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  2. If you have access to ArcGIS, using "Warp" in modelbuilder or python could automate your process.
  3. Yesterday
  4. bmp.HorizontalResolution , bmp.VerticalResolution "HorizontalResolution and the VerticalResolution are pixel per inch
  5. I read it but it again gives in pixel. It seems I must find a way to convert pixel size to pixel resolution value. humm?
  6. Sorry my bad take a look
  7. Hi, Thanks very much but this gives the results in pixels not in cm?How can I convert it to cm?
  8. Hi everyone, i have the massive which i should complete in 1 month about the subjected topic. I have 1000 topo maps and i need your contribution how i can automate this process as much as i can. Thanks in advance. Tapatalk kullanarak iPhone aracılığıyla gönderildi
  9. System.Drawing.Image img = System.Drawing.Image.FromFile (@"my image.jpg") now you have img.Width and img.Height
  10. Hi again, Can you please give some information about calculation of x,y in cm?How can I calculate them?Should I use the camera's focal lens?
  11. Last week
  12. I would like to get opinions and experience about GIS servers. Lets assume that we need to host our data and use them internally as well as sell them to others. "Everyone" is using ESRI ArcGIS Server. But there is also GeoServer and MapServer (these need other software to bridge the gap between ESRI). ESRI option is expensive but others lack GUI, ease of use and some functionality. So: - What would you suggest me to consider in choosing between options? - How they compare (management, functionality, administration)? Now there is ArcGIS Enterprise. So feature looks more like ArcGIS Pro together with Portal? As I understand than anyone connecting to Portal needs license (or only those that want to publish something)? Could you share your experience? How whole Portal experience compares to open source alternatives (GeoServer with GeoNode with OpenLayers)? There is page at: Which country national cartography and topography agencies are using free or open source GIS software at the back end? Could you share knowledge and experience of why should I choose to buy ArcGIS for Enterprise instead of using free alternatives?
  13. Could you share your experience programming GIS software extensions. How about web back end - Java, PHP, .NET? What language should complex system use? What is the best language for developing extensions for specific software: - QGIS (Python) - ArcGIS for Desktop (ArcObjects, ArcPy, .NET, Java) - ArcGIS Pro (ArcPy, .NET) ? What about functionality, speed? What tools do you use: - IntelliJ IDEA? - Visual Studio for .NET? - What Python IDE? What is going to be used in feature? .NET is not going away for a while. Python is increasingly used but from time to time there are things or extensions that doesn't work.
  14. I would like to get opinions and experience about GIS databases. In this case ones that are used for large topography, cartography and related dataset creation and publishing. So lets imagine that we have the following databases to choose from (you can freely add others, that have native GIS types and ESRI support): Oracle (PL/SQL) - native GIS or ESRI option - wide applications, very expensive SQL Server (T/SQL) - native GIS or ESRI option - easy administration, expensive PostgreSQL (PL/pgSQL) - native GIS or ESRI option - hard configuration, cheap (support) In those we can build GIS datasets without ESRI price tag and with it if choose to buy ESRI licenses. All three of them have database side language for making custom procedures, functions that help organize things. A lot of people in my country have invested in Oracle database knowledge and certification. So it is easy (there is always lack of people with programming, database and administration skills for certain amount of salary) to find corresponding people. But that all comes with the price tag (Oracle is not AIO, for every additional feature that it alternatives is already included you have to pay). Lets work under assumption that there are equal number of professionals for every database. There are two other big names: PostgreSQL and SQL Server (and probably DB2). From the pricing perspective both are at least times cheaper. As I understand than there are specific aspects to each of them. How do they compare (why should I choose one over the another): - Could you name the most important aspects? - How common are geometry errors? What other problems have you experienced (like ESRI ST_Intersects errors or other)? - What is the best tooling for administrating and developing in these databases (price, ease of use, functionality - Oracle SQL Developer Studio, MS SQL Server Management Studio, pgAdmin, TOAD)? - What about security - how easy is configuration for novices? - How hard is it to properly configure and administrate specific database? - What can I do with data if I use ArcGIS, and what if I use QGIS? - What about ArcGIS Geodatabases vs native GIS data types - availability of tooling (ArcGIS cant edit PostGIS)? - Would migration be worth it and if you have experience what was the hardest thing, given pricing (migrating code)? I do look towards PostgreSQL because of pricing. What would I miss? How future would look like in databases? Ideally those that have experience with at least two of the mentioned databases (one preferably being PostgreSQL) would respond.
  15. you have to move center of your image which is not georeferenced to the exact location, this is the movement problem and your question about pixels and cm, think about a resolution (100,100) with 2 different pixel sizes 1 - 1*1 cm2 2 - 1000*1000 cm2 do you think calculation in pixels is correct now?
  16. thanks very much. I have to search more to find calculations and equations but why the x,y of center of image is in cm?should not it be on pixels?On the other side I have the exact lat and lon of the center of image what about it?
  17. until
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  18. I don't have any documents, unfortunately. convert your image into an array. find the x y of the center of the image for example (10 cm, 12 cm) convert them to degrees dx = Long - Xdeg dy = Lat - Ydeg A = move all the cells with this dx and dy B = rotate A (flight azimuth) C = scale B based on flight height and .. (i'm not sure about dz)
  19. Thanks, Can you please share some documents of using those parameters to georefrence?and also please explain a bit more about delta x, y and z...Why I need them?
  20. As far as I know, yes you can you have image size, camera elevation, camera focus length, so you can solve Scale problem, you have flight azimuth, so you can solve Rotation problem if you have delta X, delta Y and delta Z, so you can solve Movement problem.
  21. Hi,If we consider those information as what you have suggested Can I georefrence it using those data?or it is not possible?
  22. I dont know about that. But there is another angle on the top right of the image. I dont remember these courses but my guess is information on top are about flight and on the bottom are about camera settings!!
  23. Hi Yousef, Yes It is the elevation of camera is 1111.1 meters but I am not sure about azimuth. could it be the angle of horizontal image?
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  25. Hi, Pixel size will solve the problem of scale, How about the rotation problem? Is that Azimuth angle? It seems like an imagery from a water body with an elevation near to zero. do you have the elevation of the camera (1114.1 meters?)? and size of the image? is it tilted?
  26. Dear rahmansunbeam, Thanks for your answer, you know the only data that I have are as this image. I think I can not find 4 points as I dont have any other benchmarks except what is in center of the image. I think If I can find pixel size on earth I can find other points but the rotation is the case here. The image that I have is uploaded in above link. Can you please take a look at it and give me some suggestions?thanks
  27. You have to identify 4 more points from the xy location. Just set a fixed euclidean distance from that point and draw four other point who have same distance from their neighbors. The distance should not exceed the image size. Than let the program identify their xy locations. More ideas are here - Georeferencing aerial photos when only centroid is known using ArcGIS for Desktop or ERDAS Imagine? I think you cannot do it with elevation.
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