74600 2011-12-15 04:29:57 -0800 [Qt] Graphics are pixelated after scaling/rotating 2013-04-11 09:21:47 -0700 1 1 1 Unclassified WebKit WebKit Qt 528+ (Nightly build) PC Windows XP RESOLVED FIXED P3 Major --- 113405 0 magnesus2 webkit-unassigned allan.jensen ivan4th magnesus2 oldest_to_newest 521822 0 magnesus2 2011-12-15 04:29:57 -0800 Transforming images in QtWebKit from Qt 4.8.0 (QtWebKit 2.2.1) gives a pixelated image that after a second switches to smooth version. It looks very bad. It's on Windows XP using Qt 4.8.0. Steps to reproduce: scale a PNG image in img tag. Watch how it behaves after scaling. 521823 1 magnesus2 2011-12-15 04:31:17 -0800 The same graphics are always smoothly transformer with the same settings on Qt 4.7.0. 523277 2 magnesus2 2011-12-17 01:02:04 -0800 *smoothly transformed 536390 3 magnesus2 2012-01-16 00:09:17 -0800 Will this be resolved soon? I have to decide if to stick with Qt or change to sth different because of this issue. More info: When transforming - rotating, scaling or even moving PNG images in QtWebKit they are pixelated for a long while and then suddently they are smooth. 549790 4 magnesus2 2012-02-06 00:38:32 -0800 Still present in latest Qt4.8.0 (QtWebKit.dll has 4.9.0 version). 549804 5 magnesus2 2012-02-06 00:52:22 -0800 Here is a before, after image: http://wieza.iq.pl/beforeafter.png (left: when the image is moving, right: half a second after it stops). 549808 6 magnesus2 2012-02-06 01:05:12 -0800 I also found this bug reports: https://bugs.webkit.org/show_bug.cgi?id=41036 http://codereview.chromium.org/2881020/show Maybe they are related? 549809 7 magnesus2 2012-02-06 01:06:02 -0800 http://code.google.com/p/chromium/issues/detail?id=55495 557958 8 magnesus2 2012-02-16 00:15:44 -0800 Does anyone even read these? 649062 9 147551 ivan4th 2012-06-14 04:23:10 -0700 Created attachment 147551 workaround (patch) I was affected by that problem too. When using sprite-based animation (rapidly changing backgrounds) the animated image becomes pixelated during frame changes. I've changed GraphicsContextQt.cpp so it always uses QPainter::SmoothPixmapTransform. After that change the problem with non-smooth scaling disappeared and I didn't notice any performance hit. Your mileage may vary though. 649063 10 ivan4th 2012-06-14 04:25:48 -0700 Note that my patch isn't meant for inclusion in QtWebKit, it's just a temporary fix for the problem (thus it comments out some lines). 864409 11 allan.jensen 2013-03-27 04:44:43 -0700 This sounds like intentional behavior. Using low interpolation during animations, and high when it is finished. That is done for performance reasons. To avoid this, you need accelerated compositing which is enabled by default in Qt 5 and QtWebKit 2.3. 864503 12 allan.jensen 2013-03-27 07:06:48 -0700 (In reply to comment #11) > This sounds like intentional behavior. Using low interpolation during animations, and high when it is finished. That is done for performance reasons. > > To avoid this, you need accelerated compositing which is enabled by default in Qt 5 and QtWebKit 2.3. Forget that. I am going to make it configurable, see bug 113405. 