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marcan_42
Villodre
I've tested a handful of them and they're always the same: not a single one of them are advertised in a honest way. Some have even a true USB 3.0 connector soldered, which of course the chip doesn't support.
I didn't know I had you to thank for a far better support in Linux!
bartvk
Seems like you're the Marcan of Asahi Linux fame! I'm a supporter of your work, thanks for making the world a more interesting place!
iforgotpassword
> due to a hardware bug, it advertises itself as 96kHz mono, so Windows and macOS will give you that
Wait, shouldn't that sound really broken? I guess it depends on how exactly they are interleaved, but shouldn't the pitch be twice as high for example?
richrichardsson
So the dongle will be doing something like this:
LLLL... (48kHz mono) ---
\
> LRLRLRLR... (96kHz mono)
/
RRRR... (48kHz mono) ---
Listening to it as a raw 96kHz mono stream will sound (very likely) completely awful (depending on how different the L/R signals are) as well as pitched down 1 octave.
edit: I may be confused about the direction the pitch shift is, you may well be correct that its pitch would be doubled rather than halved.
edit 2: actually the pitch would be unaffected; think about if you took a 48kHz signal (L...) and repeated every sample (LL...), if you played that at 48kHz the pitch would half, but playing it at 96kHz would double the pitch -> no pitch change. So really the issue would be how different L and R signals are that would introduce higher harmonics.
iforgotpassword
Right, that would work if it's interleaving every sample, but I think as soon as you do chunks of eg 5ms or so, there should be the mentioned doubling of pitch and other glitches. So maybe since they got away with selling this buggy thing anyways it is indeed interleaving every sample as you suggested.
marcan_42
No, it sounds perfectly fine. Mathematically, interleaving samples like this is equivalent to zero-padding every other sample to upsample, with no antialiasing filter. Then you add the other channel offset by one sample. The end result is that you have both channels summed up in the low 24kHz of spectrum, with half a 48kHz sample of offset for one channel (mostly negligible), and everything mirrored in the top 24kHz of spectrum as aliasing (which you can't hear). In other words, it will be very, very close to what a simple mono downmix would sound like.
gsich
No. Think of it as an offset. The 2nd channel begins at 48kHz.
iforgotpassword
I don't follow. We have two streams at 48khz, say 16bit. They get somehow interleaved to 96khz, so that must be 16bit as well. If they were interleaved to one at 48khz 32bit, I could see what you mean, one channel would just be very faint noise on top of the other.
sam_lowry_
What device would you recommend for HDMI capture without breaking the bank?
stephen_g
I use a Blackmagic Design Ultrastudio Recorder 3G. Requires Thunderbolt 3 but it’s pretty cheap for the quality.
_joel
Blackmagic all the way, we used them extensively (still do) at the beeb. Their linux driver support is excellent too, the only maintenance I ever needed to do as a sysadmin supporting a fleet of these was occasionally update their firmwares.
jinto36
A note on Blackmagic hardware in general (including the ATEM switches)- they tend to only work with signals that are fully compliant with broadcast standards. For example, I have some Cisco HD PTZ cameras with a "raw" HDMI output that sends 1080p30 or 1080p60, but there's some wacky difference in the colorspace they output such that my Atomos recorder and Blackmagic capture devices only lock sync when the video level (brightness) of the scene overall is low, such as when you put your hand over the camera. The same cameras work fine with the $25 generic USB capture devices, as well as with the Avermedia BU110 which should be a "true" uncompressed USB3 HDMI capture device (that recently was marked down to $60).
paulmd
I know Blackmagic is a popular brand for actual cine camera equipment, how do they compare to the more common Elgato 4K60 PCIe? Obviously thunderbolt is nice as an interface rather than the add-in card, but is there anything else it offers above and beyond that?
em3rgent0rdr
I use Blackmagic Design's "DeckLink Mini Recorder" which plugs into PCI-e.
epakai
Inogeni devices can be had secondhand pretty cheap. These are FPGA based, and supported by UVC driver (works on most platforms). Firmware update is via a windows app.
dawnerd
You might be able to get away with an elgato camlink 4k but you'd need software to actually record the input.
gsich
The device discussed in the article.
