Guidelines for Media Files (Audio, Video, PDF)

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Adobe PDF files

PDF (Portable Document Format) is the worldwide standard for document exchange. A PDF file preserves the text, page size, layout, fonts and graphics from any file created in any application. The same is not true for Microsoft Word files, which require fonts installed on the user's local computer; also, page size, default fonts and other aspects of page layout may differ if readers have changed default template settings in their own installation of Word. For these reasons, PDF is the preferred file format for posting syllabi, lectures, readings and other course materials.
A PDF file contains a description of page dimensions as well as fonts and images to render each page of a documents. PDFs are "device independent," and, essentially, every device used to view or print a PDF is treated as a printer. Viewing a PDF is printing it to your screen; printing a PDF is translating the document layout and content for the specific printer connected to your computer. It is this device-independence that led to the world-wide acceptance of PDF as a standard.

Adobe Reader

Adobe Corp. provides the reading software that enables opening, reading, and printing PDFs. This free software works on all platforms. Adobe Reader (now called Adobe Acrobat DC) must be installed in order to read PDFs.
[Get Adobe Acrobat Reader | http://www.adobe.com/products/reader.html]

Viewing PDFs in a browser

Some browsers, such as Firefox, have a plug-in that permits reading PDFs inside the browser. In the absence of a browser plugin, users must first download a PDF to their computer from a Sakai site or web page, and then open it in Adobe Reader.
[Firefox PDF viewer information | http://support.mozilla.org/en-US/kb/view-pdf-files-firefox-without-downloading-them?redirectlocale=en-US&redirectslug=Opening+PDF+files+within+Firefox]
The browser plug-in typically has both a "download" and a "print" option so that the user can download a copy of the PDF, or send it to a local printer. Once a file is downloaded to the user's desktop or local folder, the Adobe Reader can be used to open, view and print this file. Additional PDF features such as highlighting and book marking can only be done on the downloaded copy of a PDF.
Adobe Corp. has provided the following tips for those having difficulty opening a PDF online:
[Acrobat Help/ Can't view PDf on the web | http://helpx.adobe.com/acrobat/kb/cant-view-pdf-web.html]
Here are instructions from Firefox on how to switch off their built-in PDF viewer so that you can choose Adobe Acrobat Reader as the preferred PDf reader:
[Switching off Firefox's PDF Viewer | https://support.mozilla.org/en-US/kb/disable-built-pdf-viewer-and-use-another-viewer]

Browser opens PDF but shows only a blank (black) screen

Recently, we have heard from students saying they have opened a PDF with the Firefox PDF viewer in Sakai but they see only a black area, with no pages visible. This seems to be happening with PDFs which are made from scans, rather than PDFs made in applications such as Word. What appears to be happening is that a large empty area is made UNDER the actual pages. Look for the scrollbar on the right, and scroll up to the top, where the pages are visible.

Problems viewing or navigating a PDF in Chrome

Users of the Chrome browser may have some problems viewing and navigating through embedded PDFs in Sakai, such as those set to display on the Sakai Syllabus or Sakai Lessons. Chrome's built-in PDF viewer appears to be at fault, but a PDF reader plug-in can be added to Chrome which reportedly behaves better. More information here:

[About Chrome PDF Plugins | http://www.iceni.com/blog/problems-opening-and-browsing-pdfs-in-google-chrome/]

Making PDFs from user applications

Many word processing and office applications, either natively or with a plug-in, can make PDF files. Most typically, Adobe Acrobat appears on the application's PRINT menu. Quite literally, Adobe Acrobat PDF is an imaginary printer on the user's list of printers. This feature is now so widespread that "printing to PDF" is a common activity.

Advanced PDF editing

The full Adobe Acrobat Professional Suite is required to perform advanced editing features in PDF documents. With the full Professional Suite you can:
  • delete pages from a PDF
  • insert pages from another PDF
  • convert a group of image files and Word files into a single PDF
  • create fill-in forms inside a PDF
  • combine multiple PDFs into a single "portfolio" file
  • crop pages in a PDF to conceal unwanted content
  • permanently change orientation of a page or a range of pages
  • edit an image inside a PDF without having access to the original image file
[Adobe Acrobat Pro Features | http://www.adobe.com/products/acrobatpro/features.html]

