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Use the dd command to image 'damaged' CDs UNIX
I'm using a non-Apple DVD-RAM drive, that worked perfectly until upgrading to 10.3. Now, when I go to copy a CD (music or otherwise) with Disk Utility, I verify the disk with the Verify button, and _most_ (but not all) of my CDs come back with the error:
Master Directory Block needs minor repair
The volume Program Disc needs to be repaired.

1 volume checked
0 HFS volumes verified
1 volume needs repair
For a week or so, I just thought that most of my CDs were bad. Then I thought of using the dd command in the Terminal.app. My line:
dd if=/path/to/InputFile of=/Path/to/OutputFile bs=2048
What I get from this is an ISO file that works perfectly. For further info, run /usr/bin/man dd. It seems like there are some sensitivity issues, with 10.3, the drive, or both. Hardly any of my CDs have any physical flaws, which is what brought me to try dd. I hope this helps someone out there.
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Use the dd command to image 'damaged' CDs
Authored by: wcattey on Jan 11, '04 07:07:21PM

I received a DVD home movie from a friend with a PC.
He had burned consumer format (VIDEO_TS et al) onto a DVD+R disk.
The disk would not play in my consumer player, and would
read on my Panther iMac, but would not reliably play with the DVD Player App.

I attempted to use this hint to make a copy onto Apple DVD-R media (which my consumer player likes just fine.)

What I probably SHOULD have done was used Disk Utility to make an image copy, and then used Disk Utility to burn the image. (But I'd momentarily spazzed and forgotten to try that.)

dd if=/Volumes/myDVD of=myDVDcopy.img bs=2048
did not work. It created a file which was the mount point, not the data.

I saw that /dev/disk1 was mounted on that mount point.

dd if=/dev/disk1 of=myDVDcopy.img bs=2048
did not work. It complained that disk1 was busy.

Going into Disk Utility and unmounting myDVD, and THEN
dd if=/dev/disk1 of=myDVDcopy.img bs=2048
worked! Then I ejected the DVD using Disk Utility.
I then used Disk Utility to burn myDVDcopy.img onto Apple
DVD-R media which my consumer player indeed played just fine.

I won't say Disk Utility works for image copy of DVD's until I try it. In this case, I thought the list would benefit from my experience using dd for DVD, and how I had to amend the instructions to get them to work.



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