773989 - Seeking back in a video stream derived from getUserMedia results in an InvalidStateError

Status: RESOLVED DUPLICATE of bug 773988

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

Description

[Jason Smith [:jsmith]]

Attachment: Camera API Video Test

Steps:

1. Launch the test case attached
2. Show the controls for the video by right clicking it and selecting show controls
3. Seek backwards in the video while the video stream is being captured

Expected:

The video stream should return backwards to the time to the time I specified for when my video was captured from my camera.

Actual:

Lots of errors like the one below show up in the console:

Timestamp: 7/14/2012 12:31:39 PM
Error: InvalidStateError: An attempt was made to use an object that is not, or is no longer, usable
Source File: chrome://global/content/bindings/videocontrols.xml
Line: 755

The video also fails to go back to the time I specified in the past.

Comment 1

[Jason Smith [:jsmith]]

Analyzing the specification for getUserMedia, a MediaStream is not seekable. The error I think likely is being thrown since we are taking an action that in fact, is not allowed on the MediaStream API. So the error sounds like the behavior is expected and valid. Can someone confirm this?

The one thing I'm thinking about though is that the UI for firefox with html5 videos exposes a way to expose the controls, even though in fact, they expose functionality that's not allowed on a MediaStream. There might be a better way to clean this up, as we should be cautious to send a user to a UI that won't work with a MediaStream. Thoughts?