SU1295427A1 - Device for processing object images - Google Patents

Abstract

This invention relates to technical cybernetics and can be used in digital image processing systems. The purpose of the invention is to expand the functionality of the device by implementing the threshold median image filtering. The device contains a television sensor 1, an analog-digital converter 2, a group of shift registers 3, a generator of 4 pulses, a group of 5 elements I6, the first register 7, a control unit 8, a code sorting unit 9, a second register 10, a switch 11, a subtraction unit 12, the threshold setting register 14, the comparator 13 and the additional switch 15. In this device, the local median value is determined by sorting the pixel codes in the code sorting unit. Then the modulus of the difference between lo. the average median value and the current pixel is compared with a constant threshold by means of a comparator. Depending on the result of the comparison, either the median value or the current image of the reflection is received at the output of the second switch. 1 il. (Oh Vylod

Description

11295427

The invention relates to technical cybernetics, can be used in digital processing systems.

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The images, in part, for median image filtering, are an enhancement of the device according to ed. 1226500.

The purpose of the invention is the expansion of the field of application due to the provision of none of the threshold median filtering.

The drawing shows the block diagram of the device.

The device contained a TV sensor 1, for example a camera, an analog-to-digital converter (ADC) 2, a group of 3 shift registers, a generator, 4 pulses, a group of 5 Ibd elements

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the first register 75 control unit 8 control unit 9 sorting codes 5 second register 10, switch 11 ,. block 12 subtraction S comparator 13e register 14 setting the threshold and additional switch 15, as well as the first 16, second 17 and third 18 inputs of the device. A device for processing images of objects based on threshold median filtering implements the following function

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de f (isj) m (i, j) g (ij) m (i J) Jm (isj) -g (i, j) / 58j g (is j) s / m (i, j) -g (i , j)

image at the device output median of the area from the neighborhood of the current image element current image element at the device input

the threshold on which the device’s sensitivity to interference depends; i. an image element is diagnosed as an interference if it differs by more than a predetermined threshold from the median in the neighborhood.

An ordinary median filtering is obtained.

The device works as follows.

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Before the beginning of the median filtering of the input image, the mask code is recorded through the input 16 of the device 3 register 7. This code determines the formNo / area (from the neighborhood of the current image element), the elements of which calculate the local median value of the sequence of image elements located in If the image element is in the vicinity of the current image element corresponding to it

code bit recorded in register 7, It II

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equal to 1 5 otherwise this bit of the mask code O.

The CoI of the device input 17 in the register 10 is written the binary code of the number of that information input of the switch 11 ,; where the median code comes in: whose sequence of elements has been drawn. This number of the information input of the switch is 11 L, depending on the contents of the register .7

and is equal to () / 25 where N is the number of register bits 7, in which 1 is written,

Through the input 18 of the device in re-, „gistr. 14 threshold settings is written binary Threshold code S "For the 14 threshold definition register, a ring shift register with a parapel input (for setting the threshold via the setup input) and a serial output is used, since the parallel input code must be converted into a serial output - for comparison with the comparator a serial code received from subtraction unit 12,

The processed image during the line scanning of camera 1 through. ADC 2 enters in digital form at the input of the first shift register of the group of registers 3. When pulses are received from the generator 4 at the inputs of the shift control of registers 3, the pixel codes in registers 3 are sequentially shifted to form 3x3 neighborhood of the current pixel.

The codes of the elements of the image to be processed with the output of the 3 shift registers are in parallel fed to the first inputs of the 6I group elements, the second inputs of which simultaneously receive the values of the corresponding

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bits of the register 7. By means of cells I6, the bitwise logical multiplication of the image elements and the corresponding bits of the register 7 is carried out in order to select the area of a given shape,

. From the outputs of elements And 6 of group 5, the codes of the elements arrive at the inputs of block 9. The latter performs parallel-conveyor sorting of the input sequence n of binary image elements.

