Multimedia Basics
http://www.techterms.com/definition/multimedia
As the name implies, multimedia is the integration of multiple forms of media. This includes text, graphics, audio, video, etc. For example, a presentation involving audio and video clips would be considered a "multimedia presentation." Educational software that involves animations, sound, and text is called "multimedia software." CDs and DVDs are often considered to be "multimedia formats" since they can store a lot of data and most forms of multimedia require a lot of disk space.
OR
http://dictionary.reference.com/browse/multimedia
File Types
Before even considering what file types relate to Multimedia, you need to understand the concept of what a file type is.Back in the old days of DOS, computer filenames were restricted to 8 characters, plus a dot separator, plus a 3 letter file extension (8.3 naming convention). That is now much higher, although the full path and filename must not exceed 260 characters.
A filename can include any character or number but may not include the following characters:
< > : " / \ | ? *
The file extension is used by the operating system (such as Windows 7 or 8) to determine the file type. Windows then uses this file type to associate the file with a particular software application. When you select a file and open it, the associated software application will be used. Windows will also use an icon with the file name that will let you know what the default application for that file is.
The above image shows some files that are in My Documents. You can see that Windows has associated a software application with each file type that it can identify.
Office Applications
Common file extensions for Office applications are:
Microsoft Word .doc .docx .dot .dotx (templates)
Microsoft Excel .xls .xlsx
Microsoft Access .mdb .mdb .accd
Microsoft PowerPoint .ppt .pptx
Rich Text format .rtf
Text .txt
Open Office .odt .odb .ods
Audio Files
Audio Interchange File Format .aif
Interchange File Format .iff
Media Playlist file .m3u
MPS Audio File .mp3
MPEG-2 Audio File .m4a
WAVE Audio FIle .wav
Windows Media Audio file .wma
iTunes audio .m4p
Video Files
Audio Video Interleave File .avi
Flash Video File .flv
Apple QuickTime movie .mov
MPEG-4 Video file .mp4
MPEG Video file .mpg
DVD Video Object File .vob
Windows Media Video File .wmv
Flash Shockwave file .swf
Raster/Bitmap Image Files
Bitmap Image File .bmp
Graphical Interchange format file .gif
JPEG Image .jpg .jpeg
Portable Network Graphic .png
Adobe Photoshop Document .psd
Tagged Image File .tif .tiff
Vector Image Files
Adobe Illustrator File .ai
Encapsulated Postscript File .eps
PostScript File .ps
Scalable Vector Graphics File .svg
Multimedia File Type Details
MPEGMPEG is the Moving Pictures Expert Group - a working group that is part of ISO. Its role is to develop audio and video encoding standards. The file format is named after this group.
MPEG-1 is the first generation of the MPEG format. The quality of this equates to that of a VHS Tape
MPEG-2 provides a better quality than MPEG-1. It supports a higher image resolution, better quality coding and supports multi-channel audio. It was developed to the standard of the DVD.
MPEG-3 is an audio file format. It produces compressed audio that is equivalent to CD quality sound. It is also referred to as MP3.
MPEG-4 is higher quality again. This file format has a high level of compression creating even smaller files, but supports 3D content and video files of a very high quality.
AVI and MOV
are container files for Microsoft , utilising a variety of codecs. Just because you were able to play one AVI file, doesn’t mean that you can play another one as it may have been compressed using a different codec.
WMV
this is the standard file format to be played with Windows Media Player
FLV
Flash Video
But what you see isn’t always what you get as there are so many variations on the codecs used for each of these.
Here are a few articles that may help unravel the mystery (or just make it more mysterious).
http://www.videomaker.com/article/15362-video-formats-explained
http://www.dr-lex.be/info-stuff/mediaformats.html
http://www.pcworld.com/article/199274/video_formats_explained.html
http://www.masternewmedia.org/the-video-encoding-guide-codecs-formats-containers-and-settings-explained/
and High Definition
http://en.wikipedia.org/wiki/High-definition_video
Image Formats
GIF This stands for Graphic Interchange Format. GIF files are best for flat or simple graphics that contain solid areas of colour such as logos and line art. GIF also supports transparency and animation.JPEG This stands for Joint Photographic Experts Group. JPEGs are best for continuous tone images such as photographs or graphics that contain gradients.
