BASS_ChannelGetLevel(Ex) latency

[Couin]

Hi,

I'm about making some changes about microphone input, to add an Echo effect.
So I need also to change how VU meters and Talk Over (turning ON the Mic input volume when threshold level is reached).

Here is my code :

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rchan = BASS_RecordStart(rdevinfo.freq, 2, 0, 0, 0)

For nSplit = 0 To 1
Splitrchan(nSplit) = BASS_Split_StreamCreate(rchan, BASS_STREAM_DECODE, ByVal 0)
Next nSplit

Call BASS_ChannelSlideAttribute(Splitrchan(0), BASS_ATTRIB_VOLDSP, 0, 10)

rchanfx = BASS_FX_TempoCreate(Splitrchan(0), BASS_STREAM_DECODE Or BASS_FX_FREESOURCE)

Dim echo As BASS_DX8_ECHO
Dim fxrchan As Long

fxrchan = BASS_ChannelSetFX(rchanfx, BASS_FX_DX8_ECHO, 10)
Call BASS_FXGetParameters(fxrchan, echo)
echo.fFeedback = 50
echo.fWetDryMix = 50
echo.lPanDelay = 0
echo.fLeftDelay = 500
echo.fRightDelay = 500
Call BASS_FXSetParameters(fxrchan, echo)

Call BASS_Mixer_StreamAddChannel(MixerMic, rchanfx, BASS_MIXER_CHAN_BUFFER)
Splitrchan(0) is for turning ON/OFF the Mic ( with Call BASS_ChannelSlideAttribute(Splitrchan(0), BASS_ATTRIB_VOLDSP,... ) before FX.
Splitrchan(1) is for permanent measuring the Mic input for the Talk Over.
Because I don't want to turn off the echo when I turn off the Mic.

And in a timer:

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Call BASS_ChannelGetLevelEx(Splitrchan(1)... 'For Talk Over
...
Call BASS_ChannelGetLevelEx(rchanfx... 'For Mic after FX
But there is around 2 seconds of delay for the Talk Over, I mean the Talk Over, it turns ON 2 seconds after hitting the Mic cartridge.

I pretty to have already seen this problem but after search on my archives and on the forum, I don't retreive the solution, to avoid this delay.

BASS_ATTRIB_BUFFER on Splitrchan did not resolved the problem.

An idea ?

Thanks

[Couin]

I created another mixer and I send Splitrchan(1) to this mixer, and it looks the delay gone.

I the device setup here is the code I added:

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MixerNull = BASS_Mixer_StreamCreate(44100, 2, BASS_SAMPLE_FLOAT Or BASS_MIXER_NONSTOP)
Call BASS_ChannelSetAttribute(MixerNull, BASS_ATTRIB_BUFFER, 0)
Call BASS_ChannelStart(MixerNull)
After Call BASS_ChannelSlideAttribute(Splitrchan(0), BASS_ATTRIB_VOLDSP, 0, 10), I added:

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Call BASS_Mixer_StreamAddChannel(MixerNull, Splitrchan(1), BASS_MIXER_CHAN_BUFFER)
And for measure (for Talk Over):

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Call BASS_Mixer_ChannelGetLevelEx(Splitrchan(1), ...And it looks ok with no delay.

I will keep this solution, unless there is a better way to do

[Ian @ un4seen]

But there is around 2 seconds of delay for the Talk Over, I mean the Talk Over, it turns ON 2 seconds after hitting the Mic cartridge.

I pretty to have already seen this problem but after search on my archives and on the forum, I don't retreive the solution, to avoid this delay.

BASS_ATTRIB_BUFFER on Splitrchan did not resolved the problem.

An idea ?

It looks like you're on the right track with setting BASS_ATTRIB_BUFFER=0, but that can't be applied to "Splitrchan" because it's a decoding channel (BASS_STREAM_DECODE), which means it has no playback buffer. It could instead be applied to "MixerMic", which has the playback buffer.

[Couin]

Hi Ian

For Talk Over (based on level detection of input device), I need to pick the level before applying the volume on Splitrchan(0). That's why I would get the Splitrchan(1) level, but earing it from the output.
MixerMic receive the channel (rchanfx) where echo is applyed after applying volume (because I do'nt want to cut the echo when I turn the volume off of the input).