suzumer

I wouldn't describe 4chan as karmaless. While the site bemoans the idea of upvotes (updoots), they'll also be the first to tell you how much they crave replies (which they call "you"s). We can see how much this affects the forum, with many people posting content, not because they think it is the best thing to post, but because they think it will get a reaction.

-filter_complex specifies a series of filters that accept inputs and return outputs. Any value contained in brackets ([]), is a value that can be input or output by a filter. [0:v],[0:a],[1:v],[1:a] are values supplied by ffmpeg representing the video and audio streams of the 1st and 2nd inputs, in this case input1.mp4 and input2.mp4.

The first filter, concat, takes in a set of synchronized audio and video segments, concatenates them, and returns the resulting audio and video clips. n specifies the number of segments, v specifies the number of output video clips, and a specifies the number of output audio clips. The results are saved to the values of [v] and [a] for video and audio respectively.

The eq filter then takes the [v] video returned by concat, and adjusts the value to a brightness of 0.3. For reference, 0 represent no change to the brightness.

This [v] value is then mapped to the output video using -map.

That being said, this filter isn't correct, as the [a] value is never used or mapped, so the filter would fail. The correct way to write the filter, if the intended use is to discard the audio, would be:

  -filter_complex "[0:v][1:v]concat[v];[v]eq=brightness=0.3[outv]"

I omitted the n,v, and a values in the concat filter, as they are by default 2,1, and 0 respectively.

Another way to visualize this filter in an imperative style would look like this:

  def filter(input0, input1) {
    v = concat(input0.v,input1.v);
    outv = eq(v,brightness=0.3);
    return outv;
  }

Don't the discrete cosine transforms that underlie most video codecs automatically remove noise, as noise is generally high frequency?

Yeah, i agree that linux gaming has become pretty painless, although VR gaming is still a big sore spot. If you want to see if a game runs smoothly with no tinkering, check https://www.protondb.com/. Any game listed platinum will run without tweaks on linux.

Yeah, that's the one i use, although i use firefox.

I used to be addicted to youtube, and the most effective method I found to limiting my consumption was using an extension called Unhook. It removes all recommendations and the shorts and trending tabs, so the only videos I can watch are those from channels I'm subscribed to, or videos that I search for.

You might be intereseted in these youtube archive scripts: https://github.com/TheFrenchGhosty/TheFrenchGhostys-Ultimate...

For external storage, I find it best to throw some cheap drives in an old desktop and run SAMBA. This allows me to use zfs on the drives, and SAMBA easily interfaces with Mac,Linux, and Windows.

It doesn't necessarily mean there are no security pins. I can easily rake open a Master Lock 140D, despite those having spool pins.

How does it compare with intel's quick sync video in terms of performance and supported codecs?

Elon musk is no friend of the climate. He proposed hyperloop to distract California from building its high speed rail system, a rail system that will do more to help the climate than any electric cars will.

I don't know if it is fair to say "well behind." There are certainly mssing features, such as CUDA and proper video encoding, but using an amd gpu on linux is a seamless experience. Using nvidia cards requires their proprietary driver, and it doesn't always work well.

It doesn't make sense. Based on what limited info is out there, the Pi 4's cpu is around 15 GFLOPS, and the GPU is roughly 32 GFLOPS. The cpu in my 4 year old laptop hits at least 58 GFLOPS single core and 216 GFLOPS multicore, on top of the 400 GFLOPS gpu. Considering that laptop cpus are much more accessible than Raspberry Pis (the 4gb model apparently going for $200 on amazon) and they're more performant, it makes no sense to benchmark on a raspberry pi. That doesn't even get into the fact that CUDA code (which most AI work uses) won't run, and the raspberry pi's GPU ecosystem appears to be a nightmare to work with [1]

[1] https://news.ycombinator.com/item?id=31147393

When using 64 bit floating point numbers with 54 bits of precision, (or likely in this case, complex values consisting of two 64 bit floats) and you use an algorithm which you can guarantee converges to within 55 bits of precision in X steps, you have found the closest representable solution. Yes, you don't know whether it's 1 + sqrt(17) or 0.9 + Sqrt[17.84...], but you know to a degree of precision that 95% of use cases need what the value is. I do understand what you are saying, but the parent comment was referring to a student factoring polynomials. You doubted what he did based on the fact that he couldn't exactly specify what the roots were. I just assumed that he likely found the roots to a reasonable accuracy and then factored with these approximated values. The parent never specified, but given doubting the authenticity of the comment or celebrating youthful ingenuity, I choose the latter. I understand what you are saying. Yes, you can not find the EXACT values of the roots, but within the context of this comment chain, I don't think that matters.

No closed form solution means we can't write out the solution cleanly using standard algebraic operations. You can still write iterative algorithms that converge on the solution, such as by solving for the eigenvalues of a matrix.

It harms those who are dependent on your income, such as your family.

I've only recently acquired a DSLR camera, so take what I say with a grain of salt, but I think the big advantage with DSLR cameras is battery life. DSLR cameras only need to activate the sensor when taking a photo, and especially with the large sensors that accompany DSLRs, this can help to extend the camera's battery life.

FFMPEG hasn't even implemented VVC yet, and neither have web browsers, so Netflix can't just make "a mere function call" to get H.266 support.

This may be one of the most asinine things I have read on this website. Child pornography is worse than a corrupt government. I would rather have my rights stripped from me and be sent to a concentration camp than for someone to force a child to have sex.

