Bug 156488 - putImageData needs to premultiply input
Summary: putImageData needs to premultiply input
Status: RESOLVED FIXED
Alias: None
Product: WebKit
Classification: Unclassified
Component: Canvas (show other bugs)
Version: WebKit Nightly Build
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Dean Jackson
URL:
Keywords: InRadar
Depends on:
Blocks:
 
Reported: 2016-04-11 19:43 PDT by Dean Jackson
Modified: 2016-04-11 19:57 PDT (History)
4 users (show)

See Also:

Attachments
Patch (4.94 KB, patch)
2016-04-11 19:49 PDT, Dean Jackson 		zalan: review+
Details | Formatted Diff | Diff
View All Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.
Description Dean Jackson 2016-04-11 19:43:52 PDT 
I made a mistake in r187534, where I updated putImageData to use the Accelerate framework. The iOS path accidentally unpremultiplied the incoming data, rather than premultiplying it.
Comment 1 Radar WebKit Bug Importer 2016-04-11 19:44:17 PDT 
<rdar://problem/25672675>
Comment 2 Dean Jackson 2016-04-11 19:45:11 PDT 
<rdar://problem/23119884>
Comment 3 Dean Jackson 2016-04-11 19:49:08 PDT 
Created attachment 276201 [details]
Patch
Comment 4 Jon Lee 2016-04-11 19:51:28 PDT 
What's the impact on the Animometer Images test?
Comment 5 Dean Jackson 2016-04-11 19:52:36 PDT 
(In reply to comment #4)
> What's the impact on the Animometer Images test?

Should be zero. We're still doing the same sets of operations, just multiplying rather than dividing. And this is iOS only.
Comment 6 Dean Jackson 2016-04-11 19:57:26 PDT 
Committed r199330: <http://trac.webkit.org/changeset/199330>