fixing cap_pvpapi interface and making sure both AVT Manta and Proscilla

series are supported. Testing this with both cams for Windows and Linux
exhaustively.

Optimizing memory footprint by removing unused calls.

Adapted with the input of Shai

Added small example that illustrates how it should work.

modules/highgui/src/cap_pvapi.cpp

@@ -139,124 +139,125 @@ void CvCaptureCAM_PvAPI::close()
 }
 
 // Initialize camera input
-bool CvCaptureCAM_PvAPI::open( int index )
+bool CvCaptureCAM_PvAPI::open( int )
 {
     tPvCameraInfo cameraList[MAX_CAMERAS];
-
     tPvCameraInfo  camInfo;
     tPvIpSettings ipSettings;
 
+    // Initialization parameters [500 x 10 ms = 5000 ms timeout]
+    int initializeTimeOut = 500;
 
-    if (PvInitialize()) {
-    }
-    //return false;
+    // Disregard any errors, since this might be called several times and only needs to be called once or it will return an
+    // Important when wanting to use more than 1 AVT camera at the same time
+    PvInitialize();
 
-    Sleep(1000);
+    while((!PvCameraCount())  && (initializeTimeOut--))
+        Sleep(10);
 
-    //close();
+    if (!initializeTimeOut){
+        fprintf(stderr,"ERROR: camera intialisation timeout [5000ms].\n");
+        return false;
+    }
 
-    int numCameras=PvCameraList(cameraList, MAX_CAMERAS, NULL);
+    unsigned int numCameras = PvCameraList(cameraList, MAX_CAMERAS, NULL);
 
-    if (numCameras <= 0 || index >= numCameras)
+    // If no cameras are found
+    if(!numCameras)
+    {
+        fprintf(stderr, "ERROR: No cameras found.\n");
         return false;
+    }
 
-    Camera.UID = cameraList[index].UniqueId;
-
-    if (!PvCameraInfo(Camera.UID,&camInfo) && !PvCameraIpSettingsGet(Camera.UID,&ipSettings)) {
-        /*
-        struct in_addr addr;
-        addr.s_addr = ipSettings.CurrentIpAddress;
-        printf("Current address:\t%s\n",inet_ntoa(addr));
-        addr.s_addr = ipSettings.CurrentIpSubnet;
-        printf("Current subnet:\t\t%s\n",inet_ntoa(addr));
-        addr.s_addr = ipSettings.CurrentIpGateway;
-        printf("Current gateway:\t%s\n",inet_ntoa(addr));
-        */
+    // Try opening the cameras in the list, one-by-one until a camera that is not used is found
+    unsigned int findNewCamera;
+    for(findNewCamera=0; findNewCamera<numCameras; findNewCamera++)
+    {
+        Camera.UID = cameraList[findNewCamera].UniqueId;
+        if(PvCameraOpen(Camera.UID, ePvAccessMaster, &(Camera.Handle))==ePvErrSuccess)
+            break;
     }
-    else {
-        fprintf(stderr,"ERROR: could not retrieve camera IP settings.\n");
+
+    if(findNewCamera == numCameras)
+    {
+        fprintf(stderr, "Could not find a new camera to connect to.\n");
         return false;
     }
 
-
-    if (PvCameraOpen(Camera.UID, ePvAccessMaster, &(Camera.Handle))==ePvErrSuccess)
+    if(PvCameraIpSettingsGet(Camera.UID,&ipSettings)==ePvErrNotFound)
     {
+        fprintf(stderr, "The specified camera UID %lu could not be found, PvCameraIpSettingsGet().\n", Camera.UID);
+        return false;
+    }
 
