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Joined 2 years ago
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Cake day: June 5th, 2023

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  • I agree that, theoretically speaking, YouTube might be protecting some end users from this type of attack. However, the main reason YouTube re-encodes video is to reduce (their) bandwidth usage. I think it’s very kind towards YouTube to view this as a free service to the general public, when it’s mostly a cost-cutting measure.


  • Good point, though I believe you have to explicitly enable AV1 in Firefox for it to advertise AV1 support. YouTube on Firefox should fall back to VP9 by default (which is supported by a lot more accelerators), so not being able to decode AV1 shouldn’t be a problem for most Firefox-users (and by extension most lemmy users, I assume).


  • About the “much higher CPU usage”: I’d recommend checking that hardware decoding is working correctly on your device, as that should ensure that even 4K content barely hits your CPU.

    About the “less sharper image”: this depends on your downscaler, but a proper downscaler shouldn’t make higher-resolution content any more blurry than the lower-resolution version. I do believe integer scaling (eg. 4K -> 1080p) is a lot less dependant on having a proper downscaler, so consider bumping the resolution up even further if the video, your internet, and your client allow it.


  • I believe YouTube always re-encodes the video, so the video will contain (extra) compression artefacts even if you’re watching at the original resolution. However, I also believe YouTube’s exact compression parameters aren’t public, so I don’t believe anyone outside of YouTube itself knows for sure which videos are compressed in which ways.

    What I do know is that different content also compresses in different ways, simply because the video can be easier/harder to compress. IIRC, shows like last week tonight (mostly static camera looking at a host) are way easier to compress than higher paced content, which (depending on previously mentioned unknown parameters) could have a large impact on the amount of artefacts. This makes it more difficult to compare different video’s uploaded at their different resolutions.



  • Unless your initial recordings were lossless (they probably weren’t), recompressing the files with a lossless flag will only increase the size by a lot. Lossless video is HUGE, which is why almost no one actually records/saves it. What you’re probably looking for is visually lossless transcoding, where you do lose some data, but the difference is too small for most people to notice.

    My recommendations:

    1. Go to your recording software and change the setting to better compress your videos the first time around. Compressing once generally gives a better quality to size ratio than compressing twice. It’s therefore best if your recording software get it right first time, without you having to keep on recompressing your videos.
    2. When tinkering with encoding setting, trying to find what works best for you, it might be useful to install Identity to help you compare the original files and one or more transcoded version(s).
    3. Don’t try to recompress the audio; you’ll save very little space, and the losses in quality become perceptible much faster than video. When using ffmpeg, the “-c:a copy” flag should simply copy the original audio to the new file, without any change in quality or size
    4. I’d recommend taking some time to read through the ffmpeg encoding guides. H265 and AV1 are good for personal archiving, with AV1 providing better compression ratios at the cost of much slower encoding. You could also choose VP9, which is similar in compression ratio and encoding speed to h265.
    5. You’ll have to choose between hardware and software encoding. Hardware encoding can (depending on your specific hardware and settings) be 10-100x faster than software, but software generally gives better compression ratios at similar qualities. You should test this difference for yourself and see if the extra time is worth it for the extra quality. Do keep in mind that AV1 hardware encoding is only supported by some of the most recent GPU’s (rx7000 and rtx4000 from the top of my head). If you don’t have one of those GPU’s, you’ll either have to choose software encoding or pick a different codec.

  • Maxy@lemmy.blahaj.zonetoMemes@lemmy.mlDear iPhone users:
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    3 months ago

    Not to be an unfunny nitpicker (I don’t know why I’m denying this, that kinda the whole point), but all iphones do have lossless audio streaming via AirPlay. I’m assuming that you specifically meant Bluetooth streaming, but then you should’ve said so. Furthermore, normal aptx isn’t high resolution, only aptx HD and aptx adaptive are. The phone does support aptx HD as well, but once again, you could’ve said so from the start (though 3 characters more or less might make a significant difference to most memes, this one certainly wouldn’t have had that problem)


  • Luxury! My homeserver has an i5 3470 with 6GB or RAM (yes, it’s a cursed 4+2 setup)! </badMontyPythonReference>

    Interesting, I also run Nextcloud and pihole, and vaultwarden, jellyfin, paperless-ngx, gitea, vscode-server and a minecraft server (every now and then).

    You’re right that such a system really does show its age, but only when doing multiple intensive tasks at the same time. I try not to backup my photos to Nextcloud while running minecraft, for example, as the imagine identification task pins my CPU at 100%. So yes, I agree, you’re probably not doing anything out of the ordinary on your setup.

    The point I was trying to make still stands though, as that pi 2B could run more than I would’ve expected beforehand. I believe it once even ran jellyfin, a simple file server, samba, and a webserver with a simple HTML website. Jellyfin worked just fine, as long as the pi didn’t have to transcode (never got hardware transcoding to work).

