Simultaneous remote extraction of multiple speech sources and heart beats from secondary speckles pattern

Abstract

The ability of dynamic extraction of remote sounds is very appealing. In this manuscript we propose an optical approach allowing the extraction and the separation of remote sound sources. The approach is very modular and it does not apply any constraints regarding the relative position of the sound sources and the detection device. The optical setup doing the detection is very simple and versatile. The principle is to observe the movement of the secondary speckle patterns that are generated on top of the target when it is illuminated by a spot of laser beam. Proper adaption of the imaging optics allows following the temporal trajectories of those speckles and extracting the sound signals out of the processed trajectory. Various sound sources are imaged in different spatial pixels and thus blind source separation becomes a very simple task.

Optical configuration of pigmented lesion detection by frequency analysis of skin speckle patterns

“…The use of such a concept was already demonstrated for non-contact biomedical monitoring including different biomedical parameters such as heart rate [39], non-invasive monitoring of glucose concentration in blood [40,41], remote estimation of alcohol in blood stream [42], blood pulse pressure [43] and measurement of intra ocular pressure [43,45].…”

Speckle pattern processing by digital image correlation

“…This method, which has found wide application in nondestructive testing of materials [9][10][11], is also a promising method of diagnostics in biology and medicine [7,[12][13][14][15]. The method of digital speckle correlation is also suitable for the remote measurement of microdisplacements and speed of various processes [15][16][17]. In [15] the authors realized audio signal extraction from vibrating objects located at a distance up to 100 m by means of the digital speckle correlation method.…”

“…The method of digital speckle correlation is also suitable for the remote measurement of microdisplacements and speed of various processes [15][16][17]. In [15] the authors realized audio signal extraction from vibrating objects located at a distance up to 100 m by means of the digital speckle correlation method. This fact points to the great prospects of the technique.…”

“…In [15] is shown that when optical system being used is properly configured, the displacement of an object under observation results in proportional transverse shift of the formed speckle pattern. This fact allows to detect the displacement as well as vibration of the object.…”

The Influence of the Radiation Source Parameters on the Accuracy of Digital Speckle Correlation Method

“…The authors [11] examined the optical system, which allows to extract information from vibrating objects located at the distance of 100 m using the method of digital speckle correlation, which demonstrates a great potential of this method. A number of other studies [12][13][14][15][16][17][18][19][20] also demonstrate the ability to read the information in this way.…”