Fernando Alberto Marengo Rodriguez
2011-May-16 20:51 UTC
[Flac] Is FLAC hardware independent?
Dear list, We are investigating about some state-of-the-art lossless audio codecs and their performance in terms of? rate and compression ratio. Therefore, it is very important to us to know whether a codec is hardware independent, i.e. if it produces the same output file regardless of the hardware. Could you please tell me whether FLAC is hardware independent? Thank you very much in advance. Kind regards, ? Fernando A. Marengo Rodriguez, PhD Acoustics and Electroacoustics Laboratory School of Electronic Engineering Faculty of Sciences, Engineering and Surveying National University of Rosario Rosario, Argentina -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.xiph.org/pipermail/flac/attachments/20110516/22b0f1a0/attachment.htm
Which "output file" are you referring to? Also, your question is incompletely specified, because you do not qualify whether the input is the same when you expect the output to be the same. When uncompressing, the final results are lossless, therefore it is hardware independent when you consider the total process. When compressing, the results depend upon the implementation. In this respect, the intermediate output file is both hardware dependent and version dependent. In other words, you can get a different output file size even on the same hardware. Perhaps there is a misunderstanding here, by trying to fit FLAC into the same criterion as lossy formats. Lossless formats do not have a fixed rate, nor do they have a fixed compression ratio. Lossy formats throw away information in order to achieve a desired rate or ratio, but lossless formats cannot throw away information and therefore cannot reach the same goal every time. Results vary greatly depending upon the input material and the implementation, which varies by version and hardware. Brian Willoughby Sound Consulting On May 16, 2011, at 13:51, Fernando Alberto Marengo Rodriguez wrote:> We are investigating about some state-of-the-art lossless audio > codecs and their performance in terms of rate and compression > ratio. Therefore, it is very important to us to know whether a > codec is hardware independent, i.e. if it produces the same output > file regardless of the hardware. Could you please tell me whether > FLAC is hardware independent? > Thank you very much in advance. > Kind regards,
Fernando Alberto Marengo Rodriguez
2011-May-17 20:43 UTC
[Flac] Is FLAC hardware independent?
Dear list,> Which "output file" are you referring to?? Also, your question isincompletely specified, because you do not qualify whether the input is the same when you expect the output to be the same. My question is the following: For any encoding option (e.g. -5, default), does the flac encoder produce the same byte-for-byte output regardless of the CPU? Regards, Fernando PS: Here is the answer of David Bryant, the developer of WavPack: "The WavPack codec is hardware independent; the standard "C" encoder will produce the same byte-for-byte output regardless of the CPU it is running on (assuming a properly working C compiler, of course)." -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.xiph.org/pipermail/flac/attachments/20110517/8af2ead9/attachment.htm