GUVCViewer comparison is not really useful here because they just save the mjpeg stream coming from the webcam while we reencode it to theora.

> No, I mistook. Indeed when I press "Start recording", one image (from the
> webcam) appear (it is yellowish). Then that is when I press "Stop recording"
> that the window becomes black and Cheese freezes.

Could you elaborate more on this "freeze" thing? Do you press "Stop recording" and it stays unsensitive? the whole interface stops updating itself (e.g. if you move a window over cheese and then move it away does it leave a gray trail?)?

Are the error messages in the terminal still there (i.e. are you using an updated and fixed gspca driver?)? could you attach an updated log here?

What cheese version are you using by the way?

Cheese 2.31.90 on Ubuntu 10.04

I made a screencast to show exactly the problems : https://docs.google.com/leaf?id=0BxYZ-qSXxe3UNzk1NjkyMTItYmM1OC00NmY5LTkwMTYtZDcwYmZjNDc3Y2U5&sort=name&layout=list&num=50
- Cheese display remain black during the first 8s of the video recording.  Recorded video 
- "Stop recording" button only appears at the 3rd second of the video recording.  
- when I press "Stop recording", the following error message appears in the terminal :
(cheese:8380): GLib-GObject-CRITICAL **: g_signal_emit_valist: assertion `signal_id > 0' failed
- after having pressed the "Stop recording" button, it remains grey and inactive. (but I can start other picture or video recordings via the menus)

On the OGG file generated by Cheese ( https://docs.google.com/leaf?id=0BxYZ-qSXxe3UODFmOWQ0ZmItNDQ5Yi00MjVhLTg1YzMtYTgzN2Q2ZmMyNTZj&sort=name&layout=list&num=50 ) :
- the 3 first seconds are missing (like if the record started 3s after I the pressed "Start recording" button)
- the image is freezed at the beginning (sound is ok) : normal video appears 8s after I pressed "Start recording" button.


Hope this helps.

(In reply to comment #2)
> Cheese 2.31.90 on Ubuntu 10.04
> 
> I made a screencast to show exactly the problems :
> https://docs.google.com/leaf?id=0BxYZ-qSXxe3UNzk1NjkyMTItYmM1OC00NmY5LTkwMTYtZDcwYmZjNDc3Y2U5&sort=name&layout=list&num=50

It says "Sorry, the page (or document) you have requested is not available."

> - Cheese display remain black during the first 8s of the video recording. 
> Recorded video 
> - "Stop recording" button only appears at the 3rd second of the video
> recording.  

This looks like bug 564957, are you using a netbook or an old cpu?

> - when I press "Stop recording", the following error message appears in the
> terminal :
> (cheese:8380): GLib-GObject-CRITICAL **: g_signal_emit_valist: assertion
> `signal_id > 0' failed
> - after having pressed the "Stop recording" button, it remains grey and
> inactive. (but I can start other picture or video recordings via the menus)

This is bug 620637, there is a SRU going on in ubuntu for it and you should be able to fix it installing cheese from lucid-proposed or just waiting for it to get in the updates repository.
 
> On the OGG file generated by Cheese (
> https://docs.google.com/leaf?id=0BxYZ-qSXxe3UODFmOWQ0ZmItNDQ5Yi00MjVhLTg1YzMtYTgzN2Q2ZmMyNTZj&sort=name&layout=list&num=50
> ) :
> - the 3 first seconds are missing (like if the record started 3s after I the
> pressed "Start recording" button)
> - the image is freezed at the beginning (sound is ok) : normal video appears 8s
> after I pressed "Start recording" button.

These really are the typical symptoms of a too slow cpu to do live video recording.

As confirmed with Filipo, i uploaded again and these links should be ok:
https://docs.google.com/leaf?id=0BxYZ-qSXxe3UODFmOWQ0ZmItNDQ5Yi00MjVhLTg1YzMtYTgzN2Q2ZmMyNTZj&sort=name&layout=list&num=50
https://docs.google.com/leaf?id=0BxYZ-qSXxe3UNzk1NjkyMTItYmM1OC00NmY5LTkwMTYtZDcwYmZjNDc3Y2U5&sort=name&layout=list&num=50

> As far as I can tell video is working fine. It's just that your webcam
> is particularly slow to start up. Almost all webcams have some seconds
> usually 1 or 2 at the beginning where they output broken/dark frames,
> we never found a way to avoid that, and I don't really know where the
> issue comes from, I guess it's an hardware one. Those jpeg errors may
> be related (or not).

