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Old 19th April 2018, 10:39   #27  |  Link
tebasuna51
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Join Date: Feb 2005
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Quote:
Originally Posted by doomleox999 View Post
I still don't get the same result I get when encoding with ffmpeg (2ch sounds the same as original 6ch)
I can't understand how 2 ch sound the same as 6 ch.
2 speakers can supply the same volume than 6 speakers?
Do you listen the 6 ch in a 6 speakers system?

Quote:
Is it OK to encode the mkv directly to aac or m4a or is better to extract the audio and encode that file?
It is the same, some soft (eac3to, ffmpeg) can do the 4 task (extract, decode, downmix and recode) in 1 job.

Quote:
Because something weird happens when I extract the audio. If I open it, MPC-HC tells me its lenght is 1 h 22 min but Windows Explorer says 3 h 46 min.
If you want know exactly the info about a AAC audio you need extract the aac and use a soft than read the full file like LeeAudBi, you can't trust in MPC-HC, Windows Explorer or MediaInfo.

Quote:
But when I check the MeGUI log I think the program is ignoring the script, maybe because of the options I choose:
Another weird thing is that MeGUI takes like 50 min to encode the audio,
It is not normal, please supply the MeGUI log.

Quote:
Originally Posted by mkver View Post
But does anybody have a definitive answer why ffmpeg uses different coefficients for float and non-float?
Good question, but we can force the coefficients using the filter -af "pan=stereo..."

Then you can select the coefficients with ffmpeg and with AviSinth, and obtain the same.

Quote:
Probably it is because one doesn't need to care about clipping that much if one uses float output.
But at some point in the chain of conversion between digital to analog audio all values over 1.0 are clipped.

You need Normalize or accept distort audio, maybe only a few points and you don't care in this sample, but we can't expect that always.
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Last edited by tebasuna51; 19th April 2018 at 10:43.
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