Qin Shuang Pu Hanyong
(Geological Museum of Henan Province)
Abstract The digitization of scans has evolved from the 8th Five-Year Plan of the Ministry of Mines and Geology to the 12th Five-Year Plan of the Ministry of Land and Resources, and the hardware and software we apply have changed greatly. The software and hardware we apply have changed a lot. In view of the impact of hardware and software changes on the current digitization work, and the technical problems in digitization work, we are faced with how to do a good job of scanning and digitization work with the times.
Keywords Digitization Status quo Problems Countermeasures ANATech EAGLE SLI3840 Scanner SCANSMITH PREDITOR Software colortracsmartlf GX Series Large Format Scanner Adobe Photoshop Software
1 Status quo of digitizing work
Geological drawings are very different from general engineering drawings. The latter is not affected by poor accuracy because it is labeled with dimensions on the drawing, but geological drawings use a scale, so some of the drawings require high accuracy. The root of this problem is the accuracy of the scanner. To this end, the "Eighth Five-Year Plan" period, the choice of the United States INTERGRAPH ANATech EAGLE SLI3840 scanner, can meet the accuracy requirements, a better solution to the problem of elimination of blue, data compression.
1.1 Accuracy
The scanning accuracy of the fundamental is the accuracy of the scanner. At that time selected the United States INTERGRAPH ANATech EAGLESLI3840 scanner, its "skewed distortion" factory specifications for the 0.1%, on the standard A0 drawings, with the scanner input, the horizontal error can be controlled within 0.5mm, the vertical error can be controlled within 0.8mm. 0.8mm.
1.2 Blue elimination
Most of the old data kept by the Geological Data Bank are blueprints, and because of the long time of preservation, the background color of the drawings is very dark, with a small contrast, which must be eliminated when the drawings are input. Selected ANATech EAGLE SLI3840 scanner, can be a good solution to the problem of blue.
1.3 Data compression
The application of data compression technology is the key to ensure the feasibility of this project. It is necessary to select the most suitable compression format for geological maps.
For geological maps, after a lot of experiments and statistics, and considering the future data exchange, Tiff CCITT group 4 FAX format, which is more general and belongs to the international standard, was finally selected as the official data format for CD-ROM storage. It is also one of the most widely used image formats, which uses a special lossy compression algorithm to remove image colors that are not easily detected by the human eye, so as to achieve a larger compression ratio.
See the table below for a comparison.
Proceedings of the Eighth National Symposium on Geological Archives
1.4 Editing Software
After scanning and forming the image, SCANSMITH PREDITOR is used to edit the image. This software is powerful image processing software that can edit binary images, grayscale images, and 8-bit or 24-bit color images, and can call up or edit files of tens of meters in length (mainly binary images) and tens of megabytes or hundreds of megabytes in capacity obtained from the scanner scans, and the software starts up fast and runs very quickly. At the time, the ANATech EAGLE SLI3840 scanner and the SCANSMITH PREDITOR software were the best combination.
2 workflow
The old geological information first repair, and then select the scanning parameters, select the parameters of the way to eliminate blue, scanning, skewing, rotating, preliminary editing, checking, denoising, removing edges, jigsaw puzzles, planting the word against the errata, quality checks, library building, CD-ROM production. The library building method adopts electronic file naming and three-level catalog production method. This workflow has been used until today.
3 digitization work facing problems
digitization work has developed to the present day, we use the scanning and digitizing equipment has changed a lot, ANATech EAGLESLI3840 scanner has now been discontinued, accessories are also difficult to buy, so only the replacement of scanning equipment.
Because the equipment is different, the scanning software is also different, the scanning software is SCANSMITH SCAN, editing software is SCANSMITH PREDITOR. then now the new scanner comes with the scanning software, but does not come with its own editing software, scanning with the new scanner comes with the software, using SCANSMITH PREDITOR post-editing when the scanner is scanned. PREDITOR, you will encounter problems when editing later.
3.1 Currently commonly used large scanners and technical parameters
In recent years, the provinces engaged in scanning and digitizing the scanning equipment are mainly: ColorGiant, contex, Nitto, colortrac smartlf GX and other series of large-format scanners. Our museum is now using colortrac smartlf GX+T56 scanner, the specific parameters are as follows:
Proceedings of the Eighth National Symposium on Geological Archival Materials
3.2 Problems with SCANSMITH PREDITOR editing
When we use colortrac smartlf GX+T56 scanner comes with the software after scanning, with SCANSMITH PREDITOR to do editing work, the biggest problem is brought about by deskewing, the frame appears jagged. The rotation angle is different, the result is different.
Eighth National Symposium on Geological Archives
Through the above comparison, it is found that: the larger the angle of rotation, the denser the jaggedness; the more the number of rotations, the jaggedness will become more, and the image becomes blurred. However, the rotation is a multiple of 90, both counterclockwise and clockwise, so you can't see the change with the naked eye.
4 current digitization countermeasures
For the work of such problems, had to give up the SCANSMITH PREDITOR software, the use of Adobe Photoshop software, no matter how to turn, there is no such problem. Specific operations are as follows.
4.1 Measurement Angle
First of all, open a picture, and then select the toolbar in the "Measurement Tools", as follows:
Eighth National Geological Archives Symposium Proceedings
At the beginning of the picture frame, from left to right, hold down the left mouse button, and the frame of the parallel direction! Drag the mouse to the end of the right end of the picture frame, as shown in the following figure (in order to facilitate observation, the drag trajectory did not overlap with the picture frame and maintain a certain distance).
Eighth National Symposium on Geological Archives
4.2 Rotate the canvas
Then click "Image" - "Rotate Canvas" - "Any Angle" - "Rotate Canvas" - "Rotate Canvas" - "Rotate Canvas" - "Rotate Canvas".
Anthology of the Eighth National Symposium on Geological Archives
The above automatically measured angle value will automatically appear in the dialog box, according to the screen prompts (the value of the automatically measured angle is 5 degrees), tap "OK", then the image is rotated by 5 degrees, i.e. horizontally. Then crop the edges, store, and process the image in Adobe Photoshop according to the workflow, you can get satisfactory results.
5 Conclusion
Skewing is a necessary step in scan digitizing. After scanning an image with a scanner other than the ANATech EAGLE SLI3840, rotating the image with the SCANSMITH PREDITOR creates a jagged shape of varying sizes, or misalignment.
In terms of the current scanning and digitizing work, the scanner has changed, in the absence of matching software to deal with the image, we have to choose the appropriate third-party software to deal with the image, is a performance with the times.