• black0ut@pawb.socialOP
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    6 days ago

    When we talk about lossless in the audio encoding world, we aren’t comparing directly with the analog wave, as there will always be loss when storing an analog signal in a digital machine. Lossless formats are compared to pure PCM, which is the uncompressed way of representing a waveform in bits.

    With audio, every step you take to transform it, capture it, move it or store it, even while working with the analog waveform, degrades it. Even by picking it up with a microphone you’re already degrading the waveform. However, generally, the official release CDs or WebDLs are considered the original, lossless, master file. Everything that manages to keep that exact waveform is lossless (FLAC, AIFF, WAV, ALAC…), and everything that distorts it further is considered lossy (MP3, AAC, OPUS…).

    Additionally, a “bad transcode” (which is a transcode that involves lossy formats somewhere that isn’t the last step) is also considered lossy, for obvious reason. Transcoding FLAC to MP3 to WAV stores the exact same waveform that MP3 made, as it is the lowest common denominator, even though the audio is stored as WAV in its final form.

    Transcoding between lossy formats also loses more data, even if the final lossy format can store more bits or is more accurate than the original. This is one of the main problems with lossy codecs. MP3 192kbps to MP3 320kbps will lose information, just like MP3 to AAC. That’s why, normally, we use a lossless file and transcode it to every lossy format (FLAC to MP3, then FLAC to AAC…). This way you’re not losing more than what the lossy format already loses.

    • Aceticon@lemmy.dbzer0.com
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      6 days ago

      My point being that unlike the misunderstanding (or maybe just mis-explanation) of many here, even a digital audio format which is technically named “lossless” still has losses compared to the analog original and there is no way around it (you can reduce the losses with a higher sampling rate and more bits per sample, but never eliminate it because the conversion to digital is a quantization of an infinite precision input).

      “Losslessness” in a digital audio stream is about the integrity of the digital data itself, not about the digital audio stream being a perfect reproduction of the original soundwaves. With my mobile phone I can produce at home a 16 bit PCM @ 44.7 kHz (same quality as a CD) recording of the ambient sounds and if I store it as an uncompressed raw PCM file (or a Wav file, which is the same data plus some headers for ease of use) it’s technically deemed “lossless” whilst being a shit reproduction of the ambient sounds at my place because the capture process distorted the signal (shitty shit small microphone) and lost information (the quantization by the ADC in the mobile phone, even if it’s a good one, which is doubtful).

      So maybe, just maybe, some “audiophiles” do notice the difference. I don’t really know for sure but I certainly won’t dismiss their point about the imperfect results of the end-to-process, with the argument that because after digitalization the digital audio data has been kept stored in a lossless format like FLAC or even raw PCM, then the whole thing is lossless.

      One of my backgrounds is Digital Systems in Electronics Engineering, which means I also got to learn (way back in the days of CDs) how the whole process end to end works and why, so most of the comments here talking about the full end-to-end audio capture and reproduction process (which is what a non-techie “audiophile” would be commenting about) not being lossy because the digital audio data handling is “lossless”, just sounds to me like the Dunning-Krugger Effect in action.

      People here are being confidently incorrect about the confident incorrection of some guy on the Internet, which is pretty ironic.

      PS: Note that with high enough sampling rates and bits per sample you can make it so precise that the quantization error is smaller that the actual noise in the original analog input, which de facto is equivalent to no losses in the amplitude domain and so far into the high frequencies in the time domain that no human could possibly hear it, and if the resulting data is stored in a lossless format you could claim that the end-to-end process is lossless (well, ish - the capture of the audio itself into an analog signal itself has distortions and introduces errors, as does the reproduction at the other end), but that’s something quite different from claiming that merely because the audio data is stored in a “lossless” format it yields a signal as good as the original.

      • black0ut@pawb.socialOP
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        6 days ago

        What I meant is yeah, you are right about that, but no, lossless formats aren’t called lossless because they don’t lose anything to the original, they’re called lossless because, after compressing and decompressing, you get the exact same file that you initially compressed.

        Another commenter on this post explained it really well.

        • Aceticon@lemmy.dbzer0.com
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          6 days ago

          They’re deemed “lossless” because there are no data losses - the word actually comes from the broader domain of data handling, specifically Compression were for certain things - like images, audio and video - there are compression algorithms that lose some information (lossy) and those which don’t (lossless), for example JPEG vs PNG.

          However data integrity is not at all what your average “audiophile” would be talking about when they say there are audio losses, so when commenting on what an non-techie “audiophile” wrote people here used that “losslessness” from the data domain to make claims in a context which is broader that merelly the area were the problem of data integrity applies and were it’s insuficient to disprove the claims of said “audiophile”.

          • black0ut@pawb.socialOP
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            6 days ago

            By your definition, PNG isn’t lossless because it’s not an exact representation of every single photon of a picture that was taken. You’d need infinity pixels in order to be completely faithful to the “analog” thing that you’re trying to picture, in the same way you’d need infinity points to completely translate an analog wave to digital.

            When you compress anything with FLAC, you will get the exact same thing you compressed out, so there is no data loss.

            Of course, that wave which you compress will not be faithful to the analog thing, but that’s just a limitation of digital computers.