Scanning documents to PDF

Recommended scanner for scanning books, articles and manuscripts

Although most document scanners suffice for small scanning jobs, scanning bound books and documents with mixed content (black, grayscale and color content) is cumbersome on a normal flatbed scanner. High-end book scanners used by libraries can cost up to $15,000, but there is one attractive alternative costing under $300: the Plustek Opticbook scanner. Several URI departments have installed this scanner, along with OCR software. This scanner eliminates black stripes when a book is scanned with two facing pages on the scanner glass. It also has a unique design in which the scanner glass is only 1/4-inch from the edge of the scanner, allowing a book to be hung from the edge of the scanner for page-at-a-time scanning. We have not seen any other low-cost scanner that is this versatile and productive.
[Info on Plustek Scanner | http://plustek.com/usa/products/opticbook-series/opticbook-3800/]

Making text-searchable, accessible PDFs

A PDF for use in Sakai should be well-formed. Its text should be searchable and selectable for cut-and-paste. A PDF that is just a scan of a printed page does not contain any serchable text: it is just dots. In order for a scan-based-PDF to become searchable and accessible, it must have an invisible text layer created by performing Optical Character Recognition (OCR) on the scan. And in order to be readable for OCR, the scans must be at least 300 dpi.
The accessibility issue is important. A PDF with a text layer can be read aloud to visually-impaired students directly in the Acrobat Reader. If the PDF is missing this, the student must print out the PDF, pass it through the JAWS reader, and only then have it read aloud. It is obviously preferable to have all PDF files accessible from the start.


At the present time, there are two ways to add text layers to PDFs:
  • Install the full Adobe Acrobat Professional Suite and use its OCR feature to detect text and add a text layer to the PDF.
  • Use a commercial OCR program like ReadIRIS or Abby Fine Reader to process the scanned files, making a new PDF with a text layer in it.
While the OCR feature in Adobe Acrobat Professional Suite will produced acceptable results most of the time, ReadIRIS adds additional support for foreign languages, and successfuly identifies tables and graphic elements. READIris also permits export to other formats including Word files, XML, HTML web pages and wiki pages. Used in combination with the Plustek book scanner, we have found READIris to be a highly effective program for preparing content for Sakai.
[Information about READIris | http://www.irislink.com/c2-2513-189/Readiris-14---OCR-Software---Scan--convert---manage-documents.aspx]

Guidelines for document scanning

  • Use your scanner's "preview" option to exclude areas beyond the margins. When students attempt to print out PDFs with huge black areas around the pages, someone has to pay for all that ink or toner. It is a courtesy to the reader to make a clean, neat scan.
  • Use black-and-white scan settings, 300 dpi, for text-only pages. Make sure you do not use anything lower than 300 dpi, such as "fax quality."
  • Use gray-scale settings, 300 dpi for all pages that contain tinted areas, headlines in pale colors, or black-and-white photos. You can also use grayscale settings to scan color pages if you determine that nothing will be lost by scanning only in grayscale.
  • Use color settings, 300 dpi, for pages containing color content. Art reproductions, color-coded maps and charts and some other content require full color scanning.
  • Scan original articles and books whenever possible, instead of scanning Xerox copies that have already lost quality and legibility.
  • Process your scans via an OCR program, or via Adobe Acrobat Pro's "recognize text" option, so that your PDFs have text-searchable content.
  • Do not use an office copier's "scan to PDF" feature unless the copier is capable of delivering the quality level and black-area cropping described above.

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Ebooks (epub format)

Many texts are available as ebooks. Epub is the most common format, and epub files can be read with a browser extension, or with a freestanding reader such as Calibre. Students can also convert epub files so that they can be read on a Kindle reader (see Calibre software below).
Epub files differ from PDFs in that the text flows continously, and the user can choose fonts and font size for reading comfort.
It is also possible to make your own epub files to make student readings more reader-friendly. There are various pros and cons about PDFs versus epub files, but the key difference is that PDFs are paginated, with layout and page size dictated by the document creator, whereas epub files are fluid and not paginated.

Making your own epub files

The open source program Sigil can be used to make epub files from scratch. It is an HTML editor with all the formatting required to make properly-formatted epub files. It takes a while to learn the ins and outs of this program but it is powerful and produces an ebook file up to publisher standards. Sigil can be obtained from:
[Download Sigil | https://code.google.com/p/sigil/]
Ebooks can also be converted among different formats using Calibre (see below).

