Created attachment 8750045 [details] Left side - buggy result by FF, right side - normal result by Chrome User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/50.0.2661.94 Safari/537.36 Steps to reproduce: There is gradient, where alpha change from 0 to 1. Apply filter feComponentTransfer, where <feFuncA type="linear" slope="10" intercept="0"></feFuncA> Actual results: Something happens with RGB-components. Visible posterization. See attached screenshots and test example: http://codepen.io/dom1n1k/pen/qZgrpr?editors=1100 Expected results: Slope 10 means to obtain values greater than 1 - they should be clamped (obviously). Other channels (RGB) should not be touched. Chrome and IE works fine. Spec: https://www.w3.org/TR/SVG/filters.html#feComponentTransferElement
Status: UNCONFIRMED → RESOLVED
Last Resolved: 2 years ago
Resolution: --- → DUPLICATE
Duplicate of bug: 930331
I'm not sure that this is a duplicate. Main question not about banding. Main question about influence feFuncA to other channels. I guess overflow after multiplication alpha channel to large multiplier (slope). Sorry for my bad english :)
I see banding on the left hand side. I'm not really sure I understand what else you're trying to say here.
Perhaps you could try to create a more obvious testcase?
Simplified example: http://codepen.io/dom1n1k/pen/ONdjWE 1. In gradient color is constant (orange). Alpha from 0 to 1. 2. Filter should change alpha channel only. 3. But we see changes in other channels (yellow instead orange). I suspect overflow. Banding - side effect.
Firefox does not support the color-interpolation CSS property. If I remove that Chrome and Firefox look the same. Is that the issue, if so we already have a color-interpolation bug.
Hmm. If I delete attributes color-interpolation and color-interpolation-filters, result is slightly different, but still obviously wrong. And not the same with Chrome. feFuncA should not change color (only alpha). But color was changed.
obviously wrong how?
Status: RESOLVED → UNCONFIRMED
Resolution: DUPLICATE → ---
I attached new picture. Chrome and IE look slightly different, but within rounding errors. Firefox - clearly different color. (testcase - http://codepen.io/dom1n1k/pen/ONdjWE)
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