DVD Error Correction Tests

In the following tests we examined the DVD reading capabilities of the Optorite DD0203 drive with scratched / defected 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, in which there are scratches with dimensions from 0.4 to 3.0 mm. The following transfer rate picture comes from CDVD Benchmark v1.21.

The drive gave back read errors as soon as the pickup reached the heavily scratched area of the disc. The reading speed was reduced at 2x throughout the scratched area. The rest of the disc was read at 4x CLV, as you can see from the graph above.

ABEX TDR-825

This is also a single sided, single layer DVD-ROM with a 4.7GB capacity. The data structure of the disc is exactly the same as the TDR-821, with the difference that there not scratches on it but defected areas with dimensions from 0.5 to 1.1 mm. There also fingerprints sized from 65 to 75 micro meters.

This time the disc was read without any read errors. The reading speed was reduced from 10x to 8x in a specific defected area (fingerprint), but reading was normally resumed and the test was successfully finished.

- Dual Layer media

ABEX TDR-841

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

The drive gave back read errors in the heavily scratched areas, in both layers of the disc. This behavior was also noticed in the ABEX 821 reading test, which has the same scratches for a single layer.

ABEX TDR-845

The 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 defected areas and fingerprints. The dimensions of the defected areas are ranged from 0.5 to 1.1 mm and the fingerprints are sized from 65 to 75 micro meters.

As in the corresponding test with the ABEX TDR-825 (defected single layer DVD-ROM), the drive had no problems to finish the task successfully. The reading speed was 4x..

ABEX TDV-541

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

The reading process started at 4x until the 2.4GB address of the test disc, where the drive lowered the speed in order to read the scratched area. Although the first layer was read, not easily however, the second layer was even harder for the drive. CDSpeed gave a read error and the test was terminated, as you can see in the screen shot above.

ABEX TDV-545

The TDV-545 disc is based on the TDV-540 series. It is a single sided, dual layer DVD-VIDEO disc with a capacity of 8.5GB. The TDV-545 includes artificial black dots on the data surface, sized from 0.4 to 1.0 mm. It has also 65 - 75 micro meters fingerprints.

Black dots and fingerprints were not a problem for the drive. The test was successful, with an 4.29x average speed .