Crack the disc encryption: copy a large DVD to the hard disk

When VCD became popular a few years ago, we often copy files under the Mpegav directory in the VCD to the hard disk. This not only reduces the wear and tear of the optical drive, but also ensures smooth playback of the VCD. Now, when we play a DVD, the DVD drive is even more busy. If we can take some time to copy the content on the DVD to the hard disk for playback, can we free up the hard work of the CD? Can I directly use the copy method applied to VCD on a DVD?

1. Direct Copy Method

When I first introduced the knowledge of DVDs, all the audio and video files and subtitles on the DVDs are stored in the VOB file under VIDEO_TS, while the IFO file is an important file used to control VOB playback, the BUP file is the backup file of the IFO file, which plays an alternative role when the IFO file cannot be read. Therefore, in principle, as long as we copy the entire VIDEO_TS folder from the CD to the hard disk, it should be able to play directly.

The copy and paste operations are unnecessary here, but the copy time varies depending on the multiples of the DVD drive and the volume of the DVD drive. How do I play a DVD copy to a hard disk? Take PowerDVD as an example. After starting PowerDVD, click the "select Source File" button on the panel and select "Open DVD film on hard disk" (1) in the pop-up menu ), then, in the pop-up path selection dialog box, specify the folder of the copied DVD Video to play normally, which is no different from playing on the CD.

Figure 1 playback of files on Hard Disk

Ii. decrypt and copy again

When using the direct copy method, we will find that many DVDs do not allow us to copy the DVD files to the hard disk at will, and some cannot play normally even if they can be copied, this is about the encryption of the DVD.

Generally, a DVD uses an encryption method named CSS (Content Scrambling System, an irregular Content System) to prevent attempts to directly read multimedia files from the disc without decryption keys. However, encryption means decryption and DeCSS. DeCSS was developed by MoRE (Master of Reverse Engineering), a Norwegian technology development organization. It can obtain an effective decryption key and easily copy encrypted DVD files. This copy stores all extended VOB files in the hard disk for decryption. Because the video is not encrypted during playback, the files stored on the hard disk are not encrypted.

With DeCSS technology, we can copy a DVD disc to a hard disk regardless of whether it is encrypted or not, but the software that uses DeCSS technology needs to be used to encrypt the copy of the DVD. The software in this area includes DeCSS1.21b, CladDVD, De-MPAA, SmartRipper 2.41, and DVD Decrypter. We use the DVD Decrypter as an example to describe the operation of decryption and copying.

Install and start the DVD Decrypter (2). We can complete decryption and copy in three steps.

Figure 2 main DVD Decrypter Interface

1. Select a paragraph or file

In the default mode, the Decrypter mode automatically analyzes the IFO file in the DVD Disc and displays each file, film, and paragraph at the first place on the right. Click the check box to select the corresponding file.

If you are not familiar with this method, you can select "Mode> File" from the menu, and the style shown in 3 is displayed on the right of the window. This mode displays all the VOB, IFO, and BUP files on the DVD. You can press Ctrl and Shift to select multiple files. Based on our previous analysis, select the VOB file and the corresponding IFO file.

Figure 3 DVD Decrypter file Mode

2. Set the Save path

In Destination of 2, set the Save path.

3. Copy to Hard Disk

Click the Decrypt button in the lower left corner to Decrypt and copy the selected file to the hard disk. During the copy process, we can also see the copy progress in the pop-up status window, for example, the storage location of the target file, the size of the file to be copied, the copy rate, the used time, and the remaining time (4). If you click Cancel, it can also stop the replication process.

Figure 4 copy progress

Tips

In addition to directly copying a DVD disc, the DVD Decrypter also has multiple features, such as using any DVD disc as an image for some virtual optical drives.