A method for calibrating a velocimetry system, the velocimetry system including at least one camera for imaging an illuminated volume comprising moving particles according to at least two different fields of view, comprising: receiving preliminary imaging equations; simultaneously acquiring sets of images of the illuminated volume from the fields of view; voxelizing the illuminated volume; dividing each voxelized volume into interrogation volumes and generating templates images of each interrogation volume for each field of view using the preliminary imaging equations, identifying a match between given clusters of particles in the corresponding template image and corresponding clusters of particles in the corresponding set of images; determining position disparities between the given clusters of particles within the template image and the corresponding clusters of particles within the set of images; and for each field of view, modifying the corresponding preliminary imaging equations based on the determined disparities.

A method for calibrating a velocimetry system, the velocimetry system including at least one camera for imaging an illuminated volume comprising moving particles according to at least two different fields of view, comprising: receiving preliminary imaging equations; simultaneously acquiring sets of images of the illuminated volume from the fields of view; voxelizing the illuminated volume; dividing each voxelized volume into interrogation volumes and generating templates images of each interrogation volume for each field of view using the preliminary imaging equations, identifying a match between given clusters of particles in the corresponding template image and corresponding clusters of particles in the corresponding set of images; determining position disparities between the given clusters of particles within the template image and the corresponding clusters of particles within the set of images; and for each field of view, modifying the corresponding preliminary imaging equations based on the determined disparities.

An optical flow sensing method includes: using an image sensor to capture images; using a directional-invariant filter device upon at least one first block of the first image to process values of pixels of the at least one first block of the first image, to generate a first filtered block image; using the first directional-invariant filter device upon at least one first block of the second image to process values of pixels of the at least one first block of the second image, to generate a second filtered block image; comparing the filtered block images to calculate a correlation result; and estimating a motion vector according to a plurality of correlation results.

Provided is a technology capable of simply and efficiently obtaining a contrast of a speckle pattern as a prerequisite for measuring a fluid velocity.

The present technology provides an information processing apparatus including: a luminance integrator that integrates a luminance of a plurality of speckle images obtained by an imaging element by a plurality of times of imaging of scattered light obtained from an imaging target to which coherent light is emitted; and a contrast calculation unit that calculates a contrast of a speckle pattern on the basis of a speckle integrated image integrated by the luminance integrator.

A method for calibrating a velocimetry system, the velocimetry system including at least one camera for imaging an illuminated volume comprising moving particles according to at least two different fields of view, comprising: receiving preliminary imaging equations; simultaneously acquiring sets of images of the illuminated volume from the fields of view; voxelizing the illuminated volume; dividing each voxelized volume into interrogation volumes and generating templates images of each interrogation volume for each field of view using the preliminary imaging equations, identifying a match between given clusters of particles in the corresponding template image and corresponding clusters of particles in the corresponding set of images; determining position disparities between the given clusters of particles within the template image and the corresponding clusters of particles within the set of images; and for each field of view, modifying the corresponding preliminary imaging equations based on the determined disparities.

A method for determining the velocity of a moving fluid surface, which comprises the following steps S1 to S5: S1) taking a sequence of images of the moving fluid surface by at least one camera; S2) comparing a first image from the sequence with a second image from the sequence in order to distinguish moving patterns of the fluid surface from non-moving parts and to obtain a first processed image (im_1f) comprising the moving patterns; S3) comparing a third image from the sequence with a fourth image from the sequence in order to distinguish moving patterns of the fluid surface from non-moving parts and to obtain a second processed image (im_2f) comprising the moving patterns; S4) comparing the first and second processed images in order to determine the spatial displacements of the moving patterns; and S5) determining from the spatial displacements the velocity.

A method for determining the velocity of a moving fluid surface, which comprises the following steps S1 to S5: S1) taking a sequence of images of the moving fluid surface by at least one camera; S2) comparing a first image from the sequence with a second image from the sequence in order to distinguish moving patterns of the fluid surface from non-moving parts and to obtain a first processed image (im_1f) comprising the moving patterns; S3) comparing a third image from the sequence with a fourth image from the sequence in order to distinguish moving patterns of the fluid surface from non-moving parts and to obtain a second processed image (im_2f) comprising the moving patterns; S4) comparing the first and second processed images in order to determine the spatial displacements of the moving patterns; and S5) determining from the spatial displacements the velocity.

An ultrasound imaging system (100) includes a transducer array (102) that emits an ultrasound beam and produces at least one transverse pulse-echo field that oscillates in a direction transverse to the emitted ultrasound beam and that receive echoes produced in response thereto and a spectral velocity estimator (110) that determines a velocity spectrum for flowing structure, which flows at an angle of 90 degrees and flows at angles less than 90 degrees with respect to the emitted ultrasound beam, based on the received echoes.

An ultrasound imaging system (100) includes a transducer array (102) that emits an ultrasound beam and produces at least one transverse pulse-echo field that oscillates in a direction transverse to the emitted ultrasound beam and that receive echoes produced in response thereto and a spectral velocity estimator (110) that determines a velocity spectrum for flowing structure, which flows at an angle of 90 degrees and flows at angles less than 90 degrees with respect to the emitted ultrasound beam, based on the received echoes.

An ultrasound imaging system (100) includes a transducer array (102) that emits an ultrasound beam and produces at least one transverse pulse-echo field that oscillates in a direction transverse to the emitted ultrasound beam and that receive echoes produced in response thereto and a spectral velocity estimator (110) that determines a velocity spectrum for flowing structure, which flows at an angle of 90 degrees and flows at angles less than 90 degrees with respect to the emitted ultrasound beam, based on the received echoes.