MP internal player doesnt put out AC3

[Lotsofjazz]

TV-Server Version: TV Engine 3
MediaPortal Version: 0.2.3 (stable download of december 25, 2007)
MediaPortal Skin: Monochrome
Windows Version: Vista Ultimate
CPU Type: Intel Core Duo E600, 2.7Ghz
HDD: Samsung SATA3 500Gb
Memory: 4x1Gb DDR2 800Mhz
Motherboard: Abit fatal1ty I90HD
Motherboard Chipset:
Motherboard Bios:
Video Card: ATI Xpress1250 (on board)
Video Card Driver: 8.1
Sound Card: Realtek HD Audio (on Board)
Sound Card AC3: Realtek HD Audio (on Board)
Sound Card Driver: 1.85
1. TV Card: Digital everywhere FloppyDTV-C/CI
1. TV Card Type: DVB-C
1. TV Card Driver:
2. TV Card:
2. TV Card Type:
2. TV Card Driver:
3. TV Card:
3. TV Card Type:
3. TV Card Driver:
4. TV Card:
4. TV Card Type:
4. TV Card Driver:
MPEG2 Video Codec: PowerDVD 7.3
MPEG2 Audio Codec:
Satelite/CableTV Provider:
HTPC Case: Antec Fusion 430 silver
Cooling: Antec tricooler/Scythe Mini Ninja
Power Supply: Antec Fusion 430Watt
Remote: Microsoft MCE
TV: JVC LCD 32S60
TV - HTPC Connection: HDMI/VGA

Hi all,

I have switched to Windows Vista, after another major crash of windows XP. Video has improved, but audio is driving me crazy!

I have downloaded latest ffdshow and AC3filter
Installed PowerDVD7.3 (Ultra deluxe version, including the latest H264 patch)
graphedit to see how the codecs are used
radlight to change the merits of the codecs.

I have several MP4/MKV files that I am sure have AC3 audio(5.1)
Set AC3 filter to passthrough AC3 and DTS to the SPDIF optical output
Set AC3filter as the audio codec in Mediaportal
Set Onboard realtek audio card to send AC3 and DTS through SPDIF (done via Windows device manager, test shows it works)
AC3 filter merit changed to preferred+256 (very high)
PowrerDVD codecs lowered to Normal setting (6000)

Example:
When rendering MP4 file in Graphedit, i see Cyberlink audio decoder PVD7 input is connected to the file and output to the AC3filter and then the preferred audio renderer.. So that is OK. When I open the properties for the Cyberlink audiodecoder, I have to set it to 6 channels to get dolby digital. Play the file with the internal graphedit player generates a rich and perfect AC3 sound!

So that is all OK, you should think, but when opening the same movie in Mediaportal, I get stereo

Checked the directshow filters in Mediaportal, PowerDVDV directshow codecs: Mpeg Hardware decoding ON, H264 hardware decoding ON, Audio decoder SPDIF,.
VMR9 options all checked ON (3), EVR checked ON
Under Movies Player: Audio decoder: AC3 filter
No postprocessing for audio
AC3 filter is set to pass through AC3 and DTS, if input is PCM, AC3 renderer is used, in above example the input in AC3filter is PCM 3/2 5.1, output to SPDIF AC3 5.1

No matter what I try, all I get is stereo with the above MP4 file when played internally in Mediaportal. It is not the only file I have it with, all othe MP4 files show the same issue and also with WMV (VC1) files I experience this problem. Strange enough files with DTS sound it works OK.

I also set in PowerDVD audio configuration to send sound to SPDIF.

This really is driving me crazy!, I got it right in XP, but because I never was able to save the settings (windows collapsed on me unexpectedly) .

Anybody here who got an idea? Do I miss something in mediaportal? It is Mediaportal that decides to use stereo, because Graphedit does play AC3 5.1.

Your help is appreciated

Lots

[Lotsofjazz]

I have cracked it finally!

Most important, get the MPA decoder that comes with mediaportal as the Audio codec in Mediaportal and set ffdshow audio decoder as post pocess, Unregister Dscaler audiodecoder(screws up everything), set ffdshow audio codec to relay everything to spdif, Uncompressed codec set to all supported AC3 and DTS codec set to SPDIF, and dont forget to check the Use SPDIF when AC3 output is set, below the list when DTS or AC3 codec is selected.. this disapears when another codec is selected.

In mediaportal configuration, Directshow filter control, make sure the Powerdvd audio codec is set to SPDIF and also the MPA decoder is set to send DTS and AC3 to SPDIF, AC3/AAC/DTS etc format set to PCM16 (if set higher you get stuttering audio on most HD TV channels), all other options in MPA decoder I leave unchecked

My TV same settings exept for the H254, I do set the cyberlink decoder an in directshow filter control, Powerdvd H262 set to se hardware decodong, No Postprocessing in TV, the MPA decoder works fine with all channels I have, which use Mpeg or AC3.

I am soooo glad I fixed this!. I hope this helps a few to get AC3 DD and DTS out of their home theatre sets :-)

[Dubyahjay]

There is an easier alternative if all you want is unmolested audio from your movies. I.E. you are not trying to matrix channels or mess with the mixer in ffdshow. Install SPDIFER and it will pass AC3 and DTS straight through your SPDIF connection.

[Lotsofjazz]

Originally Posted by Dubyahjay

There is an easier alternative if all you want is unmolested audio from your movies. I.E. you are not trying to matrix channels or mess with the mixer in ffdshow. Install SPDIFER and it will pass AC3 and DTS straight through your SPDIF connection.

You are right if you only have DTS and AC3 movies, but some movies do have Mpeg audio(like MP4 Movies specially encoded for play back on the Sony Playstation 3) and also most SD TV channels use Mpeg for audio, so this requires to have an AC3 encoder like ffdshow or AC3filter. Once encoded into AC3 you can set ffdshow or ac3filter to relay it to the spdif.

With MPA set to SPDIF for AC3 and DTS, these signals are directly relayed to the SPDIF and passes the ffdshow filter untouched, to accomplish this you are right that the Mixer in ffdshow must be left unchecked, and the DTS and AC3 codec set to SPDIF, so it does not try not use the mixer first.

So I have now two codecs for audio that work fine together.. MPA audio decoder as main decoder and and ffdshow audio decoder as postprocess. Without the MPA I could not get it right and was everything, exept DTS, downmixed to stereo. With XP I only used the AC3filter and managed to decode everything as it shoulkd, postprocessing with ffdshow was not necessary.. But with VISTA this apparently did not work anymore (dont ask me why)

Yeah, after days of trial and error I learned a lot about codecs and what their settings exactly do

Lots