Index

Self-supervised learning for pathology classification

Motivation
Self-supervised learning is a promising approach in the field of speech processing. The capacity to learn
representations from unlabelled data with minimal feature-engineering efforts results in increased
independence from labelled data. This is particularly relevant in the pathological speech domain, where the
amount of labelled data is limited. However, as most research focuses on healthy speech, the effect of selfsupervised
learning on pathological speech data remains under-researched. This motivates the current
research as pathological speech will potentially benefit from the self-supervised learning approach.
Proposed Method
Self-supervised machine learning helps make the most out of unlabeled data for training a model. Wav2vec
2.0 will be used, an algorithm that almost exclusively uses raw, unlabeled audio to train speech
representations [1][2]. These can be used as input feature alternatives to traditional approaches using Mel-
Frequency Cepstral Coefficients or log-mel filterbanks for numerous downstream tasks. To evaluate the
performance of these trained representations, it will be examined how well they perform on a binary
classification task where the model predicts whether or not the input speech is pathological.
A novel database containing audio files in German collected using the PEAKS software [3] will be used.
Here, patients with speech disorders, such as dementia, cleft lip, and Alzheimer’s Disease, were recorded
performing two different speech tasks: picture reading in !!Psycho-Linguistische Analyse Kindlicher Sprech-
Störungen” (PLAKSS) and “The North Wind and the Sun” (Northwind) [3]. As the database is still being
revised, some pre-processing of the data must be performed, for example, removing the voice of a (healthy)
therapist from the otherwise pathological recordings. After preprocessing, the data will be input to the
wav2vec 2.0 framework for self-supervised learning, which will be used as a pre-trained model in the
pathology classification task.
Hypothesis
Given the benefits of acquiring learned representations without labelled data, the hypothesis is that the selfsupervised
model’s classification experiment will outperform the approach without self-supervision. The
results of the pathological speech detection downstream task are expected to show the positive effects of
pre-trained representations obtained by self-supervised learning.
Furthermore, the model is expected to enable automatic self-assessment for the patients using minimallyinvasive
methods and assist therapists by providing objective measures in their diagnosis.
Supervisions
Professor Dr. Andreas Maier, Professor Dr. Seung Hee Yang, M. Sc. Tobias Weise
References
[1] Schneider, S., Baevski, A., Collobert, R., Auli, M. (2019) wav2vec: Unsupervised Pre-Training for
Speech Recognition. Proc. Interspeech 2019, 3465-3469
[2] A. Baevski, Y. Zhou, A. Mohamed, and M. Auli, “wav2vec 2.0: A Framework for Self-Supervised
Learning of Speech Representations,” in Advances in Neural Information Processing Systems. 2020, vol. 33,
pp. 12449–12460, Curran Associates, Inc.
[3] Maier, A., Haderlein, T., Eysholdt, U., Rosanowski, F., Batliner, A., Schuster, M., Nöth, E., Peaks – A
System for the automatic evaluation of voice and speech disorders, Speech Communication (2009)

Classical Acoustic Markers for Depression in Parkinson’s Disease

Parkinson’s disease (PD) patients are commonly recognized for their tremors, although there is a wide range of different symptoms of PD. This is a progressive neurological condition, where patients do not have enough dopamine in the substancia nigra, which plays a role in motor control, mood, and cognitive functions. A really underestimated type of symptoms in PD is the mental and behavioral issues, which can manifest in depression, fatigue, or dementia. Clinical depression is a psychiatric mood disorder, caused by an individual’s difficulty in coping with stressful life events, and presents persistent feelings of sadness, negativity, and difficulty managing everyday responsibilities. This can be triggered by the lack of dopamine from PD, the upsetting and stressful situation of the Parkinson’s diagnosis as well as by the loneliness and isolation that can be caused by the Parkinson’s symptoms.
The goal of this work is to find the most suitable acoustic features that can discriminate against depression in Parkinson’s patients. Those features will be based on classical and interpretable acoustic descriptors.

Cone-Beam CT X-Ray Image Simulation for the Generation of Training Data

Fruit Terminator – Annotation of Lung Fluid Cells via Gamification

Letter Inpainting and Detection of Mathematical Diagrams in Multi-Lingual Manuscripts using a Deep Neural Network approach

Exploring Style-transfer techniques on Greek vase paintings for enhancing pose-estimation

The German Phonetic Footprint of Parkinsons Disease

Character Height Estimation in Historical Document Images

During past decades, the field of Document Image Analysis and Recognition (DIAR) has been the subject of many researches due to its wide range of applications. DIAR can be applied to either printed or handwritten, textual or graphical document images with the purpose of automatically analyzing their contents in order to retrieve useful information [1, 2]. The applications of DIAR arise in different fields such as the storage and indexing of cultural heritage by analyzing historical manuscripts. Text detection and recognition in imagery are two key components of most techniques in DIAR [3, 4]. Since the existing methods for text detection rely on texture estimation [5] or edge detection [6] as stated by Wolf et al. [7], the text characteristics may affect the document analysis. For this reason, text recognition pipelines typically resize text lines to a specific height which is the one they were trained
on.
In this thesis, the influence of the text height on document analysis is investigated. Document resizing
to a specific text height will be inserted as first step of several DIAR methods for running experiments. The thesis consists of the following milestones:
• Producing a data set with text height labeled for a sufficient amount of ancient books and
manuscripts [8, 9].
• Developing a system which detects text in the documents and resizes it to a predetermined height
in pixels.
• Running various experiments to determine whether this improves the results of different DIAR
methods.

