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New Super Resolution is ready.
December 13, 2013
This year we explored ways to accelerate and improve our Super Resolution engine,
and overall research, development and testing took much more time than we anticipated
but finally the new engine is available to our users. Today we're releasing it in
a form of VirtualDub plugin. DirectShow filter
is also ready, so after we change Video Enhancer to use the new version there
will be an update for Video Enhancer too. Also, an AviSynth plugin will be released soon.
Our advances in speed allow using it in video players to upsize videos to HD in
real time on modern PCs and laptops.
Generally quality and speed depend on source video and your CPU'a abilities, but here's
an example of changes between our old VirtualDub plugin (1.0) and the new one (2.0) on
a particular file (panasonic4.avi) when upsizing from 960x540 to 1920x1080 on an old
Quad Core 2.33 GHz:
Quality, in dB of Y-PSNR (higher is better):
version old new
fast mode 41.70 42.28
slow mode 42.07 42.73
Time of upsizing 200 frames, in seconds:
version old new_rgb new_yv12
fast mode 19.6 14.4 10.3
slow mode 28.7 19.5 14.0
Version 1.0 worked only in RGB32, so for YUV the speed was about the same as for RGB.
As you may see, the new version's fast mode provides similar quality to old version's
high-quality mode but does it 2-3 times faster depending on color space. And new
version's high-quality mode is still faster than old one's fast mode.
To achieve these speed gains our SR implementation was rewritten from scratch
to work block-wise instead of frame-wise. This way it doesn't need so much memory
to store intermediate results and intermediate data never leaves CPU cache,
avoiding spending so much time on memory loads and stores. Also, we learned to
use SSE2 vector operations better. Unfortunately even in 2013 compilers
still generally suck at vectorizing code, so it requires a lot of manual work.
tags: video_enhancer super_resolution
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