uvc_find_device 返回-4， uvc_get_device_with_fd 返回 0

saki4510t / UVCCamera

library and sample to access to UVC web camera on non-rooted Android device

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Open ChineseBoyLY opened 5 years ago

ChineseBoyLY commented 5 years ago

uvc_find_device(ctx, &dev, 0, 0, NULL); 返回-4

而用uvc_get_device_with_fd(ctx, &dev, vid, pid, NULL, fd, busnum, devaddr); 就没有问题

请问这是为何？

mingtong commented 5 years ago

请使用英文. Please use English to describe your issue, then more people can help you.

jumpy88 commented 3 years ago

Hi @ChineseBoyLY @mingtong , I'm trying to call uvc_get_device_with_fd but I can't find any documentation explaining how to use it. How should I get fd? I think the need to use uvc_get_device_with_fd is related to root privileges. Look at this comment in source code https://github.com/saki4510t/UVCCamera/blob/c9399e63dfab4b6d260d8cbef92182abc6de0ee0/libuvccamera/src/main/jni/libuvc/src/device.c#L206