SU1644185A1 - Graphic data reader - Google Patents

Description

one

(21) 4647991/24 (22) 07.02.89 (46) 04.23.91. Bul Number 15

(71) Kaunas Polytechnic Institute A.Snechkus

(72) A.S.Shalash vicus, A.Yu.Ambrazas, A.Yu.Lepuonis and I.K.Punis (53) 681.327.12 (088.8)

(56) USSR Copyright Certificate No. 985801, cl. G 06 K 11/00, 1981.

USSR author's certificate Ne 1462374, cl. G 06 K 11/00, 1987.

(54) DEVICE FOR READING GRAPHIC INFORMATION (57) The invention relates to automation and can be used to read graphic information. The purpose of the invention is to simplify the device and increase its speed. The delivered chain is achieved by forming a continuous recursive Hilbert scan that is provided by connecting the counter to the output of the AND element, and the outputs of the elements NOT to the corresponding inputs of the EXCLUSIVE OR elements of the second and third groups. 8 il.

The invention relates to automation and computing technology and can be used in information and computing systems, in computer aided design, control, training, and also in computer aided image processing systems as means of reading graphic information for inputting it into a computer, transmitting it to display devices or into the storage system.

The purpose of the invention is to simplify the device.

Figure 1 presents the block diagram of the device; figure 2 and 3 are examples of the implementation of signal conditioners; 4–7 shows the standard Ј1e of the Hilbert cell (initial, after coordinate exchange, after inversion, and after coordinate exchange and inversion); on Fig - hodograph of the electron beam

indicator for the raster dimensions of 8x8 elements.

The device (figure 1) contains the generator 1 pulses, the element And 2, the counter 3, the group of elements And 4, the elements NOT 5, the first group 6 elements EXCLUSIVE OR, the second 7 and the third 8 groups of elements EXCLUSIVE OR, performed as pulse shapers (Fig .2 and 3), switching unit 9, represented by switches 10 and 11, indicator 12, containing shaper 13 signals, blocks 14 and 15 of the beam deflection, CRT 16, blocks 17 and 18 of the elements HE. In addition, the outputs 19 and 20 and the input 21 are shown.

Shapers 7 and 8 (Fig.2 and 3) can be made from the group of elements EXCLUSIVE OR 22.

The device works as follows

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The signal from input 21 arrives at AND 2 and sets the counter 3 to the initial state.

The output bits of counter 3 are divided into pairs, each of which is connected to the inputs of the corresponding elements EXCLUSIVE OR of the first group 6, since all inputs of these elements receive zeros, there are also zeros at their outputs, i.e. there is a zero code (Y coordinate code). The even bits of counter 3 form the X coordinate code. Each bit of the switches 10 and 11 forms a pair of switches, which, in the presence of a control single signal, changes the corresponding bits of the X and Y coordinate codes between themselves. Since zero codes arrive at the inputs of both switches 10 and 11, regardless of the switching of their bits, there are also zero codes at their output, which arrive at the inputs of blocks 17 and 18. Each element of these blocks is an EXCLUSIVE OR element and is intended for inverting bit code arriving at its first input, in the presence of a control single signal from the driver 7 signals at the second input.

In this case, the driver 7 generates single control signals, since the second input of the driver 7 of the signals from the HE elements 5 receives a single signal, which, despite the fact that the And 4 elements receive the zero code, generates the single code .

Thus, both in the first 17, and in the second 18 block of elements, NOT all bits, except the older ones, are inverted, and two type codes 01111 ... arrive at the beam deflection blocks 14 and 15, determining the corresponding deflecting current of the beam of the indicator 12 Immediately after the turn-on signal, input signal 21 is received from the imaging unit, 1 opening modulator of the CRT 16, and the beam is illuminated. It is not required to extinguish it, since it does not move anywhere, but immediately illuminates one of the four central points of the screen, i.e. point 00 (Fig. 8, the numbers on the hodograph show the numbers of the raster points read by the counter 3 and successively traced by the electron beam in accordance with the Hilbert sweep, and the numbers on the coordinate axes show the codes arriving at the beam deflection blocks 14 and 15),

