@caveport i think this thread should be brought back to @Vitaliy_kiselevs topic.

Which personally I think is quite interesting. All computer storage systems have bit depth. Even UTF-8. So this discussion is intrinsic of all computer storage systems, which digital video is just one of.

So when I do a compositing job with over 50 layers, are you suggesting that I really can't see all my layers and I'm only imagining them? Your knowledge of video systems needs a little refresh!

Gosh I didn't know you always do compositing on EVERY multicam shoot you do! Unlike audio which is ALWAYS composited together when using multiple microphones.

Normally I only open up Fusion for VFX work. I didn't think that was the discussion.

Also, normally I don't ALWAYS use video in compositing, sometimes mattes, or deep pixel layers. So no, all those channels are not always going to be seperate video media assets, as they are in audio land.

Also currently most compositors are not optimised for GPU acceleration (CUDA can also be slow here as well, simply using GLSL could solve speed issues). Which is a huge problem. Even simple blend operations are still carried out on the CPU, something that a shader could easily achieve, at 32bit precision, in a fraction of the time.

Even decoding of video could be shifted from CPU to GPU, something that needs to happen asap. There are a few accelerated codecs (such as HAP) however they are not lossless enough for production work, only realtime work. (Look into Touch Designer, Vuo for realtime video mixing / effects processing).

Can we please not get personal? I would love to have a great discussion about this without being questioned, I have never questioned your knowledge. I'm sure we are all professionals here, with great bodies of work. It's not helpful having a discussion in which we just throw random: "your knowledge needs a refresh" comments.

This whole discussion has got out of hand. I've greenscreened 360 VR content with up to 100 layers 4k, and was able to playback in realtime... so no need for a refresh.

I don't understand the strawmanning, considering my last comment on this super offtopic debate:

Actually, I have realised though this discussion that there is a huge problem with my logic: We need a way to quantify the quality of both audio and video capture systems. If audio is "much simpler" then we have to quantify at what "quality" is it simpler. Lets say we capture an SD video image of an orchestra, and a super high audio recording: are they both similar? No. Why? Because the audio recording will sound much more real than the video recording. I would suggest that 4k 60p is the equivalent of a good audio recording in making the viewer feel like they were there "in the room". So with that logic, and definition of similar quality then yep, video wins the complexity race.

All because I would like to use video like audio, I didn't think this was a debatable topic. Video is getting easier to work with, try to do 100 4k layers realtime on a 10 year old PC.

As was mentioned before: video is transitioning into a more robust format similar to the evolution of audio did, (16 bit -> 24 bit).

Also remember 32 bit audio is just around the corner, with AD systems that employ the use of multiple AD stages to make distortion and peeking a thing of the past. Maybe audio is the medium that is playing catch up! ;-)

@alcomposer "But 32 video channels currently can only be edited together, and viewed one at a time, unlike audio."

So when I do a compositing job with over 50 layers, are you suggesting that I really can't see all my layers and I'm only imagining them? Your knowledge of video systems needs a little refresh!

Actually, I have realised though this discussion that there is a huge problem with my logic:

We need a way to quantify the quality of both audio and video capture systems.

If audio is "much simpler" then we have to quantify at what "quality" is it simpler.

Lets say we capture an SD video image of an orchestra, and a super high audio recording: are they both similar? No. Why? Because the audio recording will sound much more real than the video recording.

I would suggest that 4k 60p is the equivalent of a good audio recording in making the viewer feel like they were there "in the room".

So with that logic, and definition of similar quality then yep, video wins the complexity race.

@alcomposer Video digitising is way more complicated because it has spatial information which audio does not have. It is also comprised of multiple channels, each of which can be different information i.e. RGB, YUV etc. which is also very different from audio. Also the different channels can be different sample rates depending upon codec choices such as 4:2:2, 4:2:0 etc.

Quote:

"Fortunately for video, a computer can always drop a frame during playback if it gets over-worked, (miss-matched frame rates- or high complexity) in playback. Audio can not do that- as one would hear a horrid crackling sound.

