ok...i have done some tests...here are the results...the qtaacenc encoder accepts wav's up to 32float (mono or stereo ONLY)...if found that is limited (an old apple flaw!!!) to maximum 186 minutes for a 32float@48000hz wav or 279 minutes for a 24bit@48000hz wav and 327 minutes for a 16bit@48000hz wav!!!the 4gb limit is on apple side of the encoder...i test it using the STDIN input by feeding a +8hrs .ac3 file with 16, 24, 32, 32float bits..._OT: @nao considering your expertise in windows iTunes libraries do you think a CLI raw (or full) mp4 muxer can be done? (.h264 + .acc + softsubs [apple style] + chapters [apple style])something like subler for mac...http://code.google.com/p/subler/_
@punkrockdudeI noticed this too. Also when i encode files in iTunes or with iTunesEncode.It seems that QuickTime auto-scales the volume down to avoid clipping.
ALAC never clips.
It seems that QuickTime auto-scales the volume down to avoid clipping.
I implicitly trust lvqcl, so I won't continue to make an issue out of this except to say one can easily take a loud and likely "clippressed" track that routinely peaks at full-scale, encode and then decode to see if it has a reduction in level.
Quick test:lame -V 6.248: 126 kbpslame -V 6.249: 115 kbpsqtaacenc --tvbr 59: 135 kbpsqtaacenc --tvbr 58: 105 kbps(and qtaacenc --tvbr 58 --samplerate keep: 114 kbps)I cannot say that 126 is 'much lower' than 135 kbps.
It looks like limiter really. Something like 'advanced limiter' in foobar2000...It doesn't change input signal if it is less than -0.5 dBFS (approximately!).
Both iTunes and iPod will stop playback at 71.6% through a file.
Hi,Any comments or questions are accepted in this thread.Thanks
Maybe a bit off-topic, but would it be possible to add alac 24bit encoding to this tool?
Original WAV file (peak and gain taken from an WavPack encoded from it)Peak: 0.999908Gain: -6.61 dBqtaacenc file (directly encoded from WAV via command prompt, --tvbr 127 --highest)Peak: 0.968920Gain: -6.18 dBiTunes (directly encoded from WAV in iTunes, 320kbps, CVBR)Peak: 0.969976Gain: -6.18 dBChecked with Nero AAC (in foobar2000, Q1.0)Peak: 1.020406Gain: -6.60 dB
Are these bitrates values correct for qtaacenc?:Target Quality - True VBR AAC (Powered by QuickTime & CoreAudio):Q50 - Q58 = ~115 kbps
In the listening test thread, two testers got ~128 kbps for Q58
Nope, it was Q59.
I don't understand why it is called an "issue" and why anyone would want to disable it (and get guaranteed clipping at these levels).
Because, I assume, they use Replaygain which, unlike QuickTime's limiter, will prevent clipping without affecting dynamics (though, whether it makes an audible difference...).