    It is funny that you should run out of memory, seeing as everything fits (albeit, just barely) on my machine in 1/5 the memory. Would de overhead of running VM’s account for such a large difference?


  • Coming from someone who started selfhosting on a pi 2B (similar-ish specs), you’d be surprised. If you don’t need anything fast or fancy, that 1GB will go a long way, and plenty of selfhosted apps require very little CPU. The only real problem I faced was that all HTTPS-related network tasks were limited at ~3MB/s, as that is how fast my pi could encrypt the data (presumably, I just saw my webserver utilising the entire CPU and figured this was the most likely explanation)


  • I’ve had good experiences with whisper.cpp (should be in the AUR). I used the large model on my GPU (3060), and it filled 11.5 out of the 12GB of vram, so you might have to settle for a lower tier model. The speed was pretty much real time on my GPU, so it might be quite a bit slower on your CPU, unless the lower tier models are also a lot faster (never tested them due to lack of necessity).

    The large model had pretty much perfect accuracy (only 5 or so mistakes in ~40 pages of transcriptions), and that was with Dutch audio recorded on a smartphone. If it can handle my pretty horrible conditions, your audio should (hopefully) be no problem to transcribe.


  • It depends what you’re optimising for. If you want a single (relatively small) download to be available on your HDD as fast as possible, then your current setup might be better (optimising for lower latency). However, if you want to be maxing out your internet speeds at all time and increase your HDD speeds by making the copy sequential (optimising for throughput), then the setup with the catch drive will be better. Keep in mind that a HDD’s sequential write performance is significantly higher than its random write performance, so copying a large file in one go will be faster than copying a whole bunch of random chunks in a random order (like torrents do). You can check the difference for yourself by doing a disk benchmark and comparing the sequential vs random writes of your drive.


  • Maxy@lemmy.blahaj.zonetoSelfhosted@lemmy.worldData HDD with SSD catch drive
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    4 months ago

    qBittorrent has exactly the option you’re looking for, I believe it’s called “incomplete download path” in the settings, letting you store incomplete downloads at a temporary path and moving them to their regular location when the download finishes. Aside from the download speed improvement, this will also lead to less fragmentation on your HDD (which might be part of the reason why it is so slow when downloading directly to it). Pre-allocating space could have the same effect, but I would recommend only using one of these two solutions at once (pre-allocating space on your SSD would only waste space)


  • It’s possible for a certain hardware/software setup not to support a certain codec. For example, my jellyfin client (Finamp) uses the iOS native decoders (afaik), which means opus files are practically broken. My music library (8000+ songs) contained exactly 1 lossy file, which just so happened to be an opus file. I decided to spend the extra ~20MB to standardise my entire library to flac files, ensuring I could play every song on all my devices.

    Edit cause I posted too soon: you are generally correct; only in very specific circumstances will you encounter compatibility issues like this one in the modern world. This is 100% apple being apple, and you can expect pretty much every other (reasonably modern) device to support all codecs you might encounter in the wild.


  • To add to the audio compression: it isn’t possible to further compress an mp3 file without losing any quality. You can either:

    1. Recompress to a lossy codec (mp3, aac, opus). This will lead to smaller file sizes if you set the bitrate lower than that of the input file, but it will always worsen the quality, no matter the bitrate.
    2. Recompress to a lossless format (flac easily being the best one). Going from a lossy to a lossless format will increase the file size (sometimes by quite a substantial amount), while keeping the same quality. There is very little reason for you to do this
    3. keep the original files (my recommendation)

    If you’re willing to spend some extra time learning about audio compression, you can download lossless files and compress those directly to whatever format and bitrate you want. The quality will be better than option 1 above, as the audio is only lossely compressed once instead of twice.




  • Maxy@lemmy.blahaj.zonetoMemes@lemmy.mlviolently cries and sobs
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    5 months ago

    “cis” and “trans” are prefixes denoting on what “side” something is. “cis” means “on this/our side”, while “trans” refers to “the other side”, for example:

    1. “Cisalpina” is how the Romans referred to their side of the Alps (modern day Italy), while “Transalpina” referred to land on the other side of the alps.
    2. There exist certain pairs of molecules with either a “cis” or “trans” prefix, depending on whether certain identical groups are on the same side or on opposite sides, respectively.

    The modern use of “cis” and “trans” is generally about gender. A cisgender person is someone whose gender identity aligns with their sex assigned at birth, while a transgender person is someone for whom that doesn’t hold true.

    In this meme, the person on the right is wearing a transgender flag for a shirt, and presumably offending the cisgender person on the left by calling them cis. The meme is making fun of the fact that some cisgender people consider “cis” an insult, when it really only is a neutral and non-offensive description.