Back up copyright-protected DVDs as MKV using DVD Shrink, MakeMKV and ffmpeg
Many DVDs in my movie collection have degraded with age, so it’s time to back them up to a more reliable storage medium before they fail completely. ImgBurn, which has been my tool of choice for handling optical disks over the past decade, complained that these disks have been copyright-protected and refused to proceed:
In the screenshot above, CSS (Content Scramble System) and CPPM (Content Protection for Prerecorded Media) are encryption methods introduced in the late 1990s to prevent unauthorized copying of copyright-protected DVDs. Unlike the strong encryption schemes nowadays which are usually 256 bits, CSS and CPPM are merely 40-bit and 56-bit, respectively, and have long been cracked. Even without cracking these encryption schemes, the idea behind DVD encryption is flawed as the encryption key must also be distributed with the DVD player, which would otherwise not be able to decrypt the DVD. Even back in the days, it wasn’t long before applications capable of reading these copyright protected DVDs using leaked encryption keys became available. Among these applications, my favorite is DVDShrink 3.2.0.15, a very simple software which was designed for Windows 98 but still worked well on Windows 11:
Unlike ImgBurn, DVD Shrink does not care about copyright-protected disks and will happily open any disks after spending just a few seconds scanning the disk content. To rip a DVD into an ISO file without losing quality, change the Compression dropdown from Automatic to No compression. Under Edit > Preferences, change Target DVD size to DVD-9 (8.5GB):
After that, select File > Backup, choose ISO Image File as backup target, choose the path to save the ISO file and click OK. DVD Shrink will then generate an ISO image for your DVD, which will take around 20 minutes. Once done, verify that the ISO file size is around 8.5GB (for a double-layer DVD) or 4.7GB (for a single-layer DVD) and check that VLC can open the DVD, show the episode menu and play all episodes normally.
If you are like me and prefer to play each DVD episode individually from Windows without going through the DVD episode menu, you might want to extract each episode as an MKV file. Just download MakeMKV, open the ISO file and select the titles to be extracted. You might also want to review the settings for Minimum title length (seconds) under View > Preferences, which will prevent short titles from being extracted, as these titles usually contain DVD graphics or useless commercials:
A 45-minute episode will consume around 1.4GB of disk space in MKV format, which uses MPEG-2 video codec and AC3 audio (default for most DVDs), as shown in VLC’s Media Information popup. MakeMKV will also conveniently extract subtitle tracks and secondary audio tracks if available in the DVD ISO image.
Converting the video codec to MPEG4 (H264) using FFmpeg while keeping the audio/subtitle tracks as-is will reduce the file size by around 50%:
ffmpeg.exe -i input.mkv -map 0 -c:v libx264 -crg 23 -preset medium -c:a copy -c:s copy output.mkv
On my laptop with an Intel i7-13700H, 32GB of RAM, and 512GB NVMe storage, the above FFmpeg command which uses the medium preset takes about 4 minutes to convert a 45-minute MKV episode, producing a high-quality output with no noticeable loss in quality. Take note that there are various ffmpeg builds for windows – for the above command to work, you should use a static build that supports H264 codec.
Once the video has been converted, verify that MPEG4 is displayed in VLC’s Media Information popup and that the converted file plays properly before deleting the original file:
With the above steps of combining DVD Shrink, MakeMKV and FFmpeg, you can efficiently back up your copyright-protected DVDs as high-quality MKV files for long-term storage and easy access.
