In an inter-frame predictive encoding system, reference frames are set. The reference frames are separated at equal intervals. The reference frames are selected from successively inputted frames of a video signal. Each of the reference frames is encoded. A prediction signal for a dependent frame between the reference frames is generated on the basis of a signal of the reference frames which precedes and follows the dependent frame respectively. A signal of the dependent frame is generated on the...

A video signal is coded for transmission in a restricted bandwidth by sub-dividing a frame of picture information into a set of constituent blocks, measuring the amount of picture activity in each block, sampling the information in each block at a rate related to the amount of picture activity in that block, and adding to the coded block a supplementary signal indicating the sampling rate used for the block. Thus a decision is made on a block-by-block basis as to whether the block is transmitted...

At the transmitter a coder includes a motion vector generator providing vectors (MV) describing the movement of individual blocks of pixels. The video signal is 4:1 compressed in bandwidth by pre-filters and a sub-sampling unit to produce a signal (SSH) from which a high-definition image can be re-constructed in the coder and in the decoder. The sampling lattice is shifted in accordance with the motion vectors (MV) which are digitally transmitted along with the compressed bandwidth analogue sign...

An image sequence transmission method and apparatus transmit a sequence of successive images over a bandwidth limited channel. The transmitter has a motion estimator for estimating the motion displacement between successive image frames of the sequence. The motion estimator divides each image into nonoverlapping blocks, each block including a plurality of picture elements. The apparatus then successively selects, in accordance with a steepest descent estimation technique, an initial value of a m...

A television signal which has a motion vector code signal and a prediction error code signal, is separated by a demultiplexer into a prediction error code signal and a motion vector code signal. These signals are decoded. A variable delay circuit receives an immediately preceding television signal from a frame memory and produces a prediction signal in response to the decoded motion vector signal. An adder receives the decoded prediction error signal and the prediction signal and produces a deco...

A predictive coding/decoding system for block-formed picture signals includes predictive coding and decoding units in transmitter and receiver sides, respectively: each of the predictive coding and decoding units is provided with a control pulse generator responsive to a horizontal synchronization pulse in the picture signal to produce a sampling signal and a select signal, and a pair of selectors together responsive to the select signal to select a sum of a prediction signal and a prediction er...

In order to encode image signals using interframe correlation while maintaining high data compression as well as high resulting images, a motion compensated interframe prediction error is orthogonally transformed and then is subject to quantization. Thereafter, the quantized error signal undergoes inverse orthogonal transformation. In order to compensate for distortions caused by the quantization, a difference between the inversely orthogonally transformationed error signal and the original pred...

In a movement compensation predictive encoder, a vector detector (19) is supplied with a moving picture signal and produces a movement vector signal representative of at least one movement vector for each region of each frame. A picture analyzer (16) serves as a variation detector for detecting a variation in each region to produce a variation signal when the variation exceeds a predetermined threshold in one of the regions. The variation signal is used in giving a predetermined value, such as z...

An inter-frame coding circuit for encoding a television video signal to reduce the quantity of data to be transmitted. The coding circuit includes a motion detection circuit which produces a motion vector representative of motion contained in the television signal and an inter-frame prediction coder which is responsive to the motion vector and to the input television signal to produce a prediction error signal which indicates frame-to-frame variations in the television signal. Also included is a...

In coding a digital video signal representative of successive pictures by using correlation between the successive pictures, each picture is divided into a predetermined number of blocks of picture elements. An original motion vector is used to represent a movement of each block between two pictures. The digital video signal is predictively coded by using the original motion vector to produce a coded signal. An on-off control signal is produced in order to determine whether or not subsampling is...