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Record W1600556455

Audio processing in police investigations

2004· article· en· W1600556455 on OpenAlexaffvenueabout
David Luknowsky, Jeff Boyczuk

Bibliographic record

VenueCanadian acoustics · 2004
Typearticle
Languageen
FieldComputer Science
TopicSpeech and Audio Processing
Canadian institutionsRoyal Canadian Mounted Police
Fundersnot available
KeywordsAcousticsFilter (signal processing)Computer scienceAdaptive filterSpeech recognitionFrequency spectrumTone (literature)TelecommunicationsComputer visionPhysicsSpectral densityAlgorithm
DOInot available

Abstract

fetched live from OpenAlex

The various methods applied by the Audio and Video Analysis Section of the Royal Canadian Mounted Police (RCMP) to reduce the interferences and improve the intelligibility of audio recordings are discussed. Hum, a kind of tone which comes from powerlines and fluorescent lights can be removed with a comb filter. A series of individual tones at unequally spaced frequencies or tones whose frequency varies can be solved with the help of an adaptive filter. If tones are strong yet stationary and unevenly spaced, it can be removed with an inverse filter. A spectralinverse filter with shaping provides an amplitude boost to high voice frequencies and shape the spectrum to an averaged voice spectrum.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.

metaresearch head score (Codex)0.001
metaresearch head score (Gemma)0.003
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Not applicable · Consensus signal: none
GenreCandidate signal: Empirical · Consensus signal: none
Teacher disagreement score0.010
Threshold uncertainty score0.030

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0010.003
Meta-epidemiology (narrow)0.0010.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0030.002
Science and technology studies0.0010.001
Scholarly communication0.0030.001
Open science0.0010.001
Research integrity0.0010.001
Insufficient payload (model declined to judge)0.0090.004

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.015
GPT teacher head0.231
Teacher spread0.216 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designNot applicable
Domainnot available
GenreEmpirical

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations0
Published2004
Admission routes3
Has abstractyes

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