Abstract: A method for processing at least one digital image for reproduction on a display device. The image includes image elements, an image element being associated with color information having, in a first color space, a luminance component and chrominance components. The method includes the following acts: determining a number of image elements, known as “bright” elements, at least the luminance component of which has a value greater than a first predetermined threshold; evaluating a maximum tolerated brightness value as a decreasing function of the number of counted image elements; and transforming the first luminance components of the image elements to second luminance components, including for an image element, calculating an intermediate luminance value by applying an expansion exponent to the first luminance component value and multiplying the intermediate value calculated by the evaluated maximum tolerated luminosity value.

Abstract: A method for processing a digital image including image elements having a first luminance component. The first luminance component has a first value in a first predetermined interval. The display can render second values of second luminance components included in a second predetermined interval. The method includes: determining information representative of image brightness perceived by an observer, based on the first values of the first luminance component; calculating an expansion exponent as a function of the determined brightness information; transforming the first luminance components into the second luminance components, including calculating an intermediate luminance value by applying the calculated expansion exponent to the first luminance component value, multiplying the intermediate value by a length of the second interval, and obtaining the second value of the second luminance component based on the multiplied intermediate luminance value.

Abstract: A method for processing a digital image including image elements having a first luminance component. The first luminance component has a first value in a first predetermined interval. The display can render second values of second luminance components included in a second predetermined interval. The method includes: determining information representative of image brightness perceived by an observer, based on the first values of the first luminance component; calculating an expansion exponent as a function of the determined brightness information; transforming the first luminance components into the second luminance components, including calculating an intermediate luminance value by applying the calculated expansion exponent to the first luminance component value, multiplying the intermediate value by a length of the second interval, and obtaining the second value of the second luminance component based on the multiplied intermediate luminance value.

Abstract: A method for processing at least one digital image for reproduction on a display device. The image includes image elements, an image element being associated with color information having, in a first color space, a luminance component and chrominance components. The method includes the following acts: determining a number of image elements, known as “bright” elements, at least the luminance component of which has a value greater than a first predetermined threshold; evaluating a maximum tolerated brightness value as a decreasing function of the number of counted image elements; and transforming the first luminance components of the image elements to second luminance components, including for an image element, calculating an intermediate luminance value by applying an expansion exponent to the first luminance component value and multiplying the intermediate value calculated by the evaluated maximum tolerated luminosity value.

Abstract: A method for digitally generating a hologram plane from a three-dimensional scene, cut into a plurality of planes parallel to the hologram plane. The method includes for a current plane: counting a number of points of the non-zero amplitude scene; choosing a first or second technique for propagating a light wave emitted by the current plane as a function of a number of points of non-zero amplitude included in the current plane and with a preset threshold value, the first, point-based technique calculating the propagation of a sum of light waves emitted by point sources constituted by the points of the scene portion of a non-zero amplitude of the current plane on a following plane, and the second, field-based technique, globally calculating a light wave emitted by the scene portion situated in the current plane on a given plane; and processing the current plane according to the chosen propagation technique.

Abstract: A method and device for processing LDR images of a video sequence to improve image quality. The method comprises temporally decomposing successive HDR frames of a video sequence and the corresponding LDR frames and performing a comparison between the HDR and LDR frequency sub-bands. A current LDR image can then be modified on the basis of a comparison between the frequency sub-bands.

Abstract: A method for processing a digital image for rendering on a display. The image includes image elements associated with color information represented in a colorimetric space having a luminance and chrominance components. The luminance component has a value in a first predetermined interval. The display can render values of luminance components included in a second predetermined interval, of greater length than the first interval. The method includes: determining information representative of image brightness perceived by an observer, based on the values of the first luminance component; calculating an expansion exponent as a function of the determined brightness information; transforming the first luminance components into second luminance components, including calculating an intermediate luminance value by applying the calculated expansion exponent to the first luminance component value and multiplying the intermediate value by the length of the second interval.

Abstract: A method for processing a digital image for rendering on a display. The image includes image elements associated with color information represented in a colorimetric space having a luminance and chrominance components. The luminance component has a value in a first predetermined interval. The display can render values of luminance components included in a second predetermined interval, of greater length than the first interval. The method includes: determining information representative of image brightness perceived by an observer, based on the values of the first luminance component; calculating an expansion exponent as a function of the determined brightness information; transforming the first luminance components into second luminance components, including calculating an intermediate luminance value by applying the calculated expansion exponent to the first luminance component value and multiplying the intermediate value by the length of the second interval.

Abstract: The invention relates to a method and device for quantising the floating value of a pixel of an image by rounding either to a lesser whole number, to a greater whole number, or to the whole number closest to this floating value. The method is characterised in that the selection of rounding this floating value is determined based on a test value.

Abstract: A method for digitally generating a hologram plane from a three-dimensional scene, cut into a plurality of planes parallel to the hologram plane. The method includes for a current plane: counting a number of points of the non-zero amplitude scene; choosing a first or second technique for propagating a light wave emitted by the current plane as a function of a number of points of non-zero amplitude included in the current plane and with a preset threshold value, the first, point-based technique calculating the propagation of a sum of light waves emitted by point sources constituted by the points of the scene portion of a non-zero amplitude of the current plane on a following plane, and the second, field-based technique, globally calculating a light wave emitted by the scene portion situated in the current plane on a given plane; and processing the current plane according to the chosen propagation technique.

Abstract: The invention relates to a method for selecting an image dynamic range conversion operator from among a set of image dynamic range conversion operators by optimizing a quality criterion, each image dynamic range conversion operator being applied to an original image to obtain an image, called the modified image, whose dynamic range is lower than that of the original image, wherein said quality criterion is calculated, for each image dynamic range conversion operator, as a function of a distortion calculated from a reconstructed version after coding and decoding the original image modified by said image dynamic range conversion operator.

Abstract: A method and device for processing LDR images of a video sequence to improve image quality. The method comprises temporally decomposing successive HDR frames of a video sequence and the corresponding LDR frames and performing a comparison between the HDR and LDR frequency sub-bands. A current LDR image can then be modified on the basis of a comparison between the frequency sub-bands.

Abstract: The invention relates to a method and device for quantising the floating value of a pixel of an image by rounding either to a lesser whole number, to a greater whole number, or to the whole number closest to this floating value. The method is characterised in that the selection of rounding this floating value is determined based on a test value.

Abstract: The present invention generally relates to a method and device for tone-mapping a video sequence in which a local tone-mapping operator is applied on each frame of the video sequence to be tone-mapped. The method is characterized in that the spatial neighborhoods used by said local-tone-mapping operator are determined on a temporal-filtered version of the frame to be tone-mapped.

Abstract: The invention relates to a method for selecting an image dynamic range conversion operator from among a set of image dynamic range conversion operators by optimising a quality criterion, each image dynamic range conversion operator being applied to an original image to obtain an image, called the modified image, whose dynamic range is lower than that of the original image, wherein said quality criterion is calculated, for each image dynamic range conversion operator, as a function of a distortion calculated from a reconstructed version after coding and decoding the original image modified by said image dynamic range conversion operator.

Abstract: A method and apparatus for dynamic range expansion of an LDR video sequence are suggested. The suggested method comprises the steps of: acquiring the LDR video sequence and at least one HDR panoramas concurrently, an image in said HDR encompassing a wider field of view than an image in said LDR; determining a dynamic range expansion operator based on the LDR video sequence and the HDR panoramas; and applying the determined dynamic range expansion operator on the LDR video sequence.