971245 - Webcam access does not work, often crashes Firefox

Status: RESOLVED WORKSFORME

(Core :: WebRTC: Audio/Video, defect)

Description

[Ralf Jung]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:27.0) Gecko/20100101 Firefox/27.0 (Beta/Release)
Build ID: 20140127194636

Steps to reproduce:

I tried to use any website which accesses the webcam, like for example https://palava.tv/ or https://apprtc.appspot.com/ or http://mozilla.github.io/webrtc-landing/gum_test.html .


Actual results:

In some cases, seemingly nothing happens (no question concerning webcam access, and no webcam picture on the size). Firefox starts fully utilizing one of my CPU cores. Quitting does not help, I need to SIGINT the process to get rid of it.
Alternatively, Firefox just crashes. I reported one of these crashes with the crash report tool, please let me know if there's any ID in the email that may help you to identify the report.
Both of these happen randomly, the first is slightly more likely than the second.

Further information:
I am running the 64bit Firefox 27 from Mozilla on Debian Testing amd64.
The webcam preview in "v4l2ucp" works fine, and so does the following command: "gst-launch-0.10 v4l2src device=/dev/video0 ! 'video/x-raw-yuv,width=640,height=480,framerate=30/1' ! xvimagesink". The first two of the aforementioned websites work fine on this machine in Chromium 31. Hence I am pretty sure the webcam is all right, v4l2 can access it, and so can gstreamer.
Unfortunately I could not figure out which library Firefox uses to access webcams, so I have no idea how to continue debugging. There's no output on the in-browser console or stdout/stderr (except for a GLib assert that's always shown on startup).


Expected results:

Firefox should ask me for Webcam access, and then the sites should work fine.

Comment 1

[Randell Jesup [:jesup] (needinfo me)]

Can you try a Debug build (http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/), and set up logs for NSPR_LOG_MODULES=getusermedia:5,mediamanager:5,webrtc_trace:65535 and WEBRTC_TRACE_FILE=whatever NSPR_LOG_FILE=another_file (see https://wiki.mozilla.org/Media/WebRTC/Logging) and upload both to this bug.

Also, the exact version and maker of the webcam (and any firmware versions known).

Thanks

Comment 2

[Ralf Jung]

Yes, I can do that - however, that folder contains >100 subfolders. Which one do I have to use?

The webcam is built into my Asus X53SM. lsusb says

  Bus 001 Device 004: ID 13d3:5710 IMC Networks UVC VGA Webcam

I couldn't (yet) figure out more details.

Comment 3

[Ralf Jung]

dmesg says concerning the webcam:

[    2.284993] usb 1-1.2: New USB device found, idVendor=13d3, idProduct=5710
[    2.285013] usb 1-1.2: New USB device strings: Mfr=3, Product=1, SerialNumber=2
[    2.285019] usb 1-1.2: Product: USB 2.0 UVC VGA WebCam
[    2.285023] usb 1-1.2: Manufacturer: Azurewave
[    2.285028] usb 1-1.2: SerialNumber: 0x0001

[    7.734021] uvcvideo: Found UVC 1.00 device USB 2.0 UVC VGA WebCam (13d3:5710)

[    7.740369] input: USB 2.0 UVC VGA WebCam as /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.2/1-1.2:1.0/input/input19
[    7.740427] usbcore: registered new interface driver uvcvideo
[    7.740430] USB Video Class driver (1.1.1)

Comment 4

[Ralf Jung]

So I decided to just give some version a try and downloaded this one:
<https://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/2014/02/2014-02-23-mozilla-beta-debug/>
Interesting enough, the microphone and webcam worked just fine there: On palava.tv, I was asked for mic and webcam access, and the webcam image appeared. On <https://www.webrtc-experiment.com/RecordRTC/>, both recording an audio sample and recording the webcam to an animated GIF worked (the site seems to be a bit buggy though, I had to reload it between the two recordings).

So I also tried the debug version of the current stable branch <https://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/2014/02/2014-02-23-mozilla-release-debug/>, and again, the webcam worked. The microphone however did not, or at least, the questions for microphone access did not appear on palava.tv (it just asked for webcam access, even though I clicked "Video & Audio"). On the RecordRTC site, recording the webcam to a GIF worked, but recording the audio did not.

I tried <https://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/2014/02/2014-02-23-00-40-01-mozilla-aurora/> which I think is a release build (at least it doesn't say "debug" anywhere), and again everything worked.

Finally, I re-downloaded <https://ftp.mozilla.org/pub/mozilla.org/firefox/releases/27.0.1/linux-x86_64/en-US/> and everything was broken as described previously in this bug.

I captured logfiles of doing the following in the 27.0.1 nightly debug build:
* Go to palava.tv, start a "Private" "Audio & Video" conference. It asks for webcam access only (which is wrong). Check the video works.
* Open a new tab, close palava.tv
* Go to https://www.webrtc-experiment.com/RecordRTC, record a short webcam snippet to animated GIF, view the GIF to check it worked
* Reload (by going to URL bar and hitting enter)
* Try to record an audio snippet - it doesn't work
* Close Firefox
However, when I quit firefox, nspr-log gets totally garbled - it first contains a few KB worth of 0x00, and then two shutdown lines. So I copied the logfiles *before* I quit firefox.

Comment 5

[Ralf Jung]

Attachment: WebRTC trace of my tests in Firefox 27.0.1 Nightly

Comment 6

[Ralf Jung]

Attachment: NSPR log of my tests in Firefox 27.0.1 Nightly

Comment 7

[Ralf Jung]

The bug seems to be fixed in Firefox 28 :) At least, all the above pages now work as expected.

Unfortunately, I cannot resolve the bug as FIXED, so I'd appreciate if someone else could do that.

Comment 8

[Randell Jesup [:jesup] (needinfo me)]

28 has an updated set of code from webrtc.org, that may have fixed it.