View Single Post
Old 7th June 2006, 08:33   #1  |  Link
3dsnar
Registered User
 
3dsnar's Avatar
 
Join Date: Dec 2005
Location: Proxima Centauri
Posts: 315
Dolby Pro Logic II encoding test (90° vs 180° phase shift)

Here are two clips,
http://forum.videohelp.com/images/gu...165/180vs90.7z

And the reference (original 6 channel input) clip.
http://forum.videohelp.com/images/gu...helem_6chnl.7z

Each downmixed with:
Lt = FL{0°} + 0.7071 C{0°} + 0.7071 LFE{0°} + 0.866 SL{180°} + 0.5 SR{180°}
Rt = FR{0°} + 0.7071 C{0°} + 0.7071 LFE{0°} + 0.5 SL{0°} + 0.866 SR{0°}
and
Lt = FL{0°} + 0.7071 C{0°} + 0.7071 LFE{0°} + 0.866 SL{90°} + 0.5 SR{-90°}
Rt = FR{0°} + 0.7071 C{0°} + 0.7071 LFE{0°} + 0.5 SL{-90°} + 0.866 SR{+90°}

Please test them with your dolby certified decoders
and decide which ones sounds better (eg. A vs B version) with reference to the original sound.
The poll question is related to fifthelem_A.mp3 and fifthelem_B.mp3,
while speech_A.mp3 and speech_B.mp3 should sound identical
(to see that both downmixing methods are compatible with DPLII decoders)
__________________
Aud-X MP3 5.1 Format

Last edited by 3dsnar; 7th June 2006 at 09:40.
3dsnar is offline   Reply With Quote