Introduction to AzureCognitive

Resource Manager interface

AzureCognitive extends the class framework provided by AzureRMR to support Cognitive Services. You can create, retrieve, update, and delete cognitive service resources by calling the corresponding methods for a resource group.

az <- AzureRMR::get_azure_login()
sub <- az$get_subscription("sub_id")
rg <- sub$get_resource_group("rgname")

# create a new Computer Vision service
rg$create_cognitive_service("myvisionservice",
    service_type="ComputerVision", service_tier="S1")

# retrieve it
cogsvc <- rg$get_cognitive_service("myvisionservice")

# list subscription keys
cogsvc$list_keys()

Client interface

AzureCognitive implements basic functionality for communicating with the Cognitive Services REST API. The main functions are cognitive_endpoint, which creates an object representing the endpoint, and call_cognitive_endpoint to perform the REST calls.

# getting the endpoint from the resource object
endp <- cogsvc$get_endpoint()

# or standalone (must provide subscription key or other means of authentication)
endp <- cognitive_endpoint("https://myvisionservice.cognitiveservices.azure.com/",
    service_type="ComputerVision", key="key")

# analyze an image
img_link <- "https://news.microsoft.com/uploads/2014/09/billg1_print.jpg"
call_cognitive_endpoint(endp,
    operation="analyze",
    body=list(url=img_link),
    options=list(details="celebrities"),
    http_verb="POST")

The latter call produces output like that below (truncated for brevity).

$categories
$categories[[1]]
$categories[[1]]$name
[1] "people_"

$categories[[1]]$score
[1] 0.953125

$categories[[1]]$detail
$categories[[1]]$detail$celebrities
$categories[[1]]$detail$celebrities[[1]]
$categories[[1]]$detail$celebrities[[1]]$name
[1] "Bill Gates"

$categories[[1]]$detail$celebrities[[1]]$confidence
[1] 0.9999552