Video Stream drops when goes over 720p (but only on H264)

[Andy]

Logitech c930e, latest git compiled ffmpeg & guvcview.

Can use up to 1080p (30fps) on both mjpeg & yuyv no problems but can only get up to 720p with h264. If you push it higher you get the error :

libv4l2: error turning on stream: Input/output error
V4L2_CORE: (VIDIOC_STREAMON) Unable to start capture: Input/output error
V4L2_CORE: (get_v4l2_frame) video stream must be started first
with the last line repeated

if you switch back to 720p or lower the image comes back.

Thanks

[Paulo Assis]

Hi,
I've just tested this and for me every available resolution worked just fine.
In any case VIDIOC_STREAMON is failing for you, this is an error
returned by the driver, so something is failing on the hardware side.
Could it be bandwidth related?
You should check the uvcvideo driver output in you system log (try to
increase the driver verbosity first).

Regards,
Paulo

2015-04-18 14:40 GMT+01:00 Andy liviy@users.sf.net:

Logitech c930e, latest git compiled ffmpeg & guvcview.

Can use up to 1080p (30fps) on both mjpeg & yuyv no problems but can only
get up to 720p with h264. If you push it higher you get the error :

libv4l2: error turning on stream: Input/output error
V4L2_CORE: (VIDIOC_STREAMON) Unable to start capture: Input/output error
V4L2_CORE: (get_v4l2_frame) video stream must be started first
with the last line repeated

if you switch back to 720p or lower the image comes back.

Thanks

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Video Stream drops when goes over 720p (but only on H264)

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[Andy]

uvc module info :
modinfo uvcvideo | head
filename: /lib/modules/3.19.4-200.fc21.x86_64/kernel/drivers/media/usb/uvc/uvcvideo.ko.xz
version: 1.1.1

Driver info :
Driver info:
Driver name : uvcvideo
Card type : Logitech Webcam C930e
Bus info : usb-0000:00:13.2-3
Driver version: 3.19.4
Capabilities : 0x84200001
Video Capture
Streaming
Extended Pix Format
Device Capabilities

I've attached more information about the system (the ubuntu 15.04 system although a FC21 is having exactly the same issue).

Also, a dump from dmesg with uvcvideo tracing turned up. Starts with 720p h264 then i try and go up a resolution, then back to 720p before closing.

If it wasn't quite what you were asking for please can you guide me to get it, I'm used to compiling code and such but not debugging drivers.

Thanks for your help.

Cheers.

[Damiano]

Hello,

I have the same issue on an Ubuntu 14.04 (3.13.0-55-generic kernel): can't go over 720p in H.264 mode.
Is there a fix available?

Thanks a lot.