I have been trying to use ddrescue to make a good copy of a DVD that only
works in some of my DVD players. I actually got it to work with one DVD,
but the other one gets so far and then, after several hours, the screen
looks like this:

***
# ddrescue -v -b 2048 -r 4 /dev/sr0 D1.iso D1.log
GNU ddrescue 1.23
About to copy 7255 MBytes from '/dev/sr0' to 'D1.iso'
Starting positions: infile = 0 B, outfile = 0 B
Copy block size: 32 sectors Initial skip size: 64 sectors
Sector size: 2048 Bytes

Press Ctrl-C to interrupt
ipos: 4415 MB, non-trimmed: 360116 kB, current rate: 0 B/s
opos: 4415 MB, non-scraped: 0 B, average rate: 79775 B/s non-tried: 1716 MB, bad-sector: 0 B, error rate: 8192 B/s
rescued: 5179 MB, bad areas: 0, run time: 18h 2m
pct rescued: 71.37%, read errors: 5569, remaining time: n/a
time since last successful read: 16h 30m 43s Copying non-tried blocks... Pass 5 (forwards)
***

Note that the last successful read time is over 16 hours. At this point,
the numbers in the left column have long since quit incrementing, while the numbers (that are not 0) in the other two colums are the only ones going up.

I have searched on the internet about this. Some folks talk about theirs
going days without ever stopping on its own. Others point out that
sometimes you can CTRL-C out and the iso you get will be mostly OK. Mine unfortunately was not. :)

Is there anything I should think about changing on the command line to get better results?


* SLMR 2.1a * I am Popeye of Borg. Prepare to be askimilgrated.

---
■ Synchronet ■ CAPCITY2 * capcity2.synchro.net * Telnet/SSH:2022/Rlogin/HTTP

Re: ddrescue
By: Dumas Walker to ALL on Mon Feb 08 2021 03:45 pm

I have been trying to use ddrescue to make a good copy of a DVD that only works in some of my DVD players. I actually got it to work with one DVD, but the other one gets so far and then, after several hours, the screen looks like this:

***

so what is the DVD of? is it something like family movies, or is it something you can download.

if you can just download it off the internet, i recommend that.
---
■ Synchronet ■ ::: BBSES.info - free BBS services :::

Re: ddrescue
By: Dumas Walker to ALL on Mon Feb 08 2021 03:45 pm

I have been trying to use ddrescue to make a good copy of a DVD that only works in some of my DVD players. I actually got it to work with one DVD, but the other one gets so far and then, after several hours, the screen looks like this:

***
# ddrescue -v -b 2048 -r 4 /dev/sr0 D1.iso D1.log
GNU ddrescue 1.23
About to copy 7255 MBytes from '/dev/sr0' to 'D1.iso'
Starting positions: infile = 0 B, outfile = 0 B
Copy block size: 32 sectors Initial skip size: 64 sectors
Sector size: 2048 Bytes

Press Ctrl-C to interrupt
ipos: 4415 MB, non-trimmed: 360116 kB, current rate: 0 B/s
opos: 4415 MB, non-scraped: 0 B, average rate: 79775 B/s non-tried: 1716 MB, bad-sector: 0 B,
error rate: 8192 B/s
rescued: 5179 MB, bad areas: 0, run time: 18h 2m pct rescued: 71.37%, read errors: 5569, remaining time: n/a
time since last successful read: 16h 30m 43s Copying non-tried blocks... Pass 5 (forwards)
***

Note that the last successful read time is over 16 hours. At this point, the numbers in the left column have long since quit incrementing, while the numbers (that are not 0) in the other two colums
are the only ones going up.

I have searched on the internet about this. Some folks talk about theirs going days without ever stopping on its own. Others point out that sometimes you can CTRL-C out and the iso you get will be mostly OK. Mine unfortunately was not. :)

Is there anything I should think about changing on the command line to get better results?

* SLMR 2.1a * I am Popeye of Borg. Prepare to be askimilgrated.

I don't do a lot of optical media rescuing with ddrescue, but the idea is that you have to perform the reads using multiple
devices.

Say you have a bunch of defective sectors. Some optical media reader is capable of reading 33% of them. Another media reader
can read 50% of them. And another media reader can read 39% of them. Hopefully if you run ddrescue with each reader, and put
the results together, you can rebuild the whole iso or at least the most of it.

You could run a round of reads using the -n switch, which should speed things up quite a bit. Reduce the number of retries too
- there is no point in trying 4 times for the sector in a first run. You will retrieve less data with each pass, but the thing
is that if 30% of the image is unreadable after the first run you know you can put the DVD into the trash and need waste no
more time :-)


--
gopher://gopher.richardfalken.com/1/richardfalken

---
■ Synchronet ■ Palantir BBS * palantirbbs.ddns.net * Pensacola, FL

so what is the DVD of? is it something like family movies, or is it something u can download.

if you can just download it off the internet, i recommend that.

I might be able to download it, I have not looked. People talk about downloading things but I am not sure where they find them. It is a DVD I bought.

I need to get smarter about those things. :)


* SLMR 2.1a * Photons have mass? I didn't know they were Catholic...

---
■ Synchronet ■ CAPCITY2 * capcity2.synchro.net * Telnet/SSH:2022/Rlogin/HTTP

is that if 30% of the image is unreadable after the first run you know you can
ut the DVD into the trash and need waste no
more time :-)

I had not thought of it that way but I bet you are right. Thanks!


* SLMR 2.1a * Trespassers will be shot, survivors will be shot again!

