128kbps Extension Test - OPEN
Reply #105 – 2003-07-25 12:01:08
I noticed that, on some files, bitrate goes very high, nearing 200kbps sometimes. Is that right? i wouldnt write it that way as it will make people think that there are many files which are around 200, which isnt the case i wouldnt write 200kbps also, i would only write: "I noticed that, on some files, bitrate can go up pretty high. Is that right?"Yes, and that's the beauty of VBR encoding. It will simply ignore bitrate limitations (whenever possible), using as much bits as needed to encode a problematic sample. i wouldnt write that, as talking about that is "beautifull" that codecs ignore bitrate goals (whenever possible) isnt really an argument against people who claim that the vbr codecs "are cheating" imho Although that raises issues of fairness, it's the best way to compare modern codecs that shine the most in VBR mode, like Musepack and Vorbis. Trying to force a VBR setting to match as best as possible a desired bitrate, although fairer, is far from the usual practice of audio encoding, where it's more usual that an user just stick to a quality setting, not caring much about a specific bitrate 1) now this sounds like you think for yourself, that the test is unfair, but also that it has to be unfair as the vbr codecs "shine the most in VBR mode". this is also no argument against people claiming imho 2) i wouldnt tell the reader about his behaviour as everybody behaves different (for example i think that the usual practice in audio encoding for the masses is that people care to stay around a specific bitrate on the long run)quality settings for each codec were chosen because they average to 128kbps over a number of encoded albums. It would be unfair to tie the hands of VBR codecs and punish them for being smart about where to spend what turns out to be the same number of bits over the long run. now this is the most important part! and the only part which should be mentioned on the homepage imho! as it says that the vbr codecs will reach, with this settings, normally the average of 128kbps!!! that's the argument that counts (no need to talk about fairness or user behaviour or the beauty of vbr codecs) like what gabriel wrote:What is important is that the overall bitrate for overall music, using an encoder setting, would be 128kbps on average. If the average bitrate of those test samples for a specific codec is 180kbps, it is still fair is the overall bitrate for overall music is 128kbps. What a user wants is 128kbps as an overall. A user does not care if 10 seconds of his track are encoded using 250kbps while the next 10 seconds are encoded using 90kbps, as long as overall it is still 128kbps. sorry for my bad english