It depends on what you want to achieve. Have a better camera in Teams/Zoom? More than enough. Capture VHS too.
_joel
Definitely workable but if you want better camera in VC then you may be best going for one that supports h264 or something more modern than MJPEG over USB2. If you've already got a camera then fair enough, get a cheap dongle (or spend a few quid more and get a blackmagic decklink for 99 buck/quid/whatever - PCIe though, but could use a breakout ymmv)
gsich
See this comparison: https://screenshotcomparison.com/comparison/22713
It really depends on what version (or configuration?) of the device you get. Both have the same USB-IDs.
daneel_w
I happen to have that exact same adapter. It can provide FullHD, but only at 30 fps. At 720p it manages 60 fps fine.
marcan_42
No, really, it can't. Feed it a checkerboard input and you'll get gray on the way out. It's horizontally processed at a lower resolution internally. Might be 960x1080 at 30FPS, and it can't do it at 60FPS at all. Yes, you're going to get 1920x1080 JPEG bitstreams out the USB end, but it's not actually 1920x1080.
I suspect this happens because it doesn't actually have enough internal RAM to buffer a full 1080p frame (this chip uses on-die RAM, so probably SRAM since they wouldn't go for a fancy EDRAM process, and SRAM is expensive by capacity).
rubatuga
Agreed, likely an internal resolution of 1280x1080. You can check out the checkerboards on my blog post here, which also analyzes the chroma sub sampling and post sharpening.
https://www.naut.ca/blog/2020/07/09/cheap-hdmi-capture-card-...
daneel_w
Yes, really, it can, because a checkerboard test along with other fine detail tests and frame rate tests was what I put the device through to make sure I really received what I needed. It correctly manages exactly what I stated: 1080p at 30 fps, 720p at 60 fps. It's a let-down since the specs claimed otherwise, but that's what it can do.
gsich
I have 2 devices, one has 1280x1080, the other 1920x1080. Can't really be differentiated from the outside. The one has a silver casing, the other a black one.
zo1
Has someone done this sort of analysis" on YouTube? Anecdotal: Even though it claims it's giving me the 1080p resolution, everything still seems blurry. The only time I get actual crisp visuals is when I watch a 4k stream and "down scale" it to 1080p. I feel like they're pulling a fast one on us.
russdill
A nice side effect is you can feed to 1920x1200 and it will do the same downscaling.
bombcar
This is just "dodgy equipment may break the rules" - not the more complicated situations now common where the connector (especially USB-C) can no longer be used to indicate the capabilities of the device.
donatj
I almost bought a USB hub recently on Amazon that had blue ports but was actually USB-2. Thankfully I took the time to read the negative reviews first, followed by the fine print of the actual product description.
rkangel
This is the exact sort of situation that supports the ever increasing importance of brands.
This is obviously a cheap chinese product, and therefore there are low expectations of quality in the result. The same is still true but in a less obvious way even from more reputable channels like buying a USB charger from a shop in an airport there are so many ways that the implementation can be subtly not what you want and not give you the right charging speed with ONE of your phones. You can't read reviews of every product and even if you could, they're not going exhaustively test every last technical aspect of something.
My solution to this particular issue is that I buy all of my USB chargers from Anker (direct, not via Amazon). I know I'm getting a product from a company that has thought about it and tested it thoroughly, so my chances are much better. And the same is true with other products.
loudmax
Anker is a Chinese company incidentally. People often disparage "cheap Chinese" knock-offs, but the salient feature here is cheapness and dodgy branding, not the fact that they're made in China. Geopolitics aside, the Chinese are absolutely capable of building good stuff, as demonstrated by brands like Anker.
ziml77
It's not that China universally produces garbage. It's that they can get away with producing garbage and even straight up knockoffs. Additionally they already have the equipment there to manufacture this stuff. That leads to most of those terrible items coming from Chinese companies. That's why Chinese, cheap garbage, and false marketing are associated with China. If they don't want that to be the case, someone would need to crack down on the lies and knockoffs.
dleslie
They're also effectively out of reach of western regulatory reprisal.
