For Those Having Trouble Getting a USB Camera Feed into RoboRealm

Here at team 2172 we have had a great deal of trouble getting a USB camera to feed into RoboRealm through the rio. After 4 days of working (and late nights of research) I determined that our problem was that the AutomaticCapture() function, although it was feeding frames to the smart dash, was not feeding frames to RoboRealm. To solve this problem I copied the code from the Intermediate Vision example program (removing line 39). This code sends a frameevery time the teleop loop loops. It does this by calling the SetImage() function.

To conclude, if you are having trouble with a usb camera outputting to the smart dash be sure that you are using Camera Server code which sets the image using SetImage().

I don’t have access to those examples. Could you post that file?

This is the code directly copied:

#include “WPILib.h”


  • Uses IMAQdx to manually acquire a new image each frame, and annotate the image by drawing
  • a circle on it, and show it on the FRC Dashboard.
    class IntermediateVisionRobot : public SampleRobot
    IMAQdxSession session;
    Image *frame;
    IMAQdxError imaqError;

void RobotInit() override {
// create an image
frame = imaqCreateImage(IMAQ_IMAGE_RGB, 0);
//the camera name (ex “cam0”) can be found through the roborio web interface
imaqError = IMAQdxOpenCamera(“cam0”, IMAQdxCameraControlModeController, &session);
if(imaqError != IMAQdxErrorSuccess) {
DriverStation::ReportError("IMAQdxOpenCamera error: " + std::to_string((long)imaqError) + "
imaqError = IMAQdxConfigureGrab(session);
if(imaqError != IMAQdxErrorSuccess) {
DriverStation::ReportError("IMAQdxConfigureGrab error: " + std::to_string((long)imaqError) + "

void OperatorControl() override {
    // acquire images

    // grab an image, draw the circle, and provide it for the camera server which will
    // in turn send it to the dashboard.
	while(IsOperatorControl() && IsEnabled()) {
		IMAQdxGrab(session, frame, true, NULL);
		if(imaqError != IMAQdxErrorSuccess) {
			DriverStation::ReportError("IMAQdxGrab error: " + std::to_string((long)imaqError) + "

} else {
Wait(0.005); // wait for a motor update time
// stop image acquisition