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Transcription

1 automated mapping and resting upon data. use of aerial in compilation planning-carmanagement of informaone of m comes topographic boundaries, hydrography, road network, reup topo-basis of future forest map, and information about contours and forest mensuraforest plots from aerial or space pho flows done by control points interactive mode. The improvesecond examon ecodeter... control sta... is set by base. order both information

2 and in and... """... "',.,.,.- - development ration data - joint information; - information output mation). ers: ae topographic maps, geodetic data tapes; entered information including error contour information control points, and contour transformat; rectification of mutual adjustment area calculation; cartographic and forest mensu relational tables complex; aerial space and cartographic nhi~t4~~~a[)hs, by requests (including cartographic infor- In order to solve tasks systems should have owing technical characteristics. Input devices allow to read photographs lor, multispectral photo film, 300x300 and information aerial and space and scales, black-and-white, copositives, written on tape. The frame format is 6_,~_~~u _~ make up 25 and 50 microns. Information from outlines photo-outlines is read by television input device. Information from maps read with help of digitizer of format AO. Image discretization on color raster display makes 256 x 256 and 52 x 52 elements. For correction of graphical information a vector display is used. Map plotting is done with plotter of format AO in four colors at 800 mm/sec. All peripheral devices are united working places controled by mini-computers. storage magnetic disks with capacity 96 of s Compilation s forest managecartographic materials. To ma,n82emenc materials we refer fostands plans and plans of maps include non-tradiinformation about fomanagement bodies,... VI'IIIJ.a.... ed at laron forest forest maps. cartographic materiof corresponding

3 scales. However one must accuracy of drawing mind that requirements on are... _4_... All lines (showing boundaries of various area units and linear objects, and determining trajectories legend plotting) and points (fixing location of control points and symbols) may be divided into three classes according to requirements set towards accuracy of ir description and plotting. To first class we refer those elements which determine metric accuracy of document. These are control points, district boundaries of State forest fund lands and or administrative boundaries, hydrography, road network, compartment openings, etc. In use of vector format coordinates of se lines and points must be known with accuracy of fractions of mm at scale of output document. The totality of elements of first class accuracy up frame cartographic document. Boundaries of forest mensuration plots (especially those established by way of contour interpretation of aerial space photographs) and or "washed away" ground objects refer to second class contours which form filling of frame cells. Their coordinates must known with accuracy of units of mm at scale of < output document. The third class includes lines main requirement to accuracy of description of which is observance of ir correct location and orientation towards or area and linear objects. These are shading lines, lines determining legend positions, frame contours, etc. To this class also points determining location of same symbols and legends having predetermined orientation are referred. The frame elements are entered into computer eir by means of presenting information in digital form (for example data obtained in process of geodetic survey of district boundaries of State forest fund lands) or with help of precision input devices (for example schematic map digitizer) from highly accurate cartographic materials (road network, hydrography, control points, etc.). Information about objects of second class (for instance about forest mensuration plot boundaries) is entered into computer with help of television input devices in combination with raster display systems of a low resolution (52 x 52) from aerial space photographs, outlines or old corrected maps, and coordinated to axes of frame by means of different transformations (flat-para,ll transfer, linear stretching, projecting transformation) chosen in accordance with type of a document with source data by control points. Coordinates of third s aments are usually determined automatically or with programming means with minimal interference of operator. Thus through detailization of requirements to map accuracy is possible to get an access to information of different accuracy and to reduce time of information input while increasing automation degree of procedure of entering source data and reducing requirements to ir accuracy.

4 requires photographed terrain. relief data process of interpretation range tasks solved and improves results accuracy. For determination of forest mensuration indices of stands growing under mountain conditions additional features (slope, exposition, point height, etc.) which can be extracted from digital relief model (DRM) are required. Contour interpretation of photos with determination of relief elements (watersheds, valley lines) is done more accurately and in more detail. Land category extraction by photographs is also ed accuracy relief data is necessary that each space photograph be supplied with local DRM which is related to photograph in scale and coordinates, and photograph should be processed toger with DRM. In data base ASFIM division which isolinear relief models in vector format are stored been created. There is anor division in which data about control points is concentrated. In joint processing of a space photograph and DRM a number of control points which are stored in cartographic data base is marked. photograph called photograph plane by selected control points. raster display system superposed composite terrain images read from space photograph, and isolinesr DRM transformed into raster format are shown. Then by isolinear model hypsometric relief model defined on same raster as terrain image and combined with it is built. After mentioned preparatory operations memory raster display system we have local hypsometric DRM each pixel of which contains information about height of terrain point defined on image with pixel with same coordinates. Then joint processing of image and DRM is carried out. Data about height extracted from relief model is used as additional features in automated photointerpretation. 3.3 Determination and Registration e Current Changes on In order to reveal and register current forest fund changes caused by natural calamities (burns, windthrows, forest pathology, etc.) and economic activities (cuttings and or anthropogenic influence) automated comparison of planning-cartographic materials of forest management (for example forest management map schemes or forest stands plans) and or forest maps with aerial and scanner provided in

5 ASFIM. Into it forest mensuration characteristics and cartographic information including boundaries of plots and objects (burns, cuts, ete.) which emerged after latest forest management operations took place are entered. With help of television device or just from magnetic tape an aerial space photograph is entered into raster display system and visualized on screen. Interactive procedures of automated extraction of contours showing burns, cutting areas, etc. have been developed. In order to reveal and register current changes contours obtained in interactive mode should be compared with contour network determining forest state at time of last revision. To this end geometric correction of contours stored in cartographic data base of ASFIM is carried out by control points, as a result of which y are c~ordinated by photograph axes. The coordination by photograph is done with help of projection transformation, and by scanner image - through account and compensation of cylindrical distortions and earth's revolution with furr affine transformations. After geometric correction contours from cartographic data base are shown on screen of display system toger with photo image. Sometimes this procedure is done before automated interpretation of a photograph takes place. The possibility of combining on display system screen planning-cartographic materials and photographs makes it possible not only to determine quantitative characteristics of changes (for example volume of burnt timber, violation of major cutting regulations, etc.), but in some cases also gives interpreter additional information which helps to considerably improve reliability of interpretation process (for example degree of forest combustibility, land categories, etc.). The experience of work with ASFIM has shown that joint processing of digital cartographic and aerial space information makes it possible to solve a number of tasks dealing with processing of photographs in a new manner and with additional effect. 67