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I'm no expert when it comes to video codecs but I'm surprised that we're still able to see such strong claims of algorithmic improvements to h264, and now to h2

I'm no expert when it comes to video codecs but I'm surprised that we're still able to see such strong claims of algorithmic improvements to h264, and now to h265. I'm also aware of how patent-encumbered this whole field is and I'm skeptical that this is just a money grab. This is really just a press release, what's actually new? Can it be implemented efficiently in hardware?

bob1029 6y ago
Your skepticism is very healthy, especially in this arena. With video codecs, information theory is ultimately the devil you must answer to at the end of the day. No amount of patents, specifications or algorithmic fantasy can get you away from fundamental constraints. It seems like the major trade-off being taken right now is along lines of using more memory to buffer additional frames. This can help you in certain scenarios, but in the general case, you cannot ever hope that a prior frame of video has any bearing on future frames of video. It is just exceedingly likely that most frames of video look much like prior frames. So, you can certainly play this game to a point, but you will quickly find yourself on the other end of the bell curve. You can also play games with ML, but I argue that you are going even further from the fundamental "truth" of your source data with this kind of technique, even if it appears to be a better aesthetic result in isolation of any other concern. There are also lots of one-off edge cases that have always been impossible to address with any interframe video compression scheme. Just look at the slowmo guys on youtube dump confetti on a 4K camera. No algorithm except for the dumbest intraframe techniques (i.e. JPEG) can faithfully reproduce scenes with information this dense, and usually at the expense of dramatic bandwidth increases. Bandwidth is cheap and ubiquitous. I say we just use the algorithms that are the fastest and most efficient for our devices. We aren't in 2010 sucking 3G or edge through a straw anymore. Most people can get 20+mbps in their smartphones in decently-populated areas.
- freeone3000 6y ago
  The advantage of the H-series of codecs is strong support of hardware implementation. This has been a selling point since H.262. You can get a H.265 IP core from Xilinx, Intel, and other major vendors -- so the actual runtime performance for H.266 (once a core is available) will be very low and constant (and comparable to current codecs). Bandwidth and storage space are real costs, despite the handwaving around it, and reducing these requirements while not reducing visual quality is an important step. As for "information-dense scenes": Pathologic cases such as the HBO intro screen are encoded into modern codecs as noise, and regenerated client-side, because there's no actual information there. These scenes are either engineered or pure noise.

bob1029 6y ago

Your skepticism is very healthy, especially in this arena. With video codecs, information theory is ultimately the devil you must answer to at the end of the day. No amount of patents, specifications or algorithmic fantasy can get you away from fundamental constraints. It seems like the major trade-off being taken right now is along lines of using more memory to buffer additional frames. This can help you in certain scenarios, but in the general case, you cannot ever hope that a prior frame of video has any bearing on future frames of video. It is just exceedingly likely that most frames of video look much like prior frames. So, you can certainly play this game to a point, but you will quickly find yourself on the other end of the bell curve. You can also play games with ML, but I argue that you are going even further from the fundamental "truth" of your source data with this kind of technique, even if it appears to be a better aesthetic result in isolation of any other concern. There are also lots of one-off edge cases that have always been impossible to address with any interframe video compression scheme. Just look at the slowmo guys on youtube dump confetti on a 4K camera. No algorithm except for the dumbest intraframe techniques (i.e. JPEG) can faithfully reproduce scenes with information this dense, and usually at the expense of dramatic bandwidth increases. Bandwidth is cheap and ubiquitous. I say we just use the algorithms that are the fastest and most efficient for our devices. We aren't in 2010 sucking 3G or edge through a straw anymore. Most people can get 20+mbps in their smartphones in decently-populated areas.

freeone3000 6y ago
The advantage of the H-series of codecs is strong support of hardware implementation. This has been a selling point since H.262. You can get a H.265 IP core from Xilinx, Intel, and other major vendors -- so the actual runtime performance for H.266 (once a core is available) will be very low and constant (and comparable to current codecs). Bandwidth and storage space are real costs, despite the handwaving around it, and reducing these requirements while not reducing visual quality is an important step. As for "information-dense scenes": Pathologic cases such as the HBO intro screen are encoded into modern codecs as noise, and regenerated client-side, because there's no actual information there. These scenes are either engineered or pure noise.