preserving

materials

what are

materials?

audiovisual

are surrogate

history

2’’ Quad (1956)

TCR 100 Quad (1969)

UV 340 (1964)

Panasonic video

cartridge (1969)

Philips video

recorder (1970)

U-Matic(1971)

V-Cord (1972)

Betamax(1975)

VHS (1976)

D-2 (1988)Hi8 (1989) Digital betacam(1993)

Digital –S (1995)

-2 (1988) Hi8 (1989) Digital betacam(1993)

-2 (1988) 1992

-2 (1988) 1997 : RM

-2 (1988)VOBASF

2001-present

OCG MP4FLV MOVMKV 3GP

in

digital

signal

recording of a signal onto a carrier

digitization

digital preservation of the digitized signal

via

you

computer playback device

video cassette recorder

LEFT: The Avid Dazzle Video Creator Plus HD ($89/P4500) captures video. RIGHT: Pinnacle’s Studio MovieBox HD ($100/P5000) is a similar capture device.

LEFT: The Avid Dazzle Video Creator Plus HD ($89/P4500) captures video. RIGHT: Pinnacle’s Studio MovieBox HD ($100/P5000) is a similar capture device.

LEFT: The Avid Dazzle Video Creator Plus HD ($89/P4500) captures video. RIGHT: Pinnacle’s Studio MovieBox HD ($100/P5000) is a similar capture device.

LEFT: The Avid Dazzle Video Creator Plus HD ($89/P4500) captures video. RIGHT: Pinnacle’s Studio MovieBox HD ($100/P5000) is a similar capture device.

LEFT: The Avid Dazzle Video Creator Plus HD ($89/P4500) captures video. RIGHT: Pinnacle’s Studio MovieBox HD ($100/P5000) is a similar capture device.

properties

resolution-number of pixels present in the images of the

video-determines whether your video is standard

definition or high def.

size-pixel dimension of the frame

aspect ratio-Ratio of width to height

frame rates-speed at which the frames are captured and

intended for playback

bit rate-or data rate-amount of data used to describe the video portion of the file

bit rate-typically measured in per second units then in KB,MB,GB-higher bit rate, better quality (in general)

codec

properties

sampling rate-how often the audio is sampled when converted

from analog to digital

number of channels

Either coming from single (mono) or multiple channels (stereo)

codec

what is a

container VS codec

Describes structure of the file

Short for coder/decoderCompressor or decompressor

-Way of encoding video into a stream of bytes-Chief determinator of quality

…

Container as the file itself.Codec as its contents.

Impt. to realize:-most good container formats can hold many codecs

Describe both!

Example:MOV file containing H.264 data

Problem:

Common use of terms Confusion and imprecision

Even more confusing:-both describes codec and container

Example:“mpeg-4”

Windows media video

-can be streamed across the internet-when WM server: viewed before entire file-windows media player-internet streaming server

Audio video interleave

-Windows Player (ex. WMP)-uncompressed: high quality video-internet: entire file must be downloaded-stored on local hard disk or CDROM

Apple Quicktime Movie

-Apple Quicktime Movie Player-viewed before entire file-streamed across internet-depends on compression

Motion Picture Experts Group

-provide VHS quality movies or better-MPEG player-entire file must be downloaded

-Mpeg1 = VHSMpeg2better than VHS; used for DVDMpeg4best quality

Real Media

-RealPlayer-viewed before the file-high compression but at a cost to quality

-makes a file smaller-decoded file is unaltered after decompression has taken place-by using a scheme known as “run length encoding”

Example:

-Animation codec (which is typically used for archiving or transferring files), have a low compression ratio

-Usually, it’s no more than 2:1.

-you lose some image, video, or audio information. -bit tricky because good lossy compression is a balancing act between quality, data rate/file size, color depth, and fluid motion-Almost every video compression scheme is lossy

-Lossy compression schemes like H.264 (used on Canon video DSLRs) can have compression ratios of more than 100:1.

-With video workflows, compression can be applied (or removed) at several stages.