RU2277262C1 - Photogrammetric workplace - Google Patents

Abstract

FIELD: computer science, namely, engineering of devices for producing images, specifically meant for photogrammetry.

SUBSTANCE: photogrammetric workplace contains standard personal computer in base configuration, consisting of system block, monitor, keyboard, mouse-type graphical information manipulator and printer, and stereoscopic video control device, consisting of color monitor, coordinate joystick, parallax joystick, light-valve goggles and monitor adapter, first inputs-outputs of which are connected to system block of personal computer, first output - to input of color monitor, and second output - to input of light-valve goggles.

EFFECT: expanded functional capabilities, decreased dimensions, increased reliability of photogrammetric workplace.

3 dwg, 1 tbl

Description

Technical field

This technical solution relates to the field of computer technology, namely, devices for obtaining images specially designed for photogrammetry.

State of the art

An analogue of this technical solution is the well-known device - Computing complex "Analit" RDPI 320.308 with appropriate software.

A disadvantage of the known analogue is the lack of visualization of graphics and, accordingly, accurate control and correction of the digital elevation model (DEM).

Another analogue of the claimed technical solution is a photogrammetric device - Inter Map 6487 Image Station (INTERGRAPH. USA) (see advertising materials INTERGRAPH Solutions for the Technical Desktop), containing a digital stereo plotter, stereo review system, a processor for compressing / decompressing data to minimize image file memory ergonomically designed table.

The disadvantages of this analogue:

- no guidance is provided to the image point with an accuracy of _^1/4 pixel;

- it is not possible to smoothly move graphics across the image for monitoring and subsequent correction of products by the operator;

- the high cost of equipment.

The closest analogue (prototype) of the claimed device is a PHOTOGRAMMIC WORKPLACE (patent for invention RU 2225593 C2, application No. 2002109417 from 10.0.2002, published March 10, 2004, bull. No. 7/2004), containing a personal electronic a computer (PC) in the basic configuration, consisting of a system unit with a monitor, keyboard, graphic mouse manipulator and printer connected to it, a stereoscopic video monitoring device (CMS), consisting of a color monitor, polarized screen th filter (PPF), joystick coordinates (ANC) and a joystick parallaxes (JP) and the remote operator and the controller stereoscopic video control device.

The disadvantages of the prototype are the execution of the controller IMS on microcircuits with a small degree of integration and, as a result, large sizes and low reliability.

The essence of the technical solution

The well-known photogrammetric workstation contains a personal electronic computer (PC) in the basic configuration, consisting of a system unit with a monitor, keyboard, graphic mouse manipulator and printer connected to it, a stereoscopic video monitoring device (IED) consisting of a color monitor, joystick coordinates (ДЖК), parallax joystick (ДЖП) and light valve points (СО).

The purpose of this technical solution is to create a photogrammetric workstation for processing space and aerial photographs to obtain digital elevation models and cadastral plans with wider functionality with a simpler structure through the use of LSI and FPGAs and lower cost characteristics.

To achieve this goal, the photogrammetric workstation additionally contains an SVKU monitor adapter, the first inputs and outputs of which are connected to the PC system unit, the first output with the input of the SVKU color monitor, and the second output with the input of light-valve glasses.

The ICS monitor adapter contains a left-side memory (RAM) of the left frame (LCP RAM) and a right-frame RAM (PKP RAM) for fixing the image density of the left and right frames, left-frame RAM (RAM LKG) and right-frame RAM (PCG RAM) for fixing graphics, RAM control device - SDRAM control, adapter control unit (CU) connected to the SDRAM control device via control, address and data buses and the first output with a PC expansion bus, digital-to-analog converter (DAC), the input of which is connected to the second output device control devices (CU), operational amplifiers, the inputs of which are connected to the outputs of the digital-to-analog converter (DAC), and the outputs with the R, G, B inputs of the color IED monitor, the driver of light-valve glasses, the input of which is connected to the third output of the control device (CU) , and the output with the entrance of the light-valve glasses.

