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Headless jevois : frame to Serial

+2 votes


I am confused as i try to make my A33 JeVois camera to base64 encode a single frame then send this base64 string to nodeMCU thru serial.

I made this python module :

import libjevois as jevois
import cv2
import base64

class img2serial2web:
    def __init__(self):
        self.frame = 0
        self.image_requested = True

    def processNoUSB(self, inframe):
        img = inframe.getCvBGR()

        if self.image_requested:
            retval, cnt = cv2.imencode('.jpg',img)
            bcnt = base64.b64encode(cnt)
            self.image_requested = False

If i try this code with jevois-daemon (replacing processNoUSB(self, inframe) by process(self, inframe, outframe)) the module works great and print the base64 in my terminal. 

But when i import it to th camera and run it using serial commands i have no output at all, except the default jevois log (INF Engine::setFormatInternal: Module [img2serial] loaded, initialized, and ready). 

I really don't know what am i doig wrong.

My goal is to make my nodemcu get a single frame from jevois as a base64 encoded string and then send this string to a php webpage. Any suggestion ?

asked Apr 10, 2020 in Programmer Questions by opusr (520 points)

1 Answer

+1 vote
In no-USB on, you also need to issue a "streamon" command once your module is configured and ready to start work. Before that, it is just waiting idle. Please see


for example.
answered Jun 24, 2020 by JeVois (46,580 points)