---
■ Synchronet ■ CAPCITY2 * capcity2.synchro.net * Telnet/SSH:2022/Rlogin/HTTP

Arelor wrote to Dumas Walker <=-

@MSGID: <6022532A.385.dove-unix@palantirbbs.ddns.net>
@REPLY: <6021A2F5.2616.dove-nix@capitolcityonline.net>
Re: ddrescue
By: Dumas Walker to ALL on
Mon Feb 08 2021 03:45 pm

I have been trying to use ddrescue to make a good copy of a DVD that only works in some of my DVD players. I actually got it to work with one DVD, but the other one gets so far and then, after several hours, the screen looks like this:

***
# ddrescue -v -b 2048 -r 4 /dev/sr0 D1.iso D1.log
GNU ddrescue 1.23
About to copy 7255 MBytes from '/dev/sr0' to 'D1.iso'
Starting positions: infile = 0 B, outfile = 0 B
Copy block size: 32 sectors Initial skip size: 64 sectors
Sector size: 2048 Bytes

Press Ctrl-C to interrupt
ipos: 4415 MB, non-trimmed: 360116 kB, current rate: 0 B/s
opos: 4415 MB, non-scraped: 0 B, average rate: 79775 B/s

no

n-tried: 1716 MB, bad-sector: 0 B,

error rate: 8192 B/s
rescued: 5179 MB, bad areas: 0, run time: 18h 2m pct rescued: 71.37%, read errors: 5569, remaining time: n/a
time since last successful read: 16h 30m 43s

Co

pying non-tried blocks... Pass 5 (forwards)

***

Note that the last successful read time is over 16 hours. At this point, the numbers in the left column have long since quit incrementing, while the

n

umbers (that are not 0) in the other two colums

are the only ones going up.

I have searched on the internet about this. Some folks talk about theirs going days without ever stopping on its own. Others point out that sometimes you can CTRL-C out and the iso you get will be mostly OK. Mine

unf

ortunately was not. :)

Is there anything I should think about changing on the command line to get

be

tter results?

* SLMR 2.1a * I am Popeye of Borg. Prepare to be askimilgrated.

I don't do a lot of optical media rescuing with ddrescue, but the idea
is that you have to perform the reads using multiple devices.

Say you have a bunch of defective sectors. Some optical media reader is
capable of reading 33% of them. Another media reader can read 50% of them. And another media reader can read 39% of them. Hopefully if you
run ddrescue with each reader, and put the results together, you can rebuild the whole iso or at least the most of it.

You could run a round of reads using the -n switch, which should speed things up quite a bit. Reduce the number of retries too - there is no point in trying 4 times for the sector in a first run. You will
retrieve less data with each pass, but the thing is that if 30% of the image is unreadable after the first run you know you can put the DVD
into the trash and need waste no more time :-)

Trying a different drive will probably help more than using different command line switches. IF the problem is degradation of the media, subtle differences in the lasers between drives can lead to different results. You mention it worked on one drive, so do you have someone elses machine you can use? IS the disk scratched?

I have found that some drives might barf on one disk where another doesn't. I'd be interested to know how you stick multiple failed ISO's together. I found my Doom 3 CD's (original, not pirate, two of them would fail one my desktop, but I was able to read them on my laptop.

IF the degradation is affecting a portion of the disk (ie, its not just one or a few sectors), well, unless you can get it working on another drive, its likely gone.



... MultiMail, the new multi-platform, multi-format offline reader!
--- MultiMail/Linux v0.52
■ Synchronet ■ MS & RD BBs - bbs.mozysswamp.org

Re: ddrescue
By: Dumas Walker to MRO on Tue Feb 09 2021 04:10 pm

so what is the DVD of? is it something like family movies, or is it something u can download.

if you can just download it off the internet, i recommend that.

I might be able to download it, I have not looked. People talk about downloading things but I am not sure where they find them. It is a DVD I bought.

I need to get smarter about those things. :)

just come on my irc or my bbs and msg me and give me your email address. i'll download it for you. there's no use going through all these troubles over a movie.
---
■ Synchronet ■ ::: BBSES.info - free BBS services :::

Re: ddrescue
By: Dumas Walker to ALL on Mon Feb 08 2021 03:45 pm

I have been trying to use ddrescue to make a good copy of a DVD that only works in some of my DVD players. I actually got it to work with one DVD, but the other one gets so far and then, after several hours, the screen looks like this:

If the DVD is scratched and thats why it's having trouble, you might be able to get better results trying to address the physical damage. I've been using some plastic polish that I got off amazon for other things. It works well.

---
■ Synchronet ■ [Stupendous BBS - bbs.stupendous.net]

I have been trying to use ddrescue to make a good copy of a DVD that only
works in some of my DVD players. I actually got it to work with one DVD, but the other one gets so far and then, after several hours, the screen looks like this:

If the DVD is scratched and thats why it's having trouble, you might be able t
get better results trying to address the physical damage. I've been using some
lastic polish that I got off amazon for other things. It works well.

In this case, it was not scratched, but thanks for that info!

I was able to get just about all of the data off using Handbrake. Seems
like the areas having issues were the ones that contained the DVD menu and
some of the extras. I was able to get most all of what I really wanted off
of it, and I think i can get the rest with youtube-dl. :)


* SLMR 2.1a * This message brought to you by JAMMITIN (tm)!!

---
■ Synchronet ■ CAPCITY2 * capcity2.synchro.net * Telnet/SSH:2022/Rlogin/HTTP