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f8bfd5cd1e
kLevelsFromDelta[sharpness][delta] is an inverse look-up table that tells the minimum filtering strength needed to trigger the filtering of a step with amplitude 'delta'. We use this table in various situations: a) when computing the initial (/global) filtering strength for each segment. We look at the quantization step and deduce the proper filtering strength needed to result this quantization noise (talking the -f option into account). b) during intra16 calculation, when a block ends up very empty (only DC coeffs are non-zero, all ACs have vanished). We'll rely on the in-loop filtering to restore the smoothness (if the source was gradient-like smooth. That's why we look at the distortion too before triggering the filtering). Step b) goes _in addition_ to a), potentially raising the filtering strength if blockiness is likely. Change-Id: Icaeca93ef21da195b079e6587a44d9edfc8e9efa |
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| .. | ||
| alpha.c | ||
| analysis.c | ||
| backward_references.c | ||
| backward_references.h | ||
| config.c | ||
| cost.c | ||
| cost.h | ||
| filter.c | ||
| frame.c | ||
| histogram.c | ||
| histogram.h | ||
| iterator.c | ||
| layer.c | ||
| Makefile.am | ||
| picture.c | ||
| quant.c | ||
| syntax.c | ||
| token.c | ||
| tree.c | ||
| vp8enci.h | ||
| vp8l.c | ||
| vp8li.h | ||
| webpenc.c | ||