SU1396293A1 - Device for predicting image signal in differential encoding - Google Patents

Abstract

The invention relates to a television technique. The purpose of the invention is to increase the prediction accuracy. The device contains a pulse frequency divider (DRCI) 2, switch 6, delay unit 7, input 8 and image signal output 9, clock frequency input 10, row frequency pulse input 11, field frequency pulse input 12, sync pulse input 13 chronizadia. Two shaper 1 and b control signals and two LFR 3.4 are entered into the device. The inputs of the switch 6 receive signals B and C of the image from the outputs of block 7 delayed relative to the input signal A of the image, respectively, by Hj, and n samples. at the entrance. The main feature is that the prediction of every two adjacent samples of the input signal A is carried out, according to one value of the signal of the signal J). In the case of the chess structure of discretization, the prediction of the current counts of the television image is carried out in a diagonal direction, 5 Il. i SL

Description

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I The invention relates to a television technique and can be used to predict an image signal in television systems with differential coding.

The purpose of the invention is to improve the accuracy of the prediction.

FIG. 1 shows the electrical: a block diagram of an image signal prediction device in a differential encoding; in fig. 2 is a diagram of the first driver of the control signal in FIG. 3; and a diagram of the second driver of the control signal J in FIG. 4 is a fragment of a thermal raster with a staggered sampling structure and a prediction direction of current samples of the image t in FIG. 5 is a timing diagram for explaining the operation of an image signal prediction device in differential coding.

I The device for predicting the signal L13 for differential quoting (Fig. 1) contains the first driver 1 of the control signal, the first, second and third dividers 2, 3 and 4 pulse frequencies, the second driver 5 of the control signal, the switch 6, the delay unit 7, the input 8 image signals,. 9 image signal output, 10 active frequency pulses input, 11 pulses input Line frequencies, 12 clock pulses input, Field plots, 13 synchronization pulses input.

The image signal predictor in differential coding operates as follows.

First, the shaper 1 provides for obtaining a sampling sequence of pulses with phase switching 180 from line to line and from frame to frame (Fig. 5 a). Discretization of the image signal using such a sequence of pulses Leads to a checkerboard structure of the location of counts on the television raster (Fig. 4). The discretization signal from the output of the first shaper 1 is fed to the clock input of block 7 and after dividing by 2 in the second divider 3 (Fig. 5 b) to the input of the second shaper 5 of the control signal (Fig 5 b). To obtain the required control signal, which determines the switching mode of the switch 6, to the inputs of the second generator

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l 5, the frequency pulses of the rows (divided by four in the first divider 2) and the frequency pulses of the fields divided by two in the third divider 4 (FIG. 5 g) are divided by four in the first divider 4. To ensure the synchronization of the operation of the first imaging unit 1 and the first, second and third dividers 2, 3 and 4, synchronization pulses are received at their installation inputs, which set all the specified blocks once per television frame to its original position.

As a result of switching the phase of the signal (fig 5) at 180 ° every two lines and from field to field at the output of the second shaper 5 a signal is formed (Fig. 5 d), which is fed to the control input of switch 6. On the first and second signal the inputs of the switch 6 receive the signal B from the first image and the image signal C from the second output of block 7, delayed relative to the input signal A of the image respectively on p. 1 and p. (Figs. 5e, g, g, u). As a result of connecting one of the delayed signals B or C to the input of switch 6 in accordance with the control signal (Fig. 5e), a prediction signal D is generated at the output, which serves to estimate the current values of the image signal input to the input. The main feature is that the prediction of every two adjacent samples of the input signal A is carried out on one value of the signal of signal D. For example, the input values of the thirty-third and thirty-fourth samples (signal A) correspond to the output of the device (signal D) one value twenty-third reference (Fig. 5 e, g, s, and). With an optical sampling structure, such an algorithm causes the prediction of current samples of a television image to be performed in a diagonal direction, as shown by the arrows in FIG. 4. The twenty-third sample, predicting the thirty-third and thirty-fourth samples, is located on the previous line and is shifted relative to each of the predicted samples by half the sampling interval.

Claims (1)

Invention Formula An image signal prediction device in the differential 31 coding, containing a delay unit and a switch, the first and second signal inputs of which are connected respectively to the first and second outputs of the delay unit, as well as the first pulse frequency divider, whose signal and setup inputs are inputs respectively pulse frequency lines and pulses synchronization, characterized in that, in order to improve the accuracy of the prediction, the first form The world of the control signal, the first and second inputs of which are respectively the inputs of the clock frequency pulses and the field frequency pulses, and the third and quarter inputs are combined respectively with sigQ five 0 the input and installation inputs of the first pulse frequency divider, the second pulse frequency divider, the other input of which is combined with the installation input of the first pulse frequency divider, and the second control signal generator, the second input of which is connected to the output of the first pulse frequency divider, and the transducer c control to the switch input, as well as the third pulse frequency divider, the signal and the set inputs of which are connected respectively to the second input of the first control signal generator and to the installation input of the first pulse frequency divider, and the output is connected to the third input of the second driver of the control signal. cpus2 O-f L & fi.Z 12 54SS56 y v y // one 7G D / - /  23 / 5 / hJ2 M / H 4i y / / J -FJJ fig.h  one tg  one D / 23 y 25 L -l- /  / J54 Jff /  6 (pa.eS