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Simon Inns
MAME Fan
Reged: 05/14/18
Posts: 4
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Re: DU: The great laserdisc flood
05/14/18 07:59 PM


The duplicator's ADC is 10-bit unsigned; the FPGA converts this to scaled 16-bit signed data (as 16-bit is the only thing the USB3 can pass - you have to transfer 16-bit anyway). Since there is no processing of the sample by the Linux app, that is what is stored on the hard drive.

So you have NTSC capture at 28.63 MSPS @ 16-bit and PAL capture at 35.47 MSPS. The size of the sample depends on the length of the disc, so it's approximately:

1 second NTSC = (2 bytes * 28,630,000 samples) = 54.6 MBytes
1 second PAL = (2 bytes * 35,470,000 samples) = 70.9 MBytes

So if you sample 60 minutes of an NTSC disc (one side of a CLV) you end up with about 200 Gbytes of data or 250 Gbytes for PAL.

Since (as someone pointed out earlier) the disc is pits and troughs the most important thing you get from ADC resolution is actually sensitivity across a wider peak-to-peak RF range (as the signal is weak at the beginning of a disc and strong at the end). So 10-bits was the compromise between need and cost (ADCs get a *lot* more expensive above 10-bits).







Entire thread
Subject Posted by Posted on
* DU: The great laserdisc flood SmitdoggAdministrator 05/12/18 08:39 PM
. * Re: DU: The great laserdisc flood Kitsune Sniper  05/15/18 06:33 AM
. * Re: DU: The great laserdisc flood btribble  05/18/18 04:42 AM
. * Re: DU: The great laserdisc flood Kitsune Sniper  05/18/18 07:44 AM
. * Re: DU: The great laserdisc flood Simon Inns  05/15/18 07:10 AM
. * Re: DU: The great laserdisc flood JonasP  05/15/18 02:01 PM
. * Re: DU: The great laserdisc flood MooglyGuy  05/15/18 04:20 PM
. * Re: DU: The great laserdisc flood Simon Inns  05/15/18 04:43 PM
. * Re: DU: The great laserdisc flood swm3rd  05/16/18 09:03 PM
. * Re: DU: The great laserdisc flood R. Belmont  05/16/18 10:39 PM
. * Re: DU: The great laserdisc flood jonwil  05/19/18 02:32 AM
. * Re: DU: The great laserdisc flood MooglyGuy  05/19/18 10:29 AM
. * Re: DU: The great laserdisc flood Olivier Galibert  05/17/18 11:43 AM
. * Re: DU: The great laserdisc flood happycube  05/18/18 05:19 PM
. * Re: DU: The great laserdisc flood Kitsune Sniper  05/17/18 09:33 PM
. * Re: DU: The great laserdisc flood Roberto Fresca  05/17/18 08:46 PM
. * Re: DU: The great laserdisc flood DoomSooth  05/17/18 01:01 PM
. * Re: DU: The great laserdisc flood agard  05/14/18 07:57 PM
. * Re: DU: The great laserdisc flood gregf  05/14/18 08:56 PM
. * Re: DU: The great laserdisc flood StilettoAdministrator  05/15/18 12:29 AM
. * Re: DU: The great laserdisc flood gregf  05/15/18 12:35 AM
. * Re: DU: The great laserdisc flood agard  05/15/18 12:15 AM
. * Re: DU: The great laserdisc flood gregf  05/15/18 12:30 AM
. * Re: DU: The great laserdisc flood JustNiz  05/15/18 03:20 AM
. * Mad Dog McCree! gregf  05/14/18 04:52 AM
. * Re: Mad Dog McCree! gamerfan  05/18/18 04:31 AM
. * Re: Mad Dog McCree! *=/STARRIDER\=*  05/14/18 04:56 AM
. * Re: Mad Dog McCree! Antny  05/14/18 06:07 AM
. * Re: Mad Dog McCree! gregf  05/14/18 05:02 AM
. * Re: Mad Dog McCree! Antny  05/14/18 06:11 AM
. * Re: DU: The great laserdisc flood casm  05/13/18 02:33 PM
. * Re: DU: The great laserdisc flood italiandoh  05/13/18 12:57 PM
. * Re: DU: The great laserdisc flood f205v  05/13/18 05:01 PM
. * Re: DU: The great laserdisc flood italiandoh  05/14/18 10:03 PM
. * Re: DU: The great laserdisc flood *=/STARRIDER\=*  05/13/18 05:46 PM
. * Re: DU: The great laserdisc flood italiandoh  05/14/18 10:04 PM
. * Re: DU: The great laserdisc flood *=/STARRIDER\=*  05/15/18 05:09 AM
