Problem using GraphEdit for AAC audio conversion

[Adrenaline-rush]

Hi All,

Untill recently i was able to use graph edit for converting any AAC audio to AC-3. Primarily because AAC audio in an AVI/TS/M2T file is somehow not played properly by my PS3 , which is my main media machine tio stream any kind and every kind of playable content.

The AAC demuxed from any MKV is simply to be dragged and dropped in the GraphEdit work area and it would construct a filter graph for the audio decoding chain, which I can later amend manually by ffdshow-directshow filters to read and output the AAC file into an AC-3 file.

Everything was working fine, when suddenly after quite sometime i needed to convert an AAC file and when dragged and dropped to GraphEdit, it displays an error as shown in the attached image file.

Can anyone guide me as to what am I doing wrong. I have not uninstalled any of the previous directshow filters I have and all the settings are intact. I guess i may have installed dBpoweramp for testing purpose but it should'nt make any working program go haywire.

Any ideas and help is highly appreciated.

Regards,
Myself.

[clsid]

You probably haven't got a parser installed for .aac files.

But why are you demuxing the Matroska file? You can just use that in your graph instead of the demuxed audio file.

[Adrenaline-rush]

Well i have got FFDShow installed and working properly and AAC is enabled via ffshow as shown in these images. Anything else you can suggest or guide, I would be happy to do that. I using demuxed AAC audio stream because I want to covert it into AC-3 and remux it again in the H.264 video stream from the MKV file to enclose it in a M2TS container playable on PS3 via the DLNA server.

[clsid]

I repeat: ffdshow is only a decoder, not a parser.
I repeat: there is no need to demux

Stop attaching images to your post. Nobody can see them until they are approved by a moderator. Use some online image host.

[tebasuna51]

Use DirectShow for audio transcoding is always a bad choice. You have poor control over decoder/encoder parameters and the DirecShow config can change from one PC to other or by some software change.

To transcode AAC -> AC3 using free methods you have other choices (always using the Aften encoder):

- Command line method using Faad decoder and intermediate wav file.
- AviSynth methods using Bass decoder (SoundOut, Wavi, BeHappy, ...)
- GUI method with Foobar2000 decoder (the Aften encoder can be configured to convert the aac to the ac3 file directly)

Select your preferred method and ask if you need more help.

[Adrenaline-rush]

I repeat: ffdshow is only a decoder, not a parser.
I repeat: there is no need to demux

Stop attaching images to your post. Nobody can see them until they are approved by a moderator. Use some online image host.

Thank you for repeating Clsid.

Please guide me after repitition if ffshow is only a decoder then which one is the parser for AAC file and how can I install it and how can I make it work in Graph Edit . Any quick tips?

If there is no need to demux the MKV file then how can I import the MKV in graphedit and output only the sound stream convereted in AC-3 and maybe remuxed in the original MKV again. Any guidance in it is also appreciated.

I use and prefer GraphEdit for conversion instead of using any aften based method particularly because its a one-step hassle free conversion procedure since I dont need any effects / editing to the original AAC file.

I have not attached anymore images

Thanks.

[clsid]

Render mkv file in GraphEdit. Remove only the audio and video renderers. Connect your preferred audio encoder to the audio decoder. Connect Matroska muxer. Connect that to file writer.

Or if you only want to encode the audio: Remove all video filters. Connect audio encoder to file writer.

[tebasuna51]

I use and prefer GraphEdit for conversion instead of using any aften based method particularly because its a one-step hassle free conversion procedure since I dont need any effects / editing to the original AAC file.

Is your choice of course.

For me isn't "a one-step hassle free conversion procedure" because I use ffdshow to play multichannel audio by analog output (not ac3 SPDIF transcode), and with some touch not recommended for transcode, then I need reconfigure ffdshow between play/transcode options.

Remember also than ffdshow ac3 encoder output is always -6dB low volume than aften or recent ffmpeg encoders.

Render mkv file in GraphEdit. Remove only the audio and video renderers. Connect your preferred audio encoder to the audio decoder. Connect Matroska muxer. Connect that to file writer.

Maybe is my fault but the ac3 audio in the output mkv is unknow:
A_MS/ACM, unknow(ID 2, type: audio)
and play only video.

The ac3 only output make a correct (but -6 dB low volume) ac3.

[Adrenaline-rush]

Thanks for helping. But unfortunately the problem still remains. I also tried installing the AAC parser from http://www.inmatrix.com/zplayer/formats/aac.shtml but still the file cannot be opened in GraphEdit.

The source MKV file however plays fine with JetAudio. And in Jetaudio the ffdshow is happily used to decode the aac source audio. But when the separate AAC stream is imported in GraphEdit, it somehow rejects it. It was however working fine and I did use it numerous times.

Upon Clsid's suggestion I imported the source MKV in graphedit and then deleted the Video Decoding chain. Then deleted the default directsound device from audio decoding chain and inserted file write at the end. I am trying with it right now and maybe it would render a compatible AC3 file. Nonethless I am happy if it works the alternate way, but would still like to learn what has gone wrong.

For the -6dB low volume in conversion via ffdshow decoder, I believe I would try to compensate for it, by testing the limits of Yamaha YHT-185 5.1 Channel Surround Sound Home Theatre which is main sound amplifier used when MKV is streamed via DLNA server to the projector screen.

Thanks for support.

[gwire]

Render mkv file in GraphEdit. Remove only the audio and video renderers. Connect your preferred audio encoder to the audio decoder. Connect Matroska muxer. Connect that to file writer.

Or if you only want to encode the audio: Remove all video filters. Connect audio encoder to file writer.

It seems to me that there is no surefire way to do this. I used to use graphedit to transcode my mkv 5.1 and 7.1 aac audio to ac3 5.1 audio. I will tell you this: ITS COMPLETELY UN RELIABLE!!

I would simply just drag the mkv file into graphedit and it would render. At first I would remove the video chain and then remove the default directsound device. Then I would attach a new filter to using file writer to the ffdshow audio decoder. That worked once or twice. the file size was anywhere from 300 mb to 500 mb. Inconsistant. None the less i still played surround. Then it would just start to create a never ending file. if i dont stop it it would fill up my hard drive.

So then I tried it the same way but did not delete the video chain. It seemed to work fine for a while and played the video while recoding. the audio recode would finish half way before the video did. None the less it worked. but all of a sudden for no %$^%$$% reason back to a neverending %$& file size. WTF.
I found a freeware progam that is just brilliant!! it will recode entire directories of mkv 5.1 aac files to 5.1 ac3 reliably every @!$# time. It will remux also. Just point to the file or directory and run. THATS IT!! SET IT AND FORGET IT!
Works every time.

My problem is some times an mkv file will have a problematic aac file. I would just like a surefire alternate way to test this out.

So could someone please explain to me how to step by step, like i was a !@#$% 2 year old, HOW TO DO THIS! I dont care if its graphedit or whatever. I just would like a staight foward solid as a %#%$# rock simple to do solution!

Thank you in advance for all your help and support.