MULTIDIMENSIONAL DPCM CODER WITH A HIGH-PROCESSING SPEED

摘要

1. Multidimensional DPCM coder, the input (1) of which is supplied with digitized samples (si ) from which, by forming the difference within each case one estimated value (si ), DPCM signal values (DELTA si ) are calculated which are supplied to a quantizing device (QE) at the output (3) of which quantized DPCM values (DELTA si,q ) are output, characterized by : a) a series circuit of four subtracting units (SU1, SU2, SU3, SU4) which is inserted between the input (1) of the coder and the input (2) of the quantizing device (QE), b) a first computing loop, which is connected from the output (3) of the quantizing device (QE) via a first multiplier (M1), which multiplies the input signal by a constant prediction factor (a), back to the subtraction input (-) of a fourth one of the subtracting units (SU4) preceding the quantizing devices, c) a second computing loop, which is connected from the output (3) of the quantizing device (QE) via the first multiplier (M1) and via a second multiplier (M2), which also multiplies by the prediction factor (a), back to the subtraction input (-) of the third subtracting unit (SU3) preceding the fourth subtracting unit (SU4), d) a third computing loop, which is connected from the output of the quantizing device (QE) via a first adder (AD1), a second register (R2) and via at least one multiplier (M3, M4), multiplying by the third power of the prediction factor (a), back to the subtraction input (-) of a second subtracting unit (SU2) preceding the third subtracting unit (SU3), in which arrangement the third computing loop e) contains an inner computing loop which exhibits the first adder (AD1) connected to the output (3) of the quantizing device, the output of which is connected via a series circuit of the second register (R2) and a third multiplier (M3) multiplying by the prediction factor (a) and via a second adder (AD2) back to the second input of the first adder (AD1), f) a fourth computing loop which is connected via the first adder (AD1) and a line predictor (PRL) which outputs an additional estimated value (szi+1 , szi+2 ) at an output (8, 9), back to the subtraction input of a first subtracting unit (SU1) which precedes the second subtracting unit (SU2) and in which a further output (6) of the line predictor (PRL) is connected to the second input of the second adder (AD2).