public async Task <IDictionary <string, float> > GetPredictionAsync(Stream stream, Guid projectId, Guid iterationId)
{
if (stream == null)
{
throw new ArgumentNullException($"{nameof(stream)} cannot be null");
}
if (projectId == Guid.Empty || iterationId == Guid.Empty)
{
throw new ArgumentException($"{nameof(projectId)} and/or {nameof(iterationId)} cannot be empty");
}
var predictions = new Dictionary <string, float>();
try
{
var result = await _endpoint.PredictImageAsync(projectId, stream, iterationId);
var tags = (from p in result.Predictions select new { p.TagName, p.Probability }).OrderByDescending(p => p.Probability);
foreach (var t in tags)
{
predictions.Add(t.TagName, (float)t.Probability);
}
return(predictions);
}
catch (Exception ex)
{
return(predictions);
}
}
public async Task <string> Analyze(byte[] image, string projectId)
{
var imageStream = new MemoryStream(image);
var prediction = await _client.PredictImageAsync(new Guid(projectId), imageStream);
return(prediction.Predictions.FirstOrDefault().TagName ?? "None");
}
private async void Button_Clicked(object sender, EventArgs e)
{
// 写真撮影
// Cameraを起動して写真を撮影（Plugin任せ）
var file = await CrossMedia.Current.TakePhotoAsync(new StoreCameraMediaOptions
{
DefaultCamera = CameraDevice.Front,
AllowCropping = false,
PhotoSize = PhotoSize.Medium,
});
// 撮影しなかった場合は何もしない
if (file == null)
{
return;
}
// 画像を表示
image.Source = ImageSource.FromStream(() => file.GetStream());
try
{
// CustomVision用クライアント準備
// ApiKeyにはPredictionKeyを指定
// Endpointにはhttps://southcentralus.api.cognitive.microsoft.comを指定
var client = new CustomVisionPredictionClient()
{
ApiKey = PredictionKey,
Endpoint = Endpoint
};
// 画像を解析(IterationIDを指定しないとうまくいかない)
var resul = await client.PredictImageAsync(Guid.Parse(ProjectID), file.GetStream(), iterationId : Guid.Parse(IterationID));
// 結果取得
var prediction = resul.Predictions.FirstOrDefault();
await DisplayAlert("判定結果", $"タグ名: {prediction.TagName} Probability: {prediction.Probability}", "OK");
}
catch
{
await DisplayAlert("判定結果", $"エラー", "OK");
}
}
private async Task <VisionAPI.Contract.Tag[]> Prediction(Stream stream)
{
try
{
CustomVisionPredictionClient endpoint = new CustomVisionPredictionClient()
{
ApiKey = PredictionKey,
Endpoint = SouthCentralUsEndpoint
};
var result = await endpoint.PredictImageAsync(projectId, stream);
var pistols = result.Predictions.Where(p => p.TagName == "pistol" && p.Probability > 0.75).OrderBy(e => e.Probability).ToList();
if (pistols.Count > 0)
{
ServiceClientCredentials credentials = new TopicCredentials("jVyvj5pqIZeR1t/xgBAjhkCd3UfLNkJV89Smpsm6XeE=");
var client = new EventGridClient(credentials);
var eventGridEvent = new EventGridEvent(Guid.NewGuid().ToString(), "FirearmDetected", pistols.First(), "FirearmDetected", DateTime.UtcNow, "1");
// Publish the events
await client.PublishEventsAsync("km-firearm-topic.eastus2-1.eventgrid.azure.net", new[] { eventGridEvent });
}
return(pistols.Select(p => new VisionAPI.Contract.Tag()
{
Name = $"{p.TagName}: ${p.Probability:P1}"
}).ToArray());
}
catch (Exception e)
{
return(new[] { new VisionAPI.Contract.Tag()
{
Name = ""
} });
}
}
