DVD stands for Digital Versatile Disc. It is suitable for data backup purposes and good quality video storage. It is available in pressed DVD-ROM, DVD-R, DVD+R, DVD-RW, DVD+RW and rewritable DVD-RAM (Matsushita\Panasonic) in single layer (4.7Gb) and dual layer (9.4Gb) formats.
Total maximum data rate: 9100 kbits/sec=9318400 bytes/sec
Audio: 320 kbits/sec=327680 bytes/sec
This means and average of 9318400/25=372736 bytes per frame for video.
Audio will usually be encoded in AC3 or Dolby 5.1. Audio is rarely encoded
in uncompressed linear PCM format except in some high quality DVDs.
If video at that resolution is stored in as uncompressed 24-bit RGB values that would require
For video: 720*576*25*3=31,104,000 bytes/sec
For audio: 44.1kHz, stereo, 16bit = 44100*2*2=176400 bytes/sec
=31,280,400 bytes per second in total uncompressed.
This means that the compressed data on DVD takes up a fraction of the uncompressed data.
That gives us a 70.2101% saving!
The video compression techniques used by DVD are 16*8 macroblock encoding, intra-frame GOP generation, colour quantization, DCT encoding and at the lowest level Huffman encoding.
DVD-Video provides excellent picture and sound quality at a good price for films.
The DVD-Video coding scheme allows basic interactive menus, multiple language and subtitle support, commentary soundtracks all on even the most basic disks. DVD-Video is good for archiving vintage material from VHS using commonly available set top boxes and PC based authoring software.
DVD in general is a very versatile and affordable way to archive data.
There is a variety of good DVD writing software and DVD-Video authoring tools available for the home user.
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