Abstract: A lossless encoding methodology is described based on residual coding techniques and using a modified Least Mean Squares methodology to develop a predictor for a signal to be encoded, and a residual as the difference between the signal and its predicted value. After the residual for an input signal segment is obtained according to the method of the invention, that method is again applied to the residual value process to develop a second predictor, from which a second residual value is obtained. The method is then applied for at least one further iteration to the most recently obtained residual value process to develop a third predictor for the signal to be encoded. A single prediction value is then selected as a statistical representative of those multiple predictor values. The residual value to be used for encoding the input signal increment is determined as the difference between the signal value and the selected predictor value.

Abstract: Method and signal processing apparatus for reducing the number of bits of a digital input signal (Mi) comprising the steps of adding a pseudo-random noise signal (Na) to the digital input signal (Mi) to obtain an intermediate signal (Di), the pseudo-random noise signal (Na) being defined by noise parameters (Np), and quantizing the intermediate signal (Di) having a word length of n bits to a reduced word length signal (Me) having a word length of m bits, n being larger than or equal to m. The method further comprises the step of quantizing the intermediate signal (Di) comprises a first transfer function which is non-linear, the first transfer function being defined by non-linear device parameters (NLDp). Also, the present invention relates to a method and signal decoding apparatus for recovering an output signal (Mo) from a reduced word length signal (Me) provided by the method according to the invention.

Abstract: A method of modifying a group of pictures (GOP) structure in an MPEG video signal from a low-delay mode bitstream having I and P pictures to a non-low-delay bitstream having I, P and B pictures uses the motion vectors from the low-delay mode bitstream to derive the motion vectors for the non-low-delay mode bitstream. Motion vectors for anchor pictures for the non-low-delay mode bitstream are converted from the motion vectors for the corresponding pictures in the low-delay mode bitstream. Motion vectors for the B pictures in the non-low-delay mode bitstream are converted from the motion vectors for the corresponding P pictures in the low-delay mode bitstream. The converted motion vectors for the non-low-delay mode bitstream are used in recoding an uncompressed video signal derived from the low-delay mode bitstream to produce the non-low-delay mode bitstream.

Abstract: A data stream (DS) comprises a time multiplex of coded data (D) and control data (C). The data stream (DS) may be, for example, of the MPEG type representing a sequence of pictures. The coded data (D) is transcoded (T) so as to obtain transcoded data (DT) which differs in size from the coded data (D). The control data (C) is adapted for the transcoded data (DT) so as to obtain adapted control data (CA) which does not substantially differ in size from the control data (C). The transcoded data (DT) and the adapted control data (CA) are written into a transcoder output buffer (TOB) and read from the transcoder output buffer (TOB) so as to obtain a transcoded data stream (DST). This allows an efficient use of a transmission channel via which the transcoded data stream (DST) is to be transmitted and, consequently, it allows a satisfactory transcoding quality.

Abstract: A device having alternative intercommunication formats, and an automated method of selecting the appropriate format to use, in dependence upon the ability of the device to which it is interconnected to utilize this format. Many devices utilize standard analog formats, such as NTSC, PAL, SECAM, and others, to communicate with other devices; many of these devices utilize digital formats, such as MPEG and others, for internal processing or storage. By appending a supplemental signal to the analog signal, the ability of the device to use a digital format can be communicated to the device to which it is interconnected. By communicating their capabilities, devices which have the ability to utilize the same digital format can automatically switch to this digital format for intercommunication, thereby avoiding the signal degradations typically associated with conversions to and from an analog form.

Abstract: In the image decoding apparatus, the maximum absolute value of difference values of adjacent pixel data of each pixel block of image data is obtained as a feature of the image data. An optimum quantizing coefficient is selected for the maximum absolute value of the difference value. With the selected quantizing coefficient, the maximum absolute value is quantized. When the difference values of adjacent pixel data of each pixel block of image data concentrate in the vicinity of "0", they are quantized with a smaller quantizing coefficient. Thus, with an optimum quantizing coefficient, each pixel block of image data can be quantized. Consequently, quantizing errors can be reduced.

Abstract: A method of transmitting a voice communications signal includes the steps of sampling the signal and creating digital representations of the samples. The digital representations are speech-coded to create speech-coded data which is converted to analog symbols. A carrier in the 46-49 MHz band is modulated by the analog symbols and transmitted. A method of receiving a voice communications signal includes the steps of receiving a modulated carrier in the 46-49 MHz band and demodulating the modulated carrier to recover analog symbols. The analog symbols are converted to digital samples, which are then converted to speech-coded data. The speech-coded data are decoded to produce digitized samples, which are converted to analog samples and filtered to produce the voice communications signal. A cordless telephone system according to the invention includes a handset and a base unit.

