Bug 225873 - Drawing an sRGB image into a DisplayP3 canvas and then into sRGB canvas yields different results than if you only draw it into the sRGB canvas
Summary: Drawing an sRGB image into a DisplayP3 canvas and then into sRGB canvas yield...
Status: RESOLVED MOVED
Alias: None
Product: WebKit
Classification: Unclassified
Component: Canvas (show other bugs)
Version: Other
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Nobody
URL:
Keywords: InRadar
Depends on:
Blocks:
 
Reported: 2021-05-17 08:47 PDT by Sam Weinig
Modified: 2021-08-11 10:11 PDT (History)
4 users (show)

See Also:

Attachments
Test case where both are drawn and tested (2.44 KB, text/html)
2021-05-17 08:48 PDT, Sam Weinig 		no flags Details
Test case where only the sRGB canvas is drawn into (2.45 KB, text/html)
2021-05-17 08:49 PDT, Sam Weinig 		no flags Details
Visual Test (all three squares should be the same color) (2.23 KB, text/html)
2021-05-17 09:06 PDT, Sam Weinig 		no flags Details
Visual Test (all three squares should be the same color) (2.16 KB, text/html)
2021-05-17 14:02 PDT, Sam Weinig 		no flags Details
Visual Test (only the sRGB ones) (2.16 KB, text/html)
2021-07-13 09:42 PDT, Sam Weinig 		no flags Details
Show Obsolete (1) 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 Sam Weinig 2021-05-17 08:47:29 PDT 
Drawing an sRGB image into a DisplayP3 canvas and then into sRGB canvas yields different results than if you only draw it into the sRGB canvas.
Comment 1 Sam Weinig 2021-05-17 08:48:59 PDT 
Created attachment 428832 [details]
Test case where both are drawn and tested
Comment 2 Sam Weinig 2021-05-17 08:49:27 PDT 
Created attachment 428833 [details]
Test case where only the sRGB canvas is drawn into
Comment 3 Sam Weinig 2021-05-17 08:50:31 PDT 
NOTE: This requires ToT WebKit with the CanvasColorSpacesEnabled feature enabled.
Comment 4 Sam Weinig 2021-05-17 08:52:29 PDT 
This seems to be related to some cache, as to see the results, you must open a new window for each test case, otherwise, the tests will taint each other.
Comment 5 Sam Weinig 2021-05-17 08:55:14 PDT 
It also seems to have to do with canvas accelerated graphics as disabling that (via the Debug -> Drawing and Compositing Flags, etc.) causes the issue to go away.
Comment 6 Sam Weinig 2021-05-17 09:06:26 PDT Comment hidden (obsolete)
Comment 7 Sam Weinig 2021-05-17 14:02:08 PDT 
Created attachment 428866 [details]
Visual Test (all three squares should be the same color)
Comment 8 Sam Weinig 2021-05-17 14:03:01 PDT 
Updated the visual test case, the getImageData() was not necessary. 

Now to uncover all the different image caches in WebKit to see which one is acting up.
Comment 9 Radar WebKit Bug Importer 2021-05-24 08:48:16 PDT 
<rdar://problem/78402035>
Comment 10 Sam Weinig 2021-07-13 09:42:06 PDT 
Created attachment 433411 [details]
Visual Test (only the sRGB ones)
Comment 11 Cameron McCormack (:heycam) 2021-08-10 22:20:16 PDT 
This is being tracked internally.
Comment 12 Sam Weinig 2021-08-11 10:11:50 PDT 
👍