/// <summary>
/// Constructor for a feature extractor using Google Cloud Platform SDK, using a given annotator client,
/// optimized to be used with a batch of images.
/// </summary>
/// <param name="imageStream"></param>
/// <param name="client"></param>
internal GcpFeatureExtractor(Stream imageStream, ImageAnnotatorClient client)
{
SetRotation(SKCodec.Create(imageStream).EncodedOrigin);
var size = System.Drawing.Image.FromStream(imageStream).Size;
Width = size.Width;
Height = size.Height;
_image = Image.FromStream(imageStream);
_client = client;
}
Image ConvertBitmapToGoogleImage(Bitmap bitmap)
{
using (var bitmapStream = new MemoryStream())
{
bitmap.Save(bitmapStream, ImageFormat.Bmp);
bitmapStream.Position = 0;
return(Image.FromStream(bitmapStream));
}
}
/// <summary>
/// Constructor for a feature extractor using Google Cloud Platform SDK, optimized for analysing a single image.
/// </summary>
/// <param name="imageStream"></param>
/// <param name="credentialsPath"></param>
public GcpFeatureExtractor(Stream imageStream, string credentialsPath)
{
SetRotation(SKCodec.Create(imageStream).EncodedOrigin);
var size = System.Drawing.Image.FromStream(imageStream).Size;
Width = size.Width;
Height = size.Height;
var visionImage = Image.FromStream(imageStream);
_client = new ImageAnnotatorClientBuilder()
{
CredentialsPath = credentialsPath
}.Build();
_image = Image.FromStream(imageStream);
}
private async Task DoOCR()
{
try
{
string Identifer = Utility.RandomHex();
DebugLog.Log("Making OCR request [" + Identifer + "]");
if (!File.Exists(Properties.Settings.Default.apiKeyPath))
{
throw new FileNotFoundException("Keyfile not present at " + Properties.Settings.Default.apiKeyPath);
}
// Wait for rate limiter before starting the clock
GoogleAsyncStatic.rate.Check();
Stopwatch sw = new Stopwatch();
// Dump the provided image to a memory stream
var stream = new MemoryStream();
image.Save(stream, ImageFormat.Png);
stream.Position = 0;
// Load the stream as a gimage
GImage gimage = GImage.FromStream(stream);
// Make our connection client
ImageAnnotatorClient client = new ImageAnnotatorClientBuilder
{
CredentialsPath = Properties.Settings.Default.apiKeyPath,
}.Build();
// Ask for OCR
sw.Start();
var response = await client.DetectTextAsync(gimage);
sw.Stop();
// If we didn't get anything back
if (response.Count == 0)
{
_bigBox = OCRBox.ErrorBigBox();
_smallBoxes = new OCRBox[] { };
}
else
{
// First result is the big box
_bigBox = new OCRBox(response.First());
// Following results are the small boxes
_smallBoxes = response.Skip(1)
.Select(ann => new OCRBox(ann))
.ToArray();
}
_timeStamp = string.Format("{0:00}:{1:00}:{2:00}.{3:000}",
sw.Elapsed.Hours,
sw.Elapsed.Minutes,
sw.Elapsed.Seconds,
sw.Elapsed.Milliseconds);
isDone = true;
callback?.Invoke(this);
DebugLog.Log("Finished OCR request [" + Identifer + "]");
}
catch (Grpc.Core.RpcException e)
{
string url = "";
// Define a regular expression for repeated words.
Regex rx = new Regex(@"(http\S*)",
RegexOptions.Compiled | RegexOptions.IgnoreCase);
// Find matches.
MatchCollection matches = rx.Matches(e.Message);
if (matches.Count > 0)
{
url = matches[0].Groups[0].Value;
}
Form.Invoke(Form.SafeLogWorkerError, new object[] { e.Message, url });
} catch (Exception e)
{
Form.Invoke(Form.SafeLogWorkerError, new object[] { e.Message, "" });
}
}