View Single Post
Old 25th August 2021, 23:30   #15103  |  Link
Etroxamin
Registered User
 
Join Date: Jul 2021
Location: Bremen, Germany
Posts: 36
it might have been discussed here already, i would guess, but i only found little information about it:

when i demux a normal .dts file (in this case a 320kbps 2.0 dts track) eac3to says: patching dts to 24 bits.
mediainfo tells me the dts track inside m2ts file is 16 bit, there is a switch: -dontpatchdts - if I use it i get a file of the same size (down to the last byte). However on a wiki i read that -dontpatchdts switch applies a dither.

will this switch really apply a dithering to a normal .dts file?
and is the patching to 24 bit change anything else than a metaflag change somewhere inside the dts file?

as far as i have understand it, lossy audio usually dont have a bit depth at all, but for some reason a dts file has a flag, to be able to be copied to an audio disc, as there are also some dts audio tracks and it seems to be mandatory to have that flag on a audio disc.

actually i would like to keep the 16 bit flag, even if it doesnt change anything, that 24 bit however would just be pointless if i can demux it without that 24 bit patching, and without damaging the file of course (which would be the case with dithering in same way). As this whole patching thing amplifies the uselessness of that information, i think.

But for dithering i would expect that eac3to needs to reencode the file, but with the -dontpatchdts switch, eac3to just says extracing track. it takes the same time too (almost, 2secs more 9m 24s vs 9min 26s, but i doubt that the 2 secs are enough to reencode and dther), so i would strongly guess that dither only is applied to lossless dts-hd when decoing to wav or flac or that the information on the wiki is misleading,

so my final question is: is it save to use the -dontpatchdts switch to keep the (useless) bit flag as it is?

I would guess yes, but maybe someone here can give me more information, so that i feel more satisfied doing it
Etroxamin is offline