Document Formats

8/6/2019 Document Formats

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Document Formats

and Image Formats

James C. KingPDF Architect/SeniorPrincipal Scientist

Advanced Technology LaboratoryAdobe Systems Incorporated


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Outline

Some Fundamentals

PDF Documents

PDF Pages

Synthesized Pages versus Scanned Pages

PDF and JPEG2000

PDF and ISO Standards


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Some Fundamentals


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Image Formats versus Document Formats

picture

Multi-page Compound Document(e.g., PDF)

Sampled Image(e.g., JPEG2000)

picture


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Image Sampling (JPEG2000)

display or page

(arbitrary image size)

JPEG2000 Image

(multiple resolutions)

supersample

subsample

Sub and Super Sampling Tools needed Size and resolution are diferent things


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PDF Documents


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PDF: Multi-page Compound Documents

A Comprehensive Format or Representing Documents and Forms

Not an image ormat like TIFF or JPEG

High delity, high precision text layout and graphics eatures Platorm and device independent denition

Selective compression to reduce le size (e.g., image ormats)

Color Management (ICC support)

Page contents Images Graphics Fonts Colorspaces

Metadata Annotations Links Digital signatures

PDF 1.0 in 1993 PDF 1.7 in 2006. Many enhancements!


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Composite Documents


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PDF Pages

Page Content Objects


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Text, Graphics and Image

Typographic Text

Vector Graphics

Sampled Images

Typographic Text


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2 0.8 0.7 2 10 210 cm

2.5 0 0 -1 235 170 cm

3 0.9 0.8 1 180 200 Tm

Text

Coordinate Transorms

x-scale, rotate/skew, rotate/skew, y-scale, x-pos, y-pos


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Clipping and Masking

Typographic TextTypo

picture

Clip to path (star) Mask of sky

Mask

Picture


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Text as Text

Text as text

(using outline onts) Text as image

The JPEG2000 image compressiontechnique has been cited by experts

as a new archiving ormat or digital

images. It is both a preservation and

delivery ormat, and has been seenas a possible alternative to the TIFF

ormat which most institutions use

as a long-term archiving standard.

Produced by both imaging experts

and the Joint Photographic ExpertsGroup, it is now a recognised ISO

standard. The standard JPEG fle

ormat which is so widely in use is

not yet an ISO standard.


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Resolution Independence


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Resolution Independence


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Synthesized Pagesversus

Scanned Pages


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Document Sources

Born digital More compact

Editable

Device independent/resolution independent Zoom-able

Scanned rom paper

Bulky Need to pick a sampling resolution

Text and image need diferent treatment

Can do OCR or DR (document recognition)

Born digital is a luxury


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OCRed Text as Underlayer

OCRd Text

underlaid

made invisible

may have mistakes

used for searchScanned Text as Image

A PDF Page


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Image Text and Image Picture Require Diferent Treatment

The JPEG2000 imagecompression technique has beencited by experts as a newarchiving format for digital

images.

The standard JPEG file format

which is so widely in use is notyet an ISO standard.

Needs 1-bit per pixel black and white at 600 dpi

Needs 24-bit per pixel color at 150 dpi

MRC (Mixed Raster Content)

Both JPEG2000 and PDF support this


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PDF and JPEG2000


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PDF Support or JPEG2000

JPEG2000 images can be included on PDF pages

JPX Baseline is supported

Enumerated color spaces 19 (CIEJab) not supported

Enumerated color space 12 (CMYK) is supported

All our progressions supported: resolution, color depth, band, location

Inappropriate progression will just cost time

One global sot mask within the JPEG2000 supported JPEG2000 document eatures are not supported

PDFs document eatures are more general and more exible

An image to display in a rectangle is obtained rom the JPEG2000 stream


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Sotware Support

Key to use o any image ormat or document ormat are the tools available

Tools or creation

support advanced eatures

Tools or presentation

Tools or incorporating with other ormats

Ubiquity o viewing tools

OCR and DR capabilities


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PDF andISO Standards


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Establishing the ISO PDF Umbrella

PDF 1.7 (ISO 32000 in 2008

PDF/Aarchive

ISO 19005-1(PDF 1.4)

PDF/Eengineering

AIIM Committee--> ISO

PDF/UAaccessibility

AIIM Committee--> ISO

PDF/Xgraphic arts

ISO 15930-1(PDF 1.4 & 1.6)


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PDF/A

A PDF subset or archiving

ISO 19005-1

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Long-term Preservation Needs or Electronic Documents

Characteristics identied as objectives or PDF/A were Device Independent - Can be reliably and consistently rendered without regard

to the hardware or sotware platorm

Sel-contained - Contains all resources necessary or rendering

Sel-documenting - Contains its own description

Unettered - Absence o technical le protection mechanisms

Available - Authoritative specication publicly available

Adoption - Widespread use may be the best deterrent against preservation risk

PDF/A -- A PDF Subset o PDF 1 4


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PDF/A -- A PDF Subset o PDF 1.4(Standard: ISO 19005-1)

Some useul PDF eatures work against, and are incompatible with,preserving inormation over the long-term

PDF/A

PDF Subset: restricted rom using some PDF eatures, or example Anything that would alter the visual appearance over time (orms)

No external reerences or embedded les

Encryption

PDF Subset: required to use some PDF eatures, or example

Accessibility eatures or recoverable text (tagged PDF)

Embed all onts

Specic metadata requirements

Device independent color


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Uses or PDF/A

Archival storage o electronic documents

Documents o record

Government records

Corporate records

Distributing read only material

Documents with assured accessibility (read to the blind)


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