- From: <bugzilla@jessica.w3.org>
- Date: Sat, 25 Jun 2011 16:38:47 +0000
- To: public-html@w3.org
http://www.w3.org/Bugs/Public/show_bug.cgi?id=13060 Summary: Consider MJPG files like <video> when used as the image argument for drawImage() Product: HTML WG Version: unspecified Platform: PC OS/Version: All Status: NEW Severity: normal Priority: P2 Component: HTML Canvas 2D Context (editor: Ian Hickson) AssignedTo: ian@hixie.ch ReportedBy: david.humphrey@senecac.on.ca QAContact: public-html-bugzilla@w3.org CC: mike@w3.org, public-html-wg-issue-tracking@w3.org, public-html@w3.org Created attachment 1005 --> http://www.w3.org/Bugs/Public/attachment.cgi?id=1005 DrawImage test case with MJPG (traffic web cam) Currently, the canvas2d drawImage() spec says: "When the drawImage() method is passed an animated image as its image argument, the user agent must use the poster frame of the animation, or, if there is no poster frame, the first frame of the animation." It then goes on to discuss the special case of HTMLVideoElements: "When the image argument is an HTMLVideoElement, then the frame at the current playback position must be used as the source image, and the source image's dimensions must be the intrinsic width and intrinsic height of the media resource (i.e. after any aspect-ratio correction has been applied)." I'd like to suggest that MJPG files are often used in place of video, especially with security cameras and other web camera feeds. Some browser vendors already take the same position, for example Chrome and Safari, which will use the current image (frame) of the MJPG when it is passed to drawImage(). Firefox currently tries to do what the spec says, and load the first frame. I've filed a bug with Mozilla, as well: https://bugzilla.mozilla.org/show_bug.cgi?id=667206 I believe that WebKit's behaviour is useful and least surprising here, even though not spec compliant. I'd like to suggest that this behaviour be considered as the correct one for the spec going forward, and that spec be changed. I've included a simple test case. Thanks for considering this. -- Configure bugmail: http://www.w3.org/Bugs/Public/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.
Received on Saturday, 25 June 2011 16:38:53 UTC