EQ2321 Speech and Audio Processing 7.5 credits
The course considers the foundational and advanced signal and information processing methods for human speech and natural audio signal applications, such as telephone conversation and music playing. For example, what kinds of information from human speech signal need to be extracted and then transmitted through the channel for effective speech communication over phone, and how?
(1) Preliminaries of associated digital signal processing methodologies, such as convolution, Z-transform, Fourier transform, power spectrum etc.
(2) A source-filter model: analysis-synthesis architecture.
(3) Source coding: scalar and vector quantization, redundancy removal, linear prediction, open loop and closed loop coding, coding noise buildup, coding noise shaping, coding gain.
(4) Speech and audio coding: vocoders, low bit rate and high bit rate codecs, perceptual audio coding, psychoacoustic principles.
(5) Speech and audio signal enhancement, minimum mean square error estimation, linear estimation for Gaussian distribution, Wiener filtering, power spectral subtraction methods, spectral band replication, etc.
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Application
For course offering
Spring 2025 Start 14 Jan 2025 programme students
Application code
60424
Content and learning outcomes
Course contents
The course considers the foundational and advanced signal and information processing methods for human speech and natural audio signal applications, such as telephone conversation and music playing. For example, what kinds of information from human speech signal need to be extracted and then transmitted through the channel for effective speech communication over phone, and how?
(1) Preliminaries of associated digital signal processing methodologies, such as convolution, Z-transform, Fourier transform, power spectrum etc.
(2) A source-filter model: analysis-synthesis architecture.
(3) Source coding: scalar and vector quantization, redundancy removal, linear prediction, open loop and closed loop coding, coding noise buildup, coding noise shaping, coding gain.
(4) Speech and audio coding: vocoders, low bit rate and high bit rate codecs, perceptual audio coding, psychoacoustic principles.
(5) Speech and audio signal enhancement, minimum mean square error estimation, linear estimation for Gaussian distribution, Wiener filtering, power spectral subtraction methods, spectral band replication, etc
Intended learning outcomes
After passing the course, students should be able to:
(1) Qualitatively describe the mechanisms of human speech production and how the articulation mode of different classes of speech sounds determines their acoustic characteristics.
(2) Apply programming tools (such as Matlab or Python) to analyze speech and audio signals in time and frequency domains, and in terms of the parameters of a source-filter production model and harmonic models.
(3) Critically analyze, compare and implement methods and systems for coding of speech and audio signals, and finally engineer efficient coding solutions.
(4) Analyze, compare and implement methods and systems for enhancement of speech and audio signals in environmental noisy conditions.
Literature and preparations
Specific prerequisites
For single course students: 120 credits and documented proficiency in
English B or equivalent
Recommended prerequisites
Recommended prerequisite: EQ1220 Signal Theory or EQ1270 Signal Processing
Equipment
Literature
Will be announced on the course homepage before course start. Preliminary literature:
(1) Digital speech transmission: Enhancement, coding and error concealment. By Peter Vary and Rainer Martin.
(2) Perceptual coding of digital audio. By Ted Painter and Andreas Spanias.
(3) Notes of the class teacher. This can be downloaded from the course website.
(4) Some research papers.
Examination and completion
If the course is discontinued, students may request to be examined during the following two academic years.
Grading scale
Examination
- PRO1 - Project 1, 1.5 credits, grading scale: A, B, C, D, E, FX, F
- PRO2 - Project 2, 1.5 credits, grading scale: A, B, C, D, E, FX, F
- TEN1 - Exam, 4.5 credits, grading scale: A, B, C, D, E, FX, F
Based on recommendation from KTH’s coordinator for disabilities, the examiner will decide how to adapt an examination for students with documented disability.
The examiner may apply another examination format when re-examining individual students.
Other requirements for final grade
There are three assessment components for the course.
(1) Master tests: There will be two master tests in the span of teaching 14 classes. Each test is of 20-30 minutes. The master tests are intended to check concepts and require sustained (or regular) study at home as the teachers cover topics in class. The tests will use short conceptual questions, and no lengthy problem. Grades for master tests: A-F.
(2) Projects: There are two projects. Projects are examined via presentations. Projects can be performed in groups of two persons. However, the grades are on the basis of individual performance. Grades for projects: A-F.
(3) Written exam: There is a final written exam. Grades for the final exam: A-F.
The overall grade of the course is based on collective performance. The teacher will provide weights to all tests for the overall grade.
To pass the course, master tests are not mandatory. But the projects and final test are mandatory. To achieve a good course grade, a student is expected to perform well in all the three assessment components.
Opportunity to complete the requirements via supplementary examination
Opportunity to raise an approved grade via renewed examination
Examiner
Ethical approach
- All members of a group are responsible for the group's work.
- In any assessment, every student shall honestly disclose any help received and sources used.
- In an oral assessment, every student shall be able to present and answer questions about the entire assignment and solution.
Further information
Course room in Canvas
Offered by
Main field of study
Education cycle
Add-on studies
Supplementary information
In this course, the EECS code of honor applies, see: http://www.kth.se/en/eecs/utbildning/hederskodex.