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Okay then, you asked for it, so here you go. >The important thing regarding our technologies, and the main point you have missed in your analysis, is that they

by Daiz 14y ago

Okay then, you asked for it, so here you go. >The important thing regarding our technologies, and the main point you have missed in your analysis, is that they are used for automatic image optimization to the lowest bitrate or file size possible, and not for encoding an image or video to a specific bitrate or file size. This is exactly what the CRF mode in x264 is for. Now, in another comment you're claiming the following: >The decision Beamr Video makes are "smarter" than x264's CRF mode, since they are based on a perceptual quality measure we have developed. Let's see how well that measures up to reality then, shall we? For this comparison, I used the same four clips as earlier, and ran each of them against the following command line: x264 --crf 18.5 That's it. Completely default settings, with the exception of setting the CRF to 18.5 for everything. This shall be our vanilla x264 equivalent of your "technology that can adaptively reduce the bitrate of any clip to the minimum amount possible, while ensuring that quality of the output clip is perceptually identical to the quality of the input clip". Since we're using the same value for everything, it involves as much choosing on the user end as your service would. Now then, let's see how your "smarter than CRF" technology actually fares against x264's CRF. Here are the results: * Clip 1 - http://check2pic.ru/compare/26755/ http://check2pic.ru/compare/26755/ (CRF 18.5 encode is ~11.7% smaller) * Clip 2 - http://check2pic.ru/compare/26756/ http://check2pic.ru/compare/26756/ (CRF 18.5 encode is ~4.4% smaller) * Clip 3 - http://check2pic.ru/compare/26757/ http://check2pic.ru/compare/26757/ (CRF 18.5 encode is ~17% smaller) * Clip 4 - http://check2pic.ru/compare/26758/ http://check2pic.ru/compare/26758/ (CRF 18.5 encode is ~19.5% smaller) ( The full videos are available here: http://blisswater.info/video/beamr/set3/ http://blisswater.info/video/beamr/set3/ ) As we can see from the comparisons, x264, at defaults setting and CRF 18.5, can produce practically identical visual results (as in you wouldn't notice any quality difference in action), while producing smaller bitrates all over the board. Looks like your supposedly "smarter than CRF" technology for choosing bitrates isn't so smart after all, eh? In short, even if you have developed some sort of quality-based bitrate-choosing technology of your own, in practice it still seems to lose consistently to x264's CRF mode (and since x264 actually allows you to control the CRF value, it's much more versatile than your "no quality settings at all, we know best" offering). As such, given the substantial claims about the capabilities of your technology, the Snake Oil verdict shall remain.

nobodysfool 14y ago
CRF is 23 in the beamer video.
drorgill 14y ago
Again, you are missing the point. Where did the CRF number of 18.5 come from? Did you test several parameters, and found what parameter gives lower bitrates than Beamr Video on this specific clip set? Would you apply the same CRF parameter of 18.5 to any video file to reduce its bitrate? And does this parameter ensure reducing the bitrate of any video file without hurting its quality? If so, you could apply it recursively on a video clip and reduce bitrate indefinitely... The bottom line is that there is no setting of x264 that guarantees reducing the bitrate of ANY input video file while maintaining its visual quality. And this is exactly what Beamr Video guarantees.
- messel 14y ago
  The crfs are based on perceptual quality from the docs: 18 is visually lossless http://ffmpeg.org/trac/ffmpeg/wiki/x264EncodingGuide#crf http://ffmpeg.org/trac/ffmpeg/wiki/x264EncodingGuide#crf
- Daiz 14y ago
  >Did you test several parameters Nope. I just picked a value and tested what I'll get with it. Also, it doesn't matter where the number comes from. As long as I'm not changing it for different videos, the bitrate selection is completely up to x264's CRF mode. And what do you know, here it produced smaller results than your technology while providing the same level of quality! >Would you apply the same CRF parameter of 18.5 to any video file to reduce its bitrate? That's what I did for all the test videos here, and it produced better results compared to your technology on all of them (basically identical quality, smaller filesizes). >And does this parameter ensure reducing the bitrate of any video file without hurting its quality? If so, you could apply it recursively on a video clip and reduce bitrate indefinitely... Constant lossy re-encoding is going to degrade video quality no matter what - nothing is going to change that. Not your technology, not x264's CRF. Why are you even bringing up something as silly as this? >The bottom line is that there is no setting of x264 that guarantees reducing the bitrate of ANY input video file while maintaining its visual quality. And this is exactly what Beamr Video guarantees. I have just demonstrated that encoding with x264 --crf 18.5 is a more effective solution than your technology on all your presented test cases. You have given us absolutely nothing to actually "guarantee" your claims, which is exactly why your product is Snake Oil.

by Daiz 14y ago

nobodysfool 14y ago

CRF is 23 in the beamer video.

drorgill 14y ago

Again, you are missing the point. Where did the CRF number of 18.5 come from? Did you test several parameters, and found what parameter gives lower bitrates than Beamr Video on this specific clip set? Would you apply the same CRF parameter of 18.5 to any video file to reduce its bitrate? And does this parameter ensure reducing the bitrate of any video file without hurting its quality? If so, you could apply it recursively on a video clip and reduce bitrate indefinitely... The bottom line is that there is no setting of x264 that guarantees reducing the bitrate of ANY input video file while maintaining its visual quality. And this is exactly what Beamr Video guarantees.

messel 14y ago
The crfs are based on perceptual quality from the docs: 18 is visually lossless http://ffmpeg.org/trac/ffmpeg/wiki/x264EncodingGuide#crf http://ffmpeg.org/trac/ffmpeg/wiki/x264EncodingGuide#crf
Daiz 14y ago
>Did you test several parameters Nope. I just picked a value and tested what I'll get with it. Also, it doesn't matter where the number comes from. As long as I'm not changing it for different videos, the bitrate selection is completely up to x264's CRF mode. And what do you know, here it produced smaller results than your technology while providing the same level of quality! >Would you apply the same CRF parameter of 18.5 to any video file to reduce its bitrate? That's what I did for all the test videos here, and it produced better results compared to your technology on all of them (basically identical quality, smaller filesizes). >And does this parameter ensure reducing the bitrate of any video file without hurting its quality? If so, you could apply it recursively on a video clip and reduce bitrate indefinitely... Constant lossy re-encoding is going to degrade video quality no matter what - nothing is going to change that. Not your technology, not x264's CRF. Why are you even bringing up something as silly as this? >The bottom line is that there is no setting of x264 that guarantees reducing the bitrate of ANY input video file while maintaining its visual quality. And this is exactly what Beamr Video guarantees. I have just demonstrated that encoding with x264 --crf 18.5 is a more effective solution than your technology on all your presented test cases. You have given us absolutely nothing to actually "guarantee" your claims, which is exactly why your product is Snake Oil.