Abstract: An improvement to a half duplex multipoint communication environment wherein a pilot tone enables a control device to maintain synchronization with a plurality of remote devices. The present invention employs a quantization noise compensator apparatus and method to supply a single bit, two level analog signal to drive a Voltage Controlled Crystal Oscillator (VCXO) in a remote device. The VCXO derives the sample rate signal for both transmit and receive devices, eliminating the requirement for a highly accurate digital to analog converter, thus reducing the cost and complexity of the system while allowing continuous synchronization between a control device and a plurality of remote devices.

Abstract: The quality of service provided by a connection in transferring data units (19) between first and second points (A, B) across a network (10), is measured by a method involving monitoring the normal connection traffic at the first and second points (A, B) to detect the occurrence of the same events at each point (unit 22). An event is deemed to have occurred at a monitored network point when a predetermined set of criteria concerning one or more data units is satisfied by the connection data-unit traffic at the point concerned. Whenever an event is detected, an event report or "digest" is generated (unit 25), this digest including a signature based on the contents of the data units giving rise to the event. Digests from both monitored network points (A, B) are sent to a correlation unit (30) where digests relating to the occurrence of the same event at the two network points are matched up. The matched digest pairs are then passed to a measurement unit (31) to derive quality of service measurements.

Abstract: A maximum a posteriori (MAP) filter is applied as a loop filter during encode/decode processing to generate filtered data used to encode/decode other data. In one embodiment, the MAP filter is applied iteratively to a decoded frame to generate the resulting filtered frame. When applied as a loop filter, the filtered frame is used to generate reference data used to encode or decode one or more other video frames.

Abstract: The coding or decoding of video data with the associated audio and/or other data can be performed, for example, on the basis of the standards ISO/IEC 11172 (MPEG1) or ISO/IEC 13818 (MPEG2). Such coding and decoding can include the conversion of a primary bit stream coded on the basis of such standards into a secondary bit stream with a different data rate. Since the information content of the motion vectors from the primary bit stream retain their validity in the secondary bit stream, it is not necessary to recalculate motion vectors for transcoding. Instead, encoding of the secondary bit stream is performed with the aid of the motion vectors from the primary bit stream which are reused. In such a case, the encoding of the secondary bit stream is carried out in a restricted prediction mode, i.e. only those prediction modes which are described by respective block type or the motion information of the primary bit stream are allowed in the secondary bit stream.

Abstract: An IF sampling receiver for use in a wireless communication system includes first and second channels, with one channel generating an in-phase (I) component of an incoming analog IF signal, and the other channel generating a quadrature (Q) component of the analog IF signal. Each of the two channels of the IF sampling receiver includes a corresponding sigma-delta modulator channel. Each of the two sigma-delta modulator channels may be separated into m parallel branches by applying a polyphase decomposition technique to one or more resonators associated with the sigma-delta modulator. The invention thus provides a general framework for configuring a given channel of a sigma-delta modulator to include m parallel branches. The invention also provides a technique for separating a given sigma-delta modulator into n parallel channels, where n is greater than 2. Each of the n parallel channels may then be separated into m parallel branches.

Abstract: A subtraction device subtracts a predicted value generated by a predicting portion from a digital picture signal supplied through an input terminal. The subtraction device generates a difference signal as an output signal. A quantizing portion detects an activity of the difference signal, designates the number of quantizing steps corresponding to the activity, and quantizes the difference signal with the number of quantizing steps. The quantizing portion outputs side information to an output terminal.

Abstract: An adder 101 computes the difference between the activity (act) of an objective block and the average value (avg(act)) of activities all over the previous frame. A shifter 102 shifts the difference by a specified bits (n). Finally, an adder 103 adds output of the shifter 102 to a reference quantizing step (Qj) determined by a code quantity control and outputs the added result as a quantizing step Mquant of the objective block.

Abstract: Auxiliary data is carried substantially imperceptibly with video transform data in combined transform samples according to a visibility threshold. The auxiliary data provides a capability for a copy protect scheme or verification of television viewing activity. The video transform samples are extracted from a compressed packetized data stream and normalized if required. The auxiliary data modulates data carrier sequences such as pseudo-noise (PN) spread spectrum signals in different spatial frequencies to provide auxiliary data subband samples, which are in turn combined with the video transform samples in one or more spatial frequencies to provide combined subband samples. The auxiliary data subband samples may be also spectrally shaped according to the video transform samples to improve concealment. The combined transform samples are then multiplexed into the packetized data stream. Full decompression of the video transform samples is not required.

