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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

#21

Post by Xcelerate »

huhtenberg wrote: post #16

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 th…

Haha, I only kind of skimmed your post then downloaded that file. I opened the images and was like "I don't know how high-quality this is. The images look exactly the same to me." And then I saw the file sizes and had the ah-ha moment.

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

#22

Post by Xcelerate »

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.

I wrote a JPEG encoder once, and if I remember correctly you can change the quantization tables and the Huffman tables. My encoder just used the default tables in the standard, but it wouldn't surprise me to optimize these using a psychovisual fitness function.

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

#23

Post by Daiz »

As others have noted, Beamr's "magical" technology simply seems to be using x264, the state-of-the-art in H.264 encoders, which also happens to be free and open source software. Looking at their site, beamrvideo.com, the bitrates they list for the originals are what you'll typically find on Blu-ray discs, not on online streams. Anyone who knows a thing or two about video encoding and x264 will know that you can re-encode these to a much smaller size while retaining most of the visual quality. As such, claiming that they can reduce the bitrate to half with no notable loss in quality is like claiming that you can reduce the bit depth and sampling rate of a 24-bit 192 kHz audio file to 16-bit 48 kHz with no notable loss in quality - it's certainly true, but you hardly needed the 24-bit 192 kHz quality to begin with.

They don't seem to have done anything new or substantial by themselves, and as such, this thing is basically nothing but pure marketing bullshit. If you want to do high quality H.264 encodes, just use x264 directly.

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

#24

Post by deadairspace »

huhtenberg wrote: post #16

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 th…

I don't see much of a difference. Is that the point? Are you saying that JPEGMini are just compressing to ~83% quality?

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

#25

Post by Daiz »

gmartres wrote: post #19

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 in…

>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.

I'm up for that. It'll take a while to download all the source videos, but I'll report back with results and videos when I'm done.

I already did a test encode with x264 --preset veryslow --tune film --level 4.0 --crf 21 on the Bourne Identity clip, and the result is within the same realm than the Beamr video with ~58% the filesize. Which is not surprising at all, considering Beamr's settings.

EDIT: Testing with nearly identical settings (x264 --bframes 0 -- subme 8 --no-psy --no-mbtree) using the latest x264 gives me about 40% the bitrate of the Beamr example for the Bourne Identity clip, which unsurprisingly looks notably worse. So maybe Beamr's "magical" encoding technology is all about fiddling with x264's CRF to make it double the bitrate at a given value compared to vanilla x264?

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

#26

Post by ricardobeat »

huhtenberg wrote: post #16

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 th…

JPEGmini better preserves color information, but it doesn't seem to be that much better.

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

#27

Post by huhtenberg »

deadairspace wrote: post #24
huhtenberg wrote: post #16

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 th…

I don't see much of a difference. Is that the point? Are you saying that JPEGMini are just compressing to ~83% quality?

No, there is a noticeable difference.

JPEGMini diff shows less color fringing (fewer "colored" pixels) and it also appears to better preserve edges and outlines.

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

#28

Post by conroe64 »

huhtenberg wrote: post #16

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 th…

Maybe I'm not the most knowledgeable guy here, but I really don't see what you're getting at. The per-pixel diffs look nearly the same. I downloaded the "hipnshoot.zip" and yes the photos look identical. But then I fired up gimp and re-compressed the high quality photo to reduce the size even more than the "jpegmini" version, and I can't tell the difference. Here are the file sizes:

-rw-r--r-- 1 tim users 4930482 Dec 1 21:22 hipnshoot.jpg

-rw-r--r-- 1 tim users 1310430 Feb 26 08:27 hipnshoot_gimp.jpg

-rw-r--r-- 1 tim users 1352882 Dec 3 09:16 hipnshoot_mini.jpg

I put them here: http://www.rareventure.com/jpegmini/

"hipnshoot_mini.jpg" is the "jpegmini" version and "hipnshoot_gimp.jpg" is the one I compressed with plain old gimp.

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

#29

Post by Tuna-Fish »

lutusp wrote: post #18

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.

They appear to be using modern x264. This does outperform most (all?) commercial H.264 encoders to the degree they claim, so their claims can have merit.

However, this also means that if you want better encoding, you can just grab x264 and do it yourself.

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

#30

Post by mnicole »

huhtenberg wrote: post #16

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 th…

I'm not sure how much it could change anything here, but Imgur also compresses images when uploaded. Maybe try min.us?
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