A Introduction to Scanning - University of Waterloo · 2012-02-01 · Scanning software will allow...

A Introduction to Scanning

Lowell Williamson AHS Computing March 18, 2005

An Introduction to Scanning 2 AHS Computing

Overview

Types of images

Scanning Pictures

Manipulating Pictures

Scanning Text

Location of files


HP Director Software

The HP Director Software allows the user to ‘direct’ themselves to the application that is appropriate for them


How to start a scan?

Most scanners have buttons on the front that will invoke an associated application

The standard buttons include

– Scan a picture

– Scan a document

– Make a copy

– Scan to email

Startup the application from the menus


What are you scanning?

It makes a difference what kind of scan you are performing

Different levels of resolution are required for different types of scanning


Preview the scan

Scanning software will allow you to preview your scan before saving it to a file

It is at this point you will have an opportunity to adjust resolution, output type, rotation, size etc. before saving the file


Types of Images

Bitmap

– The standard bit-mapped graphics format used in the Windows environment. By convention, graphics files in the BMP format end with a.BMP extension.

Jpeg

– file extension for JPEG (Joint Photographic Experts Group). A file stored in JPEG format. JPEG,an ISO/ITU standard for storing images with high compression capability, uses a discreet cosine transform that can achieve compression rates of 100:1 (significant loss of data from original) and 20:1 (minimal loss).

http://www.webopedia.com/TERM/B/standard.html

http://www.webopedia.com/TERM/B/bit_mapped_graphics.html



http://www.webopedia.com/TERM/B/format.html

http://www.webopedia.com/TERM/B/Windows.html

http://www.webopedia.com/TERM/B/environment.html

http://www.webopedia.com/TERM/B/graphics.html

http://www.webopedia.com/TERM/B/file.html

http://www.webopedia.com/TERM/B/extension.html


Types of Images

Tiff – Acronym for tagged image file format, one of the most

widely supported file formats for storing bit-mapped images on personal computers (both PCs and Macintosh computers). TIFF graphics can be any resolution, and they can be black and white, gray-scaled, or color. Files in TIFF format often end with a .tif extension.

Gif – Pronounced jiff or giff (hard g) stands for graphics interchange format, a bit-mapped graphics file format used by the World Wide Web, CompuServe and many BBSs. GIF supports color and various resolutions. It also includes data compression, but because it is limited to 256 colors, it is more effective for scanned images such as illustrations rather than color photos.

http://www.webopedia.com/

http://www.webopedia.com/TERM/T/support.html

http://www.webopedia.com/TERM/T/file_format.html

http://www.webopedia.com/TERM/T/store.html

http://www.webopedia.com/TERM/T/bit_map.html



http://www.webopedia.com/TERM/T/personal_computer.html

http://www.webopedia.com/TERM/T/PC.html

http://www.webopedia.com/TERM/T/Macintosh_computer.html

http://www.webopedia.com/TERM/T/Macintosh_computer.html

http://www.webopedia.com/TERM/T/graphics.html

http://www.webopedia.com/TERM/T/resolution.html

http://www.webopedia.com/TERM/T/gray_scaling.html



http://www.webopedia.com/TERM/G/bit_mapped_graphics.html



http://www.webopedia.com/TERM/G/file_format.html

http://www.webopedia.com/TERM/G/World_Wide_Web.html

http://www.webopedia.com/TERM/G/CompuServe.html

http://www.webopedia.com/TERM/G/bulletin_board_system_BBS.html

http://www.webopedia.com/TERM/G/support.html

http://www.webopedia.com/TERM/G/resolution.html

http://www.webopedia.com/TERM/G/data_compression.html

http://www.webopedia.com/


DPI = Resolution

The term dpi means Dots Per Inch, referring to image "pixels per inch" (but printer dpi is different than image dpi).

