SVCD Multichannel (Linux NOT needed)

[Juhan]

I have created a perfect SVCD MPEG-2 MC 5.1 test clip under Windows which works 100% perfectly on my Philips DVD-752 (using analog 5.1 outputs). Multichannel decoding is done internally on my player (digital output is NOT working - only analog 5.1 outputs are working).

Tools needed:
1. SoftEncode 1.0 (for decoding AC3 to separate PCM streams)
2. Philips MPEG Audio tools (Search Google for 'philips mpeg tools bitstreams')
3. TMPGEnc (for muxing)

NB! 'pub_enc.exe' (included in MPEG Audio Tools) is exactly the same program as 'musicin' in Linux. And 'raw2audio.exe' does the same thing as 'pcm2aiff' in Linux. And Linux program called 'ch_wave' is NOT needed after all.

Job description:

1. Open AC3 file in SoftEncode (decode as PCM)
SoftEncode creates 6 temporary files (*.tmp) into TEMP directory (it depends on windows you are using - it can be '\Windows\Temp' or something else. Type 'SET' from command prompt and you can see where the variable TEMP points to). These files are pure PCM files with no headers. If you sort them by name the 1st file contains 'Left Channel' data, the 2nd is 'Center', 3rd is 'Right Ch', 4th is 'Left Surround', 5th is ' Right Surround' and the last is 'LFE' data.

2. Create one big AIFF file with 'raw2audio.exe'
Example: raw2audio.exe -s48000 -oOutput.aiff LeftPCMfile RightPCMFile CenterPCM LFEpcm LSpcm RSpcm

3. Encode the MPEG-2 5.1 MC file from AIFF file.
Example: pub_enc.exe -m s -n d -o -L Output.aiff
It creates Output.mpg

4. Mux 'output.mpg' with your video file using TMPGEnc MPEG Tools and that's it. Enjoy MPEG-2 5.1 Surround sound!

Many players with 5.1 analog outputs should play MPEG-2 5.1 audio. At least Philips players should. Do not use digital outputs because they are not working.

NB! dvd2svcd author, maybe you can add support for these programs ?

[Doom9]

step1 w/o the use of any commercial tools: besweet has a -6ch switch that will decode each channel of a 5.1ch AC3 file to a separate WAV file. But.. I think we've properly established (in the audio forum) that there are like 2-3 players that can properly play mc SVCDs (yours is in that list already).

[Juhan]

Thanks Doom9, BeSweet is easier to use. It has also '-6haiff' switch to create 6channel AIFF file directly form AC3.

But, there is a 2 Gb limit problem in 'pub_enc.exe'. It cannot read files bigger than 2 Gb and stops encoding at frame 157192.

The only way is to split AC3 file into 2 files, encode the files separately with 'pub_enc' and add the result (2 MPG files) together ?

Can anyone point me a good tool that splits AC3 files correctly ?

[Mozart]

lets suppose that you have 6 vob files with the same size. What about to extract the ac3 file from the first 3 vobs, save it as, for example, "audio_stream_1a.ac3" and do the same with the others 3 vobs? Afther this you can encode each one half...

[Juhan]

Thank you, Mozart!

I figured that out myselt that it is easier to split AC3 but I managed to edit my last post at the same time you posted reply.

AC3 has packets with headers (384 kbit) and if I take 3 vobs for the first half and the other 3 vobs for the second half then there could be a situation that half of the packet is in the first AC3 file and the other half is in the second AC3 file (for example 100 kbits in the 1st AC3 and 284 kbits in the other).


The best way is to split AC3 between 2 packets.

[Mozart]

This problem with the header cannot happen... Do you remember that we can demux the ac3 file from any vob - and any set of vobs - using DVD2AVI?

[Juhan]

It seems that the problem was not 2Gb limit after all. I used HeadAc3he to split AC3 file. The first half had 153643 frames (pub_enc frames) and the second half stopped at 3549. 153643+3549=157192. There must be problem with the sound file (AIFF). The encoder doesn't like something. I'll try to find out what the problem is.

[Tokafondo]

Greetings from Canary Islands.

I am VERY interested in getting the Philips Tools. I've searched in google, altavista, yahoo, etc and all I have is lots of information but not the tools themself.

I have a AC3/DTS/MC Philips receiver and I want to test if trought the S/PDIF out of my soundcard (ct5880) the Philips will recognize the MC stream instead of the 2 channel stream.

Thanks for you answering this.

[gerti67]

Hi Tokafondo,

look here if these are the tools you are looking for:

http://www.licensing.philips.com/ordering/soft/documents343.html

Greetings,
Gerti