What is metadata? How do I create a metadata and how do I associate it to a Cloud target using Vuforia?

I modified sample CloudRecog code for my own code. I created cloud database and get AccessKeys then copied this keys to CloudReco.cpp file. What should i use for metadata. I didn't understand this. Then when i was reading sample code i saw this line: private static final String mServerURL = "https://ar.qualcomm.at/samples/cloudreco/json/". How to get my metaData url?

Solution

EDIT: this is in response to the first part of your question,: "What should i use for metadata" (not the second part about how to find the URL)

Based on their documentation (https://developer.vuforia.com/resources/dev-guide/cloud-targets):

The metadata is passed to the application whenever the Cloud Reco target is recognized. It is up to the developer to determine the content of this metadata – Vuforia treats it as a blob and just passes it along to the application. The maximum size of the uploadable metadata is 150kByte.

I added some debugging in their CloudRecognition app and saw that the payload (presumably the meta-data) they return when "recognizing" an image is:

{
    "thumburl": "https://developer.vuforia.com/samples/cloudreco/thumbs/01_thumbnail.png",
    "author": "Karina Borland",
    "your price": "43.15",
    "title": "Cloud Recognition in Vuforia",
    "average rating": "4",
    "# of ratings": "41",
    "targetid": "a47d2ea6b762459bb0aed1ae9dbbe405",
    "bookurl": "https://developer.vuforia.com/samples/cloudreco/book1.php",
    "list price": "43.99"
}