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The dvdread utility allows you to create deCSSed image of protected
DVD. What you do with the resulting image is your own business, not
Sony's or Some Other Guy's one. If you attempt to read scrambled DVD
directly with cp/dd/readom, you'll get I/O error (Read of scrambled
sector without authentication) on all scrambled sectors and any
workarounds like dd_rescue will just produce damaged MPEG.

dvdread depends on libdvdcss (http://download.videolan.org/libdvdcss/)
and libdvdread (http://dvdnav.mplayerhq.hu/#download) libraries. To
build dvdread on Debian GNU/Linux system you need to install
libdvdread-dev package from main repository and libdvdcss-dev one from
www.deb-multimedia.org.

Example usage:
./dvdread /dev/sr0 >akira_decss.iso
mplayer -dvd-device akira_decss.iso dvdnav://menu

Dvdread looks for DVD region restriction mask inside the VIDEO_TS.IFO
and VIDEO_TS.BUP files and resets it to 0xC0 if it's not zero and
doesn't equal to 0xC0 already. This means that the produced deCSSed
image file can be written onto DVD-R/RW media and the resulting disc
should be playable in any region.

dvdread prints progress and error messages to stderr and dumps deCSSed
stream to stdout. If you want to debug, run it with DVDCSS_VERBOSE
envvar, e.g.:
DVDCSS_VERBOSE=2 ./dvdread /dev/sr0 >/x/y/z

dvdread Operation

1. dvdread uses libdvdcss to authenticate itself to DVD drive using
   special IOCTLs, and this eliminates "Read of scrambled sector
   without authentication" errors.

2. These scrambled sectors must still be descrambled (deCSSed)
   afterwards, using correct Title Key. dvdread uses libdvdread to
   locate start-end sectors for all titles on disk and re-issues
   DVDCSS_SEEK_KEY when entering corresponding sector areas (resulting
   in single DVDCSS_SEEK_KEY operation per title). If you do
   DVDCSS_SEEK_KEY for each sector instead, ripping will be way too
   slow.

dvdread Problems

1. dvdread doesn't reset UOP restrictions
   (cf https://en.wikipedia.org/wiki/User_operation_prohibition).

2. dvdread may fail due to region mismatch. For some DVDs you may be
   able to rip using wrong region and for some you may not. This
   happens because drive refuses to decrypt title keys for mismatched
   region and libdvdcss attempts to crack title keys itself. Cracking
   depends on plaintext content and doesn't always work:

sector 2009702: libdvdcss debug: getting title key at block 2009702 the classic way
libdvdcss debug: requesting AGID
libdvdcss debug: drive authenticated, using variant 0
libdvdcss debug: authentication established
libdvdcss debug: ioctl ReadTitleKey failed (region mismatch?)
libdvdcss debug: GetASF not authenticated, ASF=0
libdvdcss debug: lost ASF requesting title key
libdvdcss debug: resetting drive and cracking title key
libdvdcss debug: requesting AGID
libdvdcss debug: ioctl ReportAgid failed, invalidating AGID 0
libdvdcss debug: requesting AGID
libdvdcss debug: drive authenticated, using variant 0
libdvdcss debug: authentication established
libdvdcss debug: GetASF authenticated, ASF=1
libdvdcss debug: decrypting disc key 7d:8b:c2:73:bd
libdvdcss debug: trying player key 01:af:e3:12:80
libdvdcss debug: decrypted disc key is 00:77:36:36:ee
libdvdcss debug: cracking title key at block 2009702
libdvdcss debug: at block 2013798, still cracking...
libdvdcss debug: at block 2017894, still cracking...
libdvdcss debug: at block 2021990, still cracking...
libdvdcss debug: at block 2026086, still cracking...
libdvdcss debug: at block 2030182, still cracking...
libdvdcss debug: at block 2034278, still cracking...
libdvdcss debug: at block 2038374, still cracking...
libdvdcss debug: non MPEG block found at block 2038483 (end of title)
libdvdcss debug: end of title reached
libdvdcss debug: successful attempts 0/0, scrambled blocks 13734/28781
libdvdcss debug: title key is 00:00:00:00:00
libdvdcss error: fatal error in vts css key