When a certain file (mp4, flv, etc) has a 95 kbps audio bitrate – does it make sense outputing to a higher bitrate when converting to mp3 or other format (be it lossy or not)?
Would this result in higher audio quality or just in a bigger file?
Edits after a lot of answers+comments:
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I am not talking about the output having better quality than the input: obviously, that is not possible. (Except for going from a lossless format to the original wave.) I am talking whether an output with a higher bitrate than the input will have a better quality than it might otherwise have.
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please consider that I am aware that converting between lossy formats is not recommendable. Only that in some cases an original cd/wave may be unavailable. The question is just about the usefulness of optionally increasing the bitrate when converting.
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maybe a sub-question is useful: is the answer dependent on the type of the output file (lossless or lossy)?
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the most voted two answers below (this and this) seem to say different things, namely, the later says that Bitrates are not directly comparable and if the original audio is in a more efficient format, then the output (less efficient) audio should have a somewhat superior bitrate (the same idea here and here) – but while the less efficient is mp3, I am not sure which exactly are the more efficient formats. (is it aac?) (– And in general the answers seem to fall in one of the two positions represented by the most voted answers.)
Best Answer
Yes, it might actually make sense if you are being forced to change formats.
If you have a file with 95kbps in a highly efficient format, to retain the same quality, a relatively inefficient format as mp3 needs a higher bitrate.
Of course you will never get anything back that was lost in the first place. On the contrary, encoding as mp3 will reduce the quality further. Every lossy format uses other means to reduce the amount of data that is stored, by (simplified) throwing away "unneeded" parts of the data. Round trip through a bunch of different formats and there won't be much left ...
So if you want to stay as close a possible to the quality your file has now, you should chose a higher bitrate. 320kbps are probably wasted space, but for mp3 something in the order between 128 and 192 is needed to maintain - or at least come close to - the quality of a more efficient 95kbps file.