ImageEvents_CSharp¶
ImageEvents_CSharp.cs shows how to acquire images using the image event handler. It relies on information provided in the Enumeration_CSharp, Acquisition_CSharp, and NodeMapInfo_CSharp examples.
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/**
* @example ImageEvents_CSharp.cs
*
* @brief ImageEvents_CSharp.cs shows how to acquire images using the image
* event handler. It relies on information provided in the Enumeration_CSharp,
* Acquisition_CSharp, and NodeMapInfo_CSharp examples.
*
* It can also be helpful to familiarize yourself with the
* NodeMapCallback_CSharp example, as nodemap callbacks follow the same
* general procedure as events, but with a few less steps.
*
* This example creates a user-defined class, ImageEventListener, that inherits
* from the Spinnaker class, ManagedImageEventHandler. ImageEventListener allows the
* user to define any properties, parameters, and the event itself while
* ManagedImageEventHandler allows the child class to appropriately interface with
* Spinnaker.
*
* Please leave us feedback at: https://www.surveymonkey.com/r/TDYMVAPI
* More source code examples at: https://github.com/Teledyne-MV/Spinnaker-Examples
* Need help? Check out our forum at: https://teledynevisionsolutions.zendesk.com/hc/en-us/community/topics
*/
using System;
using System.Collections.Generic;
using System.IO;
using System.Threading;
using SpinnakerNET;
using SpinnakerNET.GenApi;
namespace ImageEvents_CSharp
{
class Program
{
// This class defines the properties, parameters, and the event handler itself.
// Take a moment to notice what parts of the class are mandatory, and
// what have been added for demonstration purposes. First, any class
// used to define image event handlers must inherit from ManagedImageEventHandler.
// Second, the method signature of OnImageEvent() must also be
// consistent and follow the override keyword. Everything else,
// including the constructor, properties, body of OnImageEvent(), and
// other functions, is particular to the example.
class ImageEventListener : ManagedImageEventHandler
{
private string deviceSerialNumber;
public const int NumImages = 10;
public int imageCnt;
IManagedImageProcessor processor;
// The constructor retrieves the serial number and initializes the
// image counter to 0.
public ImageEventListener(IManagedCamera cam)
{
// Initialize image counter to 0
imageCnt = 0;
// Retrieve device serial number
INodeMap nodeMap = cam.GetTLDeviceNodeMap();
deviceSerialNumber = "";
IString iDeviceSerialNumber = nodeMap.GetNode<IString>("DeviceSerialNumber");
if (iDeviceSerialNumber != null && iDeviceSerialNumber.IsReadable)
{
deviceSerialNumber = iDeviceSerialNumber.Value;
}
//
// Create ImageProcessor instance for post processing images
//
processor = new ManagedImageProcessor();
//
// Set default image processor color processing method
//
// *** NOTES ***
// By default, if no specific color processing algorithm is set, the image
// processor will default to NEAREST_NEIGHBOR method.
//
processor.SetColorProcessing(ColorProcessingAlgorithm.HQ_LINEAR);
}
// This method defines an image event. In it, the image that
// triggered the event is converted and saved before incrementing
// the count. Please see Acquisition_CSharp example for more
// in-depth comments on the acquisition of images.
override protected void OnImageEvent(ManagedImage image)
{
if (imageCnt < NumImages)
{
Console.WriteLine("Image event occurred...");
if (image.IsIncomplete)
{
Console.WriteLine("Image incomplete with image status {0}...\n", image.ImageStatus);
}
else
{
// Convert image
using(IManagedImage convertedImage = processor.Convert(image, PixelFormatEnums.Mono8))
{
// Print image information
Console.WriteLine(
"Grabbed image {0}, width = {1}, height = {2}",
imageCnt,
convertedImage.Width,
convertedImage.Height);
// Create unique filename in order to save file
String filename = "ImageEvents-CSharp-";
if (deviceSerialNumber != "")
{
filename = filename + deviceSerialNumber + "-";
}
filename = filename + imageCnt + ".jpg";
// Save image
convertedImage.Save(filename);
Console.WriteLine("Image saved at {0}\n", filename);
// Increment image counter
imageCnt++;
}
}
// Must manually release the image to prevent buffers on the camera stream from filling up
image.Release();
}
}
}
// This function configures the example to execute image events by
// preparing and registering an image event.
int ConfigureImageEvents(IManagedCamera cam, ref ImageEventListener imageEventListener)
{
int result = 0;
Console.WriteLine("\n\n*** CONFIGURING IMAGE EVENTS ***\n");
try
{
//
// Create image event
//
// *** NOTES ***
// The class has been constructed to accept a managed camera
// in order to allow the saving of images with the device
// serial number.
