Transcript Introduction to Animation

Working with Image Files
Aaron Fuegi
[email protected]
SCV Visualization Workshop – Fall 2008
Working with Image Files - Topics

Image Files
– Compression, Resolution, Formats, etc...
– Applications

Batch processing
– Working with image sets or sequences

Movies
– MPEG, DVD

Publications
– Resolution
– Color space
SCV Visualization Workshop – Fall 2008
Image Files
• PPM Image File – 24 bit color, 3 pixels by 3 pixels
P3
3 3
255
0
0
0
128 0
0
255 0
0
128 128 128 0
128 0
0
255 0
255 255 255 0
0
128 0
0
255
SCV Visualization Workshop – Fall 2008
Image Files - Issues

Compression
– None, Lossless, or Lossy
– Huge difference – 100 to 1 file size
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Image Size/Resolution
– Pixels vs. DPI (Dots per inch)
– Web or Printing


Web support – JPEG, PNG, GIF
Color Depth
– 24bit vs. 8bit – much less of an issue than it used to be
SCV Visualization Workshop – Fall 2008
Image Files - Formats
JPEG – Web, 24bit, Lossy, Small file size
 PNG – Web, 24bit
 GIF – Web, 8bit, Color lookup table
 TIFF, RGB, PPM – 24bit, Large file size, High
quality
 PSD – Photoshop’s format

– Editable text, Layers, etc…


RAW – Digital camera formats, multiple
MANY others
SCV Visualization Workshop – Fall 2008
Image Files - Applications


Viewing, Resizing, Manipulating Images
Adobe Photoshop
– Windows/Macintosh
– GUI, Very powerful, Expensive
– Most popular general image editing package

XV
– Mostly an image viewer but some editing capability
– GUI, Linux, Free, Easy to use, No longer being updated

ImageMagick
– Command-line tools
– Linux, Free
SCV Visualization Workshop – Fall 2008
Adobe Photoshop
SCV Visualization Workshop – Fall 2008
XV
SCV Visualization Workshop – Fall 2008
ImageMagick

Add a blue border around image (expand?, replace?,
shrink?)
– convert -border 10x10 -bordercolor "#6699ff" fan.png fan2.png

Add a caption/attribution
– convert -font helvetica -fill red -pointsize 14 -draw 'text
446,404 "[email protected]"' fan2.png fan3.png
SCV Visualization Workshop – Fall 2008
ImageMagick - Tools

Convert
– Convert image formats.
– Many image transformations available – scale, rotate,
text, artistic filters


Display
Import
– Screen capture under Linux

Identify
– Find out characteristics of image

Composite
– Composite multiple images together
SCV Visualization Workshop – Fall 2008
Batch Processing

Working with a set or sequence of images
– All images generally must be the same size

Adobe Photoshop
– Recording and applying actions

Perl (or another computer language)
– Extremely flexible but requires programming
background or help
– Augments command-line tools such as ImageMagick
SCV Visualization Workshop – Fall 2008
Movies

ImageMagick (Animated GIFs only)
– convert -delay 20 –loop 0 file*.gif anim.gif
– animate anim.gif

Adobe Premiere
– Movies
– Displaying on computer or DVD?
– Formats – QuickTime or AVI

Adobe Encore
– DVDs
– Menus, Controls, Chapters, etc…
SCV Visualization Workshop – Fall 2008
Images in Publications

Resolution
– Web – generally around 100 DPI
– Print – generally 600 DPI – match journal specifications
• Re-render image at very large scale. Do not just scale up.

File Format
– Use a lossless 24-bit color format such as TIFF or PNG

Color Space
– Web – RGB (standard)
– Print – CMYK

Printing
– Color gamut – Additive vs. subtractive color
SCV Visualization Workshop – Fall 2008
Working with Image Files - Questions?
Aaron Fuegi
[email protected]
SCV Visualization Workshop – Fall 2008