Jan Engelhardt
On Thursday 2019-09-05 22:37, Berthold Höllmann wrote:
Jan Engelhardt
writes: On Wednesday 2019-09-04 23:16, Berthold Höllmann wrote:
Jan Engelhardt
writes: On Wednesday 2019-09-04 18:17, Berthold Höllmann wrote:
I did replace the cable now, but that did not fix the problem. I guess it has to do with libdvdread4 or libdvdcss2, I can burn DVD+RW and successfully read the burned data with the same drive.
Well if that is your guess, then you can just copy the DVD with /usr/bin/readcd or /usr/bin/ddrescue to a file, and then the same problem should occur with said file.
Good point. So it is not the libraries, I can open images of DVD Video disks and view the content using vlc and mplayer.
Trying to generate the images on this machine aborts dd_rescue finds only 1073 MBytes, but I can read 4.3GB from DVD+RW disks. What else could be wrong here?
1073741824 = 1024^3
This value does not appear in the CHS and LBA limitations of bygone generations of computer hardware.
But it is a value that .VOB files on DVDs generally do not exceed. In other words, it does not appear you are copying the disc as a whole entity; instead, you are erroneously copying just one file that contains only part of the entire feature.
OK, this is somehow consistent with the fact that libdvdcss2 is only able to determine keys for the first, or first few VOB(s), and fails for the remaining. The DVD player software (or dd*) are only able to read the unlocked VOB(s).
That must simply be untrue. dd* does not care whether the files are locked or not. Unless you have a serious hardware defect (but I more think of it as a layer-7 problem), there is more than 1 GB to be extracted. If the tools are used, properly.
LC_ALL=C dd if=/dev/sr0 of=out.iso
But I think the DVD drive does. I insert a video DVD in the drive and call dd: error reading '/dev/sr0': Input/output error 2352+0 records in 2352+0 records out 1204224 bytes (1.2 MB, 1.1 MiB) copied, 0.384053 s, 3.1 MB/s
mplayer dvd:// ... (lots of keys on this DVD found, lots more of them not found using libdvdcss2) ... dd if=/dev/sr0 of=~/ISOs/Hanna.iso 2097151+0 Datensätze ein 2097151+0 Datensätze aus 1073741312 bytes (1,1 GB, 1,0 GiB) copied, 127,892 s, 8,4 MB/s sudo readcd f=test.iso No target specified, trying to find one... Using dev=4,0,0. Read speed: 16620 kB/s (CD 94x, DVD 12x, BD 3x). Write speed: 4234 kB/s (CD 24x, DVD 3x, BD 0x). Capacity: 3005491 Blocks = 6010982 kBytes = 5870 MBytes = 6155 prMB Sectorsize: 2048 Bytes Copy from SCSI (4,0,0) disk to file 'test.iso' end: 3005491 addr: 3005491 cnt: 51 Time total: 549.278sec Read 6010982,00 kB at 10943,4 kB/sec. ls -lh test.iso -rw-r--r-- 1 root root 5,8G 6. Sep 00:57 test.iso
This is the actual sequence of the commands. So in some way libdvdcss2 unlocked the DVD drive in some way, and dd did not read the whole disk.