Multimedia, AV Archive
Given its appearance in one form or another in all but the cheapest audio gear produced in the last 70 years or so, you'd be forgiven for thinking that the ubiquitous VU meter is just one of those electronic add-ons that's more a result of marketing than engineering. After all, the seemingly arbitrary scale and the vague "volume units" label makes it seem like something a manufacturer would slap on a device just to make it look good. And while that no doubt happens, it turns out that the concept of a VU meter and its execution has some serious engineering behind that belies the really simple question it seeks to answer: how loud is this audio signal?
I love analog VU meters, and I'm kind of sad regular, non-professional music equipment has done away with them entirely.
In a previous blogpost we talked about the Opus codec, which offers very low bitrates. Another codec seeking to achieve even lower bitrates is Codec 2.
Codec 2 is designed for use with speech only, and although the bitrates are impressive the results aren’t as clear as Opus, as you can hear in the following audio examples. However, there is some interesting work being done with Codec 2 in combination with neural network (WaveNets) that is yielding great results.
I designed and built a Canon EF Mount for my Game Boy Camera. The GBC has a sensor size of about 3.6mmÂ² which seems equivalent to a 1/4" sensor. This gives the GBC a crop factor of about 10.81. With my 70-200 f4 mounted on a 1.4x extender, this gives me a max equivalent focal distance of about 200x1.4x10.81=3,026.8mm.
I always wanted a Game Boy Camera when I was a kid. It still looks like magic to me today.
FFmpeg is the leading multimedia framework, able to decode, encode, transcode, mux, demux, stream, filter and play pretty much anything that humans and machines have created. It supports the most obscure ancient formats up to the cutting edge. No matter if they were designed by some standards committee, the community or a corporation. It is also highly portable: FFmpeg compiles, runs, and passes our testing infrastructure FATE across Linux, Mac OS X, Microsoft Windows, the BSDs, Solaris, etc. under a wide variety of build environments, machine architectures, and configurations.
64kB intros, 64k for short, are like demos but with an added arbitrary limitation on the size: they must fit entirely within a single binary file of no more than 65536 bytes. No extra assets, no network, no extra libraries: the usual rule is that it should run on a freshly installed Windows PC with up to date drivers.
This is crazy.
Apple joining the Alliance for Open Media is a really big deal. Now all the most powerful tech companies - Google, Microsoft, Apple, Mozilla, Facebook, Amazon, Intel, AMD, ARM, Nvidia - plus content providers like Netflix and Hulu are on board. I guess there's still no guarantee Apple products will support AV1, but it would seem pointless for Apple to join AOM if they're not going to use it: apparently AOM membership obliges Apple to provide a royalty-free license to any "essential patents" it holds for AV1 usage.
It seems that the only thing that can stop AOM and AV1 eclipsing patent-encumbered codecs like HEVC is patent-infringement lawsuits (probably from HEVC-associated entities).
I can barely believe this is still a thing, and that it seems like a positive outcome.
Nilay Patel on the further disappearance of the headphone jack, and its replacement, Bluetooth:
To improve Bluetooth, platform vendors like Apple and Google are riffing on top of it, and that means they’re building custom solutions. And building custom solutions means they’re taking the opportunity to prioritize their own products, because that is a fair and rational thing for platform vendors to do.
Unfortunately, what is fair and rational for platform vendors isn’t always great for markets, competition, or consumers. And at the end of this road, we will have taken a simple, universal thing that enabled a vibrant market with tons of options for every consumer, and turned it into yet another limited market defined by ecosystem lock-in.
This is exactly what's happening, and it is turning something simple and straightforward - get headphones, plug it in literally every single piece of headphones-enabled audio equipment made in the last 100 years, and have it work - into an incompatibility nightmare. And this incompatibility nightmare is growing and getting worse, moving beyond just non-standard Bluetooth; you can't use Apple Music with speakers from Google or Amazon, and Spotify doesn't work on the Apple Watch.
Removing the headphone jack was a user-hostile move when Apple did it, and it's still a user-hostile move when Google does it.
