Given article is devoted the extremely actual problem of use of the scanned or photographic copies of paper materials. In anybody any more does not cause doubts what to create floor plans for the computer faster and more conveniently, than to perform the same work by means of a pencil and a ruler. But what to do with plans which are already created and are stored in a paper kind?
Many consider as unique way of their use rendering such plans anew, already in an electronic (vector) kind. At the best scanned the (raster) plan is used as a substrate at creation of the vector plan.
Program PlanTracer SL allows to reduce at least in 10 times time of creation of the vector plan on the basis of raster, and than there will be a plan more difficult, the difference will be especially notable. We will look, as it to achieve.
That the paper original “has got to the computer” preliminary it is required either to photograph it, or to scan. It is very important process. Considerable losses of quality of documents at scanning – a consequence of use of the poor-quality equipment or incorrect technology were one of the reasons on which the vectoring of plans has not received due distribution.
The basic characteristic of the raster document – its permission, that is quantity of points to inch (dpi). For correct processing in the course of a vectoring the document should have the permission not less than 300 dpi. Besides the permission, quality of a copy is defined also by such indicators, as contrast and presence of distortions of a raster.
The best quality of a raster copy provide professional large-format scanners – in this case any additional processing is not required and it is possible to start a vectoring at once. Unfortunately, because of high cost the similar equipment is far not in each organisation.
Cheaper, but also more labour-intensive process assumes scanning of the big document in parts with use, for example, the scanner of format А4. Ways of the further processing of the image will be considered more low.
Has most difficult put is with photographing. We will admit, at work it is planned to use the camera of an average price category with a matrix of 7 Mp (7 million points). To compare the camera and the scanner, we will calculate the maximum size of a fragment which can be photographed for reception of is minimum admissible permission. We take a square root from total number of points and we receive number of points on one party – approximately 2600. We divide into the demanded permission – 300 dpi. Result – the maximum length of the party of a fragment inches. It is equal 8.6 inches, or 218 mm. Thus, even with use of the modern camera the maximum fragment which can be photographed with the quality close to quality of the scanned image, is a sheet A4. In addition, at photographing there is a number трудноустранимых defects (for example, spherical distortions of a picture or the low-contrast lines generated by problems at focusing).
The conclusion is obvious: at the decision of problems of a vectoring floor plans the camera hardly probable will appear worthy alternative to the scanner.
In general the economy at an equipment choice can negatively affect quality of copies that will make senseless the further work on a vectoring of the received rasters.
Let's consider crosslinking of fragments
i.e. how from several fragments by means of tools PlanTracer SL receive the uniform raster image the floor plan.
First of all we eliminate the warps which have arisen at scanning. One of fragments is for this purpose chosen and we start a command To eliminate a warp automatically
. Having analysed the image, the program levels it concerning horizon.
The remained fragments it is levelled rather already processed, having taken advantage of a command to Level. It is for this purpose specified two any points which are present on both fragments, thus the second raster simultaneously is scaled and turns on a necessary corner concerning the first.
In end it is sewed all rasters by means of a command The new raster from chosen
Let's consider binarization
: the vectoring can be made only on the monochrome image (the raster image consisting of black points of the information and white points of a background) if as a result of scanning the colour image or the image in gradation grey is received, it is necessary to translate it in a monochrome kind, using a command binarization
Command parametres are set so that the received plan consisted of well distinguishable lines with a minimum quantity of ruptures. Thus it is necessary to supervise a thickness of lines that, on the one hand, there were no ruptures, and with another – close located thin lines did not merge in one (for example, on thin walls). As a result of command application it is received the monochrome image.
Let's consider a vectoring
. First of all before the vectoring beginning it is required rescale the raster image. In PlanTracer SL the convenient command of fast scaling of rasters is realised. The based problem – to achieve conformity of the sizes which have been put down on the plan, and the real sizes of the raster image.
The following stage – preparation of library for recognition. It is necessary to consider following moments:
- walls and ladders are distinguished automatically so for their recognition it is not required to create library templates. Moreover, presence of templates of walls and ladders can worsen result;
- it is not necessary to create an element template if it meets on the plan less than ten times.
To create a template for recognition, it is required to draw by means of tools of vector drawing over a raster an element as much as possible similar on required (the example of a template of a window is shown in drawing).
After that we add the created element in library.
Preparation is finished. Further from us is required to press only the button Vectoring
– after the short analysis of the drawing the program will create vector parametrical the floor plan consisting of objects of windows, doors etc.
At correct adjustment which occupies no more than ten minutes, and taking into account all operations presented above, it is possible to receive the plan, approximately on 95% coinciding with the raster. The others can be finished of 5% by means of means of drawing and the editing, presented in the program.
Time necessary for copying of the plan, depends on the sizes of the raster image: the more objects, the this process longer lasts. The vectoring occurs much faster, and time of its performance is not connected with the sizes of the plan.
Thus, PlanTracer sl allows to use effectively in work paper floor plans, schemes, topographical and maps and sharts.
By means of program tools it is possible:
- Considerably to raise quality of the raster image received after scanning;
- quickly to make necessary changes to the scanned drawing;
- simultaneously and effectively to work with a raster and vector drawing, as required translating fragments of the document or all drawing entirely in the vector form;
- completely vectorize the scanned image.
Result of recognition – intellectual vector model the floor plan, consisting of objects (walls, windows, doors, the equipment etc.).
It is necessary to notice that program PlanTracer SL besides work with the scanned images also allows to work with floor plans, with ground plans, to count the areas, to make out plans, to co-operate with an external database.