Hi all, I am using a PXA270 board running linux 2.6.37 equipped with an ov9655 Image sensor. I am able to use the cropping and scaling capabilities V4L2 driver. The question is : Is it possible dynamically change the cropping and scaling values without close and re-open the camera every time ? Now I am using the streaming I/O memory mapping and to dynamically change the cropping and scaling values I do : 1) stop capturing using VIDIOC_STREAMOFF; 2) unmap all the buffers; 3) close the device; 4) open the device; 5) init the device: VIDIOC_CROPCAP and VIDIOC_S_CROP in order to set the cropping parameters. VIDIOC_G_FMT and VIDIOC_S_FMT in order to set the target image width and height, (scaling). 6) Mapping the buffers: VIDIOC_REQBUFS in order to request buffers and mmap each buffer using VIDIOC_QUERYBUF and mmap(): this procedure works but take 400 ms. If I omit steps 3) and 4) (close and re-open the device) I get this errors: camera 0-0: S_CROP denied: queue initialised and sizes differ camera 0-0: S_FMT denied: queue initialised VIDIOC_S_FMT error 16, Device or resource busy pxa27x-camera pxa27x-camera.0: PXA Camera driver detached from camera 0 Do you have some Idea regarding why I have to close and reopen the device and regarding a way to speed up these change? Thanks in advance Paolo Santinelli -- -------------------------------------------------- Paolo Santinelli ImageLab Computer Vision and Pattern Recognition Lab Dipartimento di Ingegneria dell'Informazione Universita' di Modena e Reggio Emilia via Vignolese 905/B, 41125, Modena, Italy Cell. +39 3472953357, Office +39 059 2056270, Fax +39 059 2056129 email: <mailto:paolo.santinelli@xxxxxxxxxx> paolo.santinelli@xxxxxxxxxx URL: <http://imagelab.ing.unimo.it/> http://imagelab.ing.unimo.it -------------------------------------------------- -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
