Using an encephalogram UNal researchers will measure how a human being perceives audio
UN/DICYT As determined by Professor and Director of the Universidad Nacional de Colombia (UNal) Applied Electromagnetic Propagation Laboratory (PROPELA, for its Spanish acronym ) in Manizales, Julio César García who says that tests to measure audio quality are very arguable, because for different people the same noise may be considered creative, artistic or invasive.
“A noise which may be harmonious to one person can be the opposite for another. To measure this we cannot only fill in a survey on the individual experience but obtain assistance from technology, in this particular case a portable encephalogram,” said García. In quoting scientists Thomas Wiegand, who was at a congress he also attended in Berlin, he said, “We need to search a way to read human thoughts.”
Then master’s candidate Santiago Ordóñez said the test implies different types of files which will enable establishing (using 16 channels) the reaction of the brain in face of voice perception when it is a woman or a man signing or if it is the melody which triggers one or the other brain hemisphere.
“Up to now we know that when it is a song, both brain hemispheres become activated; but we want to go further and know, for instance, if a person pays more attention to the music or the voice,” said Ordoñez who is also in charge of assessing the audio equipment part of the research project.
The project chosen by and funded by the Manizales Research and Extension Directorate (DIMA, for its Spanish acronym), hopes to determine objective and perceptible criteria of the content perceived from YouTube, Netflix and Google, among other networks.
According to the researchers, the goal is to observe an image which may be blurred, unfocused or scratched. However, from the perceptual perspective this may produce a pleasant or unpleasant sensation on the viewer.
In its beginnings which were back in 2013, the group of researchers, which also includes a student incubator which designed a portable device for receiving music online, began researching imagery, whose topic was telemedicine and based on the idea that a correct or incorrect medical diagnosis basically depended on what was observed.
“We worked with face recognition, microscopy and thermographic imagery, the former with support from Hernán Benítez, a Universidad Javeriana in Cali Professor who showed us that a camera can change according to weather conditions. We will know what motivates people to assess music quality as good or bad and determine the criteria to maximize multimedia equipment,” he said.
Companies such as Google, YouTube and others, such as public utilities companies for instance, should be evaluated to determine how their content is received by the user, beyond technical considerations.
“Furthermore, whatever technology we use, they will always be accompanied by a survey as required by the International Telecommunication Union (ITU),” said García.
The second stage of the research project will begin in a month and hopes to measure the quality of the experience in multimedia networks.