Abstract: A method and an arrangement for processing data in a digital input image include a decoder configured to decode encoded data. A detector is configured to detect the decoded data and a correction device is configured to correct the detected data. A predicted maximum frequency is calculated based on first and second data sets transformed by first and second transform, respectively. A real maximum frequency is calculated based on data transformed by an overall transform of a data set corresponding to the concatenation of the first and second data sets. A grid is determined by comparing the real and predicted maximum frequencies for a portion of the digital input image.

Abstract: The present invention relates to a method of post-processing pixels contained in a sequence of digital images. Said method comprises a step (200) of detecting pixels belonging to natural contours (20) inside an image. It also comprises a step (210) of detecting an investigation zone (21) corresponding to a coding block. It comprises a filtering decision step (220) such that a current pixel is filtered if it has not been detected as being a natural contour pixel (20) and if it belongs to an investigation zone (21) containing at least one natural contour pixel (20). Finally, the method comprises a pixel filtering step (230), of the median filtering type, for the pixels to be filtered.

Abstract: The present invention relates to a device for processing blocks of coded data included in a sequence of coded digital images (ES) according to a block-based coding technique, said device comprising a post-processing circuit DFD (33). Such a device effectively corrects the blocking artifacts while minimizing the bandwidth used, the decoder directly transmitting decoded data blocks (B) to the post-processing circuit. In addition, such a device introduces no or little drift during the decoding since the decoder continues to use reference images (RB) during a motion compensation step. This is because the reference images are no longer the decoded images but the completely processed images as the post-processing circuit is situated in the decoding loop.

Abstract: The present invention concerns a method of detecting blocking artifacts (10) from video data coded and then decoded according to a block coding technique. Said method comprises the steps of calculating a first discrete transformation (1) of a first video data segment (11), calculating a second discrete transformation (2) of a second video data segment (12), said second segment being adjacent to the first segment, and calculating a discrete transformation (4) of a concatenated video data segment (13) corresponding to the concatenation (3) of the first and second segments. It also comprises a step of calculating (5) a blocking artifact level (17) from the content of the first and segments of transformed video data (14, 15), and the concatenated segment of transformed video data (16). In this way a very precise blocking artifact detection method is obtained, able to be used in a post-processing or coding of the video data.

Abstract: The present invention relates to a device for processing blocks of coded data included in a sequence of coded digital images (ES) according to a block-based coding technique, said device comprising a post-processing circuit DFD (33). Such a device effectively corrects the blocking artifacts while minimizing the bandwidth used, the decoder directly transmitting decoded data blocks (B) to the post-processing circuit. In addition, such a device introduces no or little drift during the decoding since the decoder continues to use reference images (RB) during a motion compensation step. This is because the reference images are no longer the decoded images but the completely processed images as the post-processing circuit is situated in the decoding loop.

Abstract: The present invention relates to a method of and an arrangement for processing data comprised in a digital input image. Said arrangement comprises a decoder unit (20) intended for transmitting a decoded analog image (S2) to a television receiver (27) via a channel CH (23). The decoder unit includes a device MPD (21) by means of which the encoded digital image (S1) can be decoded and a digital to analog converter DAC (22). The television receiver includes an analog to digital converter ADC (24) intended for supplying a digital input image (S3) to a device DET (25) by means of which it is possible to detect if said digital input image has been encoded in accordance with a block-based encoding technique. A correction or post-processing device COR (26), whose operation depends on the data supplied by the detection device, thus enables the display quality of the digital image to be improved in view of its display on the screen.

Abstract: The present invention relates to a method of processing a digital input signal that comprises at least the steps of low pass filtering (FIL) the input signal (IS), which results in a filtered signal (FS) comprising filtered samples; determining (DET) a correction area (CA) around block boundaries; correcting (COR) by adding a random binary number (RN) comprising at least one bit to the filtered samples belonging to the correction area, which results in an output signal (OS).