Abstract: The apparatus and method describes herein shows a system of digitizing analog or digital electronic or optical signals with very high single bit serial digital data streams which digitizing is suitable to automatically adapt the transmission of multiple types of analog and digital signals. The system is especially well suited for allowing the coupling and transmission of signals.

Abstract: Disclosed is a quantization/inverse quantization circuit including a differential pulse code modulator (DPCM). Video CODEC standards (i.e., JPEG, H.261, H.263, MPEG-1, and MPEG-2) include various functions for an image compression and an image reconstruction. The conventional quantization/inverse quantization circuit has been designed to be fit for only one desired standard, so that the quantization/inverse quantization circuit used for one standard cannot be directly used for another standard. Accordingly, in relation to a difference between standards and required function therebetween in order to use the present invention in all video CODEC standards, the present invention discloses a quantization/inverse quantization circuit which can support all modes (i.e., a quantization mode in coding, an inverse quantization mode in decoding, and a reconstruction mode) by employing one quantization circuit as a quantization/inverse quantization circuit which can be used in all video CODEC standards.

Abstract: A subtraction device subtracts a predicted value generated by a predicting portion from a digital picture signal supplied through an input terminal. The subtraction device generates a difference signal as an output signal. A quantizing portion detects an activity of the difference signal, designates the number of quantizing steps corresponding to the activity, and quantizes the difference signal with the number of quantizing steps. The quantizing portion outputs side information to an output terminal.

Abstract: A speech encoding communication system for use with a land mobile radio telephone system which decreases an unfamiliar feeling to a sound output caused by a cyclic tone variation of background noise. On the transmission side, an audition weighting filter selectively receives a sound signal or an output of a low-pass filter for the sound signal in response to VOX mode information. In a sound absent condition based on the VOX mode information, a power quantizer outputs a power index calculated by an average of the power over a long period, and an LPC analyzer outputs a unique value as an LPC and an LSP quantizer outputs a quantized LSP index and a quantized LPC obtained when the LPC has the unique value in the sound absent condition. Further, an adaptive codebook search unit controls an adaptive codebook index to a unique value without performing searching processing. On the reception side, a power controller receives a quantized power, VOX mode information and a sound signal.

Abstract: A waveform correction apparatus is disclosed. The waveform correction apparatus includes a signal generator for generating a signal; a maximal value recorder for recording a maximal value of the signal waveform; a minimal value recorder for recording a minimal value of the signal waveform; a difference value generator for generating a difference value of the maximal value and the minimal value; and a comparative controller for comparing the difference value with a reference value. The comparative controller outputs a corrected waveform when the difference value is larger than the reference value, otherwise it outputs the original waveform generated by the waveform generator. The corrected waveform is formed by shifting up or down the original waveform by a constant value.

Abstract: An input bitstream (a first bitstream) is divided into a main code having a changeable length and the remaining data. The main code is subjected to a bit-rate conversion and combined with the remainig data to output a second bitstream. By this arrangement, the configuration ofthe bit-rate conversion circuit can be simplified and delay in the conversion process can be reduced. Incidentally, the main code corresponds to the DCT-coefficient data(e) and the quantizer scale(d), while the remaining data corresponds to the header data(a), the handling type data(b) and the motion vector data(c) respectively.

Abstract: A method for encoding a 10-bit based picture using a circuitry or devices inherently designed for handing an 8-bit based picture. The 10-bit based input picture data is motion-compensated with 8 bits in a motion compensation circuit. From the motion-compensated picture data, representative value data and the quantization width are found by an in-bloc representative value calculation circuit and a block quantization width calculation circuit, respectively. A difference between the picture data and the representative value data is found by an adder. The difference is sent to a block quantizer where first 8-bit quantized data is generated on the basis of the quantization width so that the representative value is at a mid point of the quantization width. The first quantized data is transformed by a discrete cosine transform circuit of a difference signal encoder to generate transform coefficients which are quantized by a quantizer to generate second quantized data.

