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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

#31

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…

> (without credit)

Just to note, no credit is necessarily required. x264 is now dual-licensed under GPL2 + commercial license. If they bought a commercial license, there's nothing illegal or wrong in what they do.

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

#33

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…

> (without credit) Just to note, no credit is necessarily required. x264 is now dual-licensed under GPL2 + commercial license. If they bought a commercial license, there's nothing illegal or wrong in what they do.

>If they bought a commercial license, there's nothing illegal or wrong in what they do.

Looking into it, they seem to have actually done that. ICVT, the company behind Beamr, can be found on the list of x264 commercial adopters[1].

Doesn't change the fact that they're major Snake Oil Salesmen, though. Also, the claims on their technology page[2] are still incredibly dubious.

[1] http://x264licensing.com/adopters

[2] http://beamrvideo.com/main/technology

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

#34
post #25

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 resul…

Justin from Zencoder here... I've been doing a bit of similar testing and seeing similar results. So they're obviously controlling the settings per frame (or per segment) during the encode, meaning the values in that encoder line are not very useful in analyzing what they're doing.

I'm definitely seeing a loss in quality on the "mini" encodes relative to the source -- mostly in loss of grain, and fine details (in hair, etc).

However, if they're analyzing the motion within the video and using perceptual algorithms to determine what the focal points are, etc. then it's totally fair to throw away details in sections that are peripheral, and likewise getting rid of grain in a blurred-out portion of the screen that's panning makes sense if your eye wouldn't perceive that anyway. This seems to be a much more aggressive version of x264's "psy" optimizations, essentially.

So the resulting video might look very similar in quality to someone watching the movie, but not to someone analyzing the frames and details. There's a hard line to draw on how that's marketed -- it's not actually "without losing quality", but it might be "without looking worse"?

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

#35
post #34
post #25

Earlier quoted context omitted.

>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 resul…

Justin from Zencoder here... I've been doing a bit of similar testing and seeing similar results. So they're obviously controlling the settings per frame (or per segment) during the encode, meaning the values in that encoder line are not very useful in analyzing what they're doing. I'm definitely seeing a loss in quality on the "mini" encodes relative to the source -- mostly in loss of grain, and fine details (in hai…

Based on the comparing I've done on the second clip so far, they seem to be doing absolutely nothing special - at approximately the same bitrate and settings, the videos are practically identical quality-wise (in fact, the most recent x264 seems to fare a small bit better).

I'm going to do two sets of comparisons for each clip: Beamr's video compared to x264 with similar settings and bitrate, and then Beamr-like settings and high quality settings compared at a much more realistic bitrate that you would actually see in use in digital video on the internet.

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

#36
post #23

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-en…

[deleted]

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

#37
post #35
post #34

Earlier quoted context omitted.

Justin from Zencoder here... I've been doing a bit of similar testing and seeing similar results. So they're obviously controlling the settings per frame (or per segment) during the encode, meaning the values in that encoder line are not very useful in analyzing what they're doing. I'm definitely seeing a loss in quality on the "mini" encodes relative to the source -- mostly in loss of grain, and fine details (in hai…

Based on the comparing I've done on the second clip so far, they seem to be doing absolutely nothing special - at approximately the same bitrate and settings, the videos are practically identical quality-wise (in fact, the most recent x264 seems to fare a small bit better). I'm going to do two sets of comparisons for each clip: Beamr's video compared to x264 with similar settings and bitrate, and then Beamr-like sett…

I just came back to add that, encoding 2-pass to the same bitrate that theirs results at, I have a very hard time telling the difference. I look forward to your comparison sets.

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

#38
post #30

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?

PNG is lossless.

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

#39

>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.

Yes, but the default tables in the standard do mimic the human eye's limitations. That's what increasing the quant factor on higher frequencies is.

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

#40
post #25

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 resul…

I've finished my comparisons now. HN submission here: http://news.ycombinator.com/item?id=5289532
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