APEX Usage Sample:

AzureService.azureWrapper uow = AzureService.storageDetails();

system.debug(uow);

Datetime dt = Datetime.now();

Attachment att = [select name, contentType, bodylength, body from attachment where id ='some id here'];

uow = AzureService.signedSignature(uow, dt, att.name, att.contentType, att.bodyLength);

system.debug(uow);

Boolean result = AzureService.uploadToAzure(uow,att.body);

system.debug(result);

VF uses the Azure js library generated as per instructions here

Check out the the script tag in the VF page to understand.