Hello, I’m hoping someone can help me cuz I’m going a little bit crazy after many, many failed attempts… (I’m a noob so am out of my depth here…)
I want to use Azure to do an OCR read on a local image in my (Android) app folder. Azure doc says to read local images you put the binary image data in the HTTP request body and set content format octet-stream.
I’m using NativeGallery to take a screenshot on the phone and then I copy it to the local app folder using System.IO.File.Copy. I then convert the local image into a texture, then convert to bytes. I use WWWForm to create a web form, which Unity says to use for uploading images. I pass the form into my Post request but nothing happens… I’ve put what I think are the relevant bits below.
Thank you 
private IEnumerator TakeScreenshotAndSave() //take a screenshot and save it
{
yield return new WaitForEndOfFrame();
Texture2D ss = new Texture2D(Screen.width, Screen.height, TextureFormat.RGB24, false);
ss.ReadPixels(new Rect(0, 0, Screen.width, Screen.height), 0, 0);
ss.Apply(); // takes screenshot and stores in texture
// save image to phone gallery. copy image to local app folder
NativeGallery.Permission permission = NativeGallery.SaveImageToGallery(ss, "TESTfolder", "image.png", (success, path) => System.IO.File.Copy(path, Application.persistentDataPath + "/SavedImage" + ".png", true));
Debug.Log("Permission result: " + permission);
ScreenshotLocation = (Application.persistentDataPath + "/SavedImage.png"); // path to screenshot
ScanImageWithOCR(); // call the OCR function
Destroy(ss); // To avoid memory leaks
}
////////////////////////////////////
void ScanImageWithOCR() // convert the image to bytes and upload to Azure
{
// setup the request header
RequestHeader clientSecurityHeader = new RequestHeader
{
Key = clientId,
Value = clientSecret
};
// setup the request header
RequestHeader contentTypeHeader = new RequestHeader
{
Key = "Content-Type",
Value = "application/octet-stream"
};
var rawData = System.IO.File.ReadAllBytes(ScreenshotLocation); //read the screenshot at this path and store in var rawData
var screenshotTexture = new Texture2D(Screen.width, Screen.height, TextureFormat.RGB24, false); // Create a texture the size of the screen, RGB24 format
screenshotTexture.LoadImage(rawData); // put var rawData into new texture
byte[] bytes = screenshotTexture.EncodeToPNG(); // convert texture to byte array
Destroy(screenshotTexture); // delete texture
// Create a Web Form containing bytes array
WWWForm form = new WWWForm();
form.AddField("frameCount", Time.frameCount.ToString());
form.AddBinaryData("", bytes, null, null);
// send a post request with bytes contained in WWWForm
StartCoroutine(RestWebClient.Instance.HttpPost(baseUrl, form, (r) => OnRequestComplete(r), new List<RequestHeader>
{
clientSecurityHeader,
contentTypeHeader
}));
////////////////////////////////////////////////
public IEnumerator HttpPost(string url, WWWForm form, System.Action<Response> callback, IEnumerable<RequestHeader> headers = null)
{
using (UnityWebRequest webRequest = UnityWebRequest.Post(url, form))
{
if (headers != null)
{
foreach (RequestHeader header in headers)
{
webRequest.SetRequestHeader(header.Key, header.Value);
}
}
webRequest.uploadHandler.contentType = defaultContentType;
// webRequest.uploadHandler = new UploadHandlerRaw(System.Text.Encoding.UTF8.GetBytes(bytes));
yield return webRequest.SendWebRequest();