Originally posted by Ivan Dimkovic MP3 has only one 'scale factor' (frequency band) for the range of 16-22.05 kHz (if 44.1 kHz sampling rate is used)
Originally posted by Ivan Dimkovic If I remember correctly (and Frank will correct me if I am wrong Layers I and II only had Intensity Stereo (IS) and normal stereo (LR) modes, switchable on a frame basis - ie. one frame could be either IS or LR
Originally posted by Frank Klemm MP3 has NO 'scale factor' for the range from 16-22.05 kHz (fs=44.1 kHz).To be able to store 16-22.05 kHz you must pump a LOT of bits into the region0...16 kHz. You must pump so much bits into the low frequency region, that thiswould increase bitrate by 100...600 kbps. So you can only do this for a smallamount of frames.Frames with contens above 16 kHz must be quantized fully different from other frames if you don't want to add only noise to sfb21.
Originally posted by 2Bdecided That bascially means that JS should not be used for high quality in MPEG layer 2?
Originally posted by Slo Mo Snail AFAIK MPEG-I layer 2 wasn't even designed for high quality
Originally posted by takehiro Quite hacky fix, but we can encode the sfb21 without such big bit consumption.see my post to the lame-dev about "pseudo substep quantization".The point is "trancation". Using trancation is virtually "minus" scalefactor. The global gain should be pump up to save the noise in sfb21. But using trancation in 0-16kHz region will reduce the bitrate.
Originally posted by rjamorim Heh, it really sucks at low bitrates, but can beat any MP3 implementation out there at high bitrates using the problem cases (castanets, fatboy...)
Originally posted by JohnV The key word here is "can". It can also be clearly worse than what comes out from an MP3 encoder. That's because MP3 encoders' (at least Lame,FhG) psychoacoustics is often more tweaked than MP2 encoder's.