Abstract: Method of evaluating a defect of quality in a data signal, associated device and computer program. The method evaluates the defect of a carrier signal bearing data intended to be restored to a recipient, the signal including a video component and audio component. The method includes the following steps implemented on at least one sample of the signal: detection of a defect in the video component of the sample and calculation of a duration associated with the defect; assigning a class of defect to the defect detected as a function of its associated duration; according to the class of defect assigned, obtaining a result of searching for a defect in the audio component at the instants corresponding to the sample; deciding to confirm the detection of a defect of quality in the sequence as a function of the result of the search for a defect in the audio component.

Abstract: Method of evaluating a defect of quality in a data signal, associated device and computer program. The method evaluates the defect of a carrier signal bearing data intended to be restored to a recipient, the signal including a video component and audio component. The method includes the following steps implemented on at least one sample of the signal: detection of a defect in the video component of the sample and calculation of a duration associated with the defect; assigning a class of defect to the defect detected as a function of its associated duration; according to the class of defect assigned, obtaining a result of searching for a defect in the audio component at the instants corresponding to the sample; deciding to confirm the detection of a defect of quality in the sequence as a function of the result of the search for a defect in the audio component.

Abstract: Method of evaluating a defect of quality in a data signal, associated device and computer program. The method evaluates the defect of a carrier signal bearing data intended to be restored to a recipient, the signal including a video component and audio component. The method includes the following steps implemented on at least one sample of the signal: detection of a defect in the video component of the sample and calculation of a duration associated with the defect; assigning a class of defect to the defect detected as a function of its associated duration; according to the class of defect assigned, obtaining a result of searching for a defect in the audio component at the instants corresponding to the sample; deciding to confirm the detection of a defect of quality in the sequence as a function of the result of the search for a defect in the audio component.

Abstract: A method and apparatus are provided for evaluating a quality, as perceived by a recipient, of a signal carrying a stimulus. The method includes a step for detecting absences of variation of said signal and a step of quantifying at least one deterioration corresponding to an absence of variation. The quantity of deterioration computed during the quantification step depends on an amplitude of variation of the stimulus immediately following the concerned absence of variation. The method and apparatus enable the correlation of the duration of variance, possible past of invariances and a sudden variation of amplitude following said in variance, in implementing an automatic technique in real time, for example.

Abstract: A method and apparatus are provided for evaluating a quality, as perceived by a recipient, of a signal carrying a stimulus. The method includes a step for detecting absences of variation of said signal and a step of quantifying at least one deterioration corresponding to an absence of variation. The quantity of deterioration computed during the quantification step depends on an amplitude of variation of the stimulus immediately following the concerned absence of variation. The method and apparatus enable the correlation of the duration of variance, possible past of invariances and a sudden variation of amplitude following said in variance, in implementing an automatic technique in real time, for example.

Abstract: A method and device for monitoring the quality of distributed digital images coded by blocks of pixels in which a false contour phenomenon may be generated when the image is reproduced. An image average for pixels represented by at least one luminance respectively chrominance components is calculated and a false contour effect on the basis of a criterion for discriminating the luminance or chrominance component difference between adjacent pixels of adjacent groups of pixels is detected in at least one reference direction of each current image. A visibility coefficient of at least one current image is calculated from the value of the image average speed vector and psycho-visual criteria relating to the existence of the false contour effect in the reference direction.

Abstract: A method and device for monitoring the quality of distributed digital images coded by blocks of pixels in which a false contour phenomenon may be generated when the image is reproduced. An image average for pixels represented by at least one luminance respectively chrominance components is calculated and a false contour effect on the basis of a criterion for discriminating the luminance or chrominance component difference between adjacent pixels of adjacent groups of pixels is detected in at least one reference direction of each current image. A visibility coefficient of at least one current image is calculated from the value of the image average speed vector and psycho-visual criteria relating to the existence of the false contour effect in the reference direction.