avutil/common: add av_rint64_clip
The rationale for this function is reflected in the documentation for it, and is copied here: Clip a double value into the long long amin-amax range. This function is needed because conversion of floating point to integers when it does not fit in the integer's representation does not necessarily saturate correctly (usually converted to a cvttsd2si on x86) which saturates numbers > INT64_MAX to INT64_MIN. The standard marks such conversions as undefined behavior, allowing this sort of mathematically bogus conversions. This provides a safe alternative that is slower obviously but assures safety and better mathematical behavior. API: @param a value to clip @param amin minimum value of the clip range @param amax maximum value of the clip range @return clipped value Note that a priori if one can guarantee from the calling side that the double is in range, it is safe to simply do an explicit/implicit cast, and that will be far faster. However, otherwise this function should be used. avutil minor version is bumped. Reviewed-by: NRonald S. Bultje <rsbultje@gmail.com> Signed-off-by: NGanesh Ajjanagadde <gajjanagadde@gmail.com>
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