933154 - [B2G][Helix][camera][dingyu]Start the video recording failed

Status: RESOLVED WORKSFORME

(Firefox OS Graveyard :: Gaia::Camera, defect, P3)

Description

[lecky]

User Agent: Mozilla/5.0 (Windows NT 6.1) AppleWebKit/535.1 (KHTML, like Gecko) Chrome/13.0.782.112 Safari/535.1

Steps to reproduce:

1. open the camera and toggle to video mode
2. press the caputre button to start a video recording 
3. press the home key to make the camera work in background 
4. press the camera button and go back to the camera 
5. repeat 2 ~ 4 quickly



Actual results:

a dialog box show that "Video not recorded, An error prevented Camera from recording the video"


Expected results:

start recording successfully

Comment 1

[lecky]

According to the log:
nsresult mozilla::nsGonkCameraControl::SetupRecording(int, int, int64_t, int64_t):1320 : mCameraHw is null
It means the mCameraHw is null, so the api startRecording return false and the dialog box appeared.

Compare the normal log and abnormal log I find that:
mCameraHw is define in GonkCameraControl.cpp L239: mCameraHw = GonkCameraHardware::Connect(this, mCameraId);(I am not sure of that)
According to the log, when the issue happens, the time of define "mCameraHw" is after than the judgment RETURN_IF_NO_CAMERA_HW in function "nsGonkCameraControl::SetupRecording"(in GonkCameraControl.cpp).

I try to find the original location to call "mCameraHw = GonkCameraHardware::Connect" and "nsGonkCameraControl::SetupRecording". But I am sorry I only find that:
"mCameraHw = GonkCameraHardware::Connect" is from "nsDOMCameraManager::GetCamera()" (in DomCameraManger.cpp)
"nsGonkCameraControl::SetupRecording" is from "nsDOMCameraControl::StartRecording"(in DomCameraControl.cpp)

So in my opinion, the reason is as follow: when I open the camera, nsDOMCameraManager::GetCamera will go and the mCameraHw  will be defined. Because of my pressing the capture button so quickly that at the time "RETURN_IF_NO_CAMERA_HW " to check the mCameraHw, actually the "mCameaHw" have not be defined.

Comment 2

[lecky]

I think in camera.js we set some time delay befor we call the api "startRecording". it maybe helpful.

Comment 3

[Wayne Chang [:wchang]]

Not blocking HD.

Vincent, can you check this and nominate for koi if you think the fix is worth it?

Comment 4

[Sotaro Ikeda [:sotaro]]

(In reply to lecky from comment #1)
> 
> Compare the normal log and abnormal log I find that:
> mCameraHw is define in GonkCameraControl.cpp L239: mCameraHw =
> GonkCameraHardware::Connect(this, mCameraId);(I am not sure of that)

This function get camera hw ownership from CameraService in android mediaserver. If this function failed, the problem happens in CameraService side.

Comment 5

[Sotaro Ikeda [:sotaro]]

(In reply to lecky from comment #2)
> I think in camera.js we set some time delay befor we call the api
> "startRecording". it maybe helpful.

I do not think it is a good idea without analyzing the actual cause of the problem.

Comment 6

[Mike Habicher [:mikeh] (high bugzilla latency)]

I think the solution is that the 'visibilitychange' event handler[1] needs to call disableButtons() to make sure we can't tap on the start-recording button until the preview has restarted.

1. https://github.com/mozilla-b2g/gaia/blob/master/apps/camera/js/camera.js#L1540

Comment 7

[Mike Habicher [:mikeh] (high bugzilla latency)]

Attachment: WIP - disable camera buttons when it goes into the background, v1

lecky, can you try out this patch?

Comment 9

[lecky]

(In reply to Sotaro Ikeda [:sotaro] from comment #4)

> This function get camera hw ownership from CameraService in android
> mediaserver. If this function failed, the problem happens in CameraService
> side.
In my opinion, the function get camera hw ownership doesn't failed. Because I use continuous auto focus in preview, so If i open the camera then press the capture button quickly, the api "startRecording" is running quickly. In my thought, the reason of the problem is that when I open the camera the function "navigator.mozCameras.getCamera" will call to define mCameraHw, before the mCameraHw is defined, "RETURN_IF_NO_CAMERA_HW " is called. 
  I think Camera.disableButtons(); add after https://github.com/mozilla-b2g/gaia/blob/master/apps/camera/js/camera.js#L1540 will more better? do you think so?

Comment 10

[Mike Habicher [:mikeh] (high bugzilla latency)]

lecky, have you tried the above patch (or your suggestion in comment 9)?

Comment 11

[lecky]

(In reply to Mike Habicher [:mikeh] from comment #10)
> lecky, have you tried the above patch (or your suggestion in comment 9)?

Mike I have try the patch, the probability become small, but the problem is still exist.But if I merge the patch, when it failed, the log is not the same as previous.

Comment 12

[Diego Marcos [:dmarcos]]

This does not reproduce anymore:

Gaia      6a1373340b40fcfe901336bc9e80676e5f2ba979
Gecko     https://hg.mozilla.org/releases/mozilla-aurora/rev/82ef9bf64d87
BuildID   20140626000202
Version   32.0a2

Please reopen if you're able to reproduce.