13 ms·

FLAC 1.3.4

176 points by libele 5y ago

brnt 5y ago
Shoutout to LossyWAV (formerly LossyFLAC) [1]. It's a preprocessor to lossless codecs shaping noise such that higher compression ratios can me reached. It works out much better than that sounds like. 1. https://wiki.hydrogenaud.io/index.php?title=LossyWAV https://wiki.hydrogenaud.io/index.php?title=LossyWAV
- tjoff 5y ago
  It works out much better than that sounds like. That... doesn't sound good ;) Really cool idea, though more comparable to lossy compression I guess.
- sprash 5y ago
  This reduces the bitrate by about 3 times. Even at the lowest bitrate at about 300 kbps I can't even hear the slightest difference to the original. Impressive, but I wonder what it would sound like when you reduce the bitrate even further. Would it be competitive with mp3?
  - out_of_protocol 5y ago
    This at 300kbps vs opus 300kbps? mp3 is not a good comparison target
    - sprash 5y ago
      Since the decoder complexity of flac is much lower than that of opus LossyWAV easily wins this competition at 300 kbps. I just wonder what the compression artifacts with LossyWAV would sound like if you push the bitrate down further (like e.g. 128 kbps). Sadly the command line tool does not allow that.
      - out_of_protocol 5y ago
        Would be interesting. Unlikely to work out though. On other note, opus 128 kbps is transparent (in my tests i can distinguish 100kbps files at most), with safety margin 256 kbps should be enough for all practical purposes (except archiving). There are other worser codecs around, e.g. LDAC (best Bluetooth codec) 660kbps vs 990kbps is very noticable (cant setup the same way to compare 990kbps LDAC vs 128kbps opus)
      - edave64 5y ago
        What are you doing with it that opus decoding complexity is any kind of barrier?
  - Aachen 5y ago
    I mean, you don't need flac to have audio quality where people can't distinguish in double blind test. Something like 160kbps (iirc, ±30) Opus does the job as well. (Mp3 is way less efficient and depending on the encoder it can have characteristic artifacts. Vorbis was already better, but opus blows that away. Software support for opus is nearly as good as mp3 since recently. We should either stop considering mp3 the default lossy format or hack it into a container format so audio files can have opus inside while carrying the familiar mp3 extension for the 90s folk to be happy about.)
    - SSLy 5y ago
      Ogg was merely a (very bad) container, you're probably thinking about Vorbis.
      - Aachen 5y ago
        Ah yes, I keep mixing those up. Edited, thanks.
- adastra22 5y ago
  > It's a preprocessor to lossless codecs shaping noise... So it's a lossy compression? Why use FLAC then?
  - namibj 5y ago
    Sounds more like trellis quantization in near-lossless H.264, explicitly trading coding cost of details against psychovisual impact of said details.
    - astrange 5y ago
      That's psy-rd (in x264 terms). Trellis quantization is just a more optimal way to divide numbers - think of it like rounding to nearest instead of down. "optimal" means "optimal rate-distortion tradeoff" and "distortion" means whatever you want it to, but usually it's difference between original and compressed pixels (absolute error/SAD/PSNR). That can look blurry, because given all alternatives with the same SAD, blurry ones compress more. So psy-rd changes the definition of distortion to add a "has similar amount of noise" factor. That's very far from human optimal (if anything it's SSIM optimal) but it's free detail. Uses the same quantization to get there, though.
