Blu-ray
The process – Blu-ray authoring (preparation of an animated menu – graphics, sound, language versions) may be performed in standard content or advanced content versions. Preparation of authoring in the standard option is a slightly more extended version of what is applied in the case of DVDs. Advanced content makes use of a special programming language called iHD, thanks to which all interactive functions are created, together with the option of playing back two video streams simultaneously.
Blu-ray variants:
• BD-Rom, read-only type disc, applied for game programming and film distribution,
• BD-R type recordable disc, applied in storing HDTV images and data,
• BD-RE, re-recordable disc, used in storing HDTV images and data.
Please find below comparisons of the technical capabilities, but only for pressed discs (read-only), as the parameters for R/RW versions evolve quickly.
|
The types of discs
|
DVD
|
Blu-ray |
|
Format
|
DVD-Rom
|
BD-Rom |
|
Disc size
|
120 mm
|
120 mm |
|
Disc structure
|
0,6 mm x 2
|
0,85 mm x 2
|
|
Number of layers
|
1 or 2
|
1 lub 2 |
|
Capacity
|
4,7 GB/8,5 GB
|
25 GB/50 GB |
|
Length of laser wave
|
650 nm
(red laser) |
405 nm (blue-violet laser) |
|
Compression technology
|
MPEG-2
|
MPEG-4 AVC/
VC1/MPEG-2 |
|
Time of pressing 1 unit
|
1,7 - 2,5 s
|
3,8 s |
|
Track pitch
|
0,74µm
|
0,32µm |
From the point of view of the user, it is useful to know that DVDs also play on HD DVD and Blu-ray players, but you can’t watch a VCD on a Blu-ray and HD DVD players.