If a Chinese company ships a batch of garbage electronics to western markets that lead to a string of house fires there's basically no chance that anyone will be held accountable for it; whereas, if a western company did the same they'd be far easier to hold accountable.
So Chinese producers can, and do, assemble and ship dangerously unsafe electronics in order to cut costs.
mitchdoogle
A lot of good quality stuff comes from China as well, including many luxury brands. Why do they only get the reputation for the bad stuff?
koala_man
Anker's business model is exactly identifying these quality manufacturers and doing the QC.
It's a fantastic, valuable service, and they do it really well.
jdavis703
Anker isn’t cheap though. If you’re looking for the cheapest accessory on Amazon it’s rarely going to be Anker.
The problem is people buying the absolute cheapest item, which is most likely going to be from China. If anything it’s a testament to their industrial prowess that they can crank out “good enough” equipment this cheaply.
But seriously if you actually care enough about quality to dump the USB data, maybe don’t buy the cheapest thing on Amazon. Or buy it with the assumption you’ll need to run diagnostics on it first and hope it doesn’t short out anything or catch fire.
microtonal
This is the exact sort of situation that supports the ever increasing importance of brands.
There are many brands that still profit off their good name, but by now are just selling generic Chinese designs with fancier enclosures. E.g. my wife bought a Satechi USB-C On-the-Go adapter. One of its stated features is that it supports 4k@60Hz. Except that it didn't work. We tried different 4k screen models from different manufacturers and two different MacBooks and a Windows PC. All of which work fine with a USB-C DP alt-mode cable and a Lenovo USB-C Dock [1]. We contacted their support and they recommend that we do a firmware update. They send you a completely undocumented Realtek firmware updater (Windows-only) that doesn't work.
I was surprised by all of this, because Satechi used to be a reputable brand for Mac adapters. So, I investigated the adapter a bit more and the MAC address stood out. The MAC address was registered to Part II Research, which doesn't really seem to exist anymore. However, looking at their website through archive.org showed that they were a division of the Chinese brand Power 7 Technology. After browsing their website, I found an adapter that was more or less identical to the Satechi USB-C On-the-Go. The same port layout, the same touted features, but with a different enclosure:
https://www.power7tech.com/page/305
Power 7 makes reference designs and sells them to manufactures that rebrand them. This explains why Satechi couldn't provide proper support and couldn't even provide a working firmware updater. They didn't design the device or the firmware. Needless to say, we returned the adapter.
When I was researching this, I found a nice blog post that opens up several adapters from reputed brands (Satechi, Icy Box, Anker) and finds that they are just rebranded generic designs of typically pretty miserable quality:
https://overengineer.dev/blog/2021/04/25/usb-c-hub-madness.h...
After several bad experiences with adapters and docks that do USB over USB-C, I try to buy Thunderbolt accessories when possible. You see some of the same crap (Realtek RTL8153), but on average the quality seems to be better.
[1] The 4k@60Hz support, the Lenovo Dock has other issues.
paulmd
EVGA made a line of capture devices that I suspect were made by either this brand or another similar OEM selling generic designs. They got nailed for advertising a lot of specs that were basically completely fake (the device could not do some of the modes at all, not just fake internal resolution but couldn't even output them) and then went through a couple rapid iterations of similar specs that were just fake.
https://www.youtube.com/watch?v=QsICWRnj-60
EposVox has been doing a whole series. The whole market seems to be really shady and hit-or-miss if you don't go with a name-brand like elgato or blackmagic.
