DVD Error Correction tests

In the following tests we examine the DVD error correction capabilities of Toshiba SD-R5002. For the tests we used CDVD Benchmark v1.21 and Nero DVD Speed . The reference test media comes 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 2.6 to 4.8 mm. The following transfer rate picture comes from CDVD Benchmark v1.21.

Toshiba SD-R5002 seems to have no problem finishing the reading task with no errors. The graph is not interrupted, meaning that the drive read the disc smoothly and no errors were reported. The performance is really high revealing high error correction capabilities.

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 6.5 to 7.5 mm.

The drive read the disc smoothly until the middle of the last defected area (fingerprint). The reading speed was reduced to 2X with no errors, however, reported. The yellow dots correspond to the current speed in each area of the disc.

- 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 48 mm, in both layers.

The result is very good, as it was expected, judging from the reading test with the single layer disc. If you compare the two yellow transfer lines with the one we had in the TDR-821 test, you will see that the drive showed a similar good reading behavior, in both layers.

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 0.065 to 0.075 mm.

Again the drive easily overcomes the defected areas and successfully finishes the reading test. Notice that in the first layer, the accurate reading speed in the scratched area is not clearly defined, due to the drive attempts to read accurately the specific data.

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 1.8 to 3 mm.

The drive supports 4.8X CAV average reading speed for the DVD-Video format, but the test showed that the reading speed by the end of the first layer reached the 8X. The scratched areas made the drive slow down momentarily but it seems that there were no reading problems. The average reading time was 6.24X and the average random seek time time 117 msec.

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 0.8 to 1.0 mm. It has also 0.065 - 0.075 mm fingerprints.

Black dots and fingerprints were not a problem for the drive. The test was successful, with an 6.29X average speed and 116 msec for the average random seek time.