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Hello FME experts,  

I am trying to use the Sentinel 2 AWS reader to get a series of Sentinel-2 images. I would like to get all images for specified date range, with cloud coverage below 30% and a specific Sentinel-2 tile (e.g. 33TVM). My input parameters look like in the attachment. However, running the translator produces the following error message:
Invalid search envelope specified:  
SENTINEL2AWS_1_SEARCH_ENVELOPE keyword must be followed by four numeric values (minX minY maxX maxY). Got '<Unused> <Unused> <Unused> <Unused>'

It obviously looks for search envelope with min and max X and Y. If these are specified then the tile parameters are ignored. The images are obtained for all tiles that cover the envelope. As my study area is at the overlap of two tiles, two images are obtained for a single date.  
FME workspace files for both cases are attached.  
Am I doing anything wrong? Is this a bug in reader?

Thanks for giving the FME 2017.1 beta a spin! I can tell that you were using a recent beta -- there were issues with Sentinel on AWS in 2017.0 and was going to suggest you try the beta.

That said, this does appear to be an issue. I know the team is working on this right now so will alert them to your scenario. I'll ask them to post back here when they have an update.

Thanks for your early feedback.

(Aside: My workflow that I've been encouraging is to use Sentinel on AWS in a FeatureReader, using the Search Envelope Intersects option. Then you just send in a polygon of your search area. Makes it easy if you already have your areas in a file or database already).

Thanks for identifying this issue, and sorry for the confusion/trouble you've had. As @daleatsafe said, we're currently working on this format, so the timing is perfect.

As an immediate workaround, you should be able to successfully run the translation by entering '0' for the search envelope values, rather than '<Unused>'. The 'Envelope' parameter should still be set to 'No'.

We will have this fixed for the release of 2017.1.

Thanks for giving the FME 2017.1 beta a spin! I can tell that you were using a recent beta -- there were issues with Sentinel on AWS in 2017.0 and was going to suggest you try the beta.

That said, this does appear to be an issue. I know the team is working on this right now so will alert them to your scenario. I'll ask them to post back here when they have an update.

Thanks for your early feedback.

(Aside: My workflow that I've been encouraging is to use Sentinel on AWS in a FeatureReader, using the Search Envelope Intersects option. Then you just send in a polygon of your search area. Makes it easy if you already have your areas in a file or database already).

@daleatsafe Support for reading Sentinel-2 and other satellite sources makes FME very exciting for Earth observation community.

 

 

You are reading my mind 🙂. I do have my study area as a Shape polygon and I am clipping the images in the next step. For the last couple of days I was trying to bring the polygon or its bounding box to the reader. Is your workflow available anywhere?

 

So here's the type of workflow I've been experimenting with. Get the boundingbox, pipe into a feature reader. On FMEWT we then also fetched an elevation model (via MapZenDownloader on FME Hub -- FME 2017.1 will have this as a reader too so you'd use 2 FeatureReaders. Then make a TIN and drape the image over top. Part of the flow is shown below. 2017.1 beta workspace attached for further inspiration.sentineldownload.fmw

Thanks for identifying this issue, and sorry for the confusion/trouble you've had. As @daleatsafe said, we're currently working on this format, so the timing is perfect.

As an immediate workaround, you should be able to successfully run the translation by entering '0' for the search envelope values, rather than '<Unused>'. The 'Envelope' parameter should still be set to 'No'.

We will have this fixed for the release of 2017.1.

Entering 0 for the search parameters does not change the error. I am using 20170404 - Build 17466 - WIN64.

 

Looking forward for the updated Sentinel Reader.

To improve its functionality, I would suggest to leave out the minimum cloud coverage. Images are mostly searched by maximum cloud coverage. I never had a reason to search for cloudy images 🙂.

Additional option might be seasonal data. E.g. Every year in Summer, or every year in August, or between 1 July and 31 August.

Looking forward for the updated Sentinel Reader.

To improve its functionality, I would suggest to leave out the minimum cloud coverage. Images are mostly searched by maximum cloud coverage. I never had a reason to search for cloudy images 🙂.

Additional option might be seasonal data. E.g. Every year in Summer, or every year in August, or between 1 July and 31 August.

Yes, the 2017.1 asks for maximum cloud coverage now.

 

Good idea re: the season...though the vocabulary may be tricky since our friends in the southern hemisphere have different ideas about what season is when then us Arctic dwellers. But we'll consider this for sure.

 

 

 

 

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