Huge number of sellers are just slapping their brand on an OEM design and the OEM doesn't seem to mind lying about what their design will do, and then the OEM is caught in the middle of angry customers and an OEM who just flagrantly doesn't care.
mschuster91
I'd be interested in what is inside the hood of my Belkin USB-C adapter (https://www.amazon.de/gp/product/B08X5168HM/). It works flawlessly, with the only downside being that it forcibly removes 15 watts from the Power Delivery budget which is enough for my s/o's Acer Switch X notebook but not for my 2019 16-inch MBP.
Gigachad
The value of Apple products when it comes to dongles and cables is pretty clear to me. While most people laugh at that $100 usb C hub thing, I haven’t been able to find a single alternative that is as good and significantly cheaper. Most products with the same ports cost almost as much and were constant sources of issues when we used them at work while the Apple one just always works in every case.
I got one of the basic usb 3.0 A to C cables on eBay and while it generally works, I was only able to get 300mbps over it while the apple one did the full gbit I was testing.
These specs are never written anywhere. You only know when you test it out. And I find the Apple one just passes all tests while 3rd party brands are a roll of the dice.
goosedragons
The specs are often buried in the description on places like Amazon where you get this junk. I don't think the Apple ones are trouble free either. They don't even list what wattage the USB C power port on their dongles takes on the store page [0]. Just a completely separate support page for some reason [1].
[0] https://www.apple.com/shop/product/MJ1L2AM/A/usb-c-vga-multi...
Gigachad
My guess is as part of the Apple "Just works" philosophy, they just make sure the wattage is high enough to power everything they list on the compatible section and then they can exclude the spec since the user need not ever worry about it.
radicality
Have you had any knockoffs of Anker when purchasing via Amazon?
I ask as I do a bunch of my shopping on Amazon (trying to cut down because of the fakes/inventory commingling) and recently bought some Anker stuff - as far as I can tell it looks legit.
I usually make sure the product is sold by Amazon, or some trusted brand (here, sold by AnkerDirect and shipped by Amazon). Have you had bad experiences and hence recommend always ordering direct from manufacturer?
rkangel
I think I've been relatively lucky - I've had one cheap product that wasn't quite what it should have been, but nothing from Anker. My policy is to avoid ordering from Amazon if at all possible. This is both because of the risk of counterfeits, but also for the 'vote with your wallet' approach that I don't agree with a lot of what they do.
StillBored
Happens all the time with keyboards, which are overwhelmingly running at USB1 low speed (1.5Mbit) despite many of them advertising USB2 or even USB3 sometimes. I even found one that was actually USB3 for the built in hub and lighting device, but the actual keyboard was still low speed.
And IIRC it turns out to be legit as the newer specs all say something to the effect that they are fully backwards compatible with the previous version of the spec, as well as any new requirements.
So, yes USB 3.1 "high speed" (aka 480 Mbit) is legal spec wise.
PS: If anyone knows of an actual keyboard that runs at high speed or better, i'm still interested since I have a couple devices that might be nice if they hard keyboards but don't support USB1 low/full speed.
em3rgent0rdr
I'm sorry but serious question, why would you need a high-speed for a keyboard? A usb packet for a keystroke is roughly 180 bits (I'm estimating from glancing at https://youtu.be/wdgULBpRoXk?t=1390). So 1.5 Mbit/s low speed could roughtly handle over 8,000 keystrokes per second. Do you really need more keystrokes or finer resolution than that?
StillBored
"I have a couple devices that might be nice if they had keyboards but don't support USB1 low/full speed. "
Its not about the keyboard, its about the host not supporting USB1 speeds or TTs.
fomine3
Same story goes for HDMI 2.1 https://tftcentral.co.uk/articles/when-hdmi-2-1-isnt-hdmi-2-...
opan
There may be enthusiast mechanical keyboards that use faster ports. My keyboard uses an Elite-C MCU in each half. I've heard some more modern stuff is switching to ARM for the MCUs.