About four years ago, we shared our plans for playing premium video in HTML5, replacing Silverlight and eliminating the extra step of installing and updating browser plug-ins. Â
Since then, we have launched HTML5 video on Chrome OS, Chrome, Internet Explorer, Safari, Opera, Firefox, and Edge on all supported operating systems. Â And though we do not officially support Linux, Chrome playback has worked on that platform since late 2014. Â Starting today, users of Firefox can also enjoy Netflix on Linux.Â This marks a huge milestone for us and our partners, including Google, Microsoft, Apple, and Mozilla that helped make it possible.
It wasn't that long ago we barely dared to imagine HTML5 video taking over from Flash and Silverlight.
In this video you'll see the first machine and the last machine as well as some in-between. There's talk about MD-LP, Net-MD and HiMD. It's a personal retrospective of a format that was loved by many people around the world but one that is all too often is judged purely on its lack of performance in the US market.
I'm one of those MiniDisc people. MiniDisc was fairly successful in The Netherlands, and quite a few people around me were MiniDisc users as well. I've had countless machines over the years, and I was still using HiMD well into the smartphone era - and carried both a smartphone and my HiMD player for quite a while. Even though the world had long ago moved on to MP3 players and then smartphones, I was still using MD.
I've long wondered why, and this video finally made it dawn on me: rituals. Since prerecorded MiniDiscs were rare and incredibly expensive, you copied CDs onto MiniDiscs instead. Especially before the advent of NetMD and later HiMD, you did this without the help of a computer. You'd get a new album, listen to it, enjoy it - and then, to make sure you could listen to it on the go, you plugged one end of an optical cable into your CD player, the other end into your portable MD recorder, and copy the CD in real time. Once it was done, neat freaks like me would even enter all the track information using the little dial on the recorder, track by track, letter by letter. Painstaking doesn't even begin to describe it.
Even listening to your MiniDiscs - they were satisfying to hold, the loading and unloading was deeply mechanical, the spring-loading trays were a delight. It was just an endless array of rituals that, while pointless and cumbersome to others, were deeply enriching and soothing to me. I guess it must be similar to people still using vinyl today.
To me, MiniDisc was one of the greatest formats - not because it was better or more advanced (even though during the 90s and early 2000s, it actually was), but because it was full of little delights and rituals. Just one of those irrational things that only few of us will ever fully understand.
While common magnetic tape uses very thin, plastic-coated iron oxide, "talking rubber" uses rubber impregnated with iron oxide. Iron oxide (a form of rust) is ferromagnetic, which means in the presence of a magnetic field, the electrons in the iron oxide magnetically line up and stay that way even after the magnetic field is turned off. This allows cassette tapes to create a â€œtrackâ€ of magnetically aligned iron oxide when the electromagnet in a cassette recorder creates a magnetic field.
But with magnetic rubber, the iron oxide is actually mixed into the rubber material; the whole band becomes ferromagnetic, instead of just the coating. According to that Bell System Journal article, this â€œtalking rubberâ€ could be around 1/16 or 1/8 of an inch think, whereas magnetic tape was (even in the '50s) already much thinner at 1/1000 of an inch thick.
More obscure audio formats!
Back before all-digital music, back before the Digital Compact Cassette, back before even the Digital Audio Tape existed, there was a strange audio device that briefly captured the imagination of Hi-Fi freaks across the world. The Elcaset, as it was called, was an enlarged cassette that started in Japan, wove its hidden, spinning spools around the world, and then finished, appropriately enough, in Finland.
As someone who swore by MiniDisc up until quite recently, I love obscure audio formats. This article is from the summer of last year, but I only came across it just now thanks to Atlas Obscura.
H.264 is a video compression codec standard. It is ubiquitous - internet video, Blu-ray, phones, security cameras, drones, everything. Everything uses H.264 now.
H.264 is a remarkable piece of technology. It is the result of 30+ years of work with one single goal: To reduce the bandwidth required for transmission of full-motion video.
Technically, it is very interesting. This post will give insight into some of the details at a high level - I hope to not bore you too much with the intricacies. Also note that many of the concepts explained here apply to video compression in general, and not just H.264.