4-5 September 2012 Vietnam Film Institute Workshops 1

Digital Preservation Strategy

Choices when moving Choices when moving analogue to digitalanalogue to digital

Choices in the digital Choices in the digital worldworld

Supporting choices with Supporting choices with good cost estimatesgood cost estimates

4-5 September 2012 Vietnam Film Institute Workshops 2

Roadmap

Where am I, where do I go next Audio: only one answer: uncompressed to .wav

file; some options 16-bit bit depth, or could go for “24” CD sampling rate= 44.1 kHz; or 48 kHz or 96 kHz BWF = Broadcast Wave Format version of .wav

4-5 September 2012 Vietnam Film Institute Workshops 3

Video Roadmap

The basic problem: uncompressed video is 200 megabits per second = 100 gigabytes per hour

VHS quality is roughly 1 megabit/sec (AVC = H.264 = MPEG-4)

DVD quality is roughly 5 megabits/sec (MPEG-2)

So: hard to justify saving poor-quality video as uncompressed video at 200 Mb/s

Compromise: “temporary archiving” in a compressed format “for a few years”

4-5 September 2012 Vietnam Film Institute Workshops 4

Video Roadmap

http://wiki.prestospace.org/pmwiki.php?n=Main.Roadmap

Clear statement for archived standard definition video

Input: Low, Medium and High Quality originals

Output: Access copy or Preservation copy

Access: DVD disc or MPEG-4 file

Preservation Roadmap:

Low: VHS, compressed digital DV file, 25 Mb/s

Middle: U-Matic, DV DV file

High: BetaSP, Digibeta, other pro formats uncompressed or lossless compressed (JPEG2000)

4-5 September 2012 Vietnam Film Institute Workshops 5

Video Roadmap

Much less clear for high definition video Many production formats Various kinds of “HD” But:

Interlaced video should be saved as interlaced Saving the 'native format' is ALWAYS good Saving uncompressed remains a problem BBC is promoting VC-2 codec (simpler than J2K)

4-5 September 2012 Vietnam Film Institute Workshops 6

Too Many Video Formats !

The following are supported by one file converter (Total Movie Converter):

Audio Video Interleaved (.AVI) Windows Media Video (.WMV) DivX Video (.DIVX) XviD Video (.XVID) DVD Video (.VOB) Digital Video (.DV, .DIF) Apple QuickTime Video (.MOV) MPEG Video (.MPG, .MPEG, .MPE, .M1V, M2V, .MPV) MPEG4 Video (.MPEG4, .M4V, .MP4) Advanced Streaming Format (.ASF) AVS Video (.AVS)

4-5 September 2012 Vietnam Film Institute Workshops 7

More !

Intel Indeo Video (.IVF) Matroska Video Stream (.MKV) Mobile Phone Video (.3GP, .3G2) HD Video (.H261, .H264) JVC Digital Video (.MOD) WinAmp3 Video (.NSV) MythTV Video (.NUV, .NUT) Flash video (.FLI, .FLC, .FLX, .FLV, .FFM, .SWF) Sony high definition video (.MTS and .M2TS) RealMedia Variable Bitrate (RMVB) Telesync (TS)

4-5 September 2012 Vietnam Film Institute Workshops 8

Recommended for Video

Professional: MXF; does everything Alternatives: MOV (Quicktime), AVI

But: AVI does not support timecode

And then: how do you store your files: Hard drives Data tape (LTO and a few others) Optical media: CD, DVD

4-5 September 2012 Vietnam Film Institute Workshops

File Formats for Film

DPX uncompressed, very flexible DCI DCDM = Digital Cinema Distribution Master:

2048x1080 (or 4096x2160) only DCP = Digital Cinema Packaging = lossy compressed

JPEG200; (not for master) JPEG2000 (lossless); 2:1 data reduction Various lossy compression formats (avoid!) And … various wrappers: MXF, AVI ...

MXF (same as used in broadcasting – except there are many versions of MXF)

4-5 September 2012 Vietnam Film Institute Workshops 10

Migration of File Formats

Is the fo rm at a p rob lem?

S TA R T H E R E

Arch ive fo r a few years

W hat cost/qua lity/risk op tion can you a ffo rdC om press

lossy

Y E SN O

U ncom pressC om press lossless

E N D H E R E

(1 )

(2 )

(3 ) (4)

(5a)(5b)

(5c)

4-5 September 2012 Vietnam Film Institute Workshops 11

Preservation Strategy

Keep what you have as long as it works Migrate to a new format when the old format

has a problem (usually, obsolete) Examples: Real Audio, MPEG-1 Video

OR – maybe you can emulate the software needed to use the file, even after standard software no longer works University of Liverpool: Multivalent Browser

4-5 September 2012 Vietnam Film Institute Workshops 12

Strategy with Emulation

Is th e fo rm a t a t risk?

START HERE

A rch ive fo r a fe w ye a rs

W h a t co s t/q u a lity/risk ca n

yo u a ffo rd?C o m p re ss

lo ssy

YESNO

U n co m p re ssC o m p re ss

lo ss le ss

END HEREMultivalent

4-5 September 2012 Vietnam Film Institute Workshops 13

Storage Options

PrestoPRIME has lots of white papers And tools for 'what-if' analysis of storage systems:

How many copies do I need? Should I buy more discs, or use data tape backup? How often should I check the files?

Will give more detail on storage tomorrow

4-5 September 2012 Vietnam Film Institute Workshops

A Preservation Model

4-5 September 2012 Vietnam Film Institute Workshops 15

Demonstration: Tools for Understanding Storage

PrestoPRIME Online Tools

http://prestoprime.it-innovation.soton.ac.uk/

http://prestoprime.it-innovation.soton.ac.uk/

4-5 September 2012 Vietnam Film Institute Workshops 16

End of Day One !

Thank you all Tomorrow:

Storage and storage systems Software for a file-based archive Access

All the problems All the opportunities

General Summary and Discussion