//
imageEventListener = new ImageEventListener(cam);
//
// Register image event handler
//
// *** NOTES ***
// Image events are registered to cameras. If there are
// multiple cameras, each camera must have the image events
// registered to it separately. Also, multiple image events may
// be registered to a single camera.
//
// *** LATER ***
// Image events must be unregistered manually. This must be
// done prior to releasing the system and while the image
// events are still in scope.
//
cam.RegisterEventHandler(imageEventListener);
}
catch (SpinnakerException ex)
{
Console.WriteLine("Error: {0}", ex.Message);
result = -1;
}
return result;
}
// This function waits for the appropriate amount of images. Notice
// that whereas most examples actively retrieve images, the acquisition
// of images is handled passively in this example.
int WaitForImages(ref ImageEventListener imageEventListener)
{
int result = 0;
try
{
//
// Wait for images
//
// *** NOTES ***
// In order to passively capture images using image events and
// automatic polling, the main thread sleeps in increments of
// 200 ms until 10 images have been acquired and saved.
//
const int sleepDuration = 200;
while (imageEventListener.imageCnt < ImageEventListener.NumImages)
{
Console.WriteLine("\t//");
Console.WriteLine("\t// Sleeping for {0} time slices. Grabbing images...", sleepDuration);
Console.WriteLine("\t//");
Thread.Sleep(sleepDuration);
}
}
catch (SpinnakerException ex)
{
Console.WriteLine("Error: {0}", ex.Message);
result = -1;
}
return result;
}
// This functions resets the example by unregistering the image event handler.
int ResetImageEvents(IManagedCamera cam, ref ImageEventListener imageEventListener)
{
int result = 0;
try
{
//
// Unregister image event handler
//
// *** NOTES ***
// It is important to unregister all image event handlers from all
// cameras they are registered to.
//
cam.UnregisterEventHandler(imageEventListener);
Console.WriteLine("Image events unregistered...\n");
}
catch (SpinnakerException ex)
{
Console.WriteLine("Error: {0}", ex.Message);
result = -1;
}
return result;
}
// This function prints the device information of the camera from the
// transport layer; please see NodeMapInfo_CSharp example for more
// in-depth comments on printing device information from the nodemap.
static int PrintDeviceInfo(INodeMap nodeMap)
{
int result = 0;
try
{
Console.WriteLine("\n*** DEVICE INFORMATION ***\n");
ICategory category = nodeMap.GetNode<ICategory>("DeviceInformation");
if (category != null && category.IsReadable)
{
for (int i = 0; i < category.Children.Length; i++)
{
Console.WriteLine(
"{0}: {1}",
category.Children[i].Name,
(category.Children[i].IsReadable ? category.Children[i].ToString()
: "Node not available"));
}
Console.WriteLine();
}
else
{
Console.WriteLine("Device control information not available.");
}
}
catch (SpinnakerException ex)
{
Console.WriteLine("Error: {0}", ex.Message);
result = -1;
}
return result;
}
// This function passively waits for images by calling WaitForImages().
// Notice that this function is much shorter than the AcquireImages()
// function of other examples. This is because most of the code has
// been moved to the image event's OnImageEvent() method.
