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Video on the Web. John H. Krantz Hanover College. Outline. What is Video Acquiring with a Digital Camera Creating with ImageJ Editing with QuickTime Delivering in a Webpage. General Video Issues. Image size Keep it small 320 x 240 is not uncommon Image color depth
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Video on the Web John H. Krantz Hanover College
Outline • What is Video • Acquiring with a Digital Camera • Creating with ImageJ • Editing with QuickTime • Delivering in a Webpage
General Video Issues • Image size • Keep it small • 320 x 240 is not uncommon • Image color depth • Normally full color • Video Length • The shorter the better • This file is ~ 5.5 meg in QuickTime and it is 17 seconds
General Video Issues • Frame rate: recall difference between apparent motion and flicker • 10 to 15 is really fine for most cases • And best you can expect on web
Acquiring with a Digital Camera • Find format of your video camera • mine is QuickTime • Can use digital zoom • original camera images are much larger than movie images so will be shrunk down • And digital zoom is before movie image
Acquiring with a Digital Camera • Hold camera still or not? • Movies are limited in duration • mine is 30 sec or size of disk for 320x240 • It is 120 sec if 160x120 • Image quality is reasonably good if presented in original size • But image quality may be reduced to get on web
Creating Animations with ImageJ • Stacks • Sequence of images to be played • Found under Image menu • Open the desired sequence in order • Image: Stacks: Convert Images to Stack • Can add and remove images (a Slice) under the same menu
Create Animations with ImageJ • Stack Menu • Can control frame rate under: • Image: Stacks: Animation Options • Get AVI writer plugin to save as a movie
Create Animations with ImageJ • Useful for making a slideshow • A frame rate of 1 frame per second is good • And as slow as can have in ImageJ
Slideshows • Can also do slideshows in web pages • In FrontPage it is built in • Insert: Web Component • Dynamic Effects: Banner Ad Manager • Limited in number of images to 9 • Here is an example
Slideshows • Or the following Java Script • Not limited in number • These do not stop but can go slower
Editing with QuickTime Pro • Open more than one • Basics • Opens MOV, mpg, avi, mp3, etc. • Get Movie Information on Movie Menu (ctrl-j in Windows) • Tracks: separate slices of information: played at same time as other tracks • Look under the Edit menu
QuickTime Pro Interface Playback head In marker Out marker Selected region
Basic Editing • Selecting a region to edit • Use guides at bottom • Called In and Out Markers • Selected region is darkened • Arrow keys to fine tune • Cut and Paste operation • Paste is at playback head
Adding Tracks • Copy as before • Use Edit: Add – adds the video track • Use Edit: Extract Tracks • Then Edit: Add • Can extract sound this way to a movie • Can add scaled so new track is not length of old movie
Deleting Tracks • Use Edit: Delete Tracks • Remove any unwanted sound from video
More Advanced Editing with QuickTime Pro • Adding text to beginning • Make any graphic • Resize to movie size so know how it will look • Select al (ctrl-A) • Then cut and paste to beginning • Another paste for each additional frame
More Advanced Editing with QuickTime Pro • Overlaying Text • Use a gif file with a transparent background • Use a text file • File: Import • Any .txt • Press Option button • Select keyed text • Change background to white and foreground to text color • I like changing it to bold • Add tracks as before
More Advanced Editing with QuickTime Pro • Filtering portions of movie • Delete regions do not want to filter • Use the export function • Click on Options • Click on Filter • Pick pattern • Use cut and paste to reassemble
Saving for Web • Format: • You must compress • Uncompressed files will be very large • Lead very slow download • Duration • For same reason, keep videos short
Steaming Starts sooner Can be large files Can stop Generally low quality General Protocol RTP/RTSP Regular Delivery Wait for entire file Keep to small files Keeps Speed Better quality To Stream or Not to Stream
Streaming vs. HTTP Fast Start • HTTP Fast Start is a feature of QuickTime • Allows playing after part of file downloaded • Fewer stops • No special software • Still keep files relatively small • Some loss of image quality
Embedding a QuickTime Movie in a Web Page <p align="center"> <OBJECT CLASSID="clsid:02BF25D5-8C17-4B23-BC80-D3488ABDDC6B" WIDTH="480" HEIGHT="376" CODEBASE="http://www.apple.com/qtactivex/qtplugin.cab"> <PARAM NAME="src" VALUE="start.mov"> <PARAM NAME="controller" VALUE="false"> <PARAM NAME="target" VALUE="myself"> <PARAM NAME="href" VALUE="http://psych.hanover.edu/Krantz/test/Invert2.mov"> <EMBED WIDTH="480" HEIGHT="376" CONTROLLER="false" TARGET="myself" HREF="Invert2.mov" SRC="start.mov" BGCOLOR="FFFFFF" BORDER="0" PLUGINSPAGE="http://www.apple.com/quicktime/download/indext.html"></EMBED></OBJECT> </p>