PNG This stands for Portable Network Graphics. PNG file type is best used for true colour images containing text and sharp colour transitions. Ideal for maps, charts and diagrams with more than 256 colors. This format also supports transparency
SWF These are Macromedia Shockwave files or Flash files. This file format also supports transparency and animation.
http://windows.microsoft.com/en-au/windows/understanding-picture-file-types#1TC=windows-7
Lossy or Lossless
Lossy compression reduces the file size by discarding some visual information. Lossless compression reduces the file size without discarding visual information. JPEG is a lossy compression method, whereas GIF is not.
Bit Depth
Bit depth relates to the number of colours in an image. GIF is an 8-bit file format and JPEG is 24-bit.
32-bit 16.7 million colours plus an 8-bit alpha channel
24-bit 16.7 million colours
16-bit 65,600 colours
8-bit 256 colours
7-bit 128 colours
6-bit 64 colours
5-bit 32 colours
4-bit 16 colours
3-bit 8 colours
2-bit 4 colours
1-bit 2 colours
Pixels and Resolution
It's all about the Pixels
You have all heard the term, but what actually is a pixel. This definition is from http://www.techterms.com/definition/pixel and defines the term in plain english.The term "pixel" is actually short for "Picture Element." These small little dots are what make up the images on computer displays, whether they are flat-screen (LCD) or tube (CRT) monitors. The screen is divided up into a matrix of thousands or even millions of pixels. Typically, you cannot see the individual pixels, because they are so small. This is a good thing, because most people prefer to look at smooth, clear images rather than blocky, "pixelated" ones. However, if you set your monitor to a low resolution, such as 640x480 and look closely at your screen, you will may be able to see the individual pixels. As you may have guessed, a resolution of 640x480 is comprised of a matrix of 640 by 480 pixels, or 307,200 in all. That's a lot of little dots.
Each pixel can only be one color at a time. However, since they are so small, pixels often blend together to form various shades and blends of colors. The number of colors each pixel can be is determined by the number of bits used to represent it. For example, 8-bit color allows for 2 to the 8th, or 256 colors to be displayed. At this color depth, you may be able to see "graininess," or spotted colors when one color blends to another. However, at 16, 24, and 32-bit color depths, the color blending is smooth and, unless you have some kind of extra-sensory vision capability, you should not see any graininess.
Image Resolution
So why is resolution important? Depending on the what you will use the images for, you may need a higher resolution or a lower one. If you wanted to create a large poster, you need high quality images i.e. images with a very high resolution. If you are creating thumbnails for a web based image gallery, then the size of the image is not so important and you would probably want a lower resolution so that they load up quickly.If you increase the size of an image with a low resolution, you will start to see the blocky pixels. It is best to get an image with a higher resolution and reduce the size. Here is an example:
The first image is at its full resolution 3648 X 2736 and is 3.74mb. On a side note - this file took ages to upload into Blogger.
This is displayed at Blogger's "Large" size.
The following is the exact same image, but displayed in Blogger at "Original Size"
This is the same image that I have reduced to 150 pixels wide X 113 high, displayed at "Large" size
and the same image at "Original Size"
When you search for images on the Internet, as well as Copyright issues, you also need to consider the resolution of the images. We won't go into Copyright at the moment - I have to leave some excitement for the afternoon classes.
Creating a simple Photo Slide Show
As you are already familiar with PowerPoint, we will use this to see how we can use images to create a presentation. PowerPoint calls it a Photo Album.Selecting your images
To create our photo album, we need to find some images. I am using Firefox and Google Images for this exercise.I want to do my slideshow on "Dog Shaming" as there is nothing more cute than dopey dogs who are feeling guilty.
Step 1: Find some good quality images. My screen resolution is 1920 X 1080.
I put "Dog Shaming" as my search criteria. The result was lots of images and many different resolutions.
Step 2: Create the Photo Album
EXERCISE
- Pick a topic and download some good quality images
- Create a Photo Album using PowerPoint
- Share with your classmates.
Creating a Video
It hasn't been that long, so I don't think I need to show you how to do transitions for a presentations.
If you would like to have some music playing, you can add an audio track. I am using PowerPoint 2016 on my home computer.
Once you are happy with your masterpiece, you can turn it into a video.
To Create a Video from your presentation, use the Export option.
EXERCISE 2
- Apply transitions and timings for your photo album
- Add some Music
- Save your Photo Album as a video
- Share on Facebook
http://freemusicarchive.org/
Here is my VERY VERY quick photo album without any bells and whistles, but with a soundtrack, just using some basics photos from my computer.
And Slightly "Tweaked" version!
No comments:
Post a Comment