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Apple's Lightning-to-HDMI Dongle Secretly Packed With ARM, Airplay
New submitter joelville writes "After noticing artifacts and a 1600 × 900 image in the output from Apple's new Lightning Digital AV Adapter, the Panic Blog sawed it open and found an ARM chip inside. They suspect that video bypasses the cable entirely and instead uses Airplay to stream three inches to make up for the Lightning connector's shortcomings."
It's like having a 300HP engine in your fancy new sportscar, but all it does is turn an electric generator that delivers 50HP to the electric drive motor.
Yet, they sell it to you as a 300HP sports car.
Doubtful. More likely that it's streaming encoded digital video via the cable itself, and the components on the connector just decode the stream.
Perhaps this is a slight step forward, as far as technology is concerned, but it's a big leap back, as far as consumers are concerned...
My sig can beat up your sig.
How about a NasCar fan analogy? You think they have brains, but when you open up their skulls you find tiny Leprechauns jacking off to chrome hubcap advertisements.
The world's burning. Moped Jesus spotted on I50. Details at 11.
Thing is, MHL sends uncompressed 1080p over a cheap, standardized cable. Apple's standard, evidently, does not. And like you said, it's worse than the old docking cable in this regard. Regression is extra silly.
Looking at most MHL cable prices from vendors, they're cheaper than Apple's adaptor, but not cheap.
And as I mentioned, MHL drives up device prices because it requires additional circuitry in the device. Standardized cable you say? Try plugging an MHL cable into a Nexus 7. Won't work? That's because the chips required for MHL were too expensive and they were left off the Nexus 7.
Shifting half the expense to the device and half the expense to the cable isn't cheaper, it's just moving costs.
Really, needing a computerized cable is just silly.
Actually, it's a step forward and it's not the first technology to do this. The basic idea is, make the port a smart interconnect and let a smarter cable be more adaptive. That way a 4 meter cable can be tuned differently than a 2 meter cable and you can use the same port for a cheap copper cable or a long but expensive fiber cable. Regardless of how relatively expensive the cables are, replacing the computer is harder and adding new ports to mobile devices, even most laptops, simply doesn't happen. This makes a nice, future-proofed port for your laptop, phone, peripheral, etc. that will have real longevity.
I think we are missing the point a little here, They released a tiny computer for 50 bucks, now we just need a port of cyanogen for it.
Airplay is a network streaming technology. The network can be wired or wireless.
It's like a car company offering a stabilized phonograph in your car, for your ultra-high fidelity analog listening pleasure, and then not being able to make the interface between the phonograph and the stereo work and bailing and having the phonograph input through an FM band transmitter that plays through the radio.
No, it's like 10,000 spoons when all you need is a knife.
http://www.rootstrikers.org/
Wow, not only did you not read the article, you didn't even look at the pictures, did you?
Stop the presses! The are scaling 1024x768 content to 1600x900,
The cable is advertised as doing "up to 1080". It does not.
and there are MPEG artifacts happening as a result?!?! The deuce you say! There's never artifacts when you scale things! Never, I say!
Did you look at the picture? Those are not scaling artifacts: there is noise around edges. Those look like artifacts from MPEG or a similar compression algorithm. If it was just scaling, it would introduce aliasing patterns, which is not what they are talking about.
Next thing I know, you'll be claiming that Apple didn't replace all the already transcoded content on the Inktomi CDN with new, higher resolution content over night!
What does that have to do with this discussion?
It's almost already too scandalous that they used a CPU and software to avoid having to design and spin silicon for a Lightning-to-HDMI converter ASIC.
In fact, it looks like they did create an ARM-based ASIC, which on the face of it is bizarre to find in something sold as "an adapter cable". It's obviously doing something much more than or quite different from your standard adapter cable.
I can only echo some of the sentiments expressed in the bad ratings they received in several reviews from owners of Samsung Televisions which improperly negotiate EDID information by failing to negotiate on input sources which are not selected at the time the device comes online. One would almost think this might be an issue for Linux systems when trying to use HDMI to output to Samsung equipment, or that Dish Network DVRs might have similar problems (with the fix being to plug the device into the input channel which is selected by default when the television is powered on).
EDID? Linux? What? The article doesn't mention those topics at all. It's talking about an ARM-based chip that was unexpectedly found in a new model of a supposed "adapter cable" from Apple that is providing results that are substantially inferior to what was available on older models of Apple's similar products. As a result, if you use this cable to attach your iWhatever to a TV, you get laggy, downsampled, artifact-laden video, where Apples previous products and products from their competitors deliver sharp, un-transcoded 1080p video.
