Abstract: Method and apparatus for the digital encoding of a first raw file, the method includes: a first step of capturing the raw file, the raw file being an audio and/or image and/or video file; a second step of encoding the captured raw file into a second file, in a proprietary format (P); then, a third step for re-encoding the second file into a third file in a compatible format (C).

Abstract: A Method for reducing the entropy of an original matrix, includes a step using a wavelet transformation of the original matrix into a transformed matrix, a quantisation coefficient corresponding to each wavelet level, the wavelet transformation being calculated in fixed point using a first number of digits at least equal to 1, for example 3 digits, after the point. Such a method is particularly advantageous for image compression.

Abstract: Method for encoding a series of symbols using several models of the arithmetic or range coder type and including steps where: each model is associated with a belonging criterion, the series is run through in order to determine, for each symbol, the encoding model to which it belongs, according to the criteria; then a probability of occurrence of each symbol in the corresponding model is determined; then the series is run through by encoding each symbol successively; and a file is formed from the code thus obtained.

Abstract: Method and apparatus for the digital encoding of a first raw file, the method includes: a first step of capturing the raw file, the raw file being an audio and/or image and/or video file; a second step of encoding the captured raw file into a second file, in a proprietary format (P); then, a third step for re-encoding the second file into a third file in a compatible format (C).

Abstract: A method for reversible coding of an image, including extracting compression information from an image compressed in an original format, at least partly decompressing the compressed image into an intermediate at least partly decompressed image, re-encoding the intermediate image into a re-encoded image, and preferably associating in a same file, the re-encoded image with compression information.

Abstract: A method for compressing a stream by means of a codec (C), provided for assigning to a compressed stream an encoding throughput (Q) measured in bits per second, using a pre-filter (X1) replacing in the header (T1) of the original stream, the restoration frequency (R) with a frequency equal to the product (R×K) of the restoration frequency (R) by a coefficient (K) and then for retransmitting the thereby filtered stream (FX1) to the codec; the post-filter (X2) replacing the restoration frequency (R) into the header (TX2) of a stream (FX2) resulting from the encoding of the pre-filtered stream (FX1) by the codec C.

Abstract: A method is disclosed for compressing a sequence of initial digital values into a compressed sequence of compressed values, intending to restore these values into a decompressed sequence of decompressed values. For a first initial value of the sequence, the compressed value of the first initial value is equal to the first initial value and the decompressed value of the compressed value of the first initial value is equal to the first initial value.

Abstract: A method for compressing a stream by means of a codec (C), provided for assigning to a compressed stream an encoding throughput (Q) measured in bits per second, using a pre-filter (X1) replacing in the header (T1) of the original stream, the restoration frequency (R) with a frequency equal to the product (R×K) of the restoration frequency (R) by a coefficient (K) and then for retransmitting the thereby filtered stream (FX1) to the codec; the post-filter (X2) replacing the restoration frequency (R) into the header (TX2) of a stream (FX2) resulting from the encoding of the pre-filtered stream (FX1) by the codec C.

Abstract: A method for differential compression of a sequence of digital values adapted to avoid error propagation during restoration of the values.

Abstract: A method for processing a digital file of the images, video and/or audio type which comprises a phase for putting into line per color layer and/or per audio channel, digital data of any audio, image and video file, a compression phase using algorithm in which each compressed value VCn of position N is obtained by subtracting from the value Vn of same position N of the original file, a predetermined number of successive compressed values (VCn-1, VCn-2, . . . ) calculated previously, and a restoration phase using an algorithm in which each restored value VDn of position N is obtained by adding to the value VCn, of the same position of the compressed file, a predetermined number of successive compressed values (VCn-1, VCn-2, . . . ).

Abstract: The invention concerns a method comprising a coding step consisting in replacing the original values of the file with coding values of reduced brightness, a common coding value being attributed to a group of original values, a step of restitution consisting in setting correspondence values between the coding value and the restored value, selected from one of the values of the corresponding group, an insertion step consisting in modifying the successive redundant restored values so as to produce shades and a step which consists in reading the values resulting from the insertion step.

Abstract: A method for processing a digital file of the images, video and/or audio type which comprises a phase for putting into line per color layer and/or per audio channel, digital data of any audio, image and video file, a compression phase using algorithm in which each compressed value VCn of position N is obtained by subtracting from the value Vn of same position N of the original file, a predetermined number of successive compressed values (VCn-1, VCn-2, . . . ) calculated previously, and a restoration phase using an algorithm in which each restored value VDn of position N is obtained by adding to the value VCn, of the same position of the compressed file, a predetermined number of successive compressed values (VCn-1, VCn-2, . . . ).