int AcquireImages(
IManagedCamera cam,
INodeMap nodeMap,
INodeMap nodeMapTLDevice,
ref ImageEventListener imageEventListener)
{
int result = 0;
Console.WriteLine("\n*** IMAGE ACQUISITION ***\n");
try
{
// Set acquisition mode to continuous
IEnum iAcquisitionMode = nodeMap.GetNode<IEnum>("AcquisitionMode");
if (iAcquisitionMode == null || !iAcquisitionMode.IsReadable || !iAcquisitionMode.IsWritable)
{
Console.WriteLine("Unable to set acquisition mode to continuous (node retrieval). Aborting...\n");
return -1;
}
IEnumEntry iAcquisitionModeContinuous = iAcquisitionMode.GetEntryByName("Continuous");
if (iAcquisitionModeContinuous == null || !iAcquisitionModeContinuous.IsReadable)
{
Console.WriteLine(
"Unable to get acquisition mode to continuous (enum entry retrieval). Aborting...\n");
return -1;
}
iAcquisitionMode.Value = iAcquisitionModeContinuous.Symbolic;
Console.WriteLine("Acquisition mode set to continuous...");
// Begin acquiring images
cam.BeginAcquisition();
Console.WriteLine("Acquiring images...");
// Retrieve images using image event handler
result = WaitForImages(ref imageEventListener);
// End acquisition
cam.EndAcquisition();
}
catch (SpinnakerException ex)
{
Console.WriteLine("Error: {0}", ex.Message);
result = -1;
}
return result;
}
// This function acts as the body of the example; please see
// NodeMapInfo_CSharp example for more in-depth comments on setting up
// cameras.
int RunSingleCamera(IManagedCamera cam)
{
int result = 0;
int err = 0;
try
{
// Retrieve TL device nodemap and print device information
INodeMap nodeMapTLDevice = cam.GetTLDeviceNodeMap();
result = PrintDeviceInfo(nodeMapTLDevice);
// Initialize camera
cam.Init();
// Retrieve GenICam nodemap
INodeMap nodeMap = cam.GetNodeMap();
// Configure image event handlers
ImageEventListener imageEventListener = null;
err = ConfigureImageEvents(cam, ref imageEventListener);
if (err < 0)
{
return err;
}
// Acquire images using the image event handler
result = result | AcquireImages(cam, nodeMap, nodeMapTLDevice, ref imageEventListener);
// Reset image event handlers
result = result | ResetImageEvents(cam, ref imageEventListener);
// Deinitialize camera
cam.DeInit();
}
catch (SpinnakerException ex)
{
Console.WriteLine("Error: {0}", ex.Message);
result = -1;
}
return result;
}
// Example entry point; please see Enumeration_CSharp example for more
// in-depth comments on preparing and cleaning up the system.
static int Main(string[] args)
{
int result = 0;
Program program = new Program();
// Since this application saves images in the current folder
// we must ensure that we have permission to write to this folder.
// If we do not have permission, fail right away.
FileStream fileStream;
try
{
fileStream = new FileStream(@"test.txt", FileMode.Create);
fileStream.Close();
File.Delete("test.txt");
}
catch
{
Console.WriteLine("Failed to create file in current folder. Please check permissions.");
Console.WriteLine("Press enter to exit...");
Console.ReadLine();
return -1;
}
// Retrieve singleton reference to system object
ManagedSystem system = new ManagedSystem();
// Print out current library version
LibraryVersion spinVersion = system.GetLibraryVersion();
Console.WriteLine(
"Spinnaker library version: {0}.{1}.{2}.{3}\n\n",
spinVersion.major,
spinVersion.minor,
spinVersion.type,
spinVersion.build);
// Retrieve list of cameras from the system
ManagedCameraList camList = system.GetCameras();
Console.WriteLine("Number of cameras detected: {0}\n\n", camList.Count);
// Finish if there are no cameras
if (camList.Count == 0)
{
// Clear camera list before releasing system
camList.Clear();
// Release system
system.Dispose();
Console.WriteLine("Not enough cameras!");
Console.WriteLine("Done! Press Enter to exit...");
Console.ReadLine();
return -1;
}
// Run example on each camera
int index = 0;
foreach(IManagedCamera managedCamera in camList) using(managedCamera)
{
Console.WriteLine("Running example for camera {0}...", index);
try
{
// Run example
result = result | program.RunSingleCamera(managedCamera);
}
catch (SpinnakerException ex)
{
Console.WriteLine("Error: {0}", ex.Message);
result = -1;
}
Console.WriteLine("Camera {0} example complete...\n", index++);
}
// Clear camera list before releasing system
camList.Clear();
// Release system
system.Dispose();
Console.WriteLine("\nDone! Press Enter to exit...");
Console.ReadLine();
return result;
}
}
}