            • Krudler@lemmy.world
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              5 days ago

              Not really infinite points since energy is quantized. In a crazy particle physics sense analogue data is effectively the same as digital, when resolutions match.

              edit: Downvoting doesn’t change your mistaken belief that it’s possible to infinitely resolve analog light. You can’t. Look up the Planck length and learn about photons. It is possible to have a digital storage container that is of higher resolution than the wave data it holds.

            • Aceticon@lemmy.dbzer0.com
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              5 days ago

              A PNG is indeed an imperfect representation of reality. Are you claiming that the lossness in the data domain of the compression algorithm in a PNG means its contents are a perfect representation of reality?!

              (Funnilly enough, the imperfections in the data contained on a PNG are noticeable for some and the lower the “sampling rate” - i.e. number of pixels, bits per pixel - the easier it is to spot, same as audio)

              As I’ve been trying to explain in my last posts, a non-Techie “audophile” when they claim FLAC is not lossless aren’t likely to be talking about it’s technical characteristics in the data domain (i.e. that data that you take out of a FLAC file is exactly the same as it goes in) but that its contents don’t sound the same as the original performance (or, most likely, a recording made via an entirelly analog pathway, such as in an LP).

              Is it really that hard to grasp the concept that the word “lossless” means different things for a Technical person with a background in digital audio processing and a non-Technical person who simply compares the results of a full analog recording and reproduction pathway with those of a digital one which include a FLAC file and spots the differences?

              This feels like me trying to explain to Junior Developers that the Users are indeed right and so are the Developers - they’re just reading different meanings for the same word and, no, you can’t expect non-Techie people to know the ins and outs of Technical terms and no they’re not lusers because of it. Maybe the “audiphile” was indeed wrong and hence “Confidently Incorrect”, but maybe he was just using lossless in a broader sense of “nothing lost” like a normal person does, whilst the other one was using the technical meaning of it (no data loss) so they were talking past each other - that snippet is too short to make a call on that.

              So yeah, I stand by my point that this is the kind of Dunning-Krugger shit junior techies put out before they learn that most people don’t have the very same strictly defined technical terms on their minds as the junior techies do.

              • Krudler@lemmy.world
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                5 days ago

                You really do not understand the subject you’re bloviating about. Consider stopping now.

          • Krudler@lemmy.world
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            6 days ago

            Fake it 'till you make it is not applicable to scientific or technical discussions.

            • Aceticon@lemmy.dbzer0.com
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              5 days ago

              Nice content-free slogan.

              I’m not a Sound Engineer, I’m an Electronics Engineer - we’re the ones who had to find the right balance between fidelity, bit error rates, data rates and even circuit price when designing the digital audio sampling systems that capture from the analog world the digital data which the Sound Engineers use to work their magic: so I’m quite familiar with the limits of analog to digital conversion and that’s what I’m pointing out.

              As it so happens I also took Compression and Cryptography in my degree and am quite familiar with where the term “lossless” comes from, especially since I took that elective at the time when the first lossy compression algorithms were starting to come out (specifically wavelet encoding as used in JPEG and MPEG) so people had to start talking about “lossless” compression algorithms with regards to the kind of algorithms what until then had just been called compression algorithms (because until then there were no compression algorithms with loss since the idea of losing anything when compressing data was considered crazy until it turns out you could do it and save tons of space if it was for stuff like image and audio because of the limitations of human senses - essentially in the specific case of things meant to be received by human senses, if you could deceive the human senses then the loss was acceptable, whilst in a general data sense losing data in compression was unacceptable).

              My expertise is even higher up the Tech stack than the people who to me sound like Junior Devs making fun of lusers because they were using technical terms to mean something else, even while the Junior Devs themselves have yet to learn enough to understand the scope of usage and full implications for those technical terms (or the simple reality that non-Techies don’t have the same interpretation of technical terms as domain experts and instead interprete those things by analogy)

              • Krudler@lemmy.world
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                5 days ago

                STFU and stop dropping your resume. Nobody gives a shit, and I can tell you I’m FAR more knowledgeable than you.

                You literally don’t understand the difference between a sensor, data, compression, or anything else. You don’t understand energy, physics, or the underlying concepts.

                You are not as informed as you personally believe.

                Literally STFU

                • Aceticon@lemmy.dbzer0.com
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                  5 days ago

                  Clearly my point about this being like Junior Devs thinking they know better that the “lusers” whilst not knowing enough to understand the limits of their knowledge hit the mark and hurt.

                  It’s hilarious that you think a background in game making (by the way, love that hypocrisy of yours of criticizing me for pointing out my background whilst you often do exactly the same on your posts) qualifies you to understand things like the error rates in the time and amplitude domains inherent to the sampling and quantization process which is Analog-to-Digital conversion “FAR” better than a Digital Systems Electronics Engineering Degree - you are literally the User from the point of view of a Digital Systems EE.

                  Then the mention of Physics too was just delicious because I also have part of a Physics degree that I took before changing to EE half way in my degree, so I studied it at Uni level just about long enough to go all the way to Quantum Mechanics which is a teensy weensy bit more advanced than just “energy” (and then, funnily enough, a great deal of EE was also about “energy”).

                  Oh, and by the way, if you think others will Shut The Fuck Up just because you tell them to, you’re in for a big disappointment.