As you can see on the video, there are 2 steps inside the error:
(1) first : as long as the "Stop recording" button does not appear (~3s), the screen in Cheese is black but the video is not created yet.
(2) then : from the moment when "Stop recording" button has appeared, and during ~5S, the screen in Cheese remains black but the video is actually recorded (with a fix image).

I checked with a live-CD of Ubuntu10.10beta (contains 2.31.90), the recorded videos are frozen (so step number 2) during the first 3 or 4 seconds. So as you say it must be due to slow cpu. And it can vary. That is why I propose the following :

What about adding an option in Preferences to add a "Please wait" message above the black screen during a number of seconds that the user could choose ? (e.g. in my case I would set it at 8s, and i would cut the first 5s of my video with another software). This would be a useful indicator.


> What doesn't work is "Stop video recording" button, but that's a known
> issue and fixed in lucid-proposed (if you're using lucid) and in
> 2.31.91 if you're using maverick (not sure if that already entered the
> repositories).
>
> Hope this helps
>
> Filippo

I checked in Lucid's Proposed rep but it contains Cheese 2.30.1 whereas I already have 2.31.90 (so it should have been fixed?). Maverick has 2.31.90.

I will try to install Cheese from GIT on Lucid.

I can download Cheese form the GIT, but can't install it (nor ./configure, nor make, nor sudo checkinstall, nor autogen.sh have effect...), any clue ?


Also, I am wondering why Cheese could not just save the mjpeg stream like GUVCViewer does ? 
(even optionally via Preferences..)

(In reply to comment #4)
> What about adding an option in Preferences to add a "Please wait" message above
> the black screen during a number of seconds that the user could choose ? (e.g.
> in my case I would set it at 8s, and i would cut the first 5s of my video with
> another software). This would be a useful indicator.

This would probably be fixed in the 3.0 version, it will hopefully have throbbers (the spinning thing you see at cheese startup) every time there is a time consuming operation.

> I checked in Lucid's Proposed rep but it contains Cheese 2.30.1 whereas I
> already have 2.31.90 (so it should have been fixed?). Maverick has 2.31.90.
> 
> I will try to install Cheese from GIT on Lucid.

Git master is the playground for the new 3.0 Cheese version, you should either checkout gnome-2-32 branch or get a tarball from 
http://ftp.acc.umu.se/pub/GNOME/sources/cheese/2.31/ (or wait for 2.31.91 to be included in the repos, which should happen soon).

> Also, I am wondering why Cheese could not just save the mjpeg stream like
> GUVCViewer does ? 
> (even optionally via Preferences..)

The thing here is that many different webcams stream data in different exotic formats, sometimes they advertise mjpeg but they provide some custom jpeg data that needs special case handling, sometimes they just stream in some custom format that needs dedicated decoding paths.

This problem of video formats proliferation handling has been fixed in linux with the advent of libv4l, a userspace library that transparently decodes all the video formats provided by v4l devices giving us nice rgb/yuv data.

Supporting mjpeg for your particular webcam will solve your problem but will probably prevent us to use libv4l posing a whole new series of issues with other camera devices.

I can confirm this problem, same thing happens to me with a LifeCam Cinema from Microsoft (https://www.microsoft.com/hardware/en-us/p/lifecam-cinema/H5D-00001).

There's no problem taking pictures, but the interface freezes the moment I click on the button to start recording video: the video preview goes black and the whole window freezes (it gets grey). There's no way to get out of that status, you either force the application to close or it'll close itself after some time. However, even freezing, sometimes it outputs a video file, but it's super choppy and the audio isn't in sync. Picture mode, preview and everything else works all right, though, this issue only happens when you try to record video.

I thought the problem might be related to sound recording so I tried recording video with different audio inputs, by selecting them in GNOME's sound preferences: the webcam's built-in mic, my desktop mic and finally without sound. The result was the same in all cases: Cheese kept freezing when I hit the button to record video.

Please note that in this case it is NOT a slow CPU problem: this happens on a desktop computer, Intel Core 2 Duo E6750 @ 2.66GHz with 6Gb of RAM.

I'm using Cheese 2.30.1.

Someone said before this is not relevant, but just in case: the camera seems to work just fine with guvcview.

I can provide additional info if you need so.

*** This bug has been marked as a duplicate of bug 564957 ***