OV7725 support sensor.IOCTL_SET_READOUT_WINDOW

Hello, everyone! Should ov7725 sensor now can be support the function IOCTL_SET_READOUT_WINDOW ?

No the OV7725 doesn’t support any ioctl’s.

Does the MT9M114 sensor support this function ?

I tried it but here is what I got :


Yes it should be supported. Can you post the script that you ran ?

Hi, it does in limited cases. Depending on the window size this will cause all kinds of issues. Unlike other cameras you cannot move the window around as freely as you want.

Here is my code :

import sensor, image, time

sensor.reset()                      # Reset and initialize the sensor.
sensor.set_pixformat(sensor.RGB565) # Set pixel format to RGB565 (or GRAYSCALE)
sensor.set_framesize(sensor.QQVGA)   # Set frame size to QVGA (320x240)
sensor.ioctl(sensor.IOCTL_SET_READOUT_WINDOW, (0,0,160,120))

sensor.skip_frames(time = 2000)
clock = time.clock()

    clock.tick()                    # Update the FPS clock.
    img = sensor.snapshot()         # Take a picture and return the image.
    print(clock.fps())              # Note: OpenMV Cam runs about half as fast when connected
                                    # to the IDE. The FPS should increase once disconnected.

Yes, to be clear. I implemented the code but the method flat out doesn’t actually work. The MT9M114 won’t let you change around the readout window as you please.

Thanks for your answer. As I can’t use IOCTL to improve the fps, is there another way to go over the limit of 80 fps ?

There’s a way to go above that. The frame rate for the camera is controlled by a frame rate control register. However, there’s quite a few registers that you have to modify to change the FPS. But, it’s not really that hard.

Are you comfortable reading the register programming manual? I can share that.

Thanks for your answer and your time. I have never done that but I will try.