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IS20 Detect audio files with very bad sound quality

Created by Bjarne Andersen on Sep 29, 2011 · last edited by Bjarne Andersen · on Sep 26, 2012 (view history) · 6 versions

Title	IS20 Detect audio files with very bad sound quality
Detailed description	In a collection of mp3 files (20 Tbytes - 360.000 files) we have discovered files with very bad sound quality. Before ingesting everything into our DOMS we would like to be able to discover the bad files and potentially get those re-digitized from the original analogue media.
Scalability Challenge	Large amounts of data (20 Tbytes - 360.000 files). We foresee that the process needed to solve this will require both I/O intensive work as well as heavy use of CPU for analysing the actual content.
Issue champion	Bjarne Andersen (SB)
Other interested parties
Possible Solution approaches	SB: Analyze WAV-form to detect high frequency nois. Test our commercial Dobbin Audio Analyser to see if this system detects problems with the files
Context
Lessons Learned
Training Needs
Datasets	mp3 (128kbit) with Danish Radio broadcasts
Solutions

Evaluation

Objectives	This issue is primarily about scaleability because we need to process 150.000 files reliability and preciseness since we need to detect files with very bad sound - files that we potentially will remove from the repository
Success criteria	When this issue is solved we will be able to scan through all files in our repository and automatically detect files with bad quality.
Automatic measures	Speed is not really important for this issue since this is a one time only job. Can't take years off cause. 1. Process 20 files per hour per node
Manual assessment	1. Non of the detected files are false positives (don't have bad sound quality)
Actual evaluations	links to acutual evaluations of this Issue/Scenario