/// <summary>
/// Send the LPImageData to the NodeJS and the return the resulting OpenALPR data with callback
/// </summary>
/// <param name="pImageData">Location and the image data</param>
/// <param name="detectedPlatesCB"> <see cref="DetectedPlatesHandler"/> </param>
/// <returns><see cref="Task"/></returns>
public async Task Detect(LPImageData pImageData, DetectedPlatesHandler detectedPlatesCB)
{
StorageFolder outputFolder = ApplicationData.Current.LocalFolder;
int r = Interlocked.Increment(ref totalProcessed);
DateTime dt = DateTime.UtcNow;
string id = dt.ToString("MM/dd/yyyy hh:mm:ss.fff tt"); /*create unique file name based on the current date and the count*/
id = id.Replace(" ", "");
id = id.Replace("/", "");
id = id.Replace(":", "");
id = id.Replace(".", "");
id += r;
StorageFile outputFile = await outputFolder.CreateFileAsync(@"test_pics_out\" + id + ".jpg", CreationCollisionOption.ReplaceExisting);
SaveSoftwareBitmapToFile(pImageData.lpImage, outputFile);
var openALPR = new Task <OpenAlprData>(() => UseOpenAlpr(outputFile, pImageData));
openALPR.Start();
openALPR.Wait();
var openALPR_result = openALPR.Result;
detectedPlatesCB(openALPR_result, pImageData.lpImage, (openALPR_result != null) ? 0 : 1);
}
/// <summary>
/// Send the LPImageData to the NodeJS and then processes it. Which is just taking the most confident plate that is been detected by the OpenALPR
/// </summary>
/// <param name="lpImageData"> Location and the image data </param>
/// <param name="detectedPlateHandlerGeoCoord"> Callback of the most confident plate with the location and the image itself <see cref="DetectedPlateHandlerGeoCoord"/> </param>
/// <returns><see cref="Task"/></returns>
public async Task DetectAndProcess(LPImageData lpImageData, DetectedPlateHandlerGeoCoord detectedPlateHandlerGeoCoord)
{
await Detect(lpImageData, (OpenAlprData openAlprData, SoftwareBitmap bitmap, int err) =>
{
string final_plate = openAlprData.GetMostConfidentPlate().First;
detectedPlateHandlerGeoCoord(new DetectedLpData(final_plate, lpImageData.lat, lpImageData.lon, bitmap), err);
});
}
/// <summary>
/// Enqueue new LPImageData
/// </summary>
/// <param name="lPImageData"></param>
public void Enqueue(LPImageData lPImageData)
{
lock (_lock)
{
if (GetCount() <= limit)
{
pool.Enqueue(lPImageData);
}
else
{
throw new OutOfMemoryException();
}
}
}
/// <summary>
/// Sends the given storage file with the LPImageData combined to the NodeJS server
/// </summary>
/// <param name="storageFile"> Image file that possibly contains the license plate of a car </param>
/// <param name="pImageData"> This contains the location the image, lat and lon, lpImage is not used </param>
/// <returns>OpenAlprData that contains the detected plate from an image <see cref="OpenAlprData"/></returns>
private OpenAlprData UseOpenAlpr(StorageFile storageFile, LPImageData pImageData)
{
string CT = "file";
string fullPath = storageFile.Path;
FormUpload.FileParameter f = null;
for (int i = 1; i < 10; i++)
{
try
{ /*Try to read from a file until you succeed*/
f = new FormUpload.FileParameter(File.ReadAllBytes(fullPath), storageFile.Name, "multipart/form-data");
break;
}
catch (IOException e)
{
Thread.Sleep(1000 * i);
Debug.WriteLine("File Load Exception OPENALPR " + i + " : " + e.ToString());
}
}
/*Build the post request*/
Dictionary <string, object> d = new Dictionary <string, object>();
d.Add(CT, f);
d.Add("detected_lat", pImageData.lat);
d.Add("detected_lon", pImageData.lon);
string ua = "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.2 (KHTML, like Gecko) Chrome/15.0.874.121 Safari/535.2"; /* I Don't know what this does*/
var wr = FormUpload.MultipartFormDataPost("http://localhost:8081/file_upload_alpr", ua, d);
WebResponse wresp = null;
string result = "";
try
{
Stream stream2 = wr.GetResponseStream();
StreamReader reader2 = new StreamReader(stream2);
result = reader2.ReadToEnd();
Debug.WriteLine(string.Format("File uploaded {0}, server response is: {1}", "http://localhost:8081/file_upload_alpr", result));
}
catch (Exception ex)
{
Debug.WriteLine("Error uploading file", ex);
if (wresp != null)
{
wresp.Close();
wresp = null;
}
}
finally
{
wr = null;
}
/*Build the response as a OpenAlprData*/
JsonObject jsonObject;
OpenAlprData openAlprData = new OpenAlprData();
if (JsonObject.TryParse(result, out jsonObject))
{
openAlprData.Parse(jsonObject);
}
return(openAlprData);
}