![]() The Encoder class is a Stream subclass that accepts raw PCM data written to The MP3 file is determined (usually right at the beginning). It also emits a "format" event when the format of The Decoder class is a Stream subclass that accepts MP3 data written to it,Īnd outputs raw PCM data. See the examples directory for some more example code. pipe ( encoder ) // the generated MP3 file gets piped to stdout encoder. Encoder ( ) // raw PCM data from stdin gets piped into the encoder process. Can you guarantee your decoder and/or player won't be doing output dithering or some other funkiness? Headphone drivers usually do far more to alter the output signal than any particular codec choice.Var lame = require ( 'lame' ) // create the Encoder instance var encoder = new lame. Nothing including the signal chain is usually perfect. Even my old Rockboxed iRiver and my car (via A2DP) merrily decode AACs with higher quality and lower file sizes. AAC improves upon the encoding methods used by MP3. Vorbis and MP3's encoding methods and acoustic models are rather dated and AAC is the new king of cross-platform compatibility. This may be an interesting read if you're interested in the technical capabilities of FLAC, AAC and MP3 at various bit rates when pushed to extremes with test waveforms. AoTuV), I find them more transparent in the time domain and often more accurate at reproduction than MP3 (even with Vorbis's acknowledged pre-echo quirkiness). Personally I now encode as AAC-LC (at least 256 kbps) or one of the tuned Vorbis (e.g. ![]() Over time I came to realise - if I feed foo_abx with a 320 and a V0 VBR, can I tell them apart? If not, I always pick V0. Having done a lot of blind comparisons over the past few years, LAME VBR wins over just about everything. I would personally use -V 0 instead of -b 320 unless you need CBR due to decoder limitations. If you manually encode from FLAC using the latest LAME and specify -b 320 or -V 0 then compare, what do you see?.What command switches is it indicating it's using to encode the 320s?.Which build of LAME are you using, did it install one with? I'd upgrade to the latest version separately.IMO the benefit obtained due to the ear's response curves, and the importance of preserving accuracy of spectral content in that key frequency band, is going to outweigh maxing out the quality of all bands (including the >= 16 kHz band), and possibly introducing frequency artifacts not present in the source audio due to disabling a beneficial feature of the MP3 encoder. You can go for the ' APE' preset if you want to 'lock off' all of the scale factors at the same quality, but I wouldn't. Marc W's prior explanation of the Spectral Reproduction content answers your question, and is an excellent read. The encoder model decides this, and it's in part due to scaling factors and the bands into which the source signal is divided prior to being processed and encoded. What you're seeing is the visual representation of quantised high frequency content not being encoded to save on arguably unneeded bits. ![]() MP3 encoding employs psychoacoustic techniques like masking (in both frequency and time domain) to reduce the complexity of encoded audio whilst not perceptually sacrificing quality. ![]()
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