Calibre, the Ebook reader and manager

Calibre is a free and open source e-book library management application developed by users of e-books for users of e-books. It has a cornucopia of features divided into the following main categories:
  • Library Management
  • E-book conversion
  • Syncing to e-book reader devices
  • Downloading news from the web and converting it into e-book form
  • Comprehensive e-book viewer
  • Content server for online access to your book collection
  • E-book editor for the major e-book formats
You can use Calibre to convert downloaded, unprotected epubs into other formats, such as Kindle.
Calibre runs on all platforms. You can download it from:
[Download Calibre | http://calibre-ebook.com/download]

Reading epubs in Firefox

It is possible to read epub files online with the Firefox browser, or by pointing the browser to a downloaded epub file. This is done with a Firefox plugin which can be obtained at:
[Get Firefox Epub Plugin | https://addons.mozilla.org/en-us/firefox/user/epubreader/]

Ebooks from University of Adelaide

The University of Adelaide in Australia has put up thousands of ebooks of literature, classics and history on their website, where they can be read or downloaded in epub and/or Kindle format. These are good examples of well-formatted ebooks.
[Ebooks at Adelaide | http://ebooks.adelaide.edu.au/]
For a good overview of various ebook formats, this Wikipedia page is recommended:
[Comparison of ebook file formats | http://en.wikipedia.org/wiki/Comparison_of_e-book_formats]

Accessibility issues

The epub format uses HTML tags that can be read by some text-to-speech applications, so long as the file does not contain restrictive Digital Rights Management (DRM). The latest epub format, called epub3, adopted in 2013, is now reaching adoption by publishers, and the new format will resolve some problems that hindered accessibility, such as dealing with math formulas, which were graphics-only in earlier versions.
Owners of the iPad can have ebooks read aloud via the iPad's built-in accessibility features. Here is a video showing how this is done.
[iPad settings to read an ebook aloud | http://www.youtube.com/watch?v=AgDdB4FhHrk]
The same feature is available on the Mac:
[Read ebooks aloud on a Mac | http://www.cultofmac.com/170577/have-your-mac-read-ebooks-to-you-os-x-tips/]
Here is an Android app for reading text aloud:
[Android app for reading text aloud | https://play.google.com/store/apps/details?id=com.noinnion.android.voicereading]
The Kindle DX and the Kindle Fire models have text-to-speech conversion built-in.
JAWS for Windows, VoiceOver and Safari on the Mac are capable of reading aloud unprotected epub files. Files which come from publishers who have restricted rights to their books via Digital Rights Management (DRM) usually prohibit conversion, printing, or text-to-speech conversion. If you make your own epub files with the programs notes above, you can elect not to have DRM.

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Image files

Editing image files

Image files are often too big for the intended use in Sakai:
  • Images scanned at high resolution (300 or even 600 dpi are not uncommon) will cause slow load and download time, and may in some cases display larger than intended -- whereas images need be no more than 72 dpi or 96 dpi for screen display.
  • Images may be too large in terms of their dimensions as well: a scan of an 8-inch wide photo may need to become a 5-inch wide photo for use in Sakai.
  • Images may also be unnecessarily large because they were scanned at the wrong setting: black-and-white content scanned in full color is a typical example.
  • Some images may serve instructional needs better if they are cropped, eliminating unwanted portions of the image and retaining only the important part.
  • Some acquired images may be in a file format that cannot be displayed online (such as TIF).
  • Placing many high-resolution images inside a Word file, PowerPoint or PDF can make the file so large that students will have difficulty downloading and printing it.
Instructors and students alike need to have access to photo-editing software that imports, edits and exports image files to various formats and sizes. Adobe Photoshop, part of the Adobe Creative Suite, is the world standard for image editing; two other commercial products are Corel Photo-Paint and Serif Photo Plus.
[Free Starter Edition of Serif Photo Plus (PC only) | http://www.serif.com/free-photo-editing-software/]
A free, open source alternative is GIMP, which runs on all platforms and includes most of the functionality of Photoshop. With GIMP, instructors and students can perform all the image editing tasks.
[Download page for GIMP | http://www.gimp.org/downloads/]
The GIMP community now has its own free online magazine that helps users learn how to do many tasks with GIMP.
[GIMP Magazine Home Page | http://gimpmagazine.org/ ]
A very versatile utility that lets you split two-page scans into separate image files, and crop white areas around text, is called Scan Tailor:
[Download Scan Tailor for PC | http://scantailor.sourceforge.net/\]
[Download Scan Tailor for Mac | https://code.google.com/p/scantailor-osx/]

