that artifacts in an image's color profile correspond to
|
||||
meaningful features of the image (rather than photographic method).\\
|
||||
|
||||
Each original puzzle is broken down into many images, and only contains one
|
||||
Waldo. Although Waldo might span multiple 64$\times$64 pixel squares, this
|
||||
@ -222,27 +221,27 @@
|
||||
methods by exposing each technique to variations of the image during the
|
||||
training phase. \\
|
||||
|
||||
Despite the additional data, there were still over ten times as many
|
||||
non-Waldo images than Waldo images. Therefore, it was necessary to cull the
|
||||
no-Waldo data, so that there was an even split of Waldo and non-Waldo
|
||||
images, improving the representation of true positives in the image data
|
||||
set. Following preprocessing, the images (and associated labels) were
|
||||
divided into a training and a test set with a 3:1 split. \\
|
||||
Despite the additional data, there were still ten times more ``non-Waldo''
|
||||
images than Waldo images. Therefore, it was necessary to cull the
|
||||
``non-Waldo'' data, so that there was an even split of ``Waldo'' and
|
||||
``non-Waldo'' images, improving the representation of true positives in the
|
||||
image data set. Following preprocessing, the images (and associated labels)
|
||||
were divided into a training and a test set with a 3:1 split. \\
|
||||
|
||||
\subsection{Neural Network Training}\label{nnTraining}
|
||||
|
||||
The neural networks used to classify the images were supervised learning
|
||||
models; requiring training on a dataset of typical images. Each network was
|
||||
trained using the preprocessed training dataset and labels, for 25 epochs
|
||||
trained using the preprocessed training dataset and labels for 25 epochs
|
||||
(one forward and backward pass of all data) in batches of 150. The number of
|
||||
epochs was chosen to maximise training time and prevent overfitting of the
|
||||
epochs was chosen to maximize training time and prevent overfitting of the
|
||||
training data, given current model parameters. The batch size is the number
|
||||
of images sent through each pass of the network. Using the entire dataset
|
||||
would train the network quickly, but decrease the network's ability to learn
|
||||
unique features from the data. Passing one image at a time may allow the
|
||||
model to learn more about each image, however it would also increase the
|
||||
training time and risk of overfitting the data. Therefore the batch size was
|
||||
chosen to maintain training accuracy while minimising training time.
|
||||
chosen to maintain training accuracy while minimizing training time.
|
||||
|
||||
\subsection{Neural Network Testing}\label{nnTesting}
|
||||
|
||||
|
Reference in New Issue
Block a user