Guide: 2- to 5-channel upmix using Dolby Pro Logic II

[bleo]

This procedure is similar in purpose to GUIDE: Stereo to 5-Channel Surround but uses Dolby Pro Logic II upmixing.

You can upmix any 2-channel audio format as long as you have the appropriate DirectShow decoder filter installed.

Software required:
- InterVideo WinDVD (http://www.intervideo.com/)
- GraphEdit (http://www.doom9.org/Soft21/Audio/graphedit.rar)
- A hex editor e.g. XVI32 (http://www.chmaas.handshake.de/delph...vi32/xvi32.htm)

Procedure:
- In GraphEdit go to File > Render Media File... > Open your 2-channel audio file
- Delete the Default DirectSound Device filter
- Go to Graph > Insert Filters... > DirectShow Filters > InterVideo Audio Processor Fx > Insert Filter
- Also insert the WAV Dest filter and File writer filter with an output filename e.g. output.wav
- Connect the audio decoder to InterVideo Audio Processor Fx, then WAV Dest, then the File writer filter
- Right click the InterVideo Audio Processor Fx filter > Filter Properties... > 6 SPEAKER
- Go to InterVideo Container DMO > InterVideo EXP DMO > Append <---
- Click Play and then immediately click Stop to 'initialise' the filter
- Go back to Filter Properties > InterVideo EXP DMO tab > ProLogic2
- Click Play and wait until the button reactivates
- The output file has an incorrect 2-channel WaveFormatEx header!
- Use a hex editor to change:
- nChannels at 16 from 02 to 06
- nAvgBytesPerSec at 1C from 00 EE 02 to 00 CA 08 if your audio is 48 KHz, or from 10 B1 02 to 30 13 08 if it is 44.1 KHz
- nBlockAlign at 20 from 04 to 0C
- You now have a Dolby Pro Logic II upmixed 6-channel WAV file! (empty .1 channel)
- You can reencode it to AC3, AAC, Ogg Vorbis, RealAudio, DTS, WMA9Pro, et al, multi-channel formats using the appropriate programs

Let me know your feedback/problems! Good luck!

BeSplit:
- The demuxed mono output files also have incorrect WAV headers. Use your handy hex editor to change nBlockAlign at 20 from 06 to 02.
- The channel ordering is FL FR C LFE BL BR

WMA9Pro:
Requires WaveFormatExtensible header for direct loading of 6-channel WAV. Use your hex editor to change:
- riffSIZE at 4, add 0x16 to the DWORD here (note little-endian byte order)
- fmtSIZE at 10 from 12 to 28
- wFormatTag at 14 from 01 00 to FE FF
- cbSize at 24 from 00 to 16
- insert at 26, 10 00 3F 00 00 00 01 00 00 00 00 00 10 00 80 00 00 AA 00 38 9B 71

Notes:
- Feel free to tweak the settings on the InterVideo EXP DMO tab to your liking! In general, use Movie mode for DPL(2) encoded material and Music mode if not.
- InterVideo's filter seems to silence the first second of audio...
- Has anyone got a better solution to the WAV header hacking e.g. an automatic program or a better WAV wrapper?

Edit: argh! On closer inspection, there appears to be a bug in the CyberLink filter where it only does DPL ONE upmixing i.e., the surround channels are identical. Is there a registry/filter hack to invoke DPL2?

I have changed the guide to use InterVideo's filter