Here's a keyboard that uses an ARM MCU:
megous
"I bought some dongles on eBay after zero research, and they don't have specs I dreamed up". lol
Even if you bought USB 3.0 ones, to get raw YUV or RGB data, you specifically have to buy ones that support that. (and your desired frame rate, because you can easily buy dongles that only support 60FPS and not 50FPS your camera may output)
Don't buy from Chinese vendors that don't provide detailed specs.
michaelt
> Don't buy from Chinese vendors that don't provide detailed specs.
Better yet: You can get a free HDMI-to-USB2 converter, by just ordering a cheap ebay HDMI-to-USB3 converter then requesting a refund when what turns up is inevitably USB2.
oynqr
That works great until the seller wants you to ship it back and PayPal finds this acceptable.
smilespray
Good advice.
Also, some Chinese sellers will flat-out lie in the specs, so when you're a cheapskate like me, buy from a marketplace that offers hassle-free refunds.
eBay is better at this than AliExpress, for instance. Avoid Wish like the plague. (Amazon is not locally available in my area, so I have no opionion about them.)
daneel_w
"Also, some Chinese sellers will flat-out lie in the specs, so when you're a cheapskate like me, buy from a marketplace that offers hassle-free refunds."
This is the takeaway. Some lie about it knowingly, and some just don't know any better as they are just reselling devices they bought in bulk from the manufacturer who lied about the specs.
This mode of operation is systematic with cheap Chinese products and the sales of such, because every time one of those few alert customers bother themselves with raising the issue, the seller instantly negotiates a discount - now they still made a buck and you still accepted to pay for a faulty product, because it's less hassle than returning it, and shipping it back often costs more than the device itself.
Whenever I pick up some cheap Chinese trinket I understand it will be a gamble.
megous
I try to buy from the manufacturer operated merchant accounts on Aliexpress, when buying anything more expensive or specialized. Sometimes it's not the cheapest option, but I tend to trust them more.
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russdill
It's listed on Amazon with the same specs.
megous
The article doesn't provide any links. Anyway, reseller provided specs are not that great source either. I meant vendor as in manufacturer. (I'm not a native speaker and for some reason I have some assication between vendor = manufacturer, probably due to my programming background. I'll have to work on that. :D)
0des
What's going on with the subject object verb agreement in the title? I see this format sometimes and it confuses me. Is the purpose of this format to convey something?
stirfish
That format is called "hyperbaton". As with most weird things in English, blame poetry.
https://en.wikipedia.org/wiki/Hyperbaton
https://english.stackexchange.com/questions/25508/is-employi...
https://english.stackexchange.com/questions/27420/why-is-xxx...
rootusrootus
As is so often the case on HN, the real value is in the comments. Thanks for teaching me a new thing today. Anastrophe is going to be my word o' the day, I think.
mohn
And here in the "Forest of Rhetoric" [0], anastrophe is just one of the 433 rhetorical figures currently cataloged, many of them with fun Greek names. You've got well over a year of word o' the day material. Epistrophe is another good one.
neogodless
https://english.stackexchange.com/questions/52596/proper-usa...
Lots of discussion around the phrase origin there.
Possible "original":
> the archetypal phrase is "One swallow does not summer make".
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johnwalkr
It’s older English, like Shakespeare which has stuck around for emphasis. It emphasizes “blue connector” in this case.
baochan
I know it from "Stone walls do not a prison make": https://en.m.wikipedia.org/wiki/To_Althea,_from_Prison
I find when colloquialisms like this are used it's to make a point, like using a child's nursery rhyme to indicate "something so obvious a child would know it". I think in this case it's meant to imply "This is such an obvious statement that it would be known even in antiquity, but..." to allay a "duh, no kidding" response and make the headline more eye-catching.
gizmo686
The agreement is normal, and occurs between "does" and "connector". The weird thing is the word order.
A typical order would be "A blue connector does not make USB 3.0"
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grishka
By Yoda was, this title clearly written
gigaflop
And even if it was a 3.0 connector, a cheap manufacturer could have just not connected the extra pins on the port.
politelemon
Author skipped a bit, didn't indicate which part of the lsusb output made it obvious it's USB 2.0.
My knowledge is limited, I think it might be the 480M indicating the speed.
For USB 3.0 you'd see a higher number... 5000? I'm glancing at this page https://en.wikipedia.org/wiki/USB_3.0
adrian_b
Yes.
The easiest to see the speeds is with "lsusb -t", which will list all ports and connected devices, with their speeds and the kernel drivers that are used by them.
For USB 2.0 high speed you will see "480M", for standard speed you will see "12M" and for low speed (e.g. keyboards and mice) you will see "1.5M".
For USB 3, you will see "5000M" (USB 3.2 Gen 1x1) or "10000M" (USB 3.2 Gen 1x2 on Type C connector).
Besides checking the speed, for some devices it is useful to check the kernel driver that is used, to verify if their full performance is reached.
For example, in the case of an external SSD or USB memory stick which claims to support UAS (USB-attached SCSI), "lsusb -t" should display "Driver=uas". If it displays "Driver=storage", that means that due to some quirk the device capabilities have not been recognized and the kernel uses the much slower Bulk-Only transport protocol, instead of UAS.
mistrial9
I notice this forum post: https://github.com/mvp/uhubctl/issues/12
db48x
That or 10000M, or if you don’t use the -t option you will see this:
Bus 005 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hubkevin_thibedeau
> For USB 3.0 you'd see a higher number
Not necessarily. For alt mode applications you'll be stuck with the 480MB/s data pins because the USB3 lines are repurposed.
yrro
Is it permitted by the spec to use a blue connector for USB 2?
(Not that it matters, since there's no USB logo on the device, at least on the side we see photographed).
daneel_w
Specs mean nothing to Chinese developers of one-off products.
jrockway
It's not just China or one-off products. Nintendo couldn't figure out the USB Type C spec for the Switch. I guess the ultimate spec is the "does it work on my machine" test, and the Chinese HDMI dongles and Nintendo Switch both passed with flying colors. Ship it!
daneel_w
That's technically correct. Nintendo goofed up, but with China it's an established system.
noasaservice
I ran across this issue with a Toshiba HDMI->USB dongle for $20 bought from Walmart.
They did the scammy blue adapter, but none of the usb3 pins.
Espressosaurus
PNY makes a bunch of USB 2.0 flash drives with blue connector. I bought a couple thinking I got a decent deal and then realized my mistake when I saw the copy speeds.
Infuriating.
BizarroLand
I wonder why anyone would ever sell more than a 16gb flash drive with usb 2.0 speeds. Unless the flash media is so internally slow that it can't transfer faster than 30mb or so there's no reason for it. No one wants to sit around and wait 25 minutes to copy a file over.
toast0
Heat. Small usb drives can barely disipate any, and fast data transmission will generate a lot.
I'd rather buy a 2.0 device that won't get hot enough to be uncomfortable.
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> I can get 1920x1080 at 60fps from it.
No, you can't. It's not just MJPEG, it's internally downsampled to less than 1920 pixels of effective horizontal resolution, even though it technically spits out 1920 pixels via USB. It'll do true 1280x720 though (still with MJPEG). You're also going to get stereo audio on Linux with recent kernels only because I sent in a patch to make that work - due to a hardware bug, it advertises itself as 96kHz mono, so Windows and macOS will give you that (which is actually 48kHz stereo with both channels interleaved, but they couldn't advertise it as such because it does not correctly handle packet boundaries in a way that'd be spec-compliant for stereo audio).
Welcome to the wonderful world of Chinese HDMI capture cards. These particular little dongles are all using MacroSilicon MS2109 chips. Cheap and okay-ish for some use cases, but don't expect a high quality capture card or raw uncompressed video at this price point.