So in that regard it is not simpler at all. Look into software synth design, and computer audio buffers, it is quite complex.

Also remember that high quality audio interfaces can be as expensive as a RED or Blackmagic URSA camera. With very complex designs, including word clocks, low jitter PLL etc..."

These comments don't really have anything to do with digitising complexity.

I'm also surprised you are comparing 32 tracks of audio to the RGB/YUV 3 channel encoding for video. A more accurate comparison would be 32 layers of video in a timeline, i.e. 32 similar streams processed simultaneously. I have had this kind of argument with audio engineers for many years & none of them ever been able to deliver a LOGICAL argument for why they think video digitising is as easy as audio.

I don't mean to be argumentative but I think there are gaps in your knowledge of video systems engineering and technicalities. The first post here pretty much enlightens me to the general level of understanding, even from people who claim to be knowledgable!

@StudioDCCreative

Thanks for good post, but I have strong suggestion to move it to separate topic. May be leave directly related part.

You see, bits are always powers of two (e.g. 1 bit = 6 dB in these cases).

This is wrong, for example.

Ok a 'bit' (e.g. a 1/0 binary digital element) has whatever meaning you want to interpret it as, but when they are used in base-2 mathematics which I assume since you are discussing the concept of single-bit (as compared to multi-bit) word values, this is what I am speaking of - but at this point you can omit bits and just deal with numbers themselves and the number of divisions / distinctions between the upper and lower bound they provide.

However, speaking of single-bit word values, I'm curious as to what your core argument is. It reminds me "a bit" (pun intended) of the whole 1-bit DSD encoding method right now, where the bitstream is the important part and the single bit less so, but I don't think that's where you're going with it.

I'll get to whole picture step by step.

Looking forward to it!

@alcomposer Audio digitising is way simpler than video. The processes are not comparable at all, really.

Digitization of light intensity is slowly working its way through similar issues as digital audio technology did decades ago. The 8-bit SoundBlaster standard ruled PC audio for years, much as 8-bit H.264 video does now. Audio digitization was eventually perfected with 24-bit capture and 16-bit playback, but 24-bit recording would require excessive storage sizes for video. The fundamental problem is that both audio and video work on logarithmic (db) rather than linear scales, and are most efficiently encoded in floating point rather than fixed-point formats. Camera sensors are digitally-sampled analog devices that currently produce 12 or 14-bit linear output, but this RAW RGB data is sensor-specific and unsuitable for direct viewing. Ideally, it should be gamma-corrected into an industry-standard flat log scale, with each color channel encoded in a 16-bit floating point format, with a 4-bit exponent and 12-bit mantissa. That would provide a 96db dynamic range with a consistent 12-bit color resolution at all levels of light intensity, from shadows to highlights.

For practical purposes, color resolution could be truncated down to 8-bits, with the 4-bit DR data packed into a separate 8-bit stream. Since DR varies at a far slower rate than color variations, simple delta-compression would reduce the DR stream to a small fraction of the size of the 8-bit color data, which could be compressed losslessly by about 50%. So it would require about 7-bits per native R, G or B sensor pixel to encode the entire sensor output with 96db DR and 8-bit color resolution.

@endotoxic

This not bad humor topic :-)

I think you mean steps not stops.

LOL

Ah, ok. This will be fun then!

Looks like it will not only be maths, but also computer science a bit. :-)

@Vitaliy_kiselev problem is all perception of images is "human perception". In nature there are extended ranges of colour such as IR range (birds etc) which do not exist in video range. Video colour range is specifically designed for human image perception system only.

Same issue is with sound, human hearing is only capable of 20khz (most only hear 16 if lucky, and young), however ultra sound exists in nature.

So all discussions regarding video encoding has to be based on human perception. This is actually how MP3 was developed, looking at human hearing system.

Even our scientific capture systems have to translate different ranges to visable human range. (Such as IR camera)