lossless audio data different when read on 2 different machine Matthew Shaver <yumecorp[ at ]newsgroup.nospam> 6/1/2007 12:22:08 AM When I play a WMV file with a lossless audio track on two different machines when I look at the data in a Windows Media Player Audio DSP Plugin I see slightly different data. So does lossless not mean I get the exact same data? Are there different versions of the lossless codec which produce different data when decompressing? Thanks, Matt.

Re: lossless audio data different when read on 2 different machine "Chris P." <msdn[ at ]chrisnet.net> 6/1/2007 5:01:05 PM On Thu, 31 May 2007 17:22:08 -0700, Matthew Shaver wrote: [Quoted Text] > When I play a WMV file with a lossless audio track on two different > machines when I look at the data in a Windows Media Player Audio DSP > Plugin I see slightly different data. So does lossless not mean I get > the exact same data? Are there different versions of the lossless codec > which produce different data when decompressing? It's probably not the decoder but another filter that is inserted before your DSP plugin. The decoder may also output in different formats depending on what the connecting filter requests, e.g. 24-bit vs 16-bit. If the format is the same then it's likely other filters interfering. -- http://www.chrisnet.net/code.htm [MS MVP for DirectShow / MediaFoundation]

Re: lossless audio data different when read on 2 different machine Matthew Shaver <yumecorp[ at ]newsgroup.nospam> 6/1/2007 6:44:57 PM Chris P. wrote: [Quoted Text] > On Thu, 31 May 2007 17:22:08 -0700, Matthew Shaver wrote: > >> When I play a WMV file with a lossless audio track on two different >> machines when I look at the data in a Windows Media Player Audio DSP >> Plugin I see slightly different data. So does lossless not mean I get >> the exact same data? Are there different versions of the lossless codec >> which produce different data when decompressing? > > It's probably not the decoder but another filter that is inserted before > your DSP plugin. The decoder may also output in different formats > depending on what the connecting filter requests, e.g. 24-bit vs 16-bit. > If the format is the same then it's likely other filters interfering. > There are no other DSP plugins registered on either system. Is there any other type of filter you are referring to? Thanks, Matt.

Re: lossless audio data different when read on 2 different machine "Chris P." <msdn[ at ]chrisnet.net> 6/2/2007 3:11:28 AM On Fri, 01 Jun 2007 11:44:57 -0700, Matthew Shaver wrote: [Quoted Text] > There are no other DSP plugins registered on either system. Is there any > other type of filter you are referring to? WMP itself has other filters in the playback graph to control audio effects such as the graphic equalizer. Even when these effects are turned off the audio passes through these filters. Technically the filter should be in bypass mode and pass through unaltered but without knowing the internals of each filter you can't be sure. -- http://www.chrisnet.net/code.htm [MS MVP for DirectShow / MediaFoundation]

Re: lossless audio data different when read on 2 different machine Matthew Shaver <yumecorp[ at ]newsgroup.nospam> 6/4/2007 10:50:30 PM Chris P. wrote: [Quoted Text] > On Fri, 01 Jun 2007 11:44:57 -0700, Matthew Shaver wrote: > >> There are no other DSP plugins registered on either system. Is there any >> other type of filter you are referring to? > > WMP itself has other filters in the playback graph to control audio effects > such as the graphic equalizer. Even when these effects are turned off the > audio passes through these filters. Technically the filter should be in > bypass mode and pass through unaltered but without knowing the internals of > each filter you can't be sure. > Found the equalizer turned on but still have the problem after turning it off.

Re: lossless audio data different when read on 2 different machine Matthew Shaver <yumecorp[ at ]newsgroup.nospam> 6/4/2007 10:54:18 PM Chris P. wrote: [Quoted Text] > On Fri, 01 Jun 2007 11:44:57 -0700, Matthew Shaver wrote: > >> There are no other DSP plugins registered on either system. Is there any >> other type of filter you are referring to? > > WMP itself has other filters in the playback graph to control audio effects > such as the graphic equalizer. Even when these effects are turned off the > audio passes through these filters. Technically the filter should be in > bypass mode and pass through unaltered but without knowing the internals of > each filter you can't be sure. > Found the equalizer turned on but still have the problem after turning it off.

Re: lossless audio data different when read on 2 different machine Matthew Shaver <yumecorp[ at ]newsgroup.nospam> 6/4/2007 10:54:35 PM Chris P. wrote: [Quoted Text] > On Fri, 01 Jun 2007 11:44:57 -0700, Matthew Shaver wrote: > >> There are no other DSP plugins registered on either system. Is there any >> other type of filter you are referring to? > > WMP itself has other filters in the playback graph to control audio effects > such as the graphic equalizer. Even when these effects are turned off the > audio passes through these filters. Technically the filter should be in > bypass mode and pass through unaltered but without knowing the internals of > each filter you can't be sure. > Found the equalizer turned on but still have the problem after turning it off.

Re: lossless audio data different when read on 2 different machine "Chris P." <msdn[ at ]chrisnet.net> 6/5/2007 2:14:16 AM On Mon, 04 Jun 2007 15:54:35 -0700, Matthew Shaver wrote: [Quoted Text] > Found the equalizer turned on but still have the problem after turning > it off. Any possibility of testing a 3rd PC? It might point to the odd man out. -- http://www.chrisnet.net/code.htm [MS MVP for DirectShow / MediaFoundation]