Abstract: The disclosure relates to a method for processing the noise of a stream comprising a series of images, comprising spatial filtering of a current image In in order to obtain a spatially filtered image Sn; determining a motion vector for each block B of pixels of the image Sn, from a single image Sn-1; calculating a confidence index ?n[B] for each block B of image In, from the motion vector determined for B; constructing a temporal filter from the calculated confidence indices ?n[B] and applying the temporal filter to the current image In in order to obtain a temporally filtered image Tn; spatial filtering of the current image In in order to obtain a spatially filtered image Dn where Dn can be equal to Sn, and obtaining a temporally and spatially filtered image Rn by applying a function combining image Tn and image Dn.

Abstract: Disclosed is a method for processing a video stream including a set of images liable to contain a transition effect, the method including the following steps: detecting a fade-type transition effect within the set of images of the video stream and, where appropriate, calculating minimum and maximum brightnesses LMIN and LMAX for each image of the set of images containing the fade; estimating minimum and maximum brightnesses EMIN and EMAX for all of the images not containing the detected transition effect; determining minimum and maximum brightnesses SMIN and SMAX for a standard dynamic range; calculating minimum and maximum brightnesses TMIN and TMAX depending on the minimum and maximum brightnesses LMIN, LMAX, EMIN, EMAX, SMIN and SMAX calculated and determined beforehand; transmitting the calculated minimum and maximum brightnesses TMIN and TMAX with a view to dynamic range compression.

Abstract: To encode an image divided into blocks of a set of images, each block being encoded according to one of a plurality of encoding modes including at least one temporal correlation prediction encoding mode utilizing a plurality of images, a motion estimation vector search area is defined in a second image of the set of images, distinct from the first image and previously encoded according to a predefined sequence of encoding images of the set of images, a portion at least of the search area having substantially the shape of an ovoid, the data from the search area is stored in a cache memory, a motion estimation vector of the current block is determined by a search in the search area in the cache memory, and the motion estimation vector is used to decide the encoding of the current block according to the one of the plurality of encoding modes.

Abstract: A method for processing a video stream prior to encoding, the video stream potentially comprising a film grain, the method comprising: measuring a film grain intensity in the video stream; obtaining at least one encoding rate information item associated with the video stream, in order to determine a pair of respective values for the grain intensity and encoding rate; comparing the pair values with predetermined respective threshold values in order to categorize the video stream with respect to pairs of predetermined values of grain intensity and rate; and selecting a film grain management strategy among at least four combinations based on the categorization of the video stream.

Abstract: Disclosed is a method for analyzing a set of images of a video sequence with a view to performing a processing of the sequence. The method includes: determining, in the video sequence, a plurality of disjointed consecutive sub-sequences of at least one successive image according to the type of processing to be carried out and according to the content of the video sequence; and analyzing the images of each sub-sequence determined in the video sequence.

Abstract: Disclosed is a method for processing noise in a digital image having multiple image portions, including: (a) Predefining: criteria of interest for denoising selected details of any image portion of the digital image; a plurality of possible processing procedures to be applied to an image portion in order to denoise the selected details, each processing procedure having an efficiency related to an associated complexity level, the possible processing procedures being ordered by increasing complexity level; (b) For each portion of the image: analyzing the image portion to quantify the presence of one or more of the selected details in the image portion, and calculating an overall interest of the image portion as a function of respective quantifications of the presences of the selected details; comparing the overall interest at the complexity levels, in order to launch the processing procedure having the complexity level corresponding to the calculated overall interest.

Abstract: Disclosed is a method for encoding a first image in a set of images, in which the first image is cut into blocks, each block being encoded according to one from a plurality of encoding modes including at least one temporal correlation prediction encoding mode using a plurality of images from the set of images. The method includes, for a current block of the first image: determining a first motion estimation vector of the current block, determining a value of a visual distortion metric for a temporal correlation prediction encoding mode, the visual distortion metric using a distance between a first temporal prediction vector of the current block pointing to the second image and the first motion estimation vector of the current block, and using the value of the visual distortion metric to encode the current block.

Abstract: The invention relates to a method and a device for regulating the encoding bit rate of video images relative to a target image size). The images being subdivided into zones to be encoded, the complexity of encoding of each zone is distinguished among the zones, the zones to be encoded are classified according to a determined order of complexity, each zone is successively encoded according to the decreasing order of complexity, successively minimizing the estimated encoding error of each zone, the final size of each image relative to the target size and the bit rate of the sequence of video images. Application to the video encoding of images of video sequences, in particular to networked video surveillance.

Abstract: The invention relates to a method and a device for regulating the encoding bit rate of video images relative to a target image size. The images being subdivided into zones to be encoded, the complexity of encoding of each zone is distinguished among the zones, the zones to be encoded are classified according to a determined order of complexity, each zone is successively encoded according to the decreasing order of complexity, successively minimizing the estimated encoding error of each zone, the final size of each image relative to the target size and the bit rate of the sequence of video images. Application to the video encoding of images of video sequences, in particular to networked video surveillance.

Abstract: A CABAC-type encoding device for encoding an initial flow of binary digital information for generating an output flow for forming video images after decoding, includes: elements for analyzing successive sequences of bits of the initial binary flow, bit-by-bit, and for deducing, for each bit, an interval representing the occurrence probability associated with the bit, the interval being defined by the size thereof and the lower boundary thereof; elements for analyzing the interval and ensuring a renormalization thereof. The elements for ensuring the renormalization include: a reference table containing, for each possible value of the lower boundary and the size, sequences of bits to be inserted into the output flow, and the number of unknown bits waiting to be inserted for this specific renormalization step; and elements for determining the address of the data, in this reference table.

Abstract: An encoding device and method, of CABAC type, for an initial stream of binary digital information intended to generate an outgoing stream to form video images, after decoding, the method included the following steps: bit-by-bit analysis of the successive series of bits of the initial binary stream so as to deduce therefrom, for each bit, an interval representing the probability of occurrence associated with this bit, this interval being defined by its size CIR and its lower bound CIL, analysis of this interval so as to ensure, if necessary, a renormalization thereof. The renormalization is non-iterative and for each bit of the initial stream is compliant with the appended figure in which: M is the length of the sequence S of high-order bits common to CIL and CIR, N is the integer number such that CIR.2N-1<0.25?CIR.2N, BO is the number of bits waiting to be inserted.

Abstract: A CABAC-type encoding device for encoding an initial flow of binary digital information for generating an output flow for forming video images after decoding, includes: elements for analyzing successive sequences of bits of the initial binary flow, bit-by-bit, and for deducing, for each bit, an interval representing the occurrence probability associated with the bit, the interval being defined by the size thereof and the lower boundary thereof; elements for analyzing the interval and ensuring a renormalization thereof. The elements for ensuring the renormalization include: a reference table containing, for each possible value of the lower boundary and the size, sequences of bits to be inserted into the output flow, and the number of unknown bits waiting to be inserted for this specific renormalization step; and elements for determining the address of the data, in this reference table.