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FLAC 1.3.4

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Re: FLAC 1.3.4

#101

Post by astrange »

ptx wrote: post #84
astrange wrote: post #45

Earlier quoted context omitted.

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.

> 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?

Yep, but codecs tend to have maximum bitrates either because of design tradeoffs or to work with hardware decoders. MP3's is too small to be perfectly transparent on some things, like cymbals.

Re: FLAC 1.3.4

#102

Post by mixedbit »

corysama wrote: post #2

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…

IPhone 13 Pro starts from 128GB and you need to pay extra 500$ to get 1TB. For portable players 2x reduction in storage space is still significant.

Re: FLAC 1.3.4

#103

Post by nasduia »

astrange wrote: post #76
autoexec wrote: post #63

Earlier quoted context omitted.

> This is beyond insulting, especially since modern flagships also lack microSD expansion. They'll do everything they can to push people into using their cloud services. It erodes the concept of ownership when you have to ask for permission from another party to access your own stuff. The more dependent they can make you on them the better. Plus when I listen to an MP3 stored on my phone, there's no opportunity for 3…

Nothing about downloading an MP3 that says they can't put a targeted ad in it; there's podcasts that do that based on your IP. I assume the reason most don't is just how much more trustworthy it sounds when the host reads an ad script live in the episode. (I swear there was an episode of The Weeds where they read an ad for a therapy service for dogs.)

> Nothing about downloading an MP3 that says they can't put a targeted ad in it; there's podcasts that do that based on your IP. I assume the reason most don't is just how much more trustworthy it sounds when the host reads an ad script live in the episode.

I'm in the UK and noticed both kind of happening: an ad for LinkedIn (I think) was localised to use a UK example in several episodes of This American Life during the last year. It was spliced into the programs seamlessly and sounded just like any of their usual sponsorship segments.

I'm presuming they just edited a handful of versions of the program for their largest listener regions and there was no need to do anything on the fly except pick which to serve. Of course I paid little attention to the ad as I was distracted more by it being the first time I'd noticed that kind of localisation.

Re: FLAC 1.3.4

#104

Post by dale_glass »

astrange wrote: post #79
dale_glass wrote: post #72

Earlier quoted context omitted.

Well, I say "black magic" because at least to me it's a quite mysterious creation. But I'm no audio engineer. It's a lossy codec that's for some reason fixed rate, and shrinks audio by exactly 1/4th. The resulting quality is very good (works perfectly fine for music), and it's much faster than Opus. It retains stereo and high frequencies and sounds just fine. I'm sure there's a tradeoff somewhere, but it's certainly…

Yeah, it sounds like ADPCM with a fixed ratio like that. It's extremely simple and adds no latency, which are both good for streaming. Usually a fixed compression ratio is a terrible tradeoff, but for streaming it kind-of makes sense.

I don't think it's ADPCM since it sounds really good. I'm not an audiophile or have done any comprehensive testing, but it' the kind of quality a normal person would use for music without complaining.

Re: FLAC 1.3.4

#105

Post by xorcist »

corysama wrote: post #2

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…

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.

Re: FLAC 1.3.4

#106

Post by bmn__ »

edave64 wrote: post #75
brnt wrote: post #16

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

Reminds me of https://pngquant.org/ Same concept just for making images more efficient for PNG

Better: https://news.ycombinator.com/item?id=26646035

Re: FLAC 1.3.4

#107

Post by grumpyprole »

astrange wrote: post #80
grumpyprole wrote: post #28

Earlier quoted context omitted.

The FLAC decoder has been almost completely integer for a long time (and may now be completely so). Apple Music and iOS still do not play FLAC, which is one significant reason why I won't buy an iPhone. Transcoding my entire music library certainly isn't "just works".

iOS supports FLAC, you can play it in Safari and the Files app. It's true you can't add it to the Music app, but you can use another app. Also, the $9 Apple headphone dongle is objectively superior to most audiophile DACs, which isn't surprising since it has a larger R&D budget than that entire industry. (Same goes for Google's IIRC.)

I would guess these days, many people buy audiophile DACs for the amplifier stage, for use with demanding high impedance headphones. However, there have been some really bad phone DACs in the past, the Qualcomm audio from the Note4 that I used to own sounded significantly worse than the iPhone using IEMs. What are people measuring with regard to the Apple dongle? Is it "objectively superior" with regard to multiple measurements?

It shouldn't be too hard to build a decent DAC and amp stage, at least for ear buds and IEMs, it's just that many manufacturers (e.g. Samsung / Qualcomm) don't care. Apple sell music and so probably should care more.

Re: FLAC 1.3.4

#108

Post by TonyTrapp »

Dylan16807 wrote: post #58
erdewit wrote: post #50

Earlier quoted context omitted.

Other lossy compression methods generally happen in the frequency domain and, depending on the type of music, can introduce audible distortions. This preprocessor on the other hand throws away some of least significant bits to save data. This increases the quantization noise but has no other sort of artifacts. The quantization noise can be dithered to fall in the higher frequencies (noise shaping) and is generally no…

Doesn't 16 bit audio already require dithering to capture the full audible dynamic range? That makes me worry somewhat about cutting more bits and layering dithers on dithers.

While it's good practice, a 16-bit recording is usually not exactly ruined by not dithering it. 96dB dynamic range is a lot.

Re: FLAC 1.3.4

#109

Post by dangravell »

chungy wrote: post #24
corysama wrote: post #17

Earlier quoted context omitted.

.wav files are really just https://en.m.wikipedia.org/wiki/Resource_Interchange_File_Fo... It’s trivial to put a metadata chunk into that. And, trivial to ignore or blindly carry it along if your software doesn’t specifically support it.

It's that last statement that makes it completely impractical. There isn't even a de facto standard for metadata with wav files. Most players/software don't even bother at all. FLAC pretty firmly settled on the ogginfo format and literally everything that supports FLACs use that same metadata format.

Arguably there doesn't need to be a de facto standard, because there's a de jure one: RIFF INFO.

But anyway, if you're going to do WAV tagging (and remember software support remains poor) most people are using ID3.

Re: FLAC 1.3.4

#110

Post by gugagore »

corysama wrote: post #2

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…

I'd argue (I think many would) that FLAC is substantially less complicated than MP3. Perceptual compression, the frequency domain, and things like the FFT are more complicated in implementation and in the math than Run-Length, residual / delta encoding, linear predictive coding. And perceptual compression schemes use both "classes" of compression tools anyway (broadly speaking).
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