Is there any way to find actual bitrate?

Hi, I just wanted to know that if I have two files, file1 being 128kbit/s and file2 is just a conversion of file1 to 320kbit/s. Both are mp3s. Is there any way by which I can tell that the 320kbit/s file's acutal bitrate is 128kbit/s. Thanks

i think quality reduces or is the same as 128

What I meant was that I rip a track off a cd to a 128k mp3 file and then I re-encode that mp3 file from 128K to 320K. The quality of the 2 will obviously be the same but is there any way I can tell from the 320k file that its bitrate is actually 128. EDIT Is there some software like encspot for other formats like aac and vorbis?

The 320kbps mp3 will be even worse than the 128kbps mp3, as transcoding will always give you worse quality. Anyway, there is no easy way of telling an mp3 is transcoded. The only real way is to listen very carefully and compare it to the original CD. 128kbps have a lowpass of about 16khz, so any frequencies higher than that are lost forever. So the 320kbps mp3 doesn't have these high frequencies either. So what might help is looking at the spectrum graph, that most (advanced) wav editors can display. If you see a cap at 16khz then it'll probably transcoded from a 128kbps. Now the problem with this method is that: 1) the original CD source might not have frequencies above 16khz. Probably older CDs or just badly mastered CDs. 2) you can disable the 16khz lowpass when encoding 128kbps, this will result in horrible overal sounding mp3, but in the frequency graph you will still show the high frequencies. So the graph doesn't say anything in this case.