Calculating the median of a sequence of numbers is equivalent to sorting this sequence and choosing the sorted sequence of numbers as the center median.

The calculation of the median of the elements of the image is carried out by means of block 9. In the latter, the pair of parallel numbers is interchanged. As a result of pairwise parallel rearrangement of binary numbers, the codes of the sorted sequence of image elements are formed at the output of block 9. Thus, block 9 implements the parallel exchange sorting algorithm and operates in parallel-pipeline mode. From the output of block 9, the codes of the sorted sequence of picture elements go to the corresponding information inputs of the switch 11, to the control input of which from the output of the register 10 enters the binary code of the specified number.

The switch 11 and the register 10 are used to extract the current median image element from the sorted sequence of image elements at the output of block 9,

Due to the fact that the number of non-zero bits of register 7 is generally not equal to N, the median element is not the central element of the sorted sequence of binary numbers at the output of block 9, t, e. does not have a number (n + 1) / 2. Since the pixels are positive binary numbers, the median element has the number (N + 1) / 2 in the sorted sequence of numbers at the beginning of the numbering from the maximum element of the sequence to be sorted.

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Block 8 is used in the proposed device to control the process of sorting the sequence of image elements in block 9 of sorting codes

The signals 1 at the outputs of the control unit 8 determine the ends of the successive pixel codes that are supplied to the control inputs in the code sorting unit 9. The signal 1 from the first output of the control unit 8 is also fed to the control input of the comparator 13 to set it to the zero state.

At the output of subtraction unit 12, the binary code of the modulus of the difference between the local median value of the region from the neighborhood of the current element of the image and the current value of the central element 3 of this region is obtained. This binary code of the module is sequentially fed to one input of the comparator 13, and the second input of the comparator 13 also sequentially receives the binary code of the threshold 5 from the output of the register 14, the control of the register 14 for setting the threshold during filtering is carried out by means of clock pulses from the generator 4, Comparator 13 controls the operation of the switch 15 and feeds from its output to its control input the corresponding pulses of the control code. If the binary code of the difference modulus is greater than or equal to the binary code of the threshold value, the median of the region from the neighborhood of the current pixel is obtained at the device output through the switch 15, and if the binary code of the difference module is less than the binary code of the threshold value, the current value is set at the device output through the comparator 15 central element of this area.

Thus, introducing into the proposed device a subtractor of the threshold setting register, the comparator and the second switch allows expanding the functionality of the device by implementing the threshold median image filtering.

5th inference ratio

A device for processing images of objects by auth. No. 1226500, characterized in that.

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5,195,427 ft

in order to expand the field of application-subtraction, the output of which is connected

yi by providing thresholds for the first input of the comparator, the second

median filtering, it contains the input connected to the output

subtraction unit, threshold register register comparator, one of the threshold entered and the additional 5 D of which is the third input

a mutator whose output is a device and another input is connected

the output of the device, the output is corresponding to the output of the pulse generator, the shift register connected to the comparator's input is connected

to the first inputs of the subtraction unit and to-with the first output of the control unit, and

switch, the output of the com- 0; the output of the comparator is connected to the control switch of the switch connected to the second input of the additional commutator switch of the additional switch and blocker.

Claims (1)

SUMMARY OF THE INVENTION A device for processing images of objects by auth. No. 1226500, characterized in that. 1295427 '6 in order to expand the scope by providing threshold median filtering, it contains a subtraction unit, a comparator, a threshold register and an additional switch, the output of which is the output of the device, the output of the corresponding shift register is connected to the first inputs of the subtraction unit and additional switch , the output of the switch is connected to the second input of the additional switch and the subtraction unit, the output of which is connected to the first input of the comparator, the second input of which is connected to the output of the register To set the threshold, one of the inputs of which is the third input of the device and the other input is connected to the output of the pulse generator, the control input of the comparator is connected to the first output of the control unit, and 10 the output of the comparator is connected to the control input of the additional switch.