MPEG Audio - Wikipedia bias?
Reply #2 – 2014-02-16 12:56:39
Indeed. Thanks for bringing this up, I totally forgot about this! Some nonsense or vastly outdated information (emphasis mine):Layer II, Quality: The article says, "MP2 remains a favoured lossy audio coding standard due to its particularly high audio coding performances on important audio material such as castanet, symphonic orchestra, male and female voices and particularly complex and high energy transients (impulses) like percussive sounds: triangle, glockenspiel and audience applause [20 ]." although such supposedly important audio material isn't mentioned anywhere in that reference [20 ]. Layer II, Quality: MP2 is said "to offer transparent audio compression ... using the earliest reference implementation (more recent encoders should presumably perform even better ) ..." but then elaborates on AAC - a much more complicated codec - performing quite badly on applause signals in 1998, making it sound like this were a limitation of the AAC standard (which it clearly isn't, as can be shown with more recent encoders). Layer III/MP3, Technical Details: After describing the block switching to shorter transforms, it is said, "And yet in choosing a fairly small window size to make MP3's temporal response adequate enough to avoid the most serious artifacts, MP3 becomes much less efficient in frequency domain compression of stationary, tonal components ." This is purely academic, because who would use short blocks - which are meant for transients - on stationary sounds? In the following paragraph starting with "Being forced to use a hybrid ..." it is clear that the author hasn't understood at all how MP3's aliasing cancellation (Edit: actually, it's a reduction) stage works. "... produces frequency domain energy"? "... pushed to the top of the frequency range "?? Of course, MP3's design is bad, but how about the inherent aliasing in MP2 - which cannot be cancelled reduced prior to spectrum quantization - and, consequently, MP2's bad performance on stationary tonal material? That isn't mentioned anywhere. Layer III/MP3, Quality: oh my, every single one of the first 7 sentences (except the 5th one) needs a "Citation needed" mark! It already starts with the totally out-of-context first sentence, "These technical limitations inherently prevent MP3 from providing critically transparent quality at any bitrate". The previous text actually noted some advantages of MP3... Chris