3,210 research outputs found
Handwriting Recognition of Historical Documents with few labeled data
Historical documents present many challenges for offline handwriting
recognition systems, among them, the segmentation and labeling steps. Carefully
annotated textlines are needed to train an HTR system. In some scenarios,
transcripts are only available at the paragraph level with no text-line
information. In this work, we demonstrate how to train an HTR system with few
labeled data. Specifically, we train a deep convolutional recurrent neural
network (CRNN) system on only 10% of manually labeled text-line data from a
dataset and propose an incremental training procedure that covers the rest of
the data. Performance is further increased by augmenting the training set with
specially crafted multiscale data. We also propose a model-based normalization
scheme which considers the variability in the writing scale at the recognition
phase. We apply this approach to the publicly available READ dataset. Our
system achieved the second best result during the ICDAR2017 competition
Curriculum Learning for Handwritten Text Line Recognition
Recurrent Neural Networks (RNN) have recently achieved the best performance
in off-line Handwriting Text Recognition. At the same time, learning RNN by
gradient descent leads to slow convergence, and training times are particularly
long when the training database consists of full lines of text. In this paper,
we propose an easy way to accelerate stochastic gradient descent in this
set-up, and in the general context of learning to recognize sequences. The
principle is called Curriculum Learning, or shaping. The idea is to first learn
to recognize short sequences before training on all available training
sequences. Experiments on three different handwritten text databases (Rimes,
IAM, OpenHaRT) show that a simple implementation of this strategy can
significantly speed up the training of RNN for Text Recognition, and even
significantly improve performance in some cases
Learning Spatial-Semantic Context with Fully Convolutional Recurrent Network for Online Handwritten Chinese Text Recognition
Online handwritten Chinese text recognition (OHCTR) is a challenging problem
as it involves a large-scale character set, ambiguous segmentation, and
variable-length input sequences. In this paper, we exploit the outstanding
capability of path signature to translate online pen-tip trajectories into
informative signature feature maps using a sliding window-based method,
successfully capturing the analytic and geometric properties of pen strokes
with strong local invariance and robustness. A multi-spatial-context fully
convolutional recurrent network (MCFCRN) is proposed to exploit the multiple
spatial contexts from the signature feature maps and generate a prediction
sequence while completely avoiding the difficult segmentation problem.
Furthermore, an implicit language model is developed to make predictions based
on semantic context within a predicting feature sequence, providing a new
perspective for incorporating lexicon constraints and prior knowledge about a
certain language in the recognition procedure. Experiments on two standard
benchmarks, Dataset-CASIA and Dataset-ICDAR, yielded outstanding results, with
correct rates of 97.10% and 97.15%, respectively, which are significantly
better than the best result reported thus far in the literature.Comment: 14 pages, 9 figure
- …