LRC Mini-Workshop: Downloading and Editing Videos from YouTube

I. Intro A. Video is certainly a compelling teaching tool for classroom/Web use (1.) Fast internet/computer speeds, easy-to-use video websites and inexpensive recording devices create access to lots of content (2.) Students are used to getting content from Web video sources (3.) Programs and technologies are constantly changing (4.) Websites and applications that work for you today may not be supported in the future or work with a different computer (5.) Even if you have the content you require, the Video File Size may be too large, the Data Rate may be too high or it might be the wrong File Type to make it useful online

II. Glossary of Media File Terms A. File Type/Format/Extension (1.) QuickTime (.MOV): Apple video/audio format that plays on Mac and Windows in free QuickTime Player or browser plug-in (2.) Windows Media Video (.WMV): Microsoft video format that plays in Windows Media Player (3.) Flash (.FLV): a multimedia format that plays in Adobe Flash Player because of its or browser plug-in; the choice of many websites that contain video because of its small file size and data rate (4.) MPEG-4 (.MP4): flexible format used for both streaming and downloadable Web content; can play in most media players and is used by a growing number of solid state camcorders (5.) M4V: format for videos for iTunes, iPods and PlayStation Portables (6.) Audio-Video Interleaved (.AVI): A non-compressed file format for storing and playing videos/audio on Windows-based PCs. (7.) MPEG-3 (.MP3): most popular format for storing and transferring music; about a tenth the size of uncompressed audio files. (8.) Advanced Audio Codec (.AAC): Apple audio format that uses a more advanced form of compression that delivers higher quality at lower data rates and file sizes; used in iTunes Store, Sony PlayStation3; may also appear with the (.M4A) or (.MP4) file extension; Songs with DRM (digital rights management) from the iTunes Store usually have an (.M4P) extension (9.) Media file formats often need to be converted (transcoded) to a different file type in order to work in a different program, server or application

B. Codecs (1.) Definition: a device or computer program capable of encoding and/or decoding a digital data stream or signal. The word codec is a portmanteau (a blending of two or more words) of 'compressor-decompressor' or, 'coder-decoder'. (2.) Some Common Codecs: Sorrenson 3, Sorrenson Spark, Real Video, Cinepak, DivX, FFmpeg, Indeo, Xvid, H.264 (3.) H.264: a compression codec that yields very high quality MPEG-4/AVC video at low data rates and file sizes; popular for its use in Blu-ray Discs and videos in Apple’s iTunes Store; the preferred version of MPEG-4 video at Cornell LRC C. Data Rate or Bit Rate (1.) Definition: the number of bits used per unit of playback time in video after compression; the size of a multimedia file in bytes is the product of the bit rate measured in bits per second (bit/s) and the length of the recording (in seconds), divided by eight. (2.) High Data Rates (Bit Rates) usually yield high quality video with large file sizes; fast Internet connections, wireless networks and computers are needed for smooth playback (3.) Low Data Rates (Bit Rates) usually yield fuzzy/blotchy video with small file sizes; slow Internet connections, wireless networks and computers will still usually play these files (4.) Target Data or Bit Rate that yields a balance of good quality video at manageable rates that should play properly on most computers is between 350 and 650 kbits/second. (5.) Where to see the Data or Bit Rate in a video file in QT (a.) Mac: Window>Show Movie Inspector or Right-Click>Get Info (b.) Windows: Window>Show Movie Inspector (6.) YouTube videos and most of the video found on the Web are already compressed and usually do not need to be further compressed in the way that video from a camcorder will

D. Screen Size/Resolution (1.) Definition: the dimensions of a video expressed in width (x) height, measured in pixels. (2.) Some common screen sized/resolutions: (a.) Web Video = 320x240 (b.) Standard Definition TV in the US = 640x480 or 720x480 (c.) Standard Definition TV in Europe = 768x576 (d.) Standard Definition LCD computer screen = 1024x768 (e.) High Definition 720p TV in the US = 1280x720 (f.) High Definition 1080i in the US = 1920x1080 III. Download and Convert YouTube Videos A. Tech Sheets at LRC website: http://lrc.cornell.edu/lrc_info/tech/DownloadingAndHandlingVideo (1.) KickYouTube – 1-Sheet and Demo (2.) Zamzar – Demo at: http://www.zamzar.com/url/

IV. Editing YouTube videos in QuickTime Pro 7 A. QuckTime Pro 7 site at: http://www.apple.com/quicktime/pro/ B. lrc.cornell.edu>Center Info> Teacher Resources>Technical DocumentationEditing in QT Pro Tech Sheet (1.) Save a portion of your video (2.) Delete a portion of your video