A Review of Physical and Perceptual Feature Extraction Techniques for Speech, Music and Environmental Sounds
Francesc Alias●3 comments
Endowing machines with sensing capabilities similar to those of humans is a prevalent quest in engineering and computer science. In the pursuit of making computers sense their surroundings, a huge effort has been conducted to allow machines and computers to acquire, process, analyze and understand their environment in a human-like way. Focusing on the sense of hearing, the ability of computers to sense their acoustic environment as humans do goes by the name of machine hearing. To achieve this ambitious aim, the representation of the audio signal is of paramount importance. In this paper, we present an up-to-date review of the most relevant audio feature extraction techniques developed to analyze the most usual audio signals: speech, music and environmental sounds. Besides revisiting classic approaches for completeness, we include the latest advances in the field based on new domains of analysis together with novel bio-inspired proposals. These approaches are described following a taxonomy that organizes them according to their physical or perceptual basis, being subsequently divided depending on the domain of computation (time, frequency, wavelet, image-based, cepstral, or other domains). The description of the approaches is accompanied with recent examples of their application to machine hearing related problems.
Faculty Resources: Using the DSP essays in class
Using Students’ DSP Essays in Class
Connecting assessment to instruction is one of the guiding principles of the Wake Forest Directed Self-Placement (DSP) process. The following are possible ways you could use the DSP essay in your class. Please let me know if you think of any to add to the list!
- Read the essays before classes begin to assess student learning needs and prioritize topics for individual and group instruction.
- Ask students to re‐read their essays at the beginning of class and write a “self‐diagnosis” of their strengths and needs as a writer, based upon their re‐reading.
- Have students develop a list of three specific writing‐related goals, based on strengths and weaknesses identified in their DSP essays. Then have students free‐write and/or discuss ways they intend to implement a plan to achieve these goals.
Analysis of Academic Writing
- Have students use a framework already used for academic writing on their own writing, such as John Swales’ Creating A Research Space (CaRS) model (1990) for academic introductions.
- Have students analyze their own writing for features you expect them to use in their writing, such as hedges (e.g., perhaps, might, likely) in order to make more measured arguments (e.g., Hyland 2005).
Engaging in the Writing Process
- Ask students to recall their experience of writing the DSP essay and write reflectively about it. Encourage use of concrete examples. Ask: “Based on this experience, how do you plan to approach writing assignments for this course and other courses?”
- Have the students list on the board problems they encountered as well as successes they experienced while writing the essays. Discuss as a class.
Workshop/Peer Review Practice
- Have students read and comment on sample DSP essays from volunteers in the class. Conduct a full‐class discussion of the essays and lead a workshop to model expectations for peer review.
Office Hours or Conferencing
- Use the DSP essays as a vehicle to schedule brief one‐to‐one conversations or office hours with students early in the term.
- Use the DSP essay as a point of departure to compare expectations, discuss goals for the semester, and examine students’ strengths and weaknesses as writers.
Teaching Audience Awareness
- Have students describe or write about the “imagined audience” for their essays when teaching on rhetoric/audience. Have them revise the essays for different audiences, or discuss how they might go about doing so.
Evaluating Summarizing Skills
- Have students identify in their essays where they summarized arguments from the article. Ask: “How do you distinguish summary from analysis?”
- Ask students to read their summary sections aloud in pairs, and discuss how they might revise to be more comprehensive or appropriate.
Teaching Thesis and Evaluation
- In pairs, have students identify their thesis statements and work to refine them.
- Have students create a “reverse outline” of their essay, listing their argument’s main points from each paragraph. Ask: “What might you change, add, subtract, or reorganize to better support your central argument?”
Teaching Nuance and Complexity
- Using the DSP essays, ask students to consider “Nuance & Complexity” in their own arguments. Discuss what it means to acknowledge other perspectives and to avoid sweeping generalizations, in the interest of making nuanced and complex assertions in academic writing.
Teaching Evidence and Quotation
- In groups, have students list the evidence used in the article to support its claims. Then ask students to look at their own essays, alone or in pairs or groups, to identify the evidence they used in support of the assertions they made. Discuss the differences.
- Have students read their essays and identify places where they integrated material from the article into their writing, distinguishing instances of direct quotation, paraphrase, and summary. Ask them to consider the effectiveness of each instance.
Gaining Experience with Rubrics
- Have students brainstorm a list of qualities of “good college writing.” Compare these to features students find in their own essays and discuss in class.
- Have students evaluate their own DSP essay vis-à-vis your course rubric (or the rubric you will use for the first writing assignment, if you use more than one). Have students work in pairs and then ask questions as a class to clarify writing expectations.
- Use the DSP rubric to have students evaluate each other’s DSP essays. Then have them consider how to use this feedback for goal‐setting.
Mid-Term or End-of-Term Assessment
- At the midpoint or end of the semester, ask students to self‐assess their development by having them re‐read their DSP Essay and compare it to a recent course paper. Ask them to write about how their writing has changed.
- Have students revisit the essays and write a letter to themselves, pointing out how they might approach the task differently, or describing improvements they’ve noticed, or issues that remain.
- Include the DSP essays in a portfolio of coursework, along with reflective pieces on their writing development from the DSP essay until now.