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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)."
Well, it starts with the "Loudness War" Record companies/radio stations compete to make everything louder, because the louder the music is coming over the air, the more likely the listener is to notice it. I don't see how that would help youtube though, because we're not listening to youtube in the background like we are to the radio.
Wouldn't another solution be to sneak past the entire recompression process by submitting a .flv video that meets YouTube's requirements to avoid recompression? Or would the compression on audio (not the same type of compression, the one this article is talking about) still be forced on these?
By the way to improve the trick, what you could do is detect the envelope of your sound, a modulate your 19 kHz sine with an envelope complementary so that the two envelopes would sum up to a flat line, so your 19 kHz envelope would be f(t) = 1 - original_sound_envelope(t).
You just got troll'd!
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.
It surprises me after all these years, audio formats don't provide recording information about the dynamics of the waveform.
Cameras write EXIF information into JPEG files, why can't we have something similar for audio so we don't have to adjust the volume all the time?
You don't have to be an audiophile to appreciate good audio. I have a custom amp next to my computer into which I've plugged headphones. Find anyone with a pair of headphones, and you'll find an amp, too. Either that, or a deaf person who's been tortured by a bad Flash file.
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...
It still matters what they do. This kind of high compression is unsuitable for most material, yet they're insisting on it. Not only does it completely kill the dynamic range - imagine going to see a classical music concert and the entire concert is played at the exact same volume, no crescendos or decrescendos - that lack of dynamic range also dramatically quickens ear fatigue. What they're doing is great if they want people to stop listening (and therefore likely watching) YouTube videos as much. Otherwise, it's a really dumb idea.
Using a noise gate to solve YouTube's poor decision is not very realistic - that's trying to get thousands and thousands of different people to fix something caused by YouTube trying to solve what wasn't really much of a problem. What's more, noise gate + high compression leads to Charlie Brown Special kinds of voice tracks and very limited musical choices - e.g., in a classical concert, instead of the quiet parts being just as loud as the loud parts, some of the quiet parts will simply be cut to silence. Noise gate + high compression can be cute for a bit in dialogue, and when done to a particular instrument - but not every instrument in a song - you can get some cool effects from it, but it's shitty thing for YouTube to require of people. It may be enough to force some users away.
WPLJ 95.5 in NYC knew this very well back in the 70's they' use massive audio compression to keep the modulation index of the carrier at 95.5%... That needle just say there!
My station WDJF 107.9 Westport CT cared about audio quality. The MI followed the full amplitude of the source audio. Fed by 2 channels of full 15 khz equalized ma-bell-telco pairs. We sounded good! But PLJ was much much louder.