RESOLVED FIXED 78386
Round off error in setValueCurveAtTime 
https://bugs.webkit.org/show_bug.cgi?id=78386
Summary Round off error in setValueCurveAtTime
Raymond Toy
Reported 2012-02-10 14:03:34 PST
There is a round-off error in setValueCurveAtTime. When calling setValueCurveAtTime(curve, 0.0, 0.3) with a sample rate of 44100 and the curve data being sample-frame spaced of exactly the right length, the output has one sample duplicated, causing the rest of the values to be shifted. This is caused by a roundoff error at the line: unsigned curveIndex = static_cast<unsigned>(curveVirtualIndex); In this particular example, curveVirtualIndex = 895.9999 instead of 896 due to roundoff. The curveIndex is set to 895 which causes curve[895] to be output. But it was already output the previous time, so the output is duplicated and the output has the curve values shifted by one. Rounding curveVirtualIndex instead of truncating fixes this.
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Raymond Toy
Comment 1 2012-02-21 14:22:31 PST
It might be easiest to fix this in bug 77666, which is how this error was found.
Raymond Toy
Comment 2 2012-03-02 09:58:02 PST
This was fixed in bug 77666. Closing this out now.
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