  - astrange 5y ago
    It's just a hobby project, and the structure isn't too different from how other lossy codecs work. (Or lossless ones - you can construct one of those from any lossy one just by sticking the difference from the original on the end.) Most codecs sacrifice transparency to reach a bitrate and this one does the opposite.
    - ptx 5y ago
      > Most codecs sacrifice transparency to reach a bitrate and this one does the opposite. That's what LAME's presets and the Ogg Vorbis quality settings do as well, isn't it?
      - astrange 5y ago
- edave64 5y ago
  Reminds me of https://pngquant.org/ https://pngquant.org/ Same concept just for making images more efficient for PNG
  - bmn__ 5y ago
    Better: https://news.ycombinator.com/item?id=26646035 https://news.ycombinator.com/item?id=26646035
corysama 5y ago
How cheap does storage have to get before people stop bothering to use FLAC? By my calculations, $65 will buy you a 4TB hard drive which can hold over 6,000 hours of uncompressed CD quality PCM. With FLAC you might squeeze 9,000-12,000 hours in. But, is that really worth the bother? I know it’s not obviously relevant to consumers, but an uncompressed PCM .wav file is a format that any high school coder can figure out completely. FLAC on the other hand has had decades of work put into it. It is an engineering marvel. I just wish people would think simpler than “engineering marvel” when it comes to archival formats when the simplest conceivable format works just about as well… :$ Edit: Many people are bringing up MP3/Ogg/Opus, compressing podcasts, how silly it would be to toss out all forms of audio compression. To be clear, MP3/Ogg/Opus make perfect sense to me. They are complicated. But, in return you get 8-12x the content at great (not perfect) quality. FLAC on the other hand Is at least as complicated, has a lot less widespread support and has an ROI of 1.5-2x… As a consumer, I can see that 2x in return for a modest amount of hassle can be an OK deal in constrained situations -like price-gouged mobile storage. As an engineer who has maintained software systems over many years, the complexity of FLAC compared to trivial PCM as an archive format makes me a sad, cranky, old greybeard.
- xorcist 5y ago
  There is no inherent advantage to bigger files. You could losslessly upsample those wav files of yours to some insane precision if all you wanted was bigger files. If the argument instead is that raw audio is a simpler format, the answer is that everybody wants some sort of container that carry metadata.
- poink 5y ago
  People will stop bothering with FLAC the instant they care about the specifics of the file format more than saving even the most trivial amount of space on their devices. Never, in other words.
- raverbashing 5y ago
  "complexity of FLAC"? As complex as gzipping a file Sounds like the people who are surprised at their end of month AWS bill because they couldn't bother to optimize anything.

