so.... i have a file that is 128 aac, i have converted it to 320 aac, and put it into fakin' the funk, but it says that, yes it is upscaled of course, but it also says that the effective bitrate is 192 kpbs, the same happened with mp3. i have seen the spectrum with the frequency curve and it says that 128 is near 16k khz but that is wrong, because in most cases an aac 128 cuts at 18 khz, while the spectrume curve says that at 18 khz is 192 kbps, but as i have said and as the original file (128 aac) says, the 128 aac cuts at 18 khz... so the effective bitrate that for fakin' the funk is 192 kbps should be 128 of course, since i have upscaled an 128 aac file to 320 aac. I hope you guys have understand what im trying to say.
Original file 128 aac
File upscaled to 320 kbps ( the effective bitrate for fakin' the funk is 192 kbps but ofc should be 128)
I don't know how much it actually analyzes a track, and from what the author himself said on another thread, the program merely checks for drops, which is from what I have discussed with others isn't a sure-fire way to indicate the actual quality of a track. Heck, I post a few examples myself on another person's thread ("false results?") with 3 various examples on incorrect the estimates are.
But I think the difference in your example is that a 128kb AAC is not the same as 128kb MP3 and thus can create different results
yes, besides, often a lot of tracks lack of high frequencies... so for example a 320 or a flac file could be stuck at 18khz or 19khz.... the program would automatically say that the effective bitrate is not 320 but of course is wrong.
its pretty normal that 320 mp3 fill till 22 khz, its not normal that for FTF the max of 320 mp3 is 20 khz.... almost never the max khz of a 320 mp3 file is 20 khz, and as i said earlier a lot of times a 320 mp3 file could be stuck at 18 khz and its a legit 320 mp3.... the effective bitrate is not 128 kpbs as FTF is saying.
I just think that its very difficult to judge the file based on the curve of frequencies because there are too many factors that have to be considered.
I mean.... i have installed FTF to see if an mp3 file is legit.... but if the algorithm is only based on a supposition based on the frequencies.... at this point i would use spek and thats it.