DVD Error Correction Tests

In the following tests we examined the DVD reading capabilities of the SONY DRU-530A drive with scratched / defective DVD media. For the tests we used CDVD Benchmark and Nero CDSpeed. The reference test media come from ALMEDIO.

- Single Layer media

ABEX TDR-821

This is a single sided, single layer DVD-ROM with a 4.7GB capacity, and its surface has an artificial scratch of dimensions varying from 0.4 to 3.0 mm. The following transfer rate picture comes from the CDVD Benchmark v1.21 transfer rate test.

The drive read the 821 test disc without reporting any reading errors. There were no speed deviations while reading the defective areas on the disc's surface. The only setback is the rather slow reading speed (4x), especially when we consider that other drives accelerate up to 12x with DVD-ROM media.

ABEX TDR-825

This is also a single sided, single layer DVD-ROM of 4.7GB capacity. The data structure of the disc is exactly the same as that of the TDR-821, with the difference that there are no scratches on the surface and instead defective areas ranging in dimensions from 0.5 to 1.1 mm. There are also fingerprints with height between 65 and 75 micrometers.

The drive managed to read the defective areas on the disc without problems. Once again the reading speed was slow at around 4x.

- Dual Layer media

ABEX TDR-841

This is an 8.5GB dual layer, single sided DVD-ROM disc with artificial scratches of dimensions ranging from 0.4 to 3.0mm, on both layers.

Although the drive began normally, slowly accelerating from 4x up towards the 8x mark, a little after the half way point into the first defective region on the disc, the speed dropped back down to 4x and kept at this speed up until the end of the test. No read errors were reported.

ABEX TDR-845

This disc is a single sided, dual layer DVD-ROM disc with a capacity of 8.5GB. The only difference between the TDR-845 and the TDR-841 is that the first includes both defective areas and fingerprints. The dimensions of the defective areas range from 0.5 to 1.1 mm and the fingerprints have height sized from 65 to 75 microns (micrometers).

Both layers were read at approximately 4x. The defective areas did not pose a problem for the drive.

ABEX TDV-541

The TDV-541 is a single sided, dual layer DVD-VIDEO disc, with a capacity of 8.5GB.The disc is based on the TDV-540 series which is designed for inspection and adjustment of DVD-VIDEO players. The disc checks the layer switch operation from layer 0 to layer 1 and also includes test pictures and test signals for DVD sound files. The current TDV-541 also checks the error correcting capabilities of the drive and includes scratches sized from 0.4 to 3.0 mm.

The drive read the TDV-541 test disc without reporting any errors. However we have a similar phenomenon here as we had when reading the TDA-841 ABEX disc where the speed accelerated and then dropped back to 4x, keeping that speed up until the end. The disc was readable, however, with some problems in the beginning of the second layer. Playing the disc through PowerDVD confirmed that both layers were readable.

ABEX TDV-545

The TDV-545 disc is based on the TDV-540 series. It is a single sided, dual layer Video/S-2 disc with a capacity of 8.5GB. The TDV-545 includes artificial black dots on the disc's surface, sized from 0.4 to 1.0 mm. It also has 65 - 75 micrometer high fingerprints.

This disc seems to be no problem for the Sony drive. The black dots and fingerprints were bypassed without any effort.