176 points by libele 5y ago

brnt 5y ago

Shoutout to LossyWAV (formerly LossyFLAC) [1]. It's a preprocessor to lossless codecs shaping noise such that higher compression ratios can me reached. It works out much better than that sounds like. 1. https://wiki.hydrogenaud.io/index.php?title=LossyWAV https://wiki.hydrogenaud.io/index.php?title=LossyWAV

tjoff 5y ago
It works out much better than that sounds like. That... doesn't sound good ;) Really cool idea, though more comparable to lossy compression I guess.
sprash 5y ago
This reduces the bitrate by about 3 times. Even at the lowest bitrate at about 300 kbps I can't even hear the slightest difference to the original. Impressive, but I wonder what it would sound like when you reduce the bitrate even further. Would it be competitive with mp3?
- out_of_protocol 5y ago
  This at 300kbps vs opus 300kbps? mp3 is not a good comparison target
  - sprash 5y ago
    Since the decoder complexity of flac is much lower than that of opus LossyWAV easily wins this competition at 300 kbps. I just wonder what the compression artifacts with LossyWAV would sound like if you push the bitrate down further (like e.g. 128 kbps). Sadly the command line tool does not allow that.
    - out_of_protocol 5y ago
      Would be interesting. Unlikely to work out though. On other note, opus 128 kbps is transparent (in my tests i can distinguish 100kbps files at most), with safety margin 256 kbps should be enough for all practical purposes (except archiving). There are other worser codecs around, e.g. LDAC (best Bluetooth codec) 660kbps vs 990kbps is very noticable (cant setup the same way to compare 990kbps LDAC vs 128kbps opus)
    - edave64 5y ago
      What are you doing with it that opus decoding complexity is any kind of barrier?
- Aachen 5y ago
  I mean, you don't need flac to have audio quality where people can't distinguish in double blind test. Something like 160kbps (iirc, ±30) Opus does the job as well. (Mp3 is way less efficient and depending on the encoder it can have characteristic artifacts. Vorbis was already better, but opus blows that away. Software support for opus is nearly as good as mp3 since recently. We should either stop considering mp3 the default lossy format or hack it into a container format so audio files can have opus inside while carrying the familiar mp3 extension for the 90s folk to be happy about.)
  - SSLy 5y ago
    Ogg was merely a (very bad) container, you're probably thinking about Vorbis.
    - Aachen 5y ago
      Ah yes, I keep mixing those up. Edited, thanks.
adastra22 5y ago
> It's a preprocessor to lossless codecs shaping noise... So it's a lossy compression? Why use FLAC then?
- namibj 5y ago
  Sounds more like trellis quantization in near-lossless H.264, explicitly trading coding cost of details against psychovisual impact of said details.
  - astrange 5y ago
    That's psy-rd (in x264 terms). Trellis quantization is just a more optimal way to divide numbers - think of it like rounding to nearest instead of down. "optimal" means "optimal rate-distortion tradeoff" and "distortion" means whatever you want it to, but usually it's difference between original and compressed pixels (absolute error/SAD/PSNR). That can look blurry, because given all alternatives with the same SAD, blurry ones compress more. So psy-rd changes the definition of distortion to add a "has similar amount of noise" factor. That's very far from human optimal (if anything it's SSIM optimal) but it's free detail. Uses the same quantization to get there, though.
- astrange 5y ago
  It's just a hobby project, and the structure isn't too different from how other lossy codecs work. (Or lossless ones - you can construct one of those from any lossy one just by sticking the difference from the original on the end.) Most codecs sacrifice transparency to reach a bitrate and this one does the opposite.
  - ptx 5y ago
    > Most codecs sacrifice transparency to reach a bitrate and this one does the opposite. That's what LAME's presets and the Ogg Vorbis quality settings do as well, isn't it?
    - astrange 5y ago
edave64 5y ago
Reminds me of https://pngquant.org/ https://pngquant.org/ Same concept just for making images more efficient for PNG
- bmn__ 5y ago
  Better: https://news.ycombinator.com/item?id=26646035 https://news.ycombinator.com/item?id=26646035

corysama 5y ago

How cheap does storage have to get before people stop bothering to use FLAC? By my calculations, $65 will buy you a 4TB hard drive which can hold over 6,000 hours of uncompressed CD quality PCM. With FLAC you might squeeze 9,000-12,000 hours in. But, is that really worth the bother? I know it’s not obviously relevant to consumers, but an uncompressed PCM .wav file is a format that any high school coder can figure out completely. FLAC on the other hand has had decades of work put into it. It is an engineering marvel. I just wish people would think simpler than “engineering marvel” when it comes to archival formats when the simplest conceivable format works just about as well… :$ Edit: Many people are bringing up MP3/Ogg/Opus, compressing podcasts, how silly it would be to toss out all forms of audio compression. To be clear, MP3/Ogg/Opus make perfect sense to me. They are complicated. But, in return you get 8-12x the content at great (not perfect) quality. FLAC on the other hand Is at least as complicated, has a lot less widespread support and has an ROI of 1.5-2x… As a consumer, I can see that 2x in return for a modest amount of hassle can be an OK deal in constrained situations -like price-gouged mobile storage. As an engineer who has maintained software systems over many years, the complexity of FLAC compared to trivial PCM as an archive format makes me a sad, cranky, old greybeard.

xorcist 5y ago
There is no inherent advantage to bigger files. You could losslessly upsample those wav files of yours to some insane precision if all you wanted was bigger files. If the argument instead is that raw audio is a simpler format, the answer is that everybody wants some sort of container that carry metadata.
poink 5y ago
People will stop bothering with FLAC the instant they care about the specifics of the file format more than saving even the most trivial amount of space on their devices. Never, in other words.
raverbashing 5y ago
"complexity of FLAC"? As complex as gzipping a file Sounds like the people who are surprised at their end of month AWS bill because they couldn't bother to optimize anything.