3 research outputs found
Does color modalities affect handwriting recognition? An empirical study on Persian handwritings using convolutional neural networks
Most of the methods on handwritten recognition in the literature are focused
and evaluated on Black and White (BW) image databases. In this paper we try to
answer a fundamental question in document recognition. Using Convolutional
Neural Networks (CNNs), as eye simulator, we investigate to see whether color
modalities of handwritten digits and words affect their recognition accuracy or
speed? To the best of our knowledge, so far this question has not been answered
due to the lack of handwritten databases that have all three color modalities
of handwritings. To answer this question, we selected 13,330 isolated digits
and 62,500 words from a novel Persian handwritten database, which have three
different color modalities and are unique in term of size and variety. Our
selected datasets are divided into training, validation, and testing sets.
Afterwards, similar conventional CNN models are trained with the training
samples. While the experimental results on the testing set show that CNN on the
BW digit and word images has a higher performance compared to the other two
color modalities, in general there are no significant differences for network
accuracy in different color modalities. Also, comparisons of training times in
three color modalities show that recognition of handwritten digits and words in
BW images using CNN is much more efficient
Ensemble learning using multi-objective optimisation for arabic handwritten words
Arabic handwriting recognition is a dynamic and stimulating field of study within
pattern recognition. This system plays quite a significant part in today's global
environment. It is a widespread and computationally costly function due to cursive
writing, a massive number of words, and writing style. Based on the literature, the
existing features lack data supportive techniques and building geometric features.
Most ensemble learning approaches are based on the assumption of linear
combination, which is not valid due to differences in data types. Also, the existing
approaches of classifier generation do not support decision-making for selecting the
most suitable classifier, and it requires enabling multi-objective optimisation to handle
these differences in data types. In this thesis, new type of feature for handwriting using
Segments Interpolation (SI) to find the best fitting line in each of the windows with a
model for finding the best operating point window size for SI features. Multi-Objective
Ensemble Oriented (MOEO) formulated to control the classifier topology and provide
feedback support for changing the classifiers' topology and weights based on the
extension of Non-dominated Sorting Genetic Algorithm (NSGA-II). It is designated
as the Random Subset based Parents Selection (RSPS-NSGA-II) to handle neurons
and accuracy. Evaluation metrics from two perspectives classification and Multiobjective
optimization. The experimental design based on two subsets of the
IFN/ENIT database. The first one consists of 10 classes (C10) and 22 classes (C22).
The features were tested with Support Vector Machine (SVM) and Extreme Learning
Machine (ELM). This work improved due to the SI feature. SI shows a significant
result with SVM with 88.53% for C22. RSPS for C10 at k=2 achieved 91% accuracy
with fewer neurons than NSGA-II, and for C22 at k=10, accuracy has been increased
81% compared to NSGA-II 78%. Future work may consider introducing more features
to the system, applying them to other languages, and integrating it with sequence
learning for more accuracy