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New Solution Can Cut Video File Size By Half – Without Losing Quality

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Re: New Solution Can Cut Video File Size By Half – Without Losing Quality

#11

Post by jfb »

ZeroGravitas wrote: post #10
pornel wrote: post #4

Earlier quoted context omitted.

AFAIK JPEGmini has much better psychovisual optimization than libjpeg, so I think their claim that they can compress JPEG better within limits of the format is fair. The way you encode lossy formats makes a lot of difference. For example the same x264 encoder gives dramatically worse results when aiming for optimal PSNR rather than using its psychovisual optimizer: • http://x264.nl/developers/Dark_Shikari/imagecoding…

Is it not a bit ironic to be linking to x264 developers to support the thesis that a new H.264 encoder can be twice as effective in compressing H.264 than the competition? Either they've done something magical and can outcompress x264 to that degree (i.e. in the ballpark of HEVC, yet without breaking compatability), or they're comparing against a terrible H.264 encoder and they've just wrapped x264 in a proprietary s…

It's undoubtedly bullshit.

Re: New Solution Can Cut Video File Size By Half – Without Losing Quality

#14

Post by josephlord »

Incremental improvements in H.264 are still possible but not a halving of bitrate in the general case. The required rate depends very much on the content of the video and the size at which it will be viewed.

Any encoder manufacturer can find some great looking and easy to encode images that can be massively reduced in data rate without much visible impact. However in tougher scenarios they will be unlikely to beat the existing market leaders by more than 10% or so under similar constraints (latentcy/CPU/multi-pass possible) under the review of experts. Tough scenarios will be when there is lots of noise and non-uniform movement. Pop concerts can be very challenging with crowd movements, flashing lights and low general light levels leading to noise.

Re: New Solution Can Cut Video File Size By Half – Without Losing Quality

#15

Post by Tloewald »

josephlord wrote: post #14

Incremental improvements in H.264 are still possible but not a halving of bitrate in the general case. The required rate depends very much on the content of the video and the size at which it will be viewed. Any encoder manufacturer can find some great looking and easy to encode images that can be massively reduced in data rate without much visible impact. However in tougher scenarios they will be unlikely to beat th…

The more detailed claim is 5-6Mbps streams can be reduced to 3-4, so it's more like a 25% improvement methinks.

Their first claimed success was with JPEGmini — this is a lot more credible since JPEG is a pretty obsolete format that simply continues because it's so well supported. JPEG2000 delivers the purported benefits of JPEGmini for real -- it's just poorly supported.

I suspect all they're really doing is fine-tuning compression settings based on differencing input and output using a decent perceptual algorithm.

I uploaded a photo straight out of a Nikon V1 onto JPEGmini and got a 2.2x reduction. I could do better than that by dialing down quality until I saw a difference. JPEG fine is way overkill for most purposes, and that's their market.

Re: New Solution Can Cut Video File Size By Half – Without Losing Quality

#16

Post by huhtenberg »

For the lazy - http://jpegmini.com

  --
I grabbed 4th pair of their demo image [0], the high quality image is about 4.8M, the JpegMini'd version - 1.3M.

Then I took the high quality image and started bumping up standard JPEG compression level until I reduced the file size to 1.3M. That mapped to 17/100 setting, with 1 being highest quality, 100 - highest compression).

Then I made an arithmetic per-pixel diff between the original high quality image and two 1.3M versions. Cropped them to 2000 x 2000 and saved as PNGs (cropping is to fit the imgur file size limits). Here they are -

http://imgur.com/1FOwXhq

http://imgur.com/3efRooj

Now, have a look and tell me that JPEGMini hasn't got something exciting going on.

--

[0] http://media.jpegmini.com/homepageImages/20121203/hipnshoot....

Re: New Solution Can Cut Video File Size By Half – Without Losing Quality

#18

Post by lutusp »

Let them put up a long, complex video -- an action movie, for example -- using H.264, and their own method, for side-by-side comparison, both with regard to quality and file size. Let them offer something better than hand-waving press releases.

I say this because claims like this tend to be very source-dependent. Change the source, change the claim.

Re: New Solution Can Cut Video File Size By Half – Without Losing Quality

#19

Post by gmartres »

From beamrvideo.com, Clip1_mini.mov contains:

  videomini ver. 90.15 options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=umh subme=8 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=10 qpmax=51 qpstep=4 ip_ratio=1.41 aq=1:1.00
And Clip2_mini.mov contains:

  videomini ver. 89.15 options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=umh subme=8 psy=0 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=0 threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc=crf mbtree=0 crf=23.0 qcomp=0.60 qpmin=10 qpmax=51 qpstep=4 ip_ratio=1.40 aq=1:1.00
For comparaison, here's what a clip encoded with x264 contains: x264 - core 125 r2200 999b753 - H.264/MPEG-4 AVC codec - Copyleft 2003-2012 - http://www.videolan.org/x264.html - options: cabac=1 ref=1 deblock=1:0:0 analyse=0x1:0x111 me=hex subme=5 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=0 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=2 keyint=240 keyint_min=23 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=2pass mbtree=1 bitrate=373 ratetol=1.0 qcomp=0.60 qpmin=10 qpmax=51 qpstep=4 cplxblur=20.0 qblur=0.5 ip_ratio=1.40 aq=1:1.00

So their encoder is based on x264 (without credit). The settings are slightly different between the clips, so maybe they have some magic thing to detect which settings to use. In any case, it'd be interesting to reencode the original clip using plain x264, once using the same options they used and once using some sane x264 preset.

Re: New Solution Can Cut Video File Size By Half – Without Losing Quality

#20

Post by Hari_Seldon »

mistercow wrote: post #13

>the compression method mimics the human eye and removes elements that would not have been processed by the human eye in the first place. That's just a marketing hype decsription of how all lossy compression works.

Agreed, reminds me of mp3.

>Elements of the recordings that are easily perceived are represented with exacting precision, while other parts that are not very audible can be represented less accurately. Meanwhile, inaudible information can be discarded altogether.

Fraunhofer Institute

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