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Sneaking Past Heavy-Handed Audio Compression on YouTube

niceone writes "Recently YouTube seems to have started applying extreme compression to the audio of uploaded clips. This is the type of compressions used by radio stations to make everything louder, but in this case applied extremely badly. In quiet passages, breathing and shuffling become overpoweringly loud. A gently plucked guitar chord becomes a distorted thud. Listen to an example here. And here's what it could sound like — still not perfect, but a whole lot better. The fixed version is thanks to a workaround proposed by Sopranoguitar — the idea is to turn down the audio and mix in a high frequency sine wave (I used 19kHz). The sine wave fools YouTube's compressor into thinking that the file is at a uniform level (and does not need the volume changing at all) but is filtered out by the encoding process (so, no need to worry about deafening any dogs)."

12 of 234 comments (clear)

  1. Update by niceone · · Score: 5, Informative

    After some more testing it seems that there is a problem with high quality mode. With the tone and sample rate I used (19kHz and 44.1k) at least the high quality encoder whistles at, some other frequency. Sounds like somewhere less than 10kHz to me.

    I hope YouTube fix this soon.

    1. Re:Update by Anonymous Coward · · Score: 5, Interesting

      It looks to me like Google have done this on purpose to stop people uploading high quality audio with a still image. A lot of the music I've been listening too recently has been from youtube, I'm sure I'm not the only one...

  2. Standards by Dan+East · · Score: 5, Funny

    YouTube is just trying to enforce a standard level of quality to the content. Everyone expects crappy video with lots of compression artifacts, so the audio might as well follow suite.

    --
    Better known as 318230.
  3. Brevity Required by Tablizer · · Score: 5, Funny

    Can someone post an example I could possibly listen to for more than one second?

    No
         

    1. Re:Brevity Required by RealGrouchy · · Score: 5, Funny

      CLICK THUD TICK SSSS No FWWWW CLUNK CLICK

      I'm sorry--what did you say?

      - RG>

      --
      Hey pal, this isn't a pleasantforest, so don't waste my time with pleasantries!
  4. Re:This hurts by drspliff · · Score: 5, Informative

    The worst examples I've seen have been videos of a lecture/speech, and while the main speaker has a microphone it also picks up sound from around the auditorium or lecture hall.

    Normally this is fine as we have all become accustomed to faint background noise, with this extreme compression the faintest cough or shuffling in the audience sounds is as loud as the person speaking and is thus very distracting.

    Considering most of the lectures I view are 30+ minutes long this really pisses me off.

  5. Warning from ccalam in the second video by Looce · · Score: 5, Interesting

    The high quality version of the audio will have the 19 (or up to 22.1) kHz sine wave you choose to use in your video upload. So this is a trade-off of quality (high-quality = eek!) versus lack of unwanted range compression (low-quality = listenable, for lack of a better word).

    FWIW, I can hear 19 kHz waves. So this trade-off affects me.

  6. Re:and who came up with it? by Anonymous Coward · · Score: 5, Funny

    I have to keep jacking the knob up and down.

    To YouTube videos? Sicko!

  7. Re:and who came up with it? by mdmkolbe · · Score: 5, Insightful

    I don't think YouTube is trying to run a loudness war, but rather trying to fix up a lot of amateurish recordings that are uploaded with bad audio. I can't tell you how many recordings on the net are either way to quiet (e.g. I can't hear speech even at max volume) or too loud and that change in mid-video (e.g. person walks away from or closer to mic). Despite their good intentions, though, it seems to have fallen prey to the "Clippy" effect.

    What YouTube needs to do is have a little check-box on uploads that indicates whether to apply the auto-balance. And in case an uploader asks for no auto-balance when they really shouldn't (e.g. they think they know but don't) there should be a side link to listen to the auto-balanced version.

  8. Re:and who came up with it? by billcopc · · Score: 5, Informative

    Louder is one thing, compression is another.

    Compression can help bring out the faint natural harmonics in a sound, making it "warmer", not unlike an overdriven tube amp. These harmonics are like ear candy to most people, subliminally making the sound more enjoyable.

    Radio stations do it for various reasons, one is it helps them sustain peak output power. Another is that the average radio is a cheap chinese gadget that sounds like liquid ass, so the compression actually helps with the sound quality on those devices. When you also consider where radio is often heard, e.g. malls, outdoor venues, cube offices, you realize these are all substandard listening environments where high dynamic range really means you lose half the sound, so the compression again helps with perceived quality by driving most of the content above the noise threshold.

    There are plenty of good reasons for sound compression, but its use should be toggled by the user, and for the love of god, give it some sane thresholds! For most content, anything above 4x compression is overkill!

    --
    -Billco, Fnarg.com
  9. Re:and who came up with it? by billcopc · · Score: 5, Funny

    But what if you move away from the mic to breathe ?

    Chocolate Rain
    *whoooosh*
    Youtube makes my breathing loud again
    Chocolate Rain
    *whoooosh*
    My eardrums are whimpering in pain

    --
    -Billco, Fnarg.com
  10. Re:and who came up with it? by archeopterix · · Score: 5, Funny

    This is just in. Studies have shown that on a popular site named Slashdot LOUD COMMENTS ARE MODERATED BETTER THAN QUIET ONES!!!