VideoCapture not obtaining newest frames when I run read()

asked 2015-12-28 10:33:15 -0600

Hey guys, I'm using a VideoCapture from a C920 to read() the latest/newest images from the camera. I've noticed that unless I'm constantly looping the VideoCapture.read(), that I don't get the newest images but something in a buffer since the picture is clearly "older" than what the current frame should be.

I'm using this with ROS/mavros to command a multicopter to move, if that relates to anything. I might be able to get some code here if what I said doesn't make sense. Has anyone heard of this happening? Is there another way to grab the newest image from the camera?

Thanks!

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answered 2016-01-03 20:02:04 -0600

harsha
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updated 2016-01-03 20:17:10 -0600

If you're using ROS, it might be better to use usb_cam package to open a usb camera. You can subscribe to the image topic, use cv_bridge to convert sensor_msgs::image to cv::Mat, process your image and publish or send service calls from there. This way you'll always get the latest frame for your callback.

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So, there's not anything "wrong" happening with the video capture? Or is this just a way to circumvent the issue? I'll try this, but I'm using Python instead of C++.