Still image capture from screeen

There are a variety of utilities and programs that facilitate capturing a still image from your computer monitor. The simplest ones simply do a "Print Screen" function to an image file, which can then be edited and cropped in an image editing program such as GIMP or Photoshop. Others are more sophisticated, letting you select specific areas of the screen so that further editing will not be needed. Here are some examples:
ShareX for Windows. ShareX (Windows only). Make JPG or PNG image files from your screen, or from a portion of your screen. This can be used to create image files to use in Sakai Lessons. ShareX is an open-source program that lets you take screenshots, save them in your clipboard, hard disk or upload them to over 20 different remote locations. ShareX can capture screenshots with different shapes: rounded rectangle, ellipse, triangle, diamond, polygon and also free hand. It can also upload images, text files and all other different file types. It is able to capture screenshots with transparency and shadow. The program also supports drag and drop, clipboard upload and Windows Explorer integration.
[Get ShareX | http://getsharex.com/ ]
"Mac screenshots. There are built-in commands on a Mac for making screen shots. See these instructions:
[Making screen shots on a Mac | http://guides.macrumors.com/Taking_Screenshots_in_Mac_OS_X]

Image file formats

PNG
Portable Network Graphics is a raster graphics file format that supports lossless data compression. PNG was created as an improved, non-patented replacement for Graphics Interchange Format (GIF), and is the most used lossless image compression format on the Internet.
PNG supports palette-based images (with palettes of 24-bit RGB or 32-bit RGBA colors), grayscale images (with or without alpha channel), and full-color non-palette-based RGB images (with or without alpha channel). PNG was designed for transferring images on the Internet, not for professional-quality print graphics, and therefore does not support non-RGB color spaces such as CMYK.
PNG files nearly always use file extension PNG or png and are assigned MIME media type image/png. When uploading to Sakai, please be sure to use the ".png" file extension in lowercase. Some functions in Sakai will not work correctly on files with uppercase extensions.
Graphics editing programs such as Photoshop and GIMP are capable of saving to PNG files from GIF, JPG or TIF formats. --(Adapted from Wikipedia definitions).
JPG
JPEG(seen most often with the .jpg extension) is a commonly used method of lossy compression for digital images, particularly for those images produced by digital photography. The degree of compression can be adjusted, allowing a selectable tradeoff between storage size and image quality. JPEG typically achieves 10:1 compression with little perceptible loss in image quality.
JPEG compression is used in a number of image file formats. JPEG/Exif is the most common image format used by digital cameras and other photographic image capture devices; along with JPEG/JFIF, it is the most common format for storing and transmitting photographic images on the World Wide Web. These format variations are often not distinguished, and are simply called JPEG.
The term "JPEG" is an acronym for the Joint Photographic Experts Group, which created the standard. The MIME media type for JPEG is image/jpeg (defined in RFC 1341), except in Internet Explorer, which provides a MIME type of image/jpeg when uploading JPEG images.--(Adapted from Wikipedia definition).
JPEG files uploaded to Sakai should have the ".jpg" extension in lowercase letters. Uppercase extensions can cause some problems in some Sakai functions.
Although some student work may require that JPGs be posted or attached at higher resolutions (300 dpi being sufficient for quality printing), most JPGs included in syllabi, forum postings, Sakai Lessons, etc., need be only 72 dpi or 96 dpi for good screen display. Files at high dpi may display too large on monitors and may force the screen to scroll to the right, making the reading of text above and below difficult. For this reason, posters need to use a graphics editor like Photoshop or GIMP to make JPGs that are a suitable size and dpi resolution for the intended purpose. An optimum image size for Sakai might be something like 450 pixels wide at 96 dpi.
JP2 or JP2000
JPEG 2000 is an image compression standard and coding system. It was created by the Joint Photographic Experts Group committee in 2000 with the intention of superseding their original discrete cosine transform-based JPEG standard (created in 1992) with a newly designed, wavelet-based method. The standardized filename extension is .jp2 for ISO/IEC 15444-1 conforming files and .jpx for the extended part-2 specifications, published as ISO/IEC 15444-2. The registered MIME types are defined in RFC 3745 as "image/jp2."
JPEG 2000 code streams are regions of interest that offer several mechanisms to support spatial random access or region of interest access at varying degrees of granularity. This way it is possible to store different parts of the same picture using different quality.
JPEG 2000 has been published as an ISO standard, ISO/IEC 15444. As of 2013, JPEG 2000 is not widely supported in web browsers, and hence is not generally used on the Internet. (Adapted from Wikipedia.)
For the reason stated above, do not use jp2 files in Sakai unless you are attaching or exchanging files (Messages or DropBox or Assignments) that students will open and edit in an application that supports the JP2 format, such as later versions of Photoshop.
JP2 files are also encountered when downloading original raw scans from archive.org. Many book scans use the jp2 format for storing the original scans of book pages. So, although you might go to archive.org in order to download the jp2 files for illustrations in a book, those jp2 files cannot be uploaded to Sakai if the intent is to have the students view them in the browser. (BR)
TIF
The Tagged Information File Format (TIFF or TIF) is used primarily in the printing and publishing industries. The color information contained in a TIF file corresponds to the four standard ink colors used in process color printing (red, yellow, cyan blue, and black). TIF files must be converted into red-green-blue data for display on a computer monitor, so that these files can usually only be opened in an image editing program like GIMP or Photoshop.
Since most browsers will NOT display TIF files, the TIF format is not used in Sakai. Please use GIMP or Photoshop to convert TIF files into PNG or JPG before using them in Sakai.
If your scanner is producing TIF files by default, check the settings in your scanner software and change the default to JPG or PNG.
GIF
GIF files are typically used for small graphics such as logos and art and design elements on a web page. Because GIF files can have transparent backgrounds, they are very adaptable for web designed. "Animated GIFs" contain multiple image files that display in succession like an animated cartoon. For most other purposes, GIFs have been supplanted by JPG and PNG files. JPG, PNG or TIF files can be exported to GIF in GIMP, Photoshop or other photo editing software. For overall quality, PNG and JPG files are preferred in Sakai.

