A few words from a post-production person who has been working with digital video and audio for almost 20 years.
First, something of a disclaimer. I'm not an investor; I own no stock what-so-ever. Yours is a world I know next to nothing about, which is why I will not give you my opinions on investing. I do, however, know quite a lot about digital video formats, containers, bitrates, distribution and playout hardware, and that's what I'm here to talk about.
I own more than two dozen external media players, i.e. little boxes like the Nuvola NP-1. Testing media players is directly related to my work, but it's also a hobby of mine. So it was with great interest that I placed an order for the NP-1 back in Autumn of 2013. I had to wait for delivery for a year, give or take some weeks. And when it arrived, it was completely useless. By installing third party player apps I got it to play most HD video files from a USB stick rather well - but trying to play anything available on UltraFlix was an exercise in frustration. In short, none of the free clips on UF played smoothly. Even worse, most clips also suffered from heavy blocknoise, where the image turns into large "blocks".
I assumed these playback issues were caused by my internet connection which at the time could reach 13 megabits/sec on a good day. I knew 13mbps was nowhere near enough for proper 4K delivery so I put the NP-1 aside to wait for a speedier internet connection.
Let's talk about a bit megabits and codecs because they are supremely important when discussing any digital video delivery over the internet.
You may have read about this new video codec called HEVC, also known as H.265. It's the latest and currently most efficient method of compressing video. One could say it's a fourth generation codec, first one being MPEG-1, followed by MPEG-2, then AVC (aka H.264) being 3rd generation. Each generation has so far been approximately 50% more efficient than the previous one.
What does that mean? In short, it means each new generation needs only half of the bitrate (i.e. megabits per second) of the previous generation's to realize the same picture quality.
Let me give you an example of what this means in reality. (We can omit MPEG-1 at this point as it's completely obsolete.) MPEG-2 codec is still widely used in HDTV broadcasting in the USA, although broadcasters are rapidly moving to AVC and even HEVC.
A rather typical HDTV broadcasting bitrate for MPEG-2 video is 20 megabits per second. If that same video was compressed using AVC, we could have the same picture quality with only 10 megabits per
second. Using HEVC, same picture quality could be achieved with only 5 megabits per second.
You'll note I mentioned HDTV, i.e. HD, which is made of 1920 x 1080 pixels for a total of ~2 million pixels. 4K (or Ultra HDTV as it should be called) picture is made of 3840 x 2160 pixels, or roughly 8 million pixels. It's easy to think that since there are 4 times as many pixels in the image, 4K would need 4 times the bitrate of HD, right?
Unfortunately it's a very complex issue so to keep it simple for discussion's sake, let's just say the bitrate multiplier hovers between 2x and 3x when resolution increases 4x.
As for what kind of bitrates are usually needed for 4K delivery, let's take a look at Netflix. They encode their content in HEVC at a bitrate of 16.2 mbps. I can tell you that does not give them anything even remotely close to "visually lossless" image quality.
There's a codec called CineForm which is actually owned by GoPro these days. CineForm compressor has an option for "visually lossless" which truly is what it says on the tin. The bitrates it uses vary a lot based on the content being compressed, but I've never seen it go below 300 megabits per second for 4K video. I've seen it go way above 1000 mbps when compressing high-motion, high-detail 4K at 60fps.
Let me be clear: "visually lossless at 4mbps" 4K cannot be achieved with current codecs.
And no, NanoTech does not have some proprietary magic codec that achieves the impossible. The reason for that is quite simple: they have to use the codecs supported by playout devices, in this case Nuvola NP-1 and 4K televisions. That means either AVC or HEVC.
I recently dug out the NP-1 to do more testing. My new connection can do 80mbps so it wouldn't be the culprit if NP-1 misbehaved again. The experience was no better than previously. UF content was utterly unwatchable. I installed an app which shows bandwidth usage on screen: it reached above 25mbps quite often, and even that wasn't enough to achieve proper playback.
Here's the kicker: NP-1 is based on an Nvidia Tegra 4 chip, which does not support HEVC in hardware.
That means it would need a special software add-on in order to understand HEVC video streams. NanoTech made some noise a while back that they had licensed such software from an Indian company, but I have seen no evidence of that software ever making it to NP-1.
What's more, that software add-on would not solve the biggest problem: Tegra 4 is woefully underpowered to decode HEVC video streams. In other words: even with that software, NP-1 could not play 4K HEVC-encoded video streams from UltraFlix.
And that means UF must be streaming AVC-encoded video to the NP-1. Remember what I wrote about codec generations earlier? To achieve relatively good (i.e. nowhere near visually lossless) image quality in 4K, you need something like 35-50 megabits per second when video is encoded in AVC. Which coincides nicely with the bitrates I saw reported on the screen during my NP-1 testing.
So why didn't UF content play properly if my connection can do 80mbps? The likeliest explanation is that while my internet connection can do 80mbps between my home and my ISP, UltraFlix can't serve data to my ISP fast enough, resulting is glitchy playback.
Okay, that went on for much longer than I intended, sorry 'bout that. I hope the above helped you understand the underlying technical issues a bit better.