No, it's like 10,000 spoons when all you need is a knife.
Don't be silly. There is no spoon.
It must have been something you assimilated. . . .
The electronics involved have nothing to do with AirPlay, and this is not "news" in any way. Sorry to ruin excitement and conspiracy theories... :-)
I am willing to bet serious money that all these chips do is decode whatever proprietary protocol Apple uses for transmitting video over the Lightning port to a standard HDCP protected HDMI signal. This is needed because the Lightning port has no other way of transmitting the video - and this has been clear from the day Apple revealed the Lightning port to the world. It is really just a high-speed 8-pin serial connector. Nothing else.
In addition the chips probably try to introduce a classic vendor lock-in factor, making it hard for 3rd party vendors to provide similar cables and accessories for the Lightning port without paying royalties to Apple (read: legal tech-extortion).
Also, the scaling-problems mentioned are without a doubt due to the screen-mirror scheme involved. If they streamed an actual 1080p video file directly, the result would likely be very different.
The speculation in the article is so far from reality it almost hurts... They get points for taking it apart and all, but they could have reached the correct conclusion merely by reading up on the existing specs of the Lightning port (if they had bothered to add a bit of digital-video knowledge from Wikipedia that is).
- Jesper
My security clearance is so high I have to kill myself if I remember I have it...
This is a silly analogy these days. There are modern automatic transmissions that are basically just automated clutch-equipped gearboxes rather than the standard torque-converter-automatic that saps power like crazy.
Those transmissions transmit no less power to the wheels than a manual transmission would. Not only that, but they can shift faster than 95% of people can shift a manual transmission, so unless you're a freaking NASCAR driver you're going to get better performance using one of these than on a standard manual tranny.
Also they often have paddle shifters or similar so if you want to shift manually you still can.
Airplay is not involved in the operation of this adapter.
It is true that the kernel the adapter SoC boots is based off of XNU, but that's where the similarities between iOS and the adapter firmware end. The firmware environment doesn't even run launchd. There's no shell in the image, there's no utilities (analogous to what we used to call the "BSD Subsystem" in Mac OS X). It boots straight into a daemon designed to accept incoming data from the host device, decode that data stream, and output it through the A/V connectors. There's a set of kernel modules that handle the low level data transfer and HDMI output, but that's about it. I wish I could offer more details then this but I'm posting as AC for a damned good reason.
The reason why this adapter exists is because Lightning is simply not capable of streaming a "raw" HDMI signal across the cable. Lightning is a serial bus. There is no clever wire multiplexing involved. Contrary to the opinions presented in this thread, we didn't do this to screw the customer. We did this to specifically shift the complexity of the "adapter" bit into the adapter itself, leaving the host hardware free of any concerns in regards to what was hanging off the other end of the Lightning cable. If you wanted to produce a Lightning adapter that offered something like a GPIB port (don't laugh, I know some guys doing exactly this) on the other end, then the only support you need to implement on the iDevice is in software- not hardware. The GPIB adapter contains all the relevant Lightning -> GPIB circuitry.
It's vastly the same thing with the HDMI adapter. Lightning doesn't have anything to do with HDMI at all. Again, it's just a high speed serial interface. Airplay uses a bunch of hardware h264 encoding technology that we've already got access to, so what happens here is that we use the same hardware to encode an output stream on the fly and fire it down the Lightning cable straight into the ARM SoC the guys at Panic discovered. Airplay itself (the network protocol) is NOT involved in this process. The encoded data is transferred as packetized data across the Lightning bus, where it is decoded by the ARM SoC and pushed out over HDMI.
This system essentially allows us to output to any device on the planet, irregardless of the endpoint bus (HDMI, DisplayPort, and any future inventions) by simply producing the relevant adapter that plugs into the Lightning port. Since the iOS device doesn't care about the hardware hanging off the other end, you don't need a new iPad or iPhone when a new A/V connector hits the market.
Certain people are aware that the quality could be better and others are working on it. For the time being, the quality was deemed to be suitably acceptable. Given the dynamic nature of the system (and the fact that the firmware is stored in RAM rather then ROM), updates **will** be made available as a part of future iOS updates. When this will happen I can't say for anonymous reasons, but these concerns haven't gone unnoticed.
The irony is that a song called "Isn't it Ironic?" is not about irony.
Betteridge's Law of song titles clearly applies there.