The joystick contains variable resistors Rx and Ry, a control knob mechanically connected to the axes of the variable resistors Rx and Ry, an analog-to-digital converter (ADC), the two inputs of which are electrically connected to the outputs of the variable resistors Rx and Ry, and the other two with the outputs of the variable resistors of the other joystick, VVC forming unit, the output of which is connected to the third input of the analog-to-digital converter, and two inputs with PCS serial communication (COM) port RTS and DTR connectors, personal computer communication unit with serial port (COM), two inputs which X and Y are connected to the outputs of the analog-to-digital converter (ADC), the third R × D and the fourth T × D inputs and output ± X, Y, respectively, with the outputs R × D and T × D and the input ± X, Y of the communication connector serial port (COM) of the PC.

List of drawings

Figure 1 shows the structural diagram of the photogrammetric workplace.

Figure 2 shows a structural diagram of a monitor adapter for a stereoscopic video monitoring device.

Figure 3 shows the structural diagram of the joystick.

An example embodiment of the device.

A variant of the principle of stereoscopic measurement implemented in the device is a fixed mark, a moving model. Moving the left image of the model relative to the right leads to a visible movement of the model along the line of sight (to or from the operator). The left and right images of the brand are motionless and combined. Parallax brand (RMK) is zero. The mark constantly lies in the plane of the screen. The operator, changing the parallax of the model (Rmd), moves it and combines the image of a point on the surface of the model with the image of a fixed mark. In this case, the parallax point of the model, combined with the brand, is Rmd-Rmk. The reading accuracy is 1 pixel - the minimum value by which the left and right images of the model can be moved apart (shifted).

A feature implemented in the sample is the ability to display the left and right brand images not only at one point, but also at distances of 1/4, 2/4 and 3/4 pixels between them. This change in the parallax of the mark moves it along the axis of view and makes it possible to measure the parallax of the model points relative to the mark with an accuracy of 1/4 pixel. In this case, as usual, the model can move through 1 pixel. The monotonic movement of the model relative to the brand is as follows (the initial parallax of the model relative to the brand P, see table):

Table Parallax model Parallax brand Parallax models relative to the brand R 0 P + 0 R - ^{a _1/4} P + ^_1/4 R - ^_2/4 P + ^_2/4 R - ^_3/4 P + ^_3/4 P + 1 0 P + 1 P + 1 - ^{a _1/4} P + a 1 ^_1/4 P + 1 - ^{a _1/4} P + 1 ^_2/4 P + 1 - ^{a _1/4} P + 1 ^_3/4 P + 2 0 P + 2 P + 2 - ^{a _1/4} P + 2 ^_1/4

The parallax of the model changes through the pixel, the parallax of the brand through 1/4 of the pixel. The measured parallax equal to the difference between the parallax of the model and the brand changes through 1/4 of the pixel.

In principle, one bit per pixel is sufficient to display graphics. Zero - no graphics. Unit - The pixel is filled with the color of the graphic. However, in this case, the resolution of the display of stereoscopic graphics in parallax (height) will correspond to one pixel. Operators claim that they see the displayed profile in steps, while the terrain looks smooth. A parallax step equal to a pixel is large.

A feature of the device is the allocation of a byte of memory for each pixel of the graphics raster. Bytes corresponding to empty pixels (no graphics) are empty. In bytes corresponding to pixels containing graphic points, the following are written: in two digits - the offset of the graphic point relative to the nominal position, expressed in quarters of a pixel, in the remaining digits - the number of trajectories (graphic image - profile, horizontal, etc.). This structure allows you to store in the graphics memory not one display object, but several (up to 64). This allows at each moment of time to highlight only those graphic objects whose numbers are given (up to three). In addition, without any preparation, you can show some sequence of images (animation), sorting through their numbers. So it is possible to show the profile of the relief, smoothly sliding along it, or contour lines, smoothly moving in height. These effects significantly accelerate the control of the calculated relief while improving the quality of control.

The presence of an offset recording allows you to implement it by delaying the displayed point in time by a recorded amount, which raises the quality of the graphic display. For the operator, this virtually eliminates the stepping of the displayed profile.

Photogrammetric workstation (FRM) (figure 1) contains a personal electronic computer (PC) 1, consisting of a system unit 2, a monitor 3, a keyboard 4, a mouse-like graphic information manipulator 5, a printer 6 and a stereoscopic video monitoring device (IED) ) 7, consisting of a color ICS monitor 8, a monitor adapter 9, a coordinate joystick (DLC) 10, a parallax joystick (DJP) 11, and light-valve glasses (СО) 12.

