Ripped audio track using WMA lossless codec on Windows 7 generates bigger file as compared to Vista


Symptoms


Consider the following scenario:
  • You are ripping a CD with Windows Media Player.
  • You are compressing the output audio file with the Windows Media Audio Lossless codec.
  • You compare the output file size of a file ripped on Windows Vista with the same file from the same CD ripped on Windows 7.
The WMA file generated by Windows Media Player 12 on Windows 7 will be silghtly larger (5-10%) as compared with the file generated from same audio track on Windows Vista.

Cause


This is due to the addition of extra information in each packet of audio data to make it compatible with older versions of WMA.

Resolution


For compatibility reasons this behavior is by design.

More Information


The audio data ripped using the two different operating systems is lossless. To ensure that the WMA file generated on Windows 7 and Windows Vista are same, you can perform the following:

1. Rip an audio track on Windows 7 using Windows Media Player 12 with format set to 'Windows Media Audio lossless'.
2. Rip the same audio track on Windows Vista using Windows Media Player 11 with format set to 'Windows Media Audio lossless'.
3. Convert the two WMA files generated by the two different operating systems to uncompressed PCM (WAV files) using wmal2pcm.exe.
4. The tool wmal2pcm.exe can be downloaded from following link:
http://www.microsoft.com/downloads/details.aspx?FamilyID=0AF5CE7A-50E9-4FF0-A687-E1F7D231F15E&displaylang=en&displaylang=en
5. Two WAV file will be of same size.