How about the ability to invert either the left or right channel.
#1
I have noticed that sometimes "release groups" (not sure what they release, I'm new to the internets) will have one of their audio channels out of phase with the other.
It would be nice to be able to invert one or the other so I don't have to select only left, or only right.

If no one else ever has these problems, then disregard, I'll live for the 1.5 hours here and there.




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#2
invert? Huh
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#3
I assume he refers to the inversion you do when you shift + and - on a loudspeaker connection. I have no idea how this is done digitally, possibly by introducing a slight delay would have the same effect
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#4
Some more info on the subject

Quote:Phase

Audio waveforms are cyclical; that is, they proceed through regular cycles or repetitions. Phase is defined as how far along in its cycle a given waveform is. The measurement of phase is given in degrees, with 360 degrees being one complete cycle. One concern with phase becomes apparent when mixing together two waveforms. If these waveform are "out of phase", or delayed with respect to one another, there will be some cancellation in the resulting audio. This often produces what is described as a "hollow" sound. How much cancellation, and which frequencies it occurs at depends on the waveforms involved, and how far out of phase they are (two identical waveforms, 180 degrees out of phase, will cancel completely).

Phase Invert

A switch found in the input sections of mixing consoles and mic preamps.
The term "phase invert" is actually a misnomer, since what the switch really does is invert the polarity of the signal in that input (correct usage would be "polarity invert").
Its intended use is to correct for balanced lines and mics that are wired backwards. In some cases toggling the phase invert switch may make a sonic difference if signals are out of phase, but doing so will also put that signal out of polarity with the others.
Always read the XBMC online-manual, FAQ and search the forum before posting.
Do not e-mail XBMC-Team members directly asking for support. Read/follow the forum rules.
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#5
Correct Pike, some of the videos on the internet have one of their audio channels inverted, the same basic idea as swapping the positive and negative around, because it makes one of the channels 180 degrees out of phase with the other, when you try to play it through a stereo with surround sound all the peaks and valleys from one side cancel out the other, resulting in a muffled output to the left and right and since thats how dolby encodes the rear channels into a stereo signal (rear channels can be decoded primitively by connecting two speakers normally, but instead of connecting their negatives to the amplifier, connect the negatives on the speakers together, Warning!, doing so with certain amplifiers could damage them) ie. surround is the difference between the left and right channels.
If one of the channels is out phase then the dolby decoder cannot decode it properly.

It's been awhile since I played with audio source code, are the raw samples in the form of +/- 65535, I may be wrong, but can't you just invert them by multiplying them by -1?

Sorry if I'm not making much sense, I'm more of an hardware guy, rather then a software guy.
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#6
even hw guys should know there's no such thing as a 17 bit variable ;P
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#7
Ok, so I'm just more of a guy.

I think maybe those numbers are from an int86() call for mouse acceleration, but you get the idea, isn't the raw data for each channel stored like that, in positive and negative numbers, negatives being the valleys, and well, you know.

Or maybe not, you guys are the software gurus, you tell me.
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#8
dont be stuck up now, it was a joke.

and you are correct 16bit pcm is usually signed -32k..32k-1
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#9
Was hoping I wasn't losing my mind. Smile
I would be the last to know, of course.

So, am I the only one who ever has this problem? (the inverted channel one, not the losing my mind one)
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How about the ability to invert either the left or right channel.0