25672 2014-05-12 23:55:44 +0000 Need to define what happens when putImageData is passed an ImageData whose .data's ArrayBuffer has been neutered 2014-05-15 18:40:20 +0000 1 1 1 Unclassified WHATWG HTML unspecified Other other RESOLVED FIXED http://www.whatwg.org/specs/web-apps/current-work/#dom-context-2d-putimagedata P3 normal Unsorted 1 contributor ian bzbarsky ian mike contributor oldest_to_newest 105786 0 contributor 2014-05-12 23:55:44 +0000 Specification: http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html Multipage: http://www.whatwg.org/C#dom-context-2d-putimagedata Complete: http://www.whatwg.org/c#dom-context-2d-putimagedata Referrer: http://www.whatwg.org/specs/web-apps/current-work/multipage/ Comment: Need to define what happens when putImageData is passed an ImageData whose .data's ArrayBuffer has been neutered Posted from: 63.245.221.34 by bzbarsky@mit.edu User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:32.0) Gecko/20100101 Firefox/32.0 105790 1 bzbarsky 2014-05-12 23:58:32 +0000 In particular, putImageData seems to assume that the width and height of the ImageData argument determine how much data is available (in particular, that there are width*height*4 bytes of data), but if the ArrayBuffer as been neutered that's just not the case. This is not handled by the behavior ES6 defines for neutered ArrayBuffers, because the only spec text here is: copy the four channels of the pixel with coordinate (x, y) in the imagedata data structure to the pixel with coordinate (dx+x, dy+y) which doesn't actually define how the "four channels of the pixel" are extracted from the ImageData... 105887 2 ian 2014-05-13 18:33:49 +0000 That text is referencing the earlier text definign "a Canvas Pixel ArrayBuffer". I've tried to make that mildly clearer. But yeah, either way neutered ImageData data isn't mentioned. I've updated putImageData() and createImageBitmap() to throw in this particular situation. I left the createImageData() method that takes an ImageData alone since it doesn't actually reference the data. 105890 3 contributor 2014-05-13 18:39:43 +0000 Checked in as WHATWG revision r8629. Check-in comment: Define how to handle neutered ImageData objects http://html5.org/tools/web-apps-tracker?from=8628&to=8629 105891 4 bzbarsky 2014-05-13 18:43:09 +0000 Thanks! "A Canvas Pixel ArrayBuffer is an ArrayBuffer that whose data " has a stray "that", I think. 106068 5 ian 2014-05-15 18:39:52 +0000 Oops. Thanks. Fixed. 106069 6 contributor 2014-05-15 18:40:20 +0000 Checked in as WHATWG revision r8637. Check-in comment: Typo in canvas section http://html5.org/tools/web-apps-tracker?from=8636&to=8637