The meaning of scanned dpi is that if you scan a 6x4 inch photo at 110 dpi, then you will necessarily get an image size of :

(6 inches x 110 dpi) x (4 inches x 110 dpi) = 660 x 440 pixels

– which more or less totally fills a 640x480 monitor screen.

Or scanning the 6x4 inch photo at 140 dpi gives (6 inches x 140 dpi) x (4 inches x 140 dpi) = 840 x

560 pixels – which more or less totally fills a 800x600 monitor screen.

Or scanning the 6x4 inch photo at 180 dpi gives (6 inches x 180 dpi) x (4 inches x 180 dpi) = 1080 x

720 pixels – which more or less totally fills a 1024x768 monitor screen.


Resolution

Guideline for resolution?

75 – 150 dpi for the web

200 – 600 dpi for printing

600 dpi + for digital photography


Comparison???

Can you tell the difference? Is there a difference???


Resizing

Because bitmaps are resolution dependent, it's difficult to increase or decrease their size without sacrificing a degree of image quality. When you reduce the size of a bitmap image through your software's resample or resize command, you must throw away pixels.

When you increase the size of a bitmap image through your software's resample or resize command, the software has to create new pixels. When creating pixels, the software must estimate the color values of the new pixels based on the surrounding pixels. This process is called interpolation.

http://graphicssoft.about.com/library/glossary/bldefresample.htm

http://graphicssoft.about.com/library/glossary/bldefinterpolation.htm


Resizing

When resizing a picture make sure to keep the aspect ratio

For instance if you were to only reduce the height of a picture, then everything would appear ‘squished’


Manipulating a Photo

Scanning software will allow the user to rotate, crop, lighten/darken a photograph

If a photograph is damaged, it can be restored to its original condition

This step can be completed prior to saving the file or it can be done in post production


Post-Production

Select View & Print in the HP’s Director software

Demonstration


Post Production


Scanning a document

Depending on the scanner and the software the choice to scan to:

– Wordpad (OCR)

– PDF

– Image


OCR

Often abbreviated OCR, optical character recognition refers to the branch of computer science that involves reading text from paper and translating the images into a form that the computer can manipulate (for example, into ASCII codes).

An OCR system enables you to take a book or a magazine article, feed it directly into an electronic computer file, and then edit the file using a word processor.

http://www.webopedia.com/TERM/o/optical_character_recognition.html

http://www.webopedia.com/TERM/o/computer_science.html



http://www.webopedia.com/TERM/o/text.html

http://www.webopedia.com/TERM/o/ASCII.html

http://www.webopedia.com/TERM/o/computer.html

http://www.webopedia.com/TERM/o/ASCII.html

http://www.webopedia.com/TERM/o/system.html

http://www.webopedia.com/TERM/o/file.html

http://www.webopedia.com/TERM/o/file.html

http://graphicssoft.about.com/library/glossary/bldefresample.htm

http://www.webopedia.com/TERM/o/optical_character_recognition.html


Pitfalls of OCR

You will still have to edit the document for characters that were not recognized

– This could be tedious and time consuming

Formatting will still need to be need to done


Use My Pictures

My Pictures is located in My Documents

This is an excellent place to store pictures

– By default most applications will try to store picture file types to this directory

Use thumbnails to obtain a preview of the files without having to open the file

Protect your scanner

Try to avoid moving your scanner

Do not touch the scanning surface

To clean the surface, use a mixture of

– ½ water

– ½ alcohol


Other tips

Be patient… if a scan does not appear right away do not become click happy

If at first you don’t succeed…

Give your scans names that are applicable/relevant and organize them in folders

Save a copy of the scan before you edit the original



Question & Suggestions…

If you have questions or suggestion, please contact me at your leisure

Lowell Williamson

[email protected]

mailto:[email protected]

A Introduction to Scanning - University of Waterloo · 2012-02-01 · Scanning software will allow...

Documents

Transcript of A Introduction to Scanning - University of Waterloo · 2012-02-01 · Scanning software will allow...