The ICS monitor adapter (Fig. 2) contains left-side memory 13 (RAM LCP), right-side RAM 14 (control panel RAM) with a minimum required capacity of 16 MB for fixing images of left and right frames, left-side RAM 15 ( RAM LKG), RAM of the right frame 16 (RAM PCG) with a minimum required capacity of 16 MB for fixing graphics with the control device SDRAM 17, which controls the writing-reading of RAM from (in) the PC through the control device (CU) 18, which connects to the PC via the system bus 22.

The digital-to-analog converter 20, which converts digital information from RAM, generates and transmits to the monitor 8, via operational amplifiers 19, the brand, graphics and image, as well as control signals, in the analog form and color, as well as control signals, at the same time as the driver sweeps the left frame (control circuit ) light valve points 21 opens the left point to the operator, and when sweeping the right - the right point. To control the movement of the image on the monitor screen in plan and in height, the control system has a joystick of coordinates 10 and a parallax joystick 11, which are connected to the PC serial port through connector 28.

The joystick diagram (Fig. 3) consists of variable resistors 23 and 24, the deviation of the handle 29 of which the operator controls the movement in the image: the deviation angle indicates the direction and speed of movement along the coordinate (s). The analog signals from resistors Rx 23 and Ry 24 are fed to an analog-to-digital converter 26, which provides digital signals to a communication unit with a PC serial port, which in turn controls the reception of information through R × D and T × D signals. Since there is no power output in the COM port, it is formed in the joystick circuit from the RTS and DTR logic level signals supplied to the input of the VCC 25 forming unit, where a stabilized 5 V voltage is supplied to all elements of the joystick. Blocks 26 and 27 are physically combined in one chip - the ATMEGA8-16PI microcontroller.

Appointment

A stereoscopic video monitoring device (CMS) is designed to visualize a stereo model on a monitor screen and perform measurements of its parameters in an interactive mode.

CMS is used as part of a photogrammetric workstation when receiving information about the terrain in the form of a digital terrain matrix for its further use in the process of digital cartography.

Specifications

ICS has the following main technical characteristics:

the amount of RAM image, MB, not less - 32 amount of graphics RAM, MB, not less - 32 RAM frame format, pixels - 1024 × 1024 pixel width, bits - 8 way to connect the operator with the image - two joysticks stereo image switching method - through light valve glasses monitor type - color, 19 ", 0.25 LR monitor frame format, dots - 800 × 600 frame rate, Hz, not less - 120 type of system bus PC for installation adapter - ISA MTBF, h, at least - 5000

powered by AC from 187 V to 242 V at a frequency of (50 ± 1) Hz

Composition of CMS

The following products are included in the ICS:

- joysticks (2 pcs.);

- monitor adapter (installed in the PC system unit);

- color monitor, 19 "; 120 Hz;

- light-valve glasses.

The device and operation of the control system

Structural diagram of CMS

It is based on random access memory (RAM), with a format of 1024 × 1024 × 8 bits (one frame). There are two types of RAM: RAM for fixing the image and RAM for fixing various kinds of graphic lines superimposed on the image. Each RAM, in turn, consists of two parts - RAM of the left frame for fixing the image density and graphics (RAM LCP, RAM LKG) and RAM of the right frame for fixing the density of the image and graphics (RAM PKP and RAM PCG). The total RAM capacity is 64 MB (8 frames). RAM is implemented on a standard PC RAM module.

The RAM through the control device (UE) is connected to a digital-to-analog converter (DAC), a graphic dot former (FTG) and a brand dot former (FTM). The signals from the outputs of these nodes through analog amplifiers are fed to the monitor input.

At the same time that signals are sent to the monitor from the control unit through the light valve glasses driver (DRCO), glasses control signals are issued: synchronously with the output of the left frame, observation with the left eye is allowed, and the right frame is observed with the right eye. The frames are displayed on the screen with a high frequency, while the operator sees one embossed image on the monitor screen.

