avidiax (u/avidiax) - Readit News

avidiax commented on Fix HDMI-CEC weirdness with a Raspberry Pi and a $7 cable johnlian.net/posts/hdmi-c... · Posted by u/jlian

rgovostes · 6 hours ago

This is the lord’s work. It’s ridiculous that in 2025 my $500 gaming PC GPU cannot tell the receiver to change inputs. Even my Apple TV, which is considered a model citizen here, steals the receiver’s input every few hours if I have another device active.

avidiax · 4 hours ago

Yeah, the Apple TV isn't better so much as it is very aggressive. I usually have to long press the power button on the Apple TV remote to get it to power off and let go of my receiver.

Other devices like an nVidia Shield or the XBOX require that you press power/home a couple of times to take control of the receiver and switch inputs.

avidiax commented on Pro-democracy HK tycoon Jimmy Lai convicted in national security trial bbc.com/news/articles/cp8... · Posted by u/onemoresoop

thenanyu · 12 hours ago

When I was in my early 20s I used to think I was very clever for pointing out apparent hypocrisies. Now I realize how easily that devolves into “you are imperfect therefore you may never criticize anything”

Americans can never call out human rights abuses because of slavery. The British can never because of colonialism. Period. Forever.

If you find this line of argumentation compelling there’s no discussing anything with you.

avidiax · 11 hours ago

It goes beyond just pointing out hypocrisy. This is a well known propaganda strategy called "Whataboutism." [1] It's unfortunately a tremendously effective smokescreen that divides the audience and shuts down meaningful debate.

[1] https://en.wikipedia.org/wiki/Whataboutism

avidiax commented on Microsoft Copilot AI Comes to LG TVs, and Can't Be Deleted techpowerup.com/344075/mi... · Posted by u/akyuu

jzacharia · a day ago

I'd pay triple for an LG "dumb" TV. This is outrageous.

avidiax · 20 hours ago

Look up signage displays. Only problem with them is that they may be overly industrial and missing things that consumers would want, like Dolby Vision.

avidiax commented on LG TV's new software update installed MS Copilot, which cannot be deleted old.reddit.com/r/mildlyin... · Posted by u/bj-rn

irilesscent · 2 days ago

This is matching the levels of surveillance in north Korea. They also have software that takes pictures of your screen every few seconds.

avidiax · 2 days ago

It does this for HDMI inputs as well, BTW.

Using such a TV as a computer monitor sounds dicey. There will eventually be a data breach of the uploaded screenshots, assuming they aren't able to fingerprint entirely on device.

avidiax commented on Pdsink: USB Power Delivery Sink library for embedded devices github.com/pdsink/pdsink... · Posted by u/zdw

rcxdude · 4 days ago

The other issue with USB PD without a battery is that most chargers with multiple ports will drop the connection and renegotiate if any of the ports are plugged or unplugged (whether they need to in order to supply the new device or not).

(Relatedly, there's an empty niche in the market for a USB-C power bank that can act as a UPS: able to charge and discharge at the same time without interrupting the discharge port when the charge port is disconnected)

avidiax · 3 days ago

> Relatedly, there's an empty niche in the market for a USB-C power bank that can act as a UPS: able to charge and discharge at the same time without interrupting the discharge port when the charge port is disconnected

I think there's a soft version of this already available. The term is "pass-through" charging. The power bank that I have [1] will charge itself and the devices at the same time (albeit at reduced rates suitable for overnight charging).

I agree that it would be super useful to have a device that is explicitly designed to provide maybe 5V/5A for a Raspberry Pi 5 without interruption, and perhaps double as a power bank.

[1] https://www.amazon.com/dp/B0DHRYDNXL

avidiax commented on Pdsink: USB Power Delivery Sink library for embedded devices github.com/pdsink/pdsink... · Posted by u/zdw

prezk · 4 days ago

You could run on 5V with a boost voltage converter to 12V. For extra credit, you could run the USB-PD off 5V, negotiate 12V and only then switch it to the load.

avidiax · 4 days ago

If I need 12V/1A, then that suggests I need 5V/2.4A even with 100% efficiency. Without negotiating anything, a device shouldn't draw more than 5V/0.5A.

That's not to say that a boost converter doesn't have value, but it still leaves a gap where there could be confusion.

The confusion or complexity even multiplies if the device has additional USB-C for data transfer. In that case, you either have to mark one port as being the "power in" port, or you have to support power in and data out on all the ports, which gets complicated and expensive.