-        //Set Pixel Format to BRG24 to follow conventions
-        /*Errcode = PvAttrEnumSet(Camera.Handle, "PixelFormat", "Bgr24");
-        if (Errcode != ePvErrSuccess)
+    if(PvCameraInfo(Camera.UID,&camInfo)==ePvErrNotFound)
     {
-            fprintf(stderr, "PvAPI: couldn't set PixelFormat to Bgr24\n");
-            return NULL;
+        fprintf(stderr, "The specified camera UID %lu could not be found, PvCameraInfo().\n", Camera.UID);
+        return false;
     }
-        */
+
     tPvUint32 frameWidth, frameHeight, frameSize;
-        unsigned long maxSize;
     char pixelFormat[256];
     PvAttrUint32Get(Camera.Handle, "TotalBytesPerFrame", &frameSize);
     PvAttrUint32Get(Camera.Handle, "Width", &frameWidth);
     PvAttrUint32Get(Camera.Handle, "Height", &frameHeight);
     PvAttrEnumGet(Camera.Handle, "PixelFormat", pixelFormat,256,NULL);
-        maxSize = 8228;
-        //PvAttrUint32Get(Camera.Handle,"PacketSize",&maxSize);
-        if (PvCaptureAdjustPacketSize(Camera.Handle,maxSize)!=ePvErrSuccess)
+
+    // Start the camera
+    PvCaptureStart(Camera.Handle);
+
+    // Set the camera explicitly to capture data frames continuously
+    if(PvAttrEnumSet(Camera.Handle, "AcquisitionMode", "Continuous")!= ePvErrSuccess)
+    {
+        fprintf(stderr,"Could not set Acquisition Mode\n");
         return false;
+    }
+
+    if(PvCommandRun(Camera.Handle, "AcquisitionStart")!= ePvErrSuccess)
+    {
+        fprintf(stderr,"Could not start acquisition\n");
+        return false;
+    }
+
+    if(PvAttrEnumSet(Camera.Handle, "FrameStartTriggerMode", "Freerun")!= ePvErrSuccess)
+    {
+        fprintf(stderr,"Error setting trigger to \"Freerun\"");
+        return false;
+    }
+
+    // Settings depending on the pixelformat
+    // This works for all AVT camera models that use the PvAPI interface
     if (strcmp(pixelFormat, "Mono8")==0) {
+        monocrome = true;
         grayframe = cvCreateImage(cvSize((int)frameWidth, (int)frameHeight), IPL_DEPTH_8U, 1);
         grayframe->widthStep = (int)frameWidth;
-                frame = cvCreateImage(cvSize((int)frameWidth, (int)frameHeight), IPL_DEPTH_8U, 3);
-                frame->widthStep = (int)frameWidth*3;
         Camera.Frame.ImageBufferSize = frameSize;
         Camera.Frame.ImageBuffer = grayframe->imageData;
     }
     else if (strcmp(pixelFormat, "Mono16")==0) {
+        monocrome = true;
         grayframe = cvCreateImage(cvSize((int)frameWidth, (int)frameHeight), IPL_DEPTH_16U, 1);
-                grayframe->widthStep = (int)frameWidth;
-                frame = cvCreateImage(cvSize((int)frameWidth, (int)frameHeight), IPL_DEPTH_16U, 3);
-                frame->widthStep = (int)frameWidth*3;
+        grayframe->widthStep = (int)frameWidth*2;
         Camera.Frame.ImageBufferSize = frameSize;
         Camera.Frame.ImageBuffer = grayframe->imageData;
     }
     else if (strcmp(pixelFormat, "Bgr24")==0) {
+        monocrome = false;
         frame = cvCreateImage(cvSize((int)frameWidth, (int)frameHeight), IPL_DEPTH_8U, 3);
         frame->widthStep = (int)frameWidth*3;
         Camera.Frame.ImageBufferSize = frameSize;
         Camera.Frame.ImageBuffer = frame->imageData;
     }
-        else
-                return false;
-        // Start the camera
-        PvCaptureStart(Camera.Handle);
-
-        // Set the camera to capture continuously
-        if(PvAttrEnumSet(Camera.Handle, "AcquisitionMode", "Continuous")!= ePvErrSuccess)
-        {
-            fprintf(stderr,"Could not set Prosilica Acquisition Mode\n");
-            return false;
-        }
-
-        if(PvCommandRun(Camera.Handle, "AcquisitionStart")!= ePvErrSuccess)
-        {
-            fprintf(stderr,"Could not start Prosilica acquisition\n");
-            return false;
-        }
-
-        if(PvAttrEnumSet(Camera.Handle, "FrameStartTriggerMode", "Freerun")!= ePvErrSuccess)
-        {
-            fprintf(stderr,"Error setting Prosilica trigger to \"Freerun\"");
+    else{
+        fprintf(stderr, "Pixel format %s not supported; only Mono8, Mono16 and Bgr24 are currently supported.\n", pixelFormat);
         return false;
     }
 
     return true;
-    }
-    fprintf(stderr,"Error cannot open camera\n");
-    return false;
-
 }
 
 bool CvCaptureCAM_PvAPI::grabFrame()
 {
-    //if(Camera.Frame.Status != ePvErrUnplugged && Camera.Frame.Status != ePvErrCancelled)
     return PvCaptureQueueFrame(Camera.Handle, &(Camera.Frame), NULL) == ePvErrSuccess;
 }
 
@@ -266,7 +267,6 @@ IplImage* CvCaptureCAM_PvAPI::retrieveFrame(int)
 
     if (PvCaptureWaitForFrameDone(Camera.Handle, &(Camera.Frame), 1000) == ePvErrSuccess) {
         if (!monocrome) {
-            cvMerge(grayframe,grayframe,grayframe,NULL,frame);
             return frame;
         }
         return grayframe;

samples/cpp/videocapture_pvapi.cpp

+//////////////////////////////////////////////////////
+// Sample illustrating the use of the VideoCapture  //
+// interface in combination with PvAPI interface    //
+//                                                  //
+// Succesfully tested on Prosilica and Manta series //
+//////////////////////////////////////////////////////
+
+#include <iostream>
+#include "opencv2/opencv.hpp"
+
+using namespace std;
+using namespace cv;
+
+int main()
+{
+    // Capturing multiple AVT cameras can be done by simply initiating
+    // two VideoCaptures after eachother.
+    VideoCapture camera1(0 + CV_CAP_PVAPI);
+    VideoCapture camera2(0 + CV_CAP_PVAPI);
+    Mat frame1, frame2;
+
+    for(;;){
+        camera1 >> frame1;
+        camera2 >> frame2;
+
+        imshow("camera 1 frame", frame1);
+        imshow("camera 2 frame", frame2);
+
+        int key = waitKey(10);
+        if(key == 27){
+            break;
+        }
+    }
+
+    return 0;
+}