How the monitor adapter works

On the monitor screen, the image is formed of three layers. The bottom layer is the surface topography. Data for this layer are obtained in the process of measuring the optical density of the photograph. Each image point is described by one byte and is encoded by a number ranging from 255 to 0. The brightness of the image points corresponds to the optical density of the image, the image color is brown. The middle layer is graphics. The data byte that describes the graphics points contains two attributes - a conditional number and a shift. The graphic point is displayed on request. At the same time, points with three conditional numbers can be displayed. In the graphics animation mode, points with numbers corresponding to the animation counter value are sequentially displayed on the screen. The animation counter is controlled by a clock received from a frequency synthesizer. The animation speed depends on the frequency of the clock signal and is set by the operator. The shift code controls the position of the graphic point relative to the corresponding image point.

Graphics points can be displayed with a shift of 0, 0.25, 0.5, or 0.75 pixels relative to the corresponding image points. Graphics are displayed in dots of green or red in size of 0.5 pixels.

The top layer is the sight and mark. Data for this layer is stored in read-only memory (ROM) built into the programmable logic integrated circuit (FPGA) of the control device. This layer is blue, the size of the mark and the shape of the sight are selected by the operator. The reticle is designed to facilitate the search for the brand. The mark can have a size of 0.5, 1.2 or 3 pixels.

Two modes of brand output are provided - constant glow and flicker. The flicker frequency of the brand is selected by the operator. When layers of color mixing are not applied, the top layer always covers the bottom. The mark can move relative to the image in increments of 0.25 pixels.

Joysticks

The operator controls the movement of the image on the screen through two joysticks, the handle deviation signals of which are fed to the COM1 port of the PC via the RS-232 interface. The coordinate joystick (DLC) is connected to the COM1 port, and the parallax joystick (DLC) is also connected to the COM1 port, but through the second ADC input to the DLC (reverse connection is possible). The deviation of the handle indicates the direction of movement, and the angle of deviation determines the speed of movement. In some technological processes, the function keys of the PC keyboard are used to move the image.

Monitor

The UCSU uses a 19 "serial color monitor.

Industrial applicability

A photogrammetric workstation is industrially feasible, has wider functionality, a simpler configuration and better cost characteristics.

Claims (1)

A photogrammetric workstation (PCF) containing a personal electronic computer (PC) in the basic configuration, consisting of a system unit with a monitor, keyboard, graphic mouse manipulator and printer connected to it, a stereoscopic video monitoring device (CMS), consisting of color monitor, coordinate joystick (JJC), parallax joystick (JJP) and light valve points (СО), characterized in that it additionally contains an SVKU monitor adapter, whose first inputs and outputs are connected They are not connected to the PC system unit, the first output is with the input of the color monitor of the VCRS, and the second output is with the input of the light-valve glasses, the adapter of the monitor of the VCRS contains random access memory (RAM) of the left frame (RAM LCP) and RAM of the right frame (RAM of the control panel) for fixing image density of the left and right frame, RAM of the left frame (RAM LKG) and RAM of the right frame (RAM PCG) for fixing graphics, control device RAM control SDRAM, control device adapter (CU) connected to the control device SDRAM via control buses, addresses and data and lane an output with a PC expansion bus, a digital-to-analog converter (DAC), the input of which is connected to the second output of a control device (CU), operational amplifiers, the inputs of which are connected to the outputs of the digital-to-analog converter (DAC), and the outputs - to the inputs of the monitor color IED, driver of light valve glasses, the input of which is connected to the third output of the control device (CU), and the output is connected to the input of light valve glasses, the joystick contains variable resistors Rx and Ry, a control handle mechanically connected to the axes of the variable resistor ditch Rx and Ry, an analog-to-digital converter (ADC), the two inputs of which are electrically connected to the outputs of the variable resistors Rx and Ry, and the other two to the outputs of the variable resistors of another joystick, the VVC forming unit, the output of which is connected to the third input of the analog-digital a converter, and two inputs - with the RTS and DTR outputs of the PC serial communication port (COM), the communication unit - with the PC serial port (COM), the two inputs of which X and Y are connected to the outputs of the analog-to-digital converter (ADC), the third R × D and fourth T × D input s and output ± X, Y, respectively - with the outputs R × D and T × D and the input ± X, Y of the connector for communication with the serial port (COM) of the PC.

Images