3 ms·

Does this work if the encoders are different? Are encoders aware that you are transcoding rather than working on raw waveform data? Presumably if working on wa

Does this work if the encoders are different? Are encoders aware that you are transcoding rather than working on raw waveform data? Presumably if working on waveform data the higher bitrates will seek to maintain the artifacts due to the earlier transcoding. Can one rely this much on the behaviour of an encoder?

bheadmaster 2y ago
> Does this work if the encoders are different? I have no idea, honestly. I've tested my script (from a sibling comment of yours) with twolame [0] encoder, and I don't know if the results are good enough to indicate 64kbps true bitrate: user@host:~/temp$ ./main.sh 36-twolame-reencoded.mp3 320: 0.032303 256: 0.045563 224: 0.059769 192: 0.074631 160: 0.204269 128: 0.229187 112: 0.309540 96: 0.302414 80: 0.310181 64: 0.367279 56: 1.133713 48: 1.106262 40: 0.444473 32: 1.030777 [0] https://www.twolame.org/ https://www.twolame.org/
Joel_Mckay 2y ago
Not all mp3 codecs are the same, and some include a feature called perceptual compression. Thus, the predominate features of the audio one actually hears are preserved over high-frequency overtones most people find unpleasant. Thus, the self-similarity of the small file is improved, while the perceived sound quality is better at lower bit-rates (note not all psychoacoustic models are the same). This is why some encoders sound like garbage even at relatively high encoded quality levels. Lets be clear, most people can't hear the difference (e.x. digital synth music makes smaller files with duplicate audio), and others simply adapt to poor sound quality given they hit the $2.34 hardware mixer chip interpolation limitations long before the audio codecs limits (e.x. Bluetooth can be really iffy). Don't worry about it, and maybe pick up a stringed instrument if you want a quality experience =3

bheadmaster 2y ago

> Does this work if the encoders are different? I have no idea, honestly. I've tested my script (from a sibling comment of yours) with twolame [0] encoder, and I don't know if the results are good enough to indicate 64kbps true bitrate: user@host:~/temp$ ./main.sh 36-twolame-reencoded.mp3 320: 0.032303 256: 0.045563 224: 0.059769 192: 0.074631 160: 0.204269 128: 0.229187 112: 0.309540 96: 0.302414 80: 0.310181 64: 0.367279 56: 1.133713 48: 1.106262 40: 0.444473 32: 1.030777 [0] https://www.twolame.org/ https://www.twolame.org/

Joel_Mckay 2y ago

Not all mp3 codecs are the same, and some include a feature called perceptual compression. Thus, the predominate features of the audio one actually hears are preserved over high-frequency overtones most people find unpleasant. Thus, the self-similarity of the small file is improved, while the perceived sound quality is better at lower bit-rates (note not all psychoacoustic models are the same). This is why some encoders sound like garbage even at relatively high encoded quality levels. Lets be clear, most people can't hear the difference (e.x. digital synth music makes smaller files with duplicate audio), and others simply adapt to poor sound quality given they hit the $2.34 hardware mixer chip interpolation limitations long before the audio codecs limits (e.x. Bluetooth can be really iffy). Don't worry about it, and maybe pick up a stringed instrument if you want a quality experience =3