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--aps -b192 with 128/160 frames?, How did this happen?
getID3()
post Oct 7 2003, 23:00
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I came across a sample file that I'm having trouble figuring out how it was encoded. According to the LAME tag, it's encoded with LAME v3.92 and while v3.92 doesn't actually store the preset used, according to the rest of the info in the LAME tag it appears to be encoded using --alt-preset standard (vbr_quality = 78; vbr_method = vbr-old / vbr-rh; noise_shaping = 2; stereo_mode = joint; ath_type = 4; lowpass = 19000). The problem is that the LAME tag also says that a minimum bitrate of 192kbps was specified, and yet the actual bitrates are distributed like this (which looks like normal --aps):
QUOTE
128 -> 4
160 -> 963
192 -> 2658
224 -> 817
256 -> 246
320 -> 65
I haven't been able to replicate how the LAME tag has minimum bitrate of 192 but 128 and 160 frames appear in the file. I've tried:
--alt-preset standard -b 192
--alt-preset 192
--abr 192


Any ideas anyone?


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getID3() = PHP audio & video metadata parser: http://getid3.sourceforge.net
Current version: v1.7.0 (released January 19, 2004)
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ViPER1313
post Oct 7 2003, 23:23
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My guess is that it was encoded w/ a dll version of v3.92, like the one found in CDEX. My guess is that the person selected the APS settings, and also selected a minimum bitrate of 192kbps (I know you can do this in CDEX.) It will not effect the output of the file at all - it will be a standard APS file - it MAY affect the value in the LAME tag though..... I don't have CDEX installed at the moment, so I can't test the theory. Hope this helps.

Edit - Installed and tested w/ CDEX v1.51, my above theory does not seem to be true. Setting a minimum bitrate of 192kbps actually does force a min bitrate of 192....so I guess my guess was wrong rolleyes.gif . Good luck!

This post has been edited by ViPER1313: Oct 7 2003, 23:29
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