[Webkit-unassigned] [Bug 42370] New: Scaled Resized images are blurred when sent to Skia

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=42370

           Summary: Scaled Resized images are blurred when sent to Skia
           Product: WebKit
           Version: 528+ (Nightly build)
          Platform: PC
        OS/Version: Linux
            Status: UNCONFIRMED
          Severity: Normal
          Priority: P2
         Component: SVG
        AssignedTo: webkit-unassigned at lists.webkit.org
        ReportedBy: mabbo at chromium.org
                CC: zimmermann at kde.org


1. Have an SVG load an image at a lower quality than the actual image is at. (example: image is actually 512x512, but we load it with width=128 height=128)
2. Have the svg <image> tag include a transform that scales up the image, lets say back to it's original size. (example image tag has transform="scale(4)")

Result: The image is resampled down, as Skia assumes we're drawing it at the small size specified, then when we draw it, we're scaling it back up. We get the poor quality version we see here. And it only does this when using Skia versions of Chrome (which is why OSX Chrome has no issue). 

The problem is in WebCore/platform/graphics/skia/ImageSkia.cpp. 

When we have computeResamplingMode return RESAMPLE_AWESOME, we're scaling down the image. Having these conditions return RESAMPLE_LINEAR instead will ensure that we don't do the specific resampling that causes this issue, when these conditions arise. 

Patch to follow shortly that will check for later scaling in the canvas, and return RESAMPLE_LINEAR in that case.

-- 
Configure bugmail: https://bugs.webkit.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.