Blackscreen on OpenMV with Image Transfer

Hi all
I’m currently working with the OpenMV cam and wanted to transfer Images using the example code. Sadly I only get a Blackscreen and 0 fps. Printing the img variable also outputs ‘None’. I used the example code ‘rpc_image_transfer_jpg_as_the_controller_device.py’ in a set up project with rpc.py and the corresponding main.py for the openmv cam. I know that this has been discussed on the forum many times before but I couldn’t find a solution, so I just wanted to ask if it has been solved yet.
PS: Note that this is just to get into using the OpenMV cam, for my actual project I just want to send a vector to the PC, so if there is a way to do that without the problems that image transfer has, let me know :wink:

Hi, this is easier:

openmv/openmv: OpenMV Camera Module (github.com)

Getting the RPC image transfer setup is not technically that hard. However, there are some stumbling blocks with it that can result in issues. In general, I do not recommend using the product to send images to the PC as this is not the point of the OpenMV Cam. It’s designed to process images onboard and transmit results somewhere or directly control things.

Thanks for the quick answer. I’m currently not on my PC to try it out but just a quick question: the print() command the doc is referring to is just the normal python print() ?

Yes, print just goes out and can be read by any program.

How can I start the main.py file from the camera using my computer python file? Simply using the Openmv IDE seems to be blocking acces to the camera port when I try to read the print() outputs with my computer py file

Yeah, so, first develop your application with OpenMV IDE. You can see the print output in the IDE.

Then, when you are done do Tools->Save Script to OpenMV Cam, and then reset the camera module/unplug from PC. Then plug back in, and use the program you created to open the camera’s serial port. The print data will then be sent to you from the camera.

Yes, but how can I activate the program? Since just running it with a computer application other than openmv ide just runs the program on the Pc, right?

When it’s saved as main.py it starts when the camera boots.

How do I trigger the boot?

The camera boots automatically.