Abstract: A method for determining a distance offset between a depth map of an indirect time-of-flight measurement device and a reference ground truth map includes emitting emission optical radiation by an emission circuit of the indirect time-of-flight measurement device. The emission optical radiation is sequentially modulating by N modulation frequencies. N is greater than or equal to three. The method further includes receiving, by a reception circuit of the indirect time-of-flight measurement device, reception optical radiation generated by the emission optical radiation reflected off objects of a scene and by optical crosstalk between the emission optical radiation and the reception optical radiation, and estimating the distance offset based on the reception optical radiation.

Abstract: Methods of processing a frame in a video sequence of digital images are provided. The methods include determining a global motion vector for the frame relative to a previous frame in the sequence, deriving a jitter function from the global motion vector, the jitter function including an estimate of undesired motion of the frame relative to the previous frame, and determining whether the frame is blurred above a first predetermined threshold. If the frame is blurred above the first predetermined threshold, stabilizing the frame using the jitter function and applying a deblur function to the frame.

Abstract: An image sequence comprises at least a first image and a second image. A motion vector (MV(1)) is associated to these first and second images and is defined in a coordinate system having at least a first direction and a second direction, the second direction being different from said first direction. This motion vector has a first previous component value (MVD1(0)) in the first direction. A method processes both images in order to determine an estimate of the motion vector based on the first previous component value. To this purpose, the method defines a first image portion in the first image and a second image portion in the second image based on the first previous component value of the motion vector. Then, the method determines a first characteristics vector for the first image in the first image portion and a second characteristics vector for the second image in the second image portion.

Abstract: The invention relates to a method for estimating a blurriness value based on a series of at least two frames acquired within a period of time greater than or equal to a given exposure time, the frames being grouped in at least one couple of frames, characterized in that it comprises determining, for each couple of frames of the series, first and second values corresponding to a displacement according to a first direction and a second direction, between the first frame and the second frame of a couple of frames, determining a first blur measure for one direction among the first and second directions by calculating a metric based on the displacement values for each couple of frames of at least a subset of the series, determining a second blur measure for the other direction among the first and second directions by calculating a metric applied to the displacement values for each couple of frames of the series of frames and determining a blurriness value based on the first and second blur measures.

Abstract: Methods of processing a frame in a video sequence of digital images are described, the methods comprising: determining a global motion vector for the frame relative to a previous frame in the sequence; deriving a jitter function from the global motion vector, the jitter function comprising an estimate of undesired motion of the frame relative to the previous frame; determining whether the frame is blurred above a first predetermined threshold; and if so, stabilising the frame using the jitter function and applying a deblur function to the frame.

Abstract: The invention particularly relates to a method for identifying an image acquisition feature of a digital image oriented in a coordinate system having a reference axis. According to the invention, this method comprises the steps of: (A) detecting the contours of each distinctive element of the image; -(B) forming a list including each contour constituted by a rectilinear segment; (C) searching, in the list of rectilinear contours, a pair of significant rectilinear segments; (D) in the case where step (C) is successful, checking for a condition of relative symmetry of the significant rectilinear segments with respect to the reference axis; and (E) producing, respectively in the case where step (D) is successful and in the case where one of steps (C) and (D) fails, a data respectively representative of the presence and absence of perspective in the image acquisition, with respect to the reference axis.

Abstract: The invention relates to a method for estimating a blurriness value based on a series of at least two frames acquired within a period of time greater than or equal to a given exposure time, the frames being grouped in at least one couple of frames, characterized in that it comprises determining, for each couple of frames of the series, first and second values corresponding to a displacement according to a first direction and a second direction, between the first frame and the second frame of a couple of frames, determining a first blur measure for one direction among the first and second directions by calculating a metric based on the displacement values for each couple of frames of at least a subset of the series, determining a second blur measure for the other direction among the first and second directions by calculating a metric applied to the displacement values for each couple of frames of the series of frames and determining a blurriness value based on the first and second blur measures.

Abstract: An image sequence comprises at least a first image and a second image. A motion vector (MV(1)) is associated to these first and second images and is defined in a coordinate system having at least a first direction and a second direction, the second direction being different from said first direction. This motion vector has a first previous component value (MVD1(0)) in the first direction. A method processes both images in order to determine an estimate of the motion vector based on the first previous component value. To this purpose, the method defines a first image portion in the first image and a second image portion in the second image based on the first previous component value of the motion vector. Then, the method determines a first characteristics vector for the first image in the first image portion and a second characteristics vector for the second image in the second image portion.

Abstract: The invention particularly relates to a method for identifying an image acquisition feature of a digital image oriented in a coordinate system having a reference axis. According to the invention, this method comprises the steps of: (A) detecting the contours of each distinctive element of the image;-(B) forming a list including each contour constituted by a rectilinear segment; (C) searching, in the list of rectilinear contours, a pair of significant rectilinear segments; (D) in the case where step (C) is successful, checking for a condition of relative symmetry of the significant rectilinear segments with respect to the reference axis; and (E) producing, respectively in the case where step (D) is successful and in the case where one of steps (C) and (D) fails, a data respectively representative of the presence and absence of perspective in the image acquisition, with respect to the reference axis.