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Audio files

Playing audio files

In Sakai, the Apple Quicktime player is the default player for audio MP3 files. When an MP3 is added to Sakai Lessons, the Quicktime player will appear on the screen. Sakai users must install Apple Quicktime on their computers.
If an audio file is attached to a Message, Forum, Discussion posting, Podcast, Assignment or Quiz, on the other hand, the file is indicated by a link. When the student clicks on the link, the file will download to the student's computer, and whatever media player the student has installed will play the audio MP3 file.

File formats

There are two kinds of compressed audio formats, "lossy" and "lossless." Lossy compression schemes drop out data from a sound file that the human ear cannot distinguish -- and once removed, those data cannot be restored. A lossless file format compresses data, but the process can be reversed, restoring the original, high-quality data. Playback of lossless files is indistinguishable from the original recording. The predominant lossy format, MP3, is used for most audio downloads and is the most common format found in Sakai. When a student clicks on a link to an MP3 file, Apple Quicktime opens and plays the MP3. If an MP3 or other audio file is downloaded by the user, the user's preferred media player will open and play the audio file.
MP3
MP3 is a compressed audio format that permits sound files to be virtually indistinguishable from original WAV files, with a file size as small as 10% of the original. MP3 is the standard fil format for music downloads, for portable media players, and for audio books and audio podcasts. MP3 comes in various "flavors," with varying degrees of fidelity to the original. VBR (variable bit rate) MP3 recordings devote the amount of compression that each part of a recording requires, whereas CBR (constant bitrate) applies the same compression to every part of a recording, whether there is silence or an entire orchestra playing fortissimo. Speech content such as podcasts can usually be delivered with a 128kbps bitrate. Music content requires higher bitrates and hence larger files.
Many media player programs are capable of "ripping" a track from an audio CD into MP3 format, and many digitial audio recorders, although they record WAV files, are able to export MP3s.
WAV
WAV files are the original uncompressed audio files used in audio recording, and as found on an audio CD. WAV files are too large to be used in Sakai. Always convert WAV files to MP3.
FLAC
FLAC - (Free Lossless Audio Codec) is a codec for lossless compression of digital audio. Digital audio compressed by FLAC's algorithm can typically be reduced to 50–60% of its original size and decompressed to an identical copy of the original audio data. Since FLAC files can be played in VLC Media Player and most other media players, they can be uploaded to Sakai Resources or Lessons. Students must have a FLAC-capable media player installed. The more-common MP3 format is preferred for Sakai.
WMA
WMA (Windows Media Audio) is a lossy, compressed audio file format developed by Microsoft to address some quality issues around MP3s. It is still an open question whether WMA files sound better than MP3 files at the same compression rate, but this issue has become moot because of the arrival of lossless compression formats like FLAC, OGG and APE.

