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View Full Version : grabbing gapless audio from mounted images



yumanoid
20.07.2012, 15:49
i have used daemon tools 4.45.4.0315 to create an image from an audio cd ("gapless" music), first to .mdx format, then .mds format. when i mount any of these two images and then grab audio from the virtual drive using audiograbber 1.83, i get a bonus amount of silence at the end of the .wav file.
this doesn't happen if i grab straight from the physical cd itself in a physical drive. neither it happens when i grab from .img of the same cd (image created with imgburn 2.5.7.0, then mounted in deamon tools).
it took me quite a while to figure out that this is not an issue of the player apps on my android phone that claim to support gapless playback, but in the virtual cd handling on my pc.

is this a normal behaviour or a bug? are you guys aware of this?

ps
sorry if i put this thread in a wrong place, i don't know if it's a bug or a technical issue or what :)

Terramex
25.07.2012, 16:36
Sorry, but can't find a difference between an MDX and a CUE/IMG created with ImgBurn.
Either can i find one between the WAVs extracted with Audiograbber 1.83.
Any non-default settings you're using in Audiograbber ?

How much bonus amount of silence do you detect ?

yumanoid
13.06.2013, 15:48
tried it again with 4.47.1.0333 (sptd 1.83).

created many images of the same audio cd (mike oldfield - the songs of distant earth)

- .mdx with DT
- .mds/.mdf with DT
- .nrg with magic ISO Maker
- .cue/.bin with magic ISO Maker
- .cue/.bin with imgBurn

then i loaded them into DT one by one and verified track-to-track transitions in windows media player 12. results:

- .mdx with DT = GLITCH
- .mds/.mdf with DT = GLITCH
- .cue/.bin with magic ISO Maker = NO GLITCH
- .cue/.bin with imgBurn = NO GLITCH

i then grabbed first three tracks of each virtual cd and also directly from the physical cd. i loaded track2 to audacity to check for the length of silence. i found out, and this is very interesting, that every version of the track (from any virtual cd grab or physical grab) has the same length - 13,116,516 samples. yet the .mdx grabs have 1,176 samples of extra silence (i measured the same number in track2 and track3).

if the track length in samples is the same, but one has silence and the other has none, what does it mean? different start/end offset, plus something else?

btw. i don't think this has anything to do with audiograbber, the glitch/no glitch issue shows during wmp playback, before audiograbber comes into it.

Terramex
16.06.2013, 21:01
As the forum provides more of an additional/secondary user-to-user support please also contact
the official support team (http://www.disc-soft.com/sendmsg/tech) with reference to this thread.

yumanoid
17.06.2013, 14:38
i have just tried the same with a different cd. no glitches in .mdx. seems the issue is with the way the mike oldfield CD is architected.