Images
Images are the most simple form of multimedia content. The two main types of images are raster graphics and vector graphics. Raster graphics use a lot of dots, called a "bitmap", to make a photograph. These dots are called pixels and are colored with a certain depth. Basic raster graphic images can be extremely large. There are two different forms of compression to make these images smaller. Lossless compression is a term that means having the same image quality without losing any data. This would be ideal if you later plan on editing the image. In lossy compression, some data is lost but not enough for many people to notice. A time when lossy compression would be used is if you were planning on delivering that image to a website. A major problem of using raster graphics is the image gets skewed if you try to make it larger.
Here is an example of a raster graphic image. This is a small picture of myself taken from nbadraft.net. When trying to enlarge the photo, the quality of the photo is sacrificed and the resulting image is blurred.
Here is an example of a raster graphic image. This is a small picture of myself taken from nbadraft.net. When trying to enlarge the photo, the quality of the photo is sacrificed and the resulting image is blurred.
Vector graphics uses primitives-geometrical objects that are expressed mathematically. This enables you to zoom in and out without sacrificing quality. There are times when a raster graphic is your best choice, and times when a vector graphic is your best choice. There will also be times when the two will come together and complement each others functions.
There are a few ways to go about creating images. The main way is by using an external device such as a digital camera, a webcam, or a scanner. Another way is by using a screen cap. This is exceptionally useful if trying to show your customers how to do something on a computer. Images are the most simple form of multimedia. Now let's take a look at the audio branch of multimedia and how it can be used in the business world.
Audio
If audio files are not compressed, they can be extremely large. When comparing the two forms of compression it is extremely similar to image compression. If you use lossy form of compression, it will generally sound the same, but throws away some of the audio data.However, lossless compression will make it about 50% smaller without losing any data. For music, you want higher quality so the size is going to be bigger.
There are six different types of audio file formats.
1. WAV- "Waveform Audio File Format" Which is not compressed
2. AIFF- "Audio Interchange File Format" Also not compressed
3. WMA- "Windows Media Audio" Compressed, won't play on an Ipod, but has digital rights management.
4. MP3- "MPEG-1 Audio Layer 3" High levels of compression (Lossy)
5. AAC- "Advanced Audio Coding" Widely found on Apples and Ipods.
6. Apple Lossless and FLAC 50% compression
Digital rights management "DRM" places limitations on the way people can use files. They do this by setting an expiration date, or limiting the ways the file can be used. Another way is by placing a digital watermark on the audio. This helps show who exactly purchased the file in the beginning. If a file is "DRM" protected, sometimes people take the analog output, and record it to a different computer without a watermark or expiration date. The term for this is an "analog hole".
If you want to create audio, it is simple and cheap. You need an audio microphone and audio adapters. Most audio microphones are cheap and can accomplish what they are needed for. Here is an example of what a computer microphone might look like.
This hardware will then mix with software (also free), and can be edited. There are a few different types of software that enable the recording and editing process. Here is a link to the main software used in audio, Audacity.
Audio is a little more complex than images, but creating audio can be simple and enable business users to instruct employees verbally, and record messages to send to customers.
Video
Video is the most complex form of multimedia. Video is just still images playing rapidly in a sequence, called motion pictures. As in audio, CODEC is also used to code, and decode the files. It's important to make sure the company and it's customers have the same CODEC.
The main properties you need to consider when discussing video are as follows:
1. Aspect ratio- Width:height
-Tv is 4:3
-Widescreen 16:9
2. Resolution
- 480p is standard
-720p is HD
-1080p high quality
3. Frame Rate
-24 to 30 range is ideal, higher is smoother
4. Bit Rate
-Combination of aspect ratio, resolution, and frame rate.
If you have a video that you are later wanting to edit, you should use lossless compression or uncompressed video. If you are distributing the video to customers you should definitely compress the video.
Video Formats
1. AVU- "Audio Video Interleave" webcams, no compression
2. WMV- "Windows Media Video" WM8 and WM9
2. MOV- "Quick Time Movie" Lossy or lossless
4. MP4 and H.264
5. Screencast doesn't use video camera, uses computer screen to make video.
Creating Videos
As with audio, you will need both hardware and software to create a video. For hardware, you will need a camcorder with FireWire, USB connection, disk, or flash memory storage. There are many different types of software available depending on your purpose for the video. There is software for basic uses such as Apple iMovie, and Windows Movie Maker. For more extensive uses, there are software programs such as Apple Final Cut and Adobe premier.
Multimedia is media that uses multiple forms of information content and information processing such as text, audio, graphics, and animation to inform an audience. Multimedia is used in many areas but most applicable here would be in the business environment. I hope after reading this tutorial, you have a better understanding of the different types of multimedia and their various uses.
No comments:
Post a Comment