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If you want to get video clips onto your computer, you need extra hardware in the form of a card or some other attachment that plugs into your computer. The commonest type is a video grabber card which slots inside your computer and this comes with some means of connecting the video output cord from a video tape recorded or camera to the video grabber card. Video cards can vary in price from inexpensive to the high end expensive ones. With the higher end cards, you don't necessarily need a fast computer to grab videos, but if you are into grabbing videos, having a fast, powerful computer helps a great deal with what you may want to do with the grabbed video clip. My early video grabs, were done on a Pentium 100 MHz PC with just 16 MB of RAM and a Creative Labs SE 100 frame grabber card. Although the SE 100 was designed merely to display video on the PC and grab single frames, a Microsoft freeware utility called VidEdit can be downloaded and used to grab motion video clips. Videos and movies consist of a series of single images that are displayed one after another in such quick succession that the eyes get the impression of a moving image. The smooth, seamless scenes you see on TV, or in a movie are the result of the projection of 25 to 30 pictures (called frames) per second. If you know that a single picture stored on the hard disk of your computer occupies far more space than several pages of text, is is easy to understand that storing 30 pictures for every second of video, or thousands of frames for a few minutes of video can occupy huge volumes of disk space. So the other thing that you need is a biggish hard disk - and I would recommend at least 500 MB of free disk space for playing with short video grabs, and many gigabytes more if you are planning seriously long videos. STEP 2 : STORING THE VIDEO Once the video is grabbed, it needs to be stored on your hard disk as a file. These video files are stored in standard formats bearing recognizable filename extensions. For example, the Microsoft video format are avi files - they are stored as "filename.avi". Mac users will be familiar with the mov format, and another commonly used format is the mpeg format (motion picture experts group) - and these files have the extension mpg. If you look on a video CD - you will find a file ending with the extension "dat" - also an mpeg file containing details of the movie on that CD. Other formats exist, including the Real