. * Re: DU: The great laserdisc flood RdW  05/14/18 02:30 AM
. * Re: DU: The great laserdisc flood *=/STARRIDER\=*  05/14/18 06:26 AM
. * Re: DU: The great laserdisc flood *=/STARRIDER\=*  05/14/18 02:52 AM
. * Re: DU: The great laserdisc flood CTOJAH  05/13/18 11:25 AM
. * Re: DU: The great laserdisc flood taz-nz  05/14/18 11:32 AM
. * Re: DU: The great laserdisc flood Kitsune Sniper  05/14/18 06:15 PM
. * Re: DU: The great laserdisc flood Roman  05/14/18 06:21 PM
. * Re: DU: The great laserdisc flood Kitsune Sniper  05/14/18 07:39 PM
. * Re: DU: The great laserdisc flood Simon Inns  05/14/18 07:59 PM
. * Re: DU: The great laserdisc flood gregf  05/14/18 09:41 PM
. * Re: DU: The great laserdisc flood JustNiz  05/15/18 02:38 AM
. * Re: DU: The great laserdisc flood Vas Crabb  05/15/18 08:04 AM
. * Re: DU: The great laserdisc flood Olivier Galibert  05/15/18 07:21 AM
. * Re: DU: The great laserdisc flood Kitsune Sniper  05/15/18 04:23 AM
. * Re: DU: The great laserdisc flood Tornadoboy  05/13/18 03:15 AM
. * Re: DU: The great laserdisc flood CTOJAH  05/13/18 11:15 AM
. * Re: DU: The great laserdisc flood StilettoAdministrator  05/14/18 12:28 PM
. * Re: DU: The great laserdisc flood CTOJAH  05/14/18 04:23 PM
. * Re: DU: The great laserdisc flood StilettoAdministrator  05/14/18 07:54 PM
. * Re: DU: The great laserdisc flood italiandoh  05/13/18 12:46 PM
. * I'm excited like a fridge MASH  05/13/18 02:47 AM
. * Re: DU: The great laserdisc flood Master O  05/13/18 02:37 AM
. * Re: DU: The great laserdisc flood btribble  05/12/18 11:36 PM
. * Re: DU: The great laserdisc flood SmitdoggAdministrator  05/12/18 11:41 PM
. * Re: DU: The great laserdisc flood btribble  05/14/18 06:40 AM
. * Re: DU: The great laserdisc flood Kitsune Sniper  05/12/18 11:35 PM
. * Re: DU: The great laserdisc flood MooglyGuy  05/13/18 07:15 AM
. * Re: DU: The great laserdisc flood Kitsune Sniper  05/14/18 07:38 AM
. * Re: DU: The great laserdisc flood CiroConsentino  05/12/18 10:09 PM
. * Re: DU: The great laserdisc flood R. Belmont  05/16/18 10:44 PM
. * Re: DU: The great laserdisc flood Haze  05/16/18 11:00 PM
. * Re: DU: The great laserdisc flood Simon Inns  05/14/18 04:18 PM
. * Re: DU: The great laserdisc flood taz-nz  05/15/18 12:40 PM
. * Re: DU: The great laserdisc flood SmitdoggAdministrator  05/12/18 10:11 PM
. * Re: DU: The great laserdisc flood Shoegazr  05/13/18 01:03 AM
. * Re: DU: The great laserdisc flood JustNiz  05/13/18 03:10 AM
. * Re: DU: The great laserdisc flood Shoegazr  05/13/18 05:13 AM
. * Re: DU: The great laserdisc flood *=/STARRIDER\=*  05/13/18 03:43 AM
. * Re: DU: The great laserdisc flood MooglyGuy  05/13/18 07:08 AM
. * Re: DU: The great laserdisc flood MC68K  05/13/18 07:13 AM
. * Re: DU: The great laserdisc flood Vas Crabb  05/13/18 07:25 AM
. * Re: DU: The great laserdisc flood JustNiz  05/13/18 04:36 AM
. * Re: DU: The great laserdisc flood Vas Crabb  05/13/18 05:55 AM
. * Re: DU: The great laserdisc flood taz-nz  05/14/18 12:39 PM
. * Re: DU: The great laserdisc flood *=/STARRIDER\=*  05/13/18 04:55 AM
. * Re: DU: The great laserdisc flood JustNiz  05/13/18 05:23 AM
. * Re: DU: The great laserdisc flood *=/STARRIDER\=*  05/13/18 05:51 AM
. * Re: DU: The great laserdisc flood JustNiz  05/13/18 08:10 PM
. * Re: DU: The great laserdisc flood John Doe  05/14/18 03:31 AM
. * Re: DU: The great laserdisc flood JustNiz  05/15/18 02:46 AM
. * Re: DU: The great laserdisc flood taz-nz  05/14/18 01:14 PM
. * definitely material for MAME FAQ section imo gregf  05/14/18 04:45 AM
. * Re: Quick link to Aaron's Laserdisc explanation... Bad A Billy  05/14/18 05:28 AM
. * Re: DU: The great laserdisc flood *=/STARRIDER\=*  05/14/18 02:41 AM

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