>>>>> Can the conversion to S24_3LE be lossy? >>>>> >>>>> - Grant >>>>> >>>> >>>> The conversion is to 24 bits. So, if the conversion is from lower >>>> numbers >>>> of bits,it's lossless, if from higher - it's lossy. >>>> >>>> Regards, >>>> Sergei. >>> >>> I think mpd outputs in a 32-bit format. If plughw converts that >>> 32-bit format to S24_3LE, will it be lossy compared to the original >>> audio which is 16-bit or 24-bit? Or would mpd pad the 16-bit or >>> 24-bit audio with zeros, and then plughw strips some of the zeros off? >>> >>> - Grant >>> >> >> MPD may use as many bits as it likes, but are the bits present in the >> original music file ? AFAIK not, i.e. the added buts are zeros and the >> stripped bits are zeros. > > It depends on how the bits are added. Usually the bits added are low order > bits-- this is to ensure that roundoff error does not keep adding noise to > the > system, and to use a common calculational track no matter wha the input, and > so they use a size that is bigger then any possible. On the other hand they > may want extra headroom and add the padding at the high end instead. Now, if > the program were at all competent, they would make sure that the output was > the same as the input (ie do the stripping down internally) to make sure > that > the problems feared would not occur. But then again, who knows if the > authors > were competent. > > Anyway, you could tell by running the input and output through sox and > seeing > if the amplitude is the same. If it is, mpd behaves properly. If it is not, > then not. Just thought I'd mention that mpd in git now outputs S24_3LE. - Grant ------------------------------------------------------------------------------ Throughout its 18-year history, RSA Conference consistently attracts the world's best and brightest in the field, creating opportunities for Conference attendees to learn about information security's most important issues through interactions with peers, luminaries and emerging and established companies. http://p.sf.net/sfu/rsaconf-dev2dev _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