Recording audio files

Audacity audio recorder

Using the free sound recorder, Audacity, you can record your voice from your computer microphone or headset (headset preferred), into a WAV file and export it to a compressed MP3 file that can be placed in Resources, Lessons, or the Sakai Podcast tool. Audacity's very small user interface looks like a simple tape recorder. Files made with Audacity can be edited (cut, copy-and-paste inside the WAV file), and additional sound layers can be added. For example, actors could read a script on one track, and sound effects can be added on another.
[Download Audacity for PC or Mac | http://audacity.sourceforge.net/download/]

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Video files

Playing video files

File formats

MP4
MP4 is the preferred video format for use in Sakai. (The webm format is probably better, and will supercede MP4 once all browsers and media players resolve on methods of embedding and playing webm). MP4 is capable of suppoprting audio, video, and subtitles.
[Details on MP4 format | http://en.wikipedia.org/wiki/MP4]
Most other video file formats can be converted to MP4. The open source PC application ATube Catcher, for example, can convert almost any video file into MP4.
Video conversion applications let the user select a frame size for the MP4 video to be out, ranging from high definition all the way down through a 320pc wide video that can be displayed with ease on portable devices. Users need to choose a display size suitable to the material. A "talking head" video does not need to be large, while a screen shot demonstrating software needs to be 640 px wide for clear viewing on the user's monitor.
AVI
Audio Video Interleaved (also Audio Video Interleave), known by its initials AVI, is a multimedia container format introduced by Microsoft in November 1992 as part of its Video for Windows technology. AVI files can contain both audio and video data in a file container that allows synchronous audio-with-video playback. Like the DVD video format, AVI files support multiple streaming audio and video, although these features are seldom used. Most AVI files also use the file format extensions developed by the Matrox OpenDML group in February 1996. These files are supported by Microsoft, and are unofficially called "AVI 2.0". (from Wikipedia).
Since AVI files can be played by most media player software, AVI files can be uploaded to Sakai Resources or Sakai Lessons. Most students will have to download AVI files before playing them.
When making video files from other formats, mp4 or webm formats are preferred.
MOV
Video, audio and text file format developed by Apple. MOV videos are almost indistinguishable from MP4 videos. Since Quicktime files are easy to edit, and since many users have been using the Apple Quicktime player for years, the MOV format remains popular. Some Sakai tools such as Lesson can display and play MOV files right on the screen without requiring a download. The MOV format has largely been supplanted by MP4, AVI and other formats.
MKV
The Matroska Multimedia Container is an open standard free container format, a file format that can hold an unlimited number of video, audio, picture, or subtitle tracks in one file.[1] It is intended to serve as a universal format for storing common multimedia content, like movies or TV shows. Matroska is similar in concept to other containers like AVI, MP4, or Advanced Systems Format (ASF), but is entirely open in specification, with implementations consisting mostly of open source software. Matroska file extensions are .MKV for video (with subtitles and audio), .MK3D for stereoscopic video, .MKA for audio-only files, and .MKS for subtitles only.
The webm audio/video format is based on Matroska. Windows 10 will support playing of mkv files natively.
WEBM
WebM is a digital multimedia container file format promoted by the open-source WebM Project. It comprises a subset of the Matroska multimedia container format. WebM files consist of video streams compressed with the VP8 video codec and audio streams compressed with the Vorbis audio codec. Since some of the earlier file formats were "containers" that accommodated several different video file types, and, as a result, did not play consistently across browsers, the developers of the webm format chose only a single video format and a single audio format. The result is, that is a browser plugin or media player says it plays webm, it will play all webm files.
This format, adopted within HTML5, is expected to be the dominant video file format in the years ahead. Webm files are capable of streaming from a regular web page (http), and can be either video or audio-only.
YouTube is supporting webm in addition to its existing formats as part of its HTML5 experiment. If you have installed ATube Catcher or another YouTube file catcher, you should be able to download many recent YouTube videos in the webm format.
Webm files can be played with subtitles, with a media player that enables subtitles. Subtitles are contained in a text file with the .srt format.
Webm files can be embedded in Sakai Lessons. Most browsers will play these files right on the Lessons page. Others may need to install the VLC Media Player plugin (Firefox) or download the VLC Media Player program, available for all platforms.
FLV and SWF (Flash)
Flash Video is a container file format used to deliver video over the Internet using Adobe Flash Player version 6 and newer. Flash Video content may also be embedded within SWF files. There are two different video file formats known as Flash Video: FLV and F4V. The audio and video data within FLV files are encoded in the same manner as they are within SWF files. Both formats are supported in Adobe Flash Player and developed by Adobe Systems. FLV was originally developed by Macromedia, so you will occasionally see these files referred to as "Macromedia Flash."
Flash Video is the de facto standard for web-based streaming video (over RTMP). Notable users of it include YouTube, Hulu, VEVO, Yahoo! Video, metacafe, Reuters.com, and many other news providers. Many providers of media content have tried, with varying degrees of success, to move away from Flash, because Apple iOS devices do not support the Flash Player Plugin.
Flash Video is viewable on most operating systems via the Adobe Flash Player and web browser plugin or one of several third-party programs. Apple's iOS devices do not support the Flash Player plugin and so require other delivery methods such as provided by the Adobe Flash Media Server.
If you have FLV files and you have decided to use them in Sakai, you must save those files as SWF. Sakai will play SWF files, but not FLV. Applications that let you save FLV files should have a "save as" setting to permit SWF export.

