8 channel LPCM over HDMI, It's Multi Amp for Everyone

[KOON3876]

everything is trade-off, now my FIR engine only outputs to extended WAV File, but there are pros.

Pros: simple program development and separation, and machine separation, player free.
Cons: Disc area, FIR Parameter changes = reconversion.

1TB is enough to keep hundreds of CD, and only some seconds per music, also I can do batch conversion.

FIR engine is working on my main PC, with GTX280(noisy but crazy fast, and double precision possible - now studying CUDA 2.0 ), then WAV files are stored to NAS.

Audio PC(fanless) reads & play, now I have USB-I2S mode(my own player) and HDMI(Windows Media Player).

I'm thinking to buy fanless 8600GTS - and lower clocked - for Audio PC, to convert in real-time.
DirectSound programming is required and it's quite confusing.
But studying DirectSound is better than studying to make some "plug-in" for foobar, etc.

so..
File: simple program, double precision, x4 area of disc, configurable. (my config is 2PC and NAS).
Streaming: can be "Generic Crossover" device, single precision, difficult programming.

[soundcheck]

OK. Now I understand. You're converting all your files non-realtime. But earlier, before HDMI, you were running realtime conversion, right?

I think it is easier to have a look at the ALSA API or JACK API.
You don't need Directsound in Linux.

Did you have a look at the Brutefir ALSA/Jack output module.
The code is available it's opensource. This might help.

[KOON3876]

Core logic of FIR engine is just a repeating of

incoming Data Buffer (stereo WAV)
copy to GPU, calculate
outgoing Data Buffer (8 channel WAV)

Please check my source.
Wav file management, buffer setup has many codes but core logic should be < 100 lines.

[KOON3876]

Originally posted by soundcheck
OK. Now I understand. You're converting all your files non-realtime. But earlier, before HDMI, you were running realtime conversion, right?

I think it is easier to have a look at the ALSA API or JACK API.
You don't need Directsound in Linux.

Did you have a look at the Brutefir ALSA/Jack output module.
The code is available it's opensource. This might help.

No, I'm not running realtime. Also I separated converter and Player, for my USB-I2S. Keep It Simple for Stupid me.

ALSA or JACK - did you try 8 channel HDMI playback on them?
(the wave file I made is for other people testing other environment)

[soundcheck]

Originally posted by KOON3876


ALSA or JACK - did you try 8 channel HDMI playback on them?
(the wave file I made is for other people testing other environment)

I'll check it out with the ALSA guys!

[flshzug]

Koon, if you ditch your directsound idea and make "plugin" for foobar, it is using the VSTi protocol. It can run not only inside foobar but everywhere else, moreover on linux using WINE. The new vsti protocol supports 64bit read & write too.

[KOON3876]

Originally posted by flshzug
it is using the VSTi protocol.

I got a sample of DirectSound and found, 80% of codes are used for mmio, 3D effect, which I don't need. remaining Dsound initialize / buffer copy / play / circulating buffer are simple enough

and I looked MyEQ VST plugin source code.
Too Huge! I can not understand

also I'm sorry I don't like huge C++ source code which has many platform switching.

[KOON3876]

http://www.portaudio.com/

PortAudio!
I love this "C" style clean, simple library.
will study this.

[KOON3876]

Studying PortAudio see http://www.portaudio.com/

I recommend PortAudio for all of DIYAudio programmer.

PortAudio is open source, MIT-license portable cross-platform Audio API. For example, wave editor 'Audacity' is using PortAudio.

PortAudio works with...
Windows ASIO, MME, DirectSound
Mac Core Audio
Linux (Alsa/Jack/OSS)
maybe 99.999% of audio platform

Programming is really simple.
(1) Intialize, Create, Open, Start Stream
(2) write stream Loop, memcpy from main buffer to stream buffer
(3) Stop, Close, terminate.
That's all. unbelievable.

Studying
(a) build: Done.
needs ASIO SDK, DirectX 9.0 SDK, Windows Platform SDK.
(b) test: Done. sine wav generation
(c) Play stereo wav file: Done.
http://koonlab.com/MultiChannelI2S/WavXPlayer.cpp.txt
I just changed this player's USB section to PortAudio, below 100 lines.

(d) Play 8ch wav file: will try this weekend?
(e) FIR Converter output to stream: next week?
(f) input stream, FIR converter, output stream: next-next weekend? (so far, 44.1/16 CD player)

[KOON3876]

(d) Play 8ch wav file: Done, Please see bottom of
http://koonlab.com/MultiAmpForEveryo...DMI_AVAMP.html

Now we have simple command line - LPCM 8CH Wave file player. There are a little platform dependance? but maybe easy to port to another platform.

Thanks a LOOOOT to PortAudio.

Next I will try to add output , then input streaming to my FIR Converter. Please wait for next weekend

==================

BTW
I can make "NO-GPU" version straight-through FIR channel Divider (stereo wav to 8ch wav). Anyone want it?
it will take 30 minutes to convert 3 minutes music,
but simple to compile and platform (maybe) free.