In the above pictures we can see that all the differences between x264 4 MBps (4k) High Profile and VP8 are smaller.
And, in my opinion, most of all on the 3rd row, the VP8 images details
are sharper than x264. The fact that both PSNR and SSIM say that VP8 is
of very good quality, can be seen in the third row: the details and the
shapes look much more clear to me in VP8 video.
Shark
Below the pictures of Shark scene:
This time I've used ivfenc as well to encode VP8.
I did specify the following options:
./ivfenc in.yuv out.ivf \
--i420 -w 1280 -h 720 -p 2 -t 4 \
--best --target-bitrate=4000 --end-usage=0 \
--auto-alt-ref=1 --timebase=1000/25000 -v \
--minsection-pct=5 --maxsection-pct=800 \
--lag-in-frames=16 --kf-min-dist=0 --kf-max-dist=360 \
--token-parts=2 --static-thresh=0 --drop-frame=0 \
--min-q=0 --max-q=60
And indeed in the following charts you can find VP8 4k --best as the video encoded with ivfenc (which paradoxally was even faster than ffmpeg), while VP8 4k is as above VP8 encoded with ffmpeg.
PSNR:
SSIM:
The Shark scene shows us that when using a VP8 encoder with options to tune output for more quality, VP8 4k --best competes straight with normal x264 4k, and sometimes it's at level of x264 4k HP (High Profile).
And considering that according to other people
this encoder is still raw, badly implemented with poor code, the above
charts are definitely not bad, if you know what I mean ;-)
Hey, I've heard about XviD and Theora video codecs, what about them?
Just to show you a comparisno between the new codecs (VP8, x264) and
old ones (XivD, Theora), below are PSNR and SSIM of scene one with 4
MBps rate.
I hope the charts speak for themselves:
Now, if for the PSNR chart we can see that x264 and VP8 are mainly
better than XviD and Theora (but not so extreme difference) in the SSIM
chart we can grasp (and measure) that both Theora and XviD lag behind
quite a lot.
And this is not unexpected; when watching the scenes encoded with XviD
and/or Theora, you feel you'd need a lot more bitrate to achieve same
quality as in VP8 and/or x264.
And yes, for HD content Theora is not good. Simple.
What can I say?
Well, given that in many occasions PSNR and SSIM aren't far away between x264 and VP8, VP8 is a fair competitor for x264.
Indeed, currently (Jun 2010) the badly implemented VP8 encoder (--best
option in ivfenc) offers same quality as x264 normal. Which is pretty
good considering the fact that there's room for improvement.
Would I use VP8 now to save my HD videos? Not really, because ffmpeg
0.6 is extremely slow (6+ FPS on my 4 cores AMD x4 965 B.E.), and
doesn't use all
of my 4 cores, while Handbrake is faster ( 60+ FPS) and uses 4 corse
100% each. And even if ivfenc is faster than ffmpeg there is still the
question about playing videos on other devices which at the moment
don't support VP8.
So, from my viewpoint, VP8 is not usable in production right now, but once it'll be better
implemented (and maybe the encoder will manage to better save
background details) VP8, given the patent free nature of this format,
could become the real standard.
- Compression speed: in this case the real winner is x264; VP8
code needs much more improvement to be comptetitive (at least using
ffmpeg, ivfenc needs improvements as well).
- Patents and royalties: well clearly VP8 is the winner here,
without chance for x264 to ever come near. Unless MPEG L.A. decides to
make it become a royalty free standard (which I definitely doubt as
seen as they make money out of patents).
- Quality: they are sort of tied now, x264 is slightly better
in more static scenes while VP8 is better for highly dynamic ones. But
when proper encoders will be available for VP8 probably we'll see it
fill (at least some) the gap in less dynamic scenes.
- Hardware accelleration: this was one of the major publicity
stun that was lacking for other video formats than x264 (h.264 to be
specific). But now a lot of companies have announced hardware support
for VP8.
Final words
At the moment x264 is having the edge because is a very good encoder,
stable since some years and really implements the h.264 standard inside
out. In a nice way indeed.
VP8 is like rough gold, it needs to be primed, in the code and perhaps some details algorithm search as well.
But give VP8 some time, I feel that this one could be a real
liberation (and evolution if I may say) from a heavily patented codec.
If you want to have a word, please contact me at ema at _fast_web_net.it (remove the _ otherwise email address won't work).
Disclaimer
This comparison has been done just for the purpose of it. The author is not affiliated with any cited organization.
Avatar is © 2009 Twentieth Century Fox Film Corporation and
Dune Entertainment LLC. All Rights Reserved, © 2010 Twentieth Century
Fox Home Entertainment LLC. All Rights Reserved.
Shark is Copyright © 2010 Apple Inc. All rights reserved.
The above images have been used for citing purpose; in case the owner
of the above images wants to remove them, please contact the above
email address.