Based on my own research, I don't believe this information is correct. HDR10 video is encoded according to Rec 2100 [1], which states that the video is 10 bits and goes up to 10,000 nits. I know this to be true as I have written my own programs to encode HDR10 video. You are correct however that most HDR10 content is only encoded with a mastering luminance of 1000 nits [2]. According to this [3] forum post, all DV content (besides profile 9) is encoded using 10-bit HEVC stream. When people talk about 12-bit Dolby Vision, they are referring to Profile 7, which contains a full enhancement layer stored at a 1/4th the resolution, which contains the residual between the source and the Base Layer, allowing a player to decode the data to 12 bits. It appears [4], however, that most DV content only uses the minimal enhancement layer, which is only the dynamic metadata.

[1] - https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.2100-2-...

[2] - https://www.rtings.com/tv/learn/hdr10-vs-dolby-vision

[3] - https://avdisco.com/t/demystifying-dolby-vision-profile-leve...

[4] - https://forum.blu-ray.com/showpost.php?p=16546620&postcount=...

You obviously know more about this than I do, but when I watch a a well encoded Blu-ray that doesn't use Dolby Vision like Planet Earth 2, and I compare that to a dolby vision encoded disc, I fail to see a noticeable difference. And when I rip the RPU of a disc that uses dolby vision and look at some of the data [1], I again don't see enough to warrant this being a proprietary system, especially when we have HDR10+. So Dolby may have teams of calibrators and created certifications, at the end of the day I fail to see why this warrants being proprietary. Please let me know what Dolby Vision does better than HDR10+ or regular HDR, because at the end of the day I'm just a hobbyist and want to learn more about this space.

[1] https://pastebin.com/m5NfUTbc

Yes, it works with DTS. Here is the full list of supported codecs: https://www.ffmpeg.org/ffmpeg-all.html#Audio-Codecs

While Dolby did design the perceptual quantizer gamme (PQ) [1] that almost every HDR device today uses, they waived patenting it [2] when it was standardized in SMPTE 2084 [3]. Everything that is proprietary about Dolby Vision (everything except PQ gamma) is relatively mundane and just dynamic metadata.

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

[2] https://f.hubspotusercontent00.net/hubfs/5253154/Dolby%20208...

[3] https://ieeexplore.ieee.org/document/7291452

I've found that the easiest way to extract audio data from a Blu-ray movie is to rip the file using MakeMKV and then use FFMPEG to convert the audio data to my codec of choice be it wav, aac, opus, etc. FFMPEG takes care of identifying the right codec to decode.

Even HDR mastering monitors can only reach 2000 to 4000 nits [1], whereas PQ gamma goes up to 10000 nits. This is why most hdr streams contain metadata containing mastering display peak luminance.

[1] https://www.usa.canon.com/shop/p/dp-v3120

Dolby Vision supplements the HDR data already present in a video. For example, when you buy a Blu-ray disc that supports Dolby Vision, the disc contains several m2ts files containing HEVC encoded videos. Present within the HEVC stream is also the metadata, which supplies metadata for each frame. To see what this data is, I used[1], and then got the info for frame 1000 and saved it as a json in this [2] pastebin. As you can see, it contains info regarding the minimum and maximum PQ encoded values, the coefficients of the ycc to rgb matrix, among other things. This allows TVs to better display the HDR data, as currently, video data encoded using rec. 2020 color primaries with max light level of 10000 nits is far outside what current TVs are capable of displaying, so metadata showing max pq of a frame or scene allows these devices to make better decisions.

[1] https://forum.doom9.org/showthread.php?t=183479 [2] https://pastebin.com/m5NfUTbc

Youtube already has it's own HDR video codec with VP9. Also, HDR10+ and Dolby Vision aren't HDR formats, they're formats for storing dynamic metadata that can help TVs better display HDR video. The article seems to misinterpret what their purpose is. HDR video can be presented just fine without HDR10+ or Dolby Vision.

While the parent is incorrect about wait, he/she is correct about T-glottallization in the word button. The glottalization of the T in button is even listed in the wikipedia article you linked.

While I agree that Tolkien likely viewed the races of men, elves, and dwarves to be white, and a show that seeks to adapt his mythology while having a diverse cast will stray from Tolkien's vision, we run into an interesting problem: a LOT of money is being spent on this show. Amazon reportedly spent 250 million to acquire the rights, and another 500 million on the first season. The US Bureau of Labor Statisitics says that there are 51,600 working actors, and they earn on average $23.48 an hour. Assuming 2000 hours a year, that's $2.4 billion spent on acting a year, putting Amazon's current budget of $750 million at roughly a fourth of all money spent on acting. With this in mind, if Amazon were to only hire white actors, in order to be equitable towards those of other races, we would need to guarantee that $250 million went to projects with actors of other races, and those projects would need to be entirely multi-racial. If said projects were in abundance, than I wouldn't be opposed to an all white Rings of Power, but considering that the highest budget project with a majority multi-racial cast I can think of is Nope with a budget of $50 million (and even then there are still white actors), if a company wants to make a nearly $1 billion show, it is necessary for there to be at least some actors of other races. If the show had half the budget, or if there were more projects written by and for a black audience, then I would prefer that it is acted by only white people, but as it stands now, it makes sense for there to be diversity.

Exactly, isn't it a little hypocritical to say that twitter users are simply "infinitely scrolling through the bedlam", while posting on a website that requires scrolling for content discovery? I admit that Hacker News has magnitudes better content than twitter, but it's ironic nonetheless.