Abstract: A method of restoring a digital image, the method comprising partitioning the image into a plurality of blocks of pixels, processing each block to produce a restored block and concatenating the restored blocks to produce a restored digital image, wherein the step of processing each block comprises: i) padding the block with additional pixels having values extrapolated from a range of pixel values across the block to produce a padded block; si) performing a Fourier transform operation on the padded block to produce a transformed block; iii) applying an inverse blur filler to the transformed padded block to produce a filtered block; and Iv) performing an inverse Fourier transform on the filtered block to obtain the restored block.

Abstract: According to one example embodiment, a communication system includes a transmitter and a receiver for receiving symbols from a phase-shift shift keying modulation. The system also includes estimation means for estimating a frequency error relating to a symbol based on a sequence of symbol phases. The receiver includes calculation means for calculating a phase sequence, called an initial sequence, based on decisions made on symbols. The receiver also includes means for detecting and correcting phase jumps in this initial sequence in order to supply a phase sequence, called a final sequence, to the frequency error estimation means.

Abstract: A video processor processes an image that comprises block of pixels. The video processor comprises a sharpness enhancer (ENH). The sharpness enhancer establishes an output pixel (Yo) on the basis of various input pixels (Yi) within an adaptive filter window. The adaptive filter window exclusively comprises input pixels that form part of the same block of pixels.

Abstract: The invention relates to digital transmissions. It particularly relates to a new transmission system (DVB-S2), which is backward compatible with a primary transmission system (DVB-S), enabling a receiver of the primary system to receive signals transmitted by a transmitter of the new transmission system. The principle of the invention is based on using a hybrid QPSK/Non-Uniform 8-PSK modulation. The hybrid modulation is specified by a periodic binary pattern indicating, for each symbol, which modulation is used.

Abstract: The invention relates to digital transmissions. It particularly relates to a method of transmitting data from a transmitter to a receiver using multi-carrier Code Division Multiple Access (CDMA) for accessing a transmission system. The transmitted data are OFDM modulated using Orthogonal Frequency Division Multiplexing (OFDM) after being spread with a set of predefined spreading sequences of consecutive chips, wherein two successive chips of the predefined sequences are transmitted on non-successive carriers and in non-successive time intervals.

Abstract: The invention relates to digital transmission and recording systems. It particularly relates to a receiver for receiving a sequence of encoded data produced by a data source from an information sequence and encoded by an encoder, the received encoded data sequence possibly comprising errors, the receiver comprising decoding means for retrieving the information sequence from the received encoded data sequence.

Abstract: The invention relates to digital transmissions. It particularly relates to a new transmission system (DVB-S2), which is backward compatible with a primary transmission system (DVB-S), enabling a receiver of the primary system to receive signals transmitted by a transmitter of the new transmission system. The principle of the invention is based on using a hybrid QPSK/Non-Uniform 8-PSK modulation. The hybrid modulation is specified by a periodic binary pattern indicating, for each symbol, which modulation is used.

Abstract: A digital transmission system utilizing data coding at the transmitter and data decoding at the receiver, the decoding being iterative, reliability data about soft decisions being calculated for each iteration. The last iteration results in a hard decision. Soft decisions are transformed so as to normalize the mean value of the reliability data, using evolutive weighting of the soft decisions with the received data. The coding is preferably a product code concatenated with a block code such as, for example, a Reed Solomon code. Such coding is well suited to upstream transmission in an interactive satellite communication system.

Abstract: A transmission system having a channel subjected to fading uses an iterative block detection method which includes a multiplication step for multiplying the received blocks via a filter matrix whose elements are written as ρ j * E ⁢   ⁢ ( ρ j 2 ) + N 0 where &rgr;j*, j=1, . . . , n are the conjugate values of the coefficients &rgr;j of the channel, n is the size of the block, E(&rgr;j2) is the expectation &rgr;j2, and No is the variance of the Gaussian noise.

Abstract: The invention proposes an efficient method of determining, in an arbitrary assembly of non-uniformly distributed points, the point which is nearest from a characteristic of a given analog signal. It is particularly applicable to the detection of symbols in a PCM modem. The method comprises the step of considering successive search intervals, each search interval being obtained by splitting up a preceding search interval into two intervals, each interval comprising a number of points, the numbers being equal or different by one, such that one of these two intervals which comprises the received point constitutes the next search interval.

Abstract: The invention relates to an encoding/decoding method associating the modulation/demodulation with the channel encoding/decoding operation so as to improve the performances at the decoding level in the case of a modulation having a large number of states. The iterative decoding method involves a pair of SISO decoders receiving, at their inputs, probability information components for symbols so as to supply, at the output, a posteriori probability information components for the transmitted information symbols. Application: Digital telecommunication.