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by shdh 897 days ago
> FLAC works by running a lossy compression pass, and then LZ encoding the residual.

Since when does FLAC run a lossy pass? You can recover the original soundwave from a FLAC file, you can't do the same with an MP3.

I'm pretty sure FLAC does not run a lossy compression pass.

Flickering textures in game engines are likely due to z-fighting, unless you're referring to some other type of flickering.

If you're looking to preserving as much detail as possible from your masters then floating points make sense. But its really overkill.
2 comments
adastra22 897 days ago
> The FLAC encoding algorithm consists of multiple stages. In the first stage, the input audio is split into blocks. If the audio contains multiple channels, each channel is encoded separately as a subblock. The encoder then tries to find a good mathematical approximation of the block, either by fitting a simple polynomial, or through general linear predictive coding. A description of the approximation, which is only a few bytes in length, is then written. Finally, the difference between the approximation and the input, called residual, is encoded using Rice coding.

Linear predictor is a form of lossy encoding.

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shdh 892 days ago
LPC is lossy, but FLAC maintains enough information to be able to reproduce the original data. Therefore its lossless even though LPC is a part of the compression.
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joshspankit 897 days ago
Yes exactly. What you’re saying lines up with what I’ve learned through experience.

> If you're looking to preserving as much detail as possible from your masters then floating points make sense.

I’ve been searching for hours and gotten nothing more than the classic floats vs ints handwaving. Can you explain what you know about why using floats preserves detail?

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adastra22 897 days ago
Do you actually have experience writing a FLAC encoder/decoder? I do. Go read the format specification. There is a lossy compression pass, then it uses a general compressor on the residual after you subtract out the lossy signal. The two combined allow you to reconstruct the original signal losslessly.
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