Free media players to download

[Get VLC Player | http://www.videolan.org/]
Also check your browser for availabiltiy of a VLC browser plugin.
[Get Apple Quicktime Player | http://www.apple.com/quicktime/download/]
[Get RealPlayer Cloud player | http://www.real.com/]
[Get Adobe Flash Player | http://get.adobe.com/flashplayer/]

Capture and download YouTube videos

For Windows users, the program ATube Catcher is a versatile tool for downloading YouTube videos, including the ability to download videos and convert them among many different formats.

[Get ATube Catcher (Windows only) | http://atube-catcher.dsnetwb.com/video/]
A number of Firefox add-ons have been developed to download YouTube video files. Go to the Add Ons Manager in Firefox and enter "YouTube download" in the Search box to see a number of choices. ATube Catcher is the best choice for Windows users, but Mac and Linux users can avail themselves of these other options.
Why would you want to download a YouTube video instead of just using the link to the video on YouTube? The answer is a simple one: YouTube content can go away at any time. The original poster can take down the video, as can YouTube if it receives a copyright complaint about the video. If the content is short (less than 10 minutes, usually), you should be able to download the video as MP4 and then place it in Lessons or the Podcast tool in your site.

Capture and record video or video w. audio from your screen

CamStudio is a free recording utility (Windows only) that lets you make an instructional video with audio from your headset or microphone. Output is to AVI or Flash files (SWF), which can be used in Sakai. This free program has most of the features of commercial programs like Camtasia.
[Get CamStudio for PC | http://camstudio.org/]
The free Windows program ATube Catcher also has a screen capture utility that also captures audio.
[Get ATube Catcher (Windows only) | http://atube-catcher.dsnetwb.com/video/]

HTML Files (Web pages)

Using HTML files in Sakai

HTML files created in a web editor can be uploaded to Resources, and Sakai Lessons provides for import of an entire website if the files and folders are compressed into a ZIP file.
Since Sakai's built-in text editor has an HTML view mode, it is possible to create formatted HTML in a web editor and paste the HTML code into a Sakai text editor.
The built-in HTML editor in Sakai has a very limited feature set. For full HTML editing, use an application deisgned expressly for this purpose. A free program that is a full-featured web editor is Amaya, which was developed for the Worldwide Web Consortium for testing new features of HTML. Although this appplication has not been updated in three years, it is more than adequate for simple web page design and editing. A free download can be obtained at:
[Amaya Download | http://www.w3.org/Amaya/User/BinDist.html ]
Among commercial products for web editing, the best by far is Adobe Dreamweaver, which is always current with the latest developments in HTML, and which comes with a library of templates and examples. Dreamweaver is now part of the Adobe Creative Cloud suite of programs, so that anyone subscribing to Adobe Creative Cloud can download and run Dreamweaver. Academic discounts are available directly from Adobe. To get Adobe Creative Cloud:
[Adobe Creative Cloud | http://www.adobe.com/creativecloud.html]
A caution about HTML files in Sakai Resources. Although you can "edit" an externally-created web page in Resources using Sakai's built-in text editor, doing so is likely to strip out any custom CSS and formatting such as background colors. If you need to revise a web page you have placed in Sakai, do the revision in Amaya or Dreamweaver on the local copy of the files and then overwrite the files in Sakai.