Error Checking Discs

Programs Needed

ISOBuster
HashCalc

Testing a PS1 CD King's Field disk for errors

• Insert original game disk in PC's drive (won't work with a copied CDR disk).

• In ISOBuster right click on 'Track 01' and select 'Extract Raw data (2352...)".

• When finished, rename track01 and do the above steps a second time.

• Lastly, use any CRC32 tool like HashCalc to measure both Track 01 images; if both have the same CRC, there's a very good chance the disk has no read errors and the image is perfect.

Testing a PS2 DVD King's Field disk for errors

• Insert original game disk in PC's DVD drive (won't work with a copied DVD-R disk).>

• In ISOBuster right click on 'Track 01' and select 'Extract user data...'

• When finished, rename track01 and do the above steps a second time.

• Lastly, use any CRC32 tool like HashCalc to measure both Track 01 images; if both have the same CRC, there's a very good chance the disk has no read errors and the image is perfect.

Additional Information

• You have to 'dump' disks twice because CD drives try to fix read errors by 'guessing' what the data is. If a disk has read errors (from scratches etc), its CRC will come out differently each time you dump it.

• When two disk images have identical CRCs, they are byte for byte identical.

• This will not work from a CDR copy of the game because CD drives will often add junk data to disk images when they burn them or the original source disk might have had read errors. Since the 'junk data' and read errors are permanently burned into the CDR, it will produce a consistent, but bad CRC.

• After you've measured the CRC for your KF games, you can check the values against the list on the Releases and variants page.

• You can dump disk images with programs besides ISOBuster and test for CRC, but some disk 'dumping' software uses rearranged formats or include 'sub channel' data in the disk-image so disk CRC will not be accurate. CloneCD should make an accurate image, but it is not free like ISOBuster.

• Sub channel data is never used on PS1 game disks EXCEPT for some Europe region disks which were protected with LibCrypt (it wrote vital parts of the game's data in the sub-channel as a copy protection). King's Field does not use LibCrypt so the sub-channel data is never used or needed (ie .SUB files etc).