[1] Deepika Ghai and Neelu Jain. Text extraction from document images-a review. International Journal of Computer Applications, 84(3), 2013.
[2] Vikas Yadav and Nicolas Ragot. Text extraction in document images: Highlight on using corner points. In 2016 12th IAPR Workshop on Document Analysis Systems (DAS), pages 281–286, 2016.
[3] Xinyu Zhou, Cong Yao, He Wen, Yuzhi Wang, Shuchang Zhou, Weiran He, and Jiajun Liang. East: an efficient and accurate scene text detector. In Proceedings of the IEEE conference on Computer Vision and Pattern Recognition, pages 5551–5560, 2017.
[4] Adam Coates, Blake Carpenter, Carl Case, Sanjeev Satheesh, Bipin Suresh, Tao Wang, David J Wu, and Andrew Y Ng. Text detection and character recognition in scene images with unsupervised feature learning. In 2011 International Conference on Document Analysis and Recognition, pages 440–445. IEEE, 2011.
[5] Bangalore S Manjunath and Wei-Ying Ma. Texture features for browsing and retrieval of image data. IEEE Transactions on pattern analysis and machine intelligence, 18(8):837–842, 1996.
[6] Chung-Ching Chen et al. Fast boundary detection: A generalization and a new algorithm. IEEE Transactions on computers, 100(10):988–998, 1977.
[7] Christian Wolf, Jean-Michel Jolion, and LIRIS INSA de Lyon. Model based text detection in images and videos: a learning approach. Laboratoire dInfoRmatique en Images et Systemes dinformation, Palmas, TO, 2004.
[8] Vincent Christlein, Anguelos Nicolaou, Mathias Seuret, Dominique Stutzmann, and Andreas Maier. Icdar 2019 competition on image retrieval for historical handwritten documents. In 2019 International Conference on Document Analysis and Recognition (ICDAR), pages 1505–1509. IEEE, 2019.
[9] https://lme.tf.fau.de/competitions/icdar-2021-competition-on-historical-document-classification.

Digitization of Handwritten Rey Osterrieth Complex Figure Test Score Sheets

The Rey Osterrieth Complex Figure Test (ROCF) is a neuropsychological test to detect cognitive
impairments.
As the scoring is mostly implemented by hand from experts the goal is to automate the ROCF by
means of machine learning.
The whole project consists of four milestones:
1. State-of-the-art literature research
2. Development of an OCR-based algorithm to digitize the handwritten score sheet into machine
readable structured format for training an automatic algorithm
3. Development of a deep learning algorithm for automatic scoring ROFCs based on the 36-point
scoring system
4. Evaluation of the algorithm based on the data and publication of the results
This thesis will mainly examine the first two steps.
The used scoring sheets consist of an identical structure and just the score itself is handwritten.
Therefore only digits have to be recognized.
The idea is to use networks already trained on the MNIST database (e.g. [1], [2], [3]) and to gain the
best outcome performance for the described issue.
Therefore some preprocessing of the scanned scoring sheets such as detecting areas of interest, binari-
zation or rotation will be necessary to match the requirements for input data of the specific algorithms
as well as for improving performance.
Other options for preprocessing could be template matching or taking advantage of the HU-moments
[4]. Hereby text detection, i.e. finding areas of interests, is one of the typically performed steps in any
text processing pipeline [5].
Furthermore modifying algorithms and weights will be used to achieve different outcomes which than
can be compared in relation to their performances.
The implementation should be done in Python.

References
[1] Gargi Jha. Mnist handwritten digit recognition using neural network, Sep 2020.
[2] Muhammad Ardi. Simple neural network on mnist handwritten digit dataset, Sep 2020.
[3] Dan Claudiu Ciresan, Ueli Meier, Luca Maria Gambardella, and Jürgen Schmidhuber. Deep big simple
neural nets excel on handwritten digit recognition. CoRR, abs/1003.0358, 2010.
[4] Zengshi Chen, Emmanuel Lopez-Neri, Snezana Zekovich, and Milan Tuba. Hu moments based handwritten
digits recognition algorithm. In Recent advances in knowledge engineering and systems science: Proceedings
of the 12TH international conference on artificial intelligence, knowledge engineering and data bases, page
98–104. WSEAS Press, 2013.
[5] Simon Hofmann, Martin Gropp, David Bernecker, Christopher Pollin, Andreas Maier, and Vincent Christlein.
Vesselness for text detection in historical document images. In 2016 IEEE International Conference on
Image Processing (ICIP), pages 3259–3263, 2016.

Learnable Feature Space Reductions for Acoustic Representation Vectors