873867 13 allan.jensen 2013-04-11 09:21:47 -0700 With the fix for bug #113405 landed. I will consider the issue fixed. The current default behavior is working as designed, and can now be disabled with image-rendering: optimizeQuality (or image-rendering: smooth as it will be called in CSS4 Images when that gets activated). 147551 2012-06-14 04:23:10 -0700 2012-06-14 04:23:10 -0700 workaround (patch) webkit-image-quality-workaround-patch.diff text/plain 2065 ivan4th LS0tIC4vc3JjLzNyZHBhcnR5L3dlYmtpdC9Tb3VyY2UvV2ViQ29yZS9wbGF0Zm9ybS9ncmFwaGlj cy9xdC9HcmFwaGljc0NvbnRleHRRdC5jcHAub3JpZwkyMDEyLTA2LTE0IDE0OjU2OjM1LjMyMTkx Njg3MyArMDQwMAorKysgLi9zcmMvM3JkcGFydHkvd2Via2l0L1NvdXJjZS9XZWJDb3JlL3BsYXRm b3JtL2dyYXBoaWNzL3F0L0dyYXBoaWNzQ29udGV4dFF0LmNwcAkyMDEyLTA2LTEzIDIzOjA0OjM3 LjIzMzA0Nzc4NiArMDQwMApAQCAtMjQzLDYgKzI0Myw3IEBACiAgICAgaW5pdGlhbFNtb290aFBp eG1hcFRyYW5zZm9ybUhpbnQgPSBwYWludGVyLT50ZXN0UmVuZGVySGludChRUGFpbnRlcjo6U21v b3RoUGl4bWFwVHJhbnNmb3JtKTsKIAogICAgIHBhaW50ZXItPnNldFJlbmRlckhpbnQoUVBhaW50 ZXI6OkFudGlhbGlhc2luZywgdHJ1ZSk7CisgICAgcGFpbnRlci0+c2V0UmVuZGVySGludChRUGFp bnRlcjo6U21vb3RoUGl4bWFwVHJhbnNmb3JtLCB0cnVlKTsKIH0KIAogR3JhcGhpY3NDb250ZXh0 UGxhdGZvcm1Qcml2YXRlOjp+R3JhcGhpY3NDb250ZXh0UGxhdGZvcm1Qcml2YXRlKCkKQEAgLTEz NzEsMjUgKzEzNzIsMjYgQEAKIHZvaWQgR3JhcGhpY3NDb250ZXh0OjpzZXRJbWFnZUludGVycG9s YXRpb25RdWFsaXR5KEludGVycG9sYXRpb25RdWFsaXR5IHF1YWxpdHkpCiB7CiAgICAgbV9kYXRh LT5pbWFnZUludGVycG9sYXRpb25RdWFsaXR5ID0gcXVhbGl0eTsKKyAgICBtX2RhdGEtPnAoKS0+ c2V0UmVuZGVySGludChRUGFpbnRlcjo6U21vb3RoUGl4bWFwVHJhbnNmb3JtLCB0cnVlKTsKIAot ICAgIHN3aXRjaCAocXVhbGl0eSkgewotICAgIGNhc2UgSW50ZXJwb2xhdGlvbk5vbmU6Ci0gICAg Y2FzZSBJbnRlcnBvbGF0aW9uTG93OgotICAgICAgICAvLyB1c2UgbmVhcmVzdC1uZWlnYm9yCi0g ICAgICAgIG1fZGF0YS0+cCgpLT5zZXRSZW5kZXJIaW50KFFQYWludGVyOjpTbW9vdGhQaXhtYXBU cmFuc2Zvcm0sIGZhbHNlKTsKLSAgICAgICAgYnJlYWs7Ci0KLSAgICBjYXNlIEludGVycG9sYXRp b25NZWRpdW06Ci0gICAgY2FzZSBJbnRlcnBvbGF0aW9uSGlnaDoKLSAgICAgICAgLy8gdXNlIHRo ZSBmaWx0ZXIKLSAgICAgICAgbV9kYXRhLT5wKCktPnNldFJlbmRlckhpbnQoUVBhaW50ZXI6OlNt b290aFBpeG1hcFRyYW5zZm9ybSwgdHJ1ZSk7Ci0gICAgICAgIGJyZWFrOwotCi0gICAgY2FzZSBJ bnRlcnBvbGF0aW9uRGVmYXVsdDoKLSAgICBkZWZhdWx0OgotICAgICAgICBtX2RhdGEtPnAoKS0+ c2V0UmVuZGVySGludChRUGFpbnRlcjo6U21vb3RoUGl4bWFwVHJhbnNmb3JtLCBtX2RhdGEtPmlu aXRpYWxTbW9vdGhQaXhtYXBUcmFuc2Zvcm1IaW50KTsKLSAgICAgICAgYnJlYWs7Ci0gICAgfTsK KyAgICAvLyBzd2l0Y2ggKHF1YWxpdHkpIHsKKyAgICAvLyBjYXNlIEludGVycG9sYXRpb25Ob25l OgorICAgIC8vIGNhc2UgSW50ZXJwb2xhdGlvbkxvdzoKKyAgICAvLyAgICAgLy8gdXNlIG5lYXJl c3QtbmVpZ2JvcgorICAgIC8vICAgICBtX2RhdGEtPnAoKS0+c2V0UmVuZGVySGludChRUGFpbnRl cjo6U21vb3RoUGl4bWFwVHJhbnNmb3JtLCBmYWxzZSk7CisgICAgLy8gICAgIGJyZWFrOworCisg ICAgLy8gY2FzZSBJbnRlcnBvbGF0aW9uTWVkaXVtOgorICAgIC8vIGNhc2UgSW50ZXJwb2xhdGlv bkhpZ2g6CisgICAgLy8gICAgIC8vIHVzZSB0aGUgZmlsdGVyCisgICAgLy8gICAgIG1fZGF0YS0+ cCgpLT5zZXRSZW5kZXJIaW50KFFQYWludGVyOjpTbW9vdGhQaXhtYXBUcmFuc2Zvcm0sIHRydWUp OworICAgIC8vICAgICBicmVhazsKKworICAgIC8vIGNhc2UgSW50ZXJwb2xhdGlvbkRlZmF1bHQ6 CisgICAgLy8gZGVmYXVsdDoKKyAgICAvLyAgICAgbV9kYXRhLT5wKCktPnNldFJlbmRlckhpbnQo UVBhaW50ZXI6OlNtb290aFBpeG1hcFRyYW5zZm9ybSwgbV9kYXRhLT5pbml0aWFsU21vb3RoUGl4 bWFwVHJhbnNmb3JtSGludCk7CisgICAgLy8gICAgIGJyZWFrOworICAgIC8vIH07CiB9CiAKIElu dGVycG9sYXRpb25RdWFsaXR5IEdyYXBoaWNzQ29udGV4dDo6aW1hZ2VJbnRlcnBvbGF0aW9uUXVh bGl0eSgpIGNvbnN0Cg==