It would be a great move by the USB IF to think through this sort of thing more carefully. Right now the USB-c connector is so overloaded in terms of power, display modes, thunderbolt, speeds, etc. that it's very hard to predict whether two USB-c devices will connect and at what power or speed and with what capabilities. For power, it would be helpful to require supplies to have a standardized status LED so that e.g. green means that the supply is providing the highest power allowed by the device (not the supply), yellow means there's been a compromise, and red suggests an error condition.

avidiax commented on Pdsink: USB Power Delivery Sink library for embedded devices github.com/pdsink/pdsink... · Posted by u/zdw

avidiax · 4 days ago

I looked at adding USB-PD as a replacement for a 12V barrel-plug power supply in a recent project.

One big issue that came up (and killed the idea) is that if you are not battery powered, then putting a USB-C power input on your device that will only work if you can negotiate 12V+ with adequate current will just cause confusion. In my case, I don't think I could even boot to an error message on 5V.

Phones and the like don't have this issue, since they are still usable (charging slowly) on 5V, but can make use of higher voltages and currents to charge faster.

So I guess my question for the implementer is how booting & negotiating on 5V and then accepting higher voltage is likely to work in practice.

avidiax commented on RFC 6677 DNS Transport over TCP – Implementation Requirements (2016) ietf.org/rfc/rfc7766.txt... · Posted by u/1vuio0pswjnm7

PunchyHamster · 4 days ago

quadrupling first query time wouldn't be acceptable. And now server have to keep some state per client so more requirements

avidiax · 4 days ago

If the DNS server is actually local like it's supposed to be, it should have just a few ms ping. Quadrupling that just once is no big deal. The user won't even notice, since every OS does lots of background DNS activity before the user even opens an app or browser.

Saying that 2xRTT is a deal-breaker is like saying TCP in general is a deal breaker.

State per client is pretty simple. Use a bloom filter to decide if a client IP is ok for UDP, and slowly set bits to zero at random to force gradual eviction. With a secret nonce per server, the attacker can't engineer collisions except by controlling lots of IPs. For IPv6, just treat blocks above a certain size (e.g. a /48) as equivalent.

And again, this should be the default. Someone that is seriously trying to run an open resolver should have their own fork of the source code and adjust this as they need. The small-time operators that accidentally make their resolvers open won't notice a bloom filter or a slow initial lookup.

avidiax commented on RFC 6677 DNS Transport over TCP – Implementation Requirements (2016) ietf.org/rfc/rfc7766.txt... · Posted by u/1vuio0pswjnm7

avidiax · 4 days ago

I would like to see DNS servers require each client to establish one TCP connection to be allowed to use UDP thereafter.

If this were the default on DNS servers, then DNS amplification attacks would be nearly impossible. They rely on spoofing a DNS request from the victim, and amplify because the response may be many times larger than the request. If TCP were required to be used before UDP responses can be received, then the victim would have to be first tricked into making a DNS request over TCP to each public DNS server.

The DNS Cookies standard (RFC 7873) doesn't do much to stop this, since it is impractical to fail queries from non-cookie clients.

DNS over TCP is supposed to be supported, so implementing this will push firewall admins in the right direction (allow both TCP/UDP outbound on 53).

avidiax commented on Detecting AV1-encoded videos with Python alexwlchan.net/2025/detec... · Posted by u/surprisetalk

monster_truck · 9 days ago

I exclusively download av1 encodes from places like tbp. It has fantastic quality for the filesize, and AV1 also benefits the most from the trick of encoding sdr content in 10 bit (more accurate quantization at a smaller size). Crazy that we can fit ~two hours of 1080p video at better than netflix quality (they bias their psnr/etc a little low for my eyes) on a single CD.

I'm not sure it's fair to call reencodes expensive. Sure, its relatively expensive to using ffprobe, but any 4 series nvidia gpu with 2 nvenc engines can handle five? simultaneous realtime encodes, or will get up to near 180fps if it isn't being streamed. Our "we have aja at home" box with four of them churned through something like 20,000 hours of video in just under two weeks.

avidiax · 9 days ago

My understanding is that you shouldn't be using HW accelerated encoding for any archival purpose except realtime capture.

The PSNR/bitrate is much lower for HW encode, but the encode rate is typically realtime or better. That's a great tradeoff if you are transcoding so that a device with limited bandwidth can receive the video while streaming, or so that you can encode a raw livestream from a video capture or camera. It's not so great if you are saving to disk and planning to watch multiple times.