Extracting the boot image from a CD/DVD. If you need to extract a boot-image from a CD/DVD (El Torito) you can simply use this program.

The usage of BootExtract is simple. You only need to pass the drive-letter of the CD-ROM/DVD to the program. Alternatively, you can pass a filename to an ISO-image. Here is an example of the usage, if your CD-ROM/DVD-drive is F: then:
BootExtract f:

This will store the boot-image in the current directory with the name Drive-f.NoEmulation__Segment-0000__SecCount-4.bin. The filename always contains the following elements (which can be used to write this boot-image with a burning-program like Nero):
1. Drive-f: Specifies either the drive-letter of the CD/DVD-ROM or the ISO-filename.
2. NoEmulation: The mode which is used by this boot-image. The possible modes are:
* NoEmulation
* 1.2MegDisk
* 1.44MegDisk
* 2.88MegDisk

3. Segment-xxxx: The segment which will be stored in the initial-entry for this boot-image (normally 0000 or 7C00).
4. SecCount-y: The number of virtual sectors (512 bytes) used for this boot-image.

The complete usage-description is here:
CD/DVD-BootImage-Extractor v1.0 (c) Jochen Kalmbach
blog.kalmbachnet.de/

Usage: BootExtract [switches] <source>
* source: The source file (*.iso) or CD/DVD-drive to extract images from
* switches: -b Also extract bootrecord and bootcatalog

Examples: BootExtract z:

The following defines need to be known (which are stated in the spec):
1. CD-sector-size: 0x800 bytes.
2. Virtual-sector-size: 0x200 bytes.
3. Sector-number of the boot-record-volume: 0x11.

Now, you can read the initial/default boot-image if you do the following:
1. Read the boot-record-volume (sector 0x11) and check for validity.
2. Extract the sector-number from the boot-record-volume which contains the boot-catalog (DWORD at byte-offset 0x47).
3. Read the boot-catalog (from the above extracted sector number) and check for validity.
4. Extract the boot-information from the Initial/Default-Entry in the boot-catalog (starting at byte-offset 0x20 in the boot-catalog).
5. Extract the starting-sector (DWORD relative byte-offset 0x8) and the virtual-sector-count (WORD at relative byte-offset 0x6) for the boot-image from this entry and read the boot-image.

The license of this software is Freeware, you can free download and free use this boot cd software.