Abstract: A spread spectrum communication apparatus for communication with a plurality of communication units includes a reception circuit, an automatic gain control circuit, a spread spectrum code detection circuit, and a synthesis circuit. The reception circuit receives signals of a frequency channel inclusive of a target communication unit. The automatic gain control circuit controls the signal intensity of the frequency channel received by the reception circuit to a constant level. The spread spectrum code detection circuit detects the signal intensity of the spread spectrum code of the target communication unit from an output signal of the automatic gain control circuit. The synthesis circuit combines the signal intensity which is based on a gain control signal of the automatic gain control means with a signal intensity as detected by the spread spectrum code detection circuit to find a reception intensity.

Abstract: The invention provides a voice signal transmission system which reduces the amount of increase in calculation while suppressing possible deterioration of the performance by an expansion in the distribution of a voice parameter representative of an envelope of a voisce pectrum when input voice having a plurality of frequency characteristics is treated simultaneously. Discrimination circuit 5 discriminates, based on a voice parameter extracted by spectrum parameter extraction circuit 2, another voice parameter obtained by quantization of the extracted voice parameter by first quantization circuit 3 and a further voice parameter obtained by quantization of the extracted audio parameter by second quantization circuit 4, which one of either third quantization circuit 6 designed corresponding to first quantization circuit 3 or fourth quantization circuit 7 designed corresponding to second quantization circuit 4 should be used.

Abstract: An encoder apparatus is disclosed for encoding a wideband digital information signal. The apparatus comprises an input signal (1) for receiving the wideband digital information signal, a signal splitting unit (2) for splitting the wideband digital information signal into M narrow band sub signals (SB.sub.1 to SB.sub.M). The narrow bands all have a specific constant bandwidth. Further, a scale factor determining unit (6) for determining a scale factor for subsequent signal blocks in each of the sub signals, and a quantization unit (13) for quantizing the samples in a signal block into quantized samples are present. A bit allocation information deriving unit (34,41,48) is present for deriving bit allocation information, the bit allocation information being representative of the number of bits with which samples in a signal block of a sub signal will be represented after quantization in the quantization unit (13).

Abstract: A speech coding transmission system is disclosed in which a coder of a differential coding system quantizes a difference between a predictive value from an adaptive predictor and an input speech signal by an adaptive quantizer in accordance with the level of the latter and to send out the resulting coded signal to transmission medium, and a decoder outputs a reproduced speech signal on the basis of a residual signal obtained by inversely quantizing a received coded signal with an inverse adaptive quantizer and a predictive value from an adaptive predictor. Both or either one of the coder and the decoder includes a comparator-attenuator which attenuates the amplitude of the input signal or reproduced speech signal to a value smaller than a predetermined threshold value and applies to the amplitude-attenuated speech signal to the adaptive predictor.

Abstract: A data compression system can operate in a number of different configurations, and wherein the bit rate produced by a given configuration can be controlled over some finite range by a control signal from a rate controller for smoothly transitioning between the configurations so that discontinuous jumps in bit rate and distortion are minimized is provided by determining thresholds on the feedback control signals, the thresholds being used to determine when to switch in or out of each configuration; the thresholds furthermore being determined from the intersection points of the rate distortion curves for the available configurations.

Abstract: A new signal quantization scheme is proposed which reduces fluctuation of the output signal by a signal quantizer (10) providing a quantized output signal and multiplying (18) said input signal X by a factor (1-w.sub.1)and finding a difference signal .DELTA..sub.in (11) between both the input signal and the previous input signal and multiplying (16) that by a weighting factor w.sub.2 from a control (13). The previous quantizer output signal Q.sub.prev is summed (17) with the weighted difference signal .DELTA..sub.in w.sub.2 and the sum is weighted by a weighting factor w.sub.1 at a multiplier (19) to yield w.sub.1 (Q.sub.prev +w.sub.2 .DELTA..sub.in). This signal is then summed at an adder (21) and applied to the quantizer (10) so that the quantizer is forced to match the fluctuation in the input signal as well as the signal itself.

Abstract: Quantizing section 1 input audio signal data with a quantizing step width. First predicting section 14 predicts a quantization step width to be supplied to the quantizing section on the basis of the input audio signal and a number of bits of quantized data. Second predicting section 15 predicts the quantization step width on the basis of the input audio signal and a number of bits of quantized data. Coding section 2 performs Huffman coding on the quantized data. Calculating section 3 calculates the number of bits per unit time of the coded sequence signal. Selecting section 16 selects either one of the first and second predicting sections 14 and 15 on the basis of the input audio signal and the number of bits of quantized data. The first predicting section 14 further predicts another wider quantizing step width by a predetermined step width when the number of bits calculated is exceeded a predetermined value B.

Abstract: The present invention provides a transcoder for transcoding of digitally encoded bit streams produced by predictive encoders. The transcoder of this invention is less complex than previously known transcoders in terms of both computational and storage requirements. This efficiency is achieved by combining decoding and re-encoding steps into one step. This one-step transcoding is accomplished by modifying the originally quantized vectors and then requantizing and noiseless encoding these vectors into a bit stream in accordance with a predetermined objective.

Abstract: A quantization pattern codebook is prepared by way of: merging each pair of pattern clusters into a merged pattern cluster until all combinable pairs of the pattern clusters are merged to derive a set of merged pattern clusters; calculating the rate of bit increment by subtracting the total number of quantization bits in the pair of the quantization patterns used in the merging process from the total number of quantization bits in the merged pattern cluster derived from the pair of the pattern clusters; and determining the merged pattern cluster having a minimum rate of bit increment as one of the cluster patterns to be stored in the pattern code book.

Abstract: Caller identification information. e.g., the calling party number, is provided on a selective basis by the network of a carrier that does not directly contact the called subscriber at all, such as an interexchange carrier, to the next carrier carrying the call. For example, an interexchange carder would supply the calling party number to the local exchange carder (LEC) connected to a called party for an inter-LATA (long distance) call only if the called party subscribed to the interexchange carrier's inter-LATA caller identification (ID) service. Otherwise, the interexchange carder suppresses the calling party number, so that it is not supplied to the LEC. When the calling party number is supplied by the interexchange carder, the LEC would merely need to forward the number to the called station set. Such a system allows the interexchange carrier to control the providing of services that it heretofore could only assist in providing.

Abstract: In an image encoding apparatus, conversion data obtained by converting image information onto a frequency region, and corresponding to several frames are parallelly output using a one-frame-period delay circuit. The parallelly output conversion data are quantized by a quantization circuit, and a data amount to be obtained when the quantized data are encoded is obtained by a variable-length coding circuit. The data amount information is input to a coefficient operation circuit for determining a quantization step of the next stage. Conversion data quantized according to an output from the coefficient operation circuit are encoded, and the encoded data are output.

Abstract: A new signal quantization scheme is proposed which reduces fluctuation of the output signal by a signal quantizer (10) providing a quantized output signal and multiplying(18) said input signal X by a factor (1-w.sub.1)and finding a difference signal .DELTA..sub.n (11) between both the input signal and the previous input signal and multiplying (16) that by a weighting factor w.sub.2 from a control (13). The previous quantizer output signal Q.sub.prev is summed (17) with the weighted difference signal .DELTA..sub.in w.sub.2 and the sum is weighted by a weighting factor w.sub.1 at a multiplier (19) to yield w.sub.1 (Q.sub.prev +w.sub.2 .DELTA..sub.in). This signal is then summed at an adder (21) and applied to the quantizer (10) so that the quantizer is forced to match the fluctuation in the input signal as well as the signal itself. When applied to speech encoding algorithms such as the North American digital cellular telephone standard VSELP, the new quantizer results in more natural sounding background noise.

Abstract: A private branch exchange includes a detector that detects a transmission request to an external line by an extension terminal. An identifying circuit identifies the direct inward dialing number of the transmitting extension terminal and a transmitter transmits the direct inward dialing number of the transmitting extension terminal that is identified by the identifying circuit to the external line.

Abstract: A sigma-delta A/D converter having a digital logic gate core. The converter is comprised of a loop filter for shaping the converter's quantization noise spectrum. The loop filter is comprised of an unbuffered CMOS logic gate inverter which can be implemented by a gate array. A quantizer is coupled to the loop filter. A logic gate buffer is configured as a one-bit comparator, which is used to perform the quantization. This logic gate buffer can be one of the gates of a gate array. A sampler is coupled to the quantizer for sampling the quantized signal. This sampler can also be implemented by digital circuitry of a gate array. The signal from the sampler is fed into a decimator. The decimator outputs a digital signal representative of the amplitude of the analog signal.

Abstract: In connection with compression-coding of video signals on the basis of inter-frame correlation, a single reference table is used for variable length encoding of inter-frame motion vectors established on the basis of various motion vector value ranges and degrees of accuracy. A reference table is provided for variable length encoding motion vectors based on a particular value range and degree of accuracy. In order to use the same table for motion vectors based on a larger value range than that for which the table was designed, the value of a motion vector to be encoded is divided to form a quotient and a remainder. An addition bit code is formed on the basis of the remainder and is appended to a variable length code which corresponds in the reference table to the quotient so that a variable length code value is formed for the motion vector based on the larger range.