topic Re: How to create spatial index for Aerial Photos in Data Management Questions

How to create spatial index for Aerial Photos

JessiecarEsguerra — Sat, 20 Aug 2016 15:36:31 GMT

Hi Guys, I need help in building a spatial index of Aerial photos and have the Image Service project on the fly. Appreciate any ideas or inputs from anyone who has knowledge about this.

Thanks in advance.

- Jessiecar

Re: How to create spatial index for Aerial Photos

AdrianWelsh — Sat, 20 Aug 2016 19:05:58 GMT

Jessiecar,

Have you tried the Add Spatial Index geoprocessing tool?

Add Spatial Index—Help | ArcGIS for Desktop

Re: How to create spatial index for Aerial Photos

XanderBakker — Sat, 20 Aug 2016 23:31:01 GMT

Spatial indexes are for featureclasses (see An overview of spatial indexes in the geodatabase—ArcGIS Help | ArcGIS for Desktop ).

If you have an image service, your raster data will probably be in a mosaic dataset. In a mosaic dataset you will create overviews (Build Overviews—Help | ArcGIS for Desktop ) and there are other tools available to enhance the performance of the mosaic dataset (see also Add Rasters To Mosaic Dataset—Help | ArcGIS for Desktop and other tools in the Mosaic Dataset toolset. You can load the raster and they will be projected to the configured spatial reference.

Re: How to create spatial index for Aerial Photos

JessiecarEsguerra — Mon, 22 Aug 2016 09:14:14 GMT

I didn't tried it yet just like what Xander mentioned, it says that "Add Spatial Index" is for shape file, file geodatabase, or enterprise geodatabase feature class.

But thanks, I might try exploring it too to see if there's something I could use it for.

Re: How to create spatial index for Aerial Photos

JessiecarEsguerra — Mon, 22 Aug 2016 09:17:05 GMT

Hi Xander, thank you, I will try this and you are correct that I have Mosaic Dataset but it only contains those georef images.

So if I will be adding those non-georef images on my mosaic dataset, there is a way I could have those projected on the fly? I have a metadata for all Aerial photos that I have - both georef & non georef images.

Thank you so much for your time.

Re: How to create spatial index for Aerial Photos

DanPatterson_Retired — Mon, 22 Aug 2016 09:35:13 GMT

non-georeferenced images still need georeferencing, otherwise their place is space will remain unknown and cannot be appropriately integrated with georeferenced data

Re: How to create spatial index for Aerial Photos

JessiecarEsguerra — Mon, 22 Aug 2016 10:36:44 GMT

Thanks Dan.

Do you know any way to georeference by batch? Doing it one by one will take forever and that is not feasible to the project I am working with.

Much appreciated. Thanks!

Re: How to create spatial index for Aerial Photos

Anonymous User — Mon, 22 Aug 2016 11:29:01 GMT

Hello,

If you Aerial images are well processed(georeferenced , orthorectified ) then you are able to create spspatia lndexes and view to use in further analysis.

In ArcMAP not seen or use batch Georeferencing tool.

Thanks.

Re: How to create spatial index for Aerial Photos

JessiecarEsguerra — Mon, 22 Aug 2016 12:00:19 GMT

Hi Avinash, unfortunately, I have Aerial images that are not georeferenced.

Re: How to create spatial index for Aerial Photos

XanderBakker — Mon, 22 Aug 2016 12:05:44 GMT

Assuming that the aerial photos cover different areas and if they really do have any spatial reference, you will not be able to georeference them if you do not have any additional information. In case you have a file with the location of each photo there are ways to georeference them in batch (using for instance some Python code), but it seems very strange that the photo came without any georeference information. There are algorithms that search for matching points in overlapping photos and can mosaic them together (like for instance is done in Drone2Map). Is it possible to add a screenshot of the properties of a photo or share one of those photos to see if this is really the case?

Re: How to create spatial index for Aerial Photos

JessiecarEsguerra — Tue, 23 Aug 2016 03:31:25 GMT

The georeference information is available as the metadata for all Aerial photos I have - both georeferenced & non-georeferenced images.

Here's a sample screenshot of an Aerial Photo that is not georeferenced.

Will try to use Phyton code in georeferencing by batch.

Thank you Xander.

Re: How to create spatial index for Aerial Photos

JessiecarEsguerra — Tue, 23 Aug 2016 03:40:21 GMT

Another problem I have here, as you can see on the sample image, the GCPs is not the current extent of the Aerial Photo. It require cropping before I can proceed in georeferencing by batch using Python code.

Any other inputs related to this, I would appreciate.

Thanks everyone!

Re: How to create spatial index for Aerial Photos

XanderBakker — Tue, 23 Aug 2016 11:31:06 GMT

Hate to tell you, but you are looking at a lot of manual labor...

Re: How to create spatial index for Aerial Photos

NeilAyres — Tue, 23 Aug 2016 14:18:28 GMT

That's a really old style aerial photo. Don't see many of them around these days. Xander is absolutely correct, there is no one click solution to get these geo-referenced easily.

But have you considered using more modern sources of aerial imagery. Or do these photos have some sort of historical interest?

Re: How to create spatial index for Aerial Photos

JessiecarEsguerra — Tue, 23 Aug 2016 23:36:14 GMT

You are right Neil, I need historical Aerial photos along with the recent ones. And I don't have problems with recent coz all of those are georeferenced.

That's what I'm trying to resolve Xander, finding a possible solution to not do a lot of manual work.

Re: How to create spatial index for Aerial Photos

JessiecarEsguerra — Thu, 25 Aug 2016 07:37:29 GMT

Good news. Me and my team were able to find other resources like gdal & metalab to do cropping of aerial to have the GCPs as the extent of each Aerial photo.

From there, once the Aerial photos are cropped, we can georeferenced these images by batch using Python or other script.

Thanks everyone for all the inputs.

Re: How to create spatial index for Aerial Photos

XanderBakker — Thu, 25 Aug 2016 12:02:24 GMT

Hi Jessiecar Esguerra , I don't want to ruin your day, but I don't think that it will be possible. Cropping the images in batch is no problem. What really is the hardest job is to find the control points and align the raster with these control points. See Fundamentals of georeferencing a raster dataset—Help | ArcGIS for Desktop

How are you planning to use a python script to do that part of the job?

Re: How to create spatial index for Aerial Photos

JessiecarEsguerra — Fri, 26 Aug 2016 01:46:59 GMT

HI Xander, I have the metadata for all my Aerial Photos which contains all the control points. I can use the image filename to link with the metadata and then assign those control points programmatically.

Re: How to create spatial index for Aerial Photos

XanderBakker — Fri, 26 Aug 2016 02:06:43 GMT

That is good to know! In what format are the control points stored? And how are they defined (rows, cols and related coordinates)?

Re: How to create spatial index for Aerial Photos

JessiecarEsguerra — Fri, 26 Aug 2016 03:20:52 GMT

For the control points I have two formats available in the metadata, the DMS & Decimal Degrees.