vp8/encoder/x86/denoising_sse2.c:35:10: error: taking the absolute value
of unsigned type 'unsigned int' has no effect [-Werror,-Wabsolute-value]
Change-Id: I749ba8e6f55dbd9b822bfd4260a8397554f5e524
C version and sse2 version, and off by default.
For the test clip used, the sse2 performance improved by ~5.6%
Change-Id: Ic2d815968849db51b9d62085d7a490d0e01574f6
If the denoiser filter causes too big a change in the absolute pixel difference
(between source and denoised signal), the block is not denoised, which can cause
visual block artifacts. This change applies a second adjustment to the temporal filter
to effectively allow for a (weaker) denoising for such blocks (which can keep
the absolute differnence within the tolerance range in most cases).
This helps to reduce some of the block artifacts from the denoising.
The additional cost of re-applying the filter to this set of blocks is low,
as the percentage of blocks per frame (with too big a change in absolute pixel difference)
is typically small, 2-5%.
Change-Id: Id9b56e59e33f3c22e79d2f89f763bdde246fdf3f
The denoiser function was modified to reduce the computational
complexity.
1. The denoiser c function modification:
The original implementation calculated pixel's filter_coefficient
based on the pixel value difference between current raw frame and last
denoised raw frame, and stored them in lookup tables. For each pixel c,
find its coefficient using
filter_coefficient[c] = LUT[abs_diff[c]];
and then apply filtering operation for the pixel.
The denoising filter costed about 12% of encoding time when it was
turned on, and half of the time was spent on finding coefficients in
lookup tables. In order to simplify the process, a short cut was taken.
The pixel adjustments vs. pixel diff value were calculated ahead of time.
adjustment = filtered_value - current_raw
= (filter_coefficient * diff + 128) >> 8
The adjustment vs. diff curve becomes flat very quick when diff increases.
This allowed us to use only several levels to get a close approximation
of the curve. Following the denoiser algorithm, the adjustments are
further modified according to how big the motion magnitude is.
2. The sse2 function was rewritten.
This change made denoiser filter function 3x faster, and improved the
encoder performance by 7% ~ 10% with the denoiser on.
Change-Id: I93a4308963b8e80c7307f96ffa8b8c667425bf50
Allows building the library with the gcc -pedantic option, for improved
portabilty. In particular, this commit removes usage of C99/C++ style
single-line comments and dynamic struct initializers. This is a
continuation of the work done in commit 97b766a46, which removed most
of these warnings for decode only builds.
Change-Id: Id453d9c1d9f44cc0381b10c3869fabb0184d5966
Compares the sum of differences between the input block and the averaged
block. If they differ too much the block will not be filtered. Negligible
perfomance hit.
Change-Id: Ib1c31a265efd4d100b3abc4a1ea6675038c8ddde