In counter 3, the clock pulses are summed, the code from its outputs is divided into two k-bit codes, one code — the X coordinate code — is obtained by selecting the even digits of counter 3, and the other Y coordinate code — by performing the EXCLUSIVE OR operation on even and odd bits in a group of 6 elements. The bits of these two codes are modified on the switches 10 and 11, as well as on blocks 17 and 18, and arrive as control codes in blocks 14 and 15 of the beam deflection, causing the beam of the CRT 16 to move according to the Hilbert scan law. In addition, the obtained coordinate codes at the outputs 19 and 20 can be written into the external buffer memory of the user of graphic information, for example, at those times during the scanning process.

beam CRT 16 goes to the point of graphical information.

The Hilbert scanner hodograph (Fig. 8) is obtained from the reference scan cells, and these cells are respectively rotated and (or) mirrored.

The set of reference cells throughout the frame is formed by the initial codes of the X and Y coordinates from the even bits of the counter 3 and at the output of group 6 of the EXCLUSIVE OR elements. The rotations of these cells are performed on the switches 10 and 11 by exchanging bits between the coordinate codes (Fig. 5). Changing the bits of these codes is only necessary when the number of zeros

in the higher bits of the code, the Y coordinate is odd. The control signals to the switches 10 and 11 come from the driver 8 pulses. A single control signal of this block appears when an odd number of units enters its higher input bits. The determination of the oddness of units is performed by series-connected elements EXCLUSIVE OR, but, since a constant zero signal is on (k - 1Om output bit, the units are counted only up to (k - 2) -ro discharge. the code zeros of the Y coordinate, converted to units by elements NOT 5.

The mirror reflections of the reference cells are performed by blocks 17 and 18 by inverting the bits of the X and Y coordinate codes (Fig. 6).

The selection of such pairs is carried out by the elements HE 5 and the group of elements AND 4, and the determination of their oddness and the generation of control signals for the corresponding bits are made by the driver 7

pulses.

Shaper 7 and 8 do not use lower input and high output bits. Therefore, the groups of elements NOT 5 and elements 4 do not contain elements of processing the first bits, and the switches 10 and

11 and blocks 17 and 18 do not modify the higher bits of the coordinate codes.

At the end of the scan frame, filled with counter 3, i.e. its contents will be 111 ... 1, the beam of the CRT 16 is at point 63 (Fig. 8). When another clock pulse arrives, the counter 3 enters the state of 000 ... O, which corresponds to point 00 on the hodograph (Fig. 8). Since point 00 is adjacent for point 63. the indicator beam, the transition to scanning the next frame is not suppressed.

The device stops the scanning process after resetting the turn-on signal to the device input 21.

Claims (1)

Invention Formula A device for reading graphic information containing an AND element, one input of which is the synchronization input of the device, another one connected to the output of the pulse generator, a counter, the installation input of which is connected to the synchronization input of the device, and the outputs connected to the inputs of the corresponding elements EXCLUSIVE OR of the first group, indicator whose sync input is connected to the sync input of the device, information inputs are connected to the outputs of the switching unit, and the control input is connected to the output of the EXCLUSIVE OR elements of the second group, the elements are NOT whose input is connected to the output of the corresponding elements EXCLUSIVE OR of the first group, the elements AND groups, one input of which is connected to the first output of the elements NOT, the other is connected to the output of the last digit of the counter, and the output is connected to one input of the EXCLUSIVE OR elements of the second group, and the third group of elements EXCLUSIVE OR, whose output is connected to one information the switching unit, the other information input of which is connected to the output of the EXCLUSIVE OR elements of the first group, and the control input of the switching unit is connected to the output of the last digit of the counter, characterized in that, in order to simplify the device, the output of the AND element is connected to the counting input of the counter, the second input of the elements EXCLUSIVE OR of the second group is connected to the second output of the elements NOT, the first output of which is connected to the inputs of the corresponding elements EXCLUSIVE OR of the third group. 1