Dear UVC Developers, I am working on developing a UVC camera. The camera itself runs linux kernel and uses the gadget mode. We have a gadget driver written and an application running on the device, which pushes data over USB to the host when host requests data. The camera works in Isochronous mode and copies 1024 bytes every microframe.
With a bit of effort (which mostly involved correcting some of the descriptor values on the device side), I could get uvcvideo driver on the host to work with the camera. luvcview works fine, so is a simpe gstreamer viewer which uses the v4l2src element. We would like to get the camera working well with the uvcvideo and is completely standards compliant. Below are some of the issues observed, I would appreciate any tips to debug the issue. The kernel message on the host says that the the uvcvideo invokes quirks=1. kernel: [88819.299222] uvcvideo: Forcing device quirks 0x1 by module parameter for testing purpose. kernel: [88819.299227] uvcvideo: Please report required quirks to the linux-uvc-devel mailing list. I am wondering why quirks was turned on to a value of 1 and see what can be done at the device side to fix it. I am using gstreamer to stream from the camera and display the frames. with the pipeline arranged as follows. gst-launch v4l2src ! jpegdec ! ffmpegcolorspace ! xvimagesink I see that the gstreamer quits after streaming for afew hours saying that there is an error in the JPEG stream. It looks like some corruption is happening to the JPEG frames inside the camera. But I see no USB messages on the host or the device. To narrow down the problem, we have an application which takes one JPEG image and keep streaming them continuously, instead of using the ones from the camera. This probably will validate the USB data path. It will be great if uvc developers can throw some light on how to debug these issues. regards John
_______________________________________________ Linux-uvc-devel mailing list [email protected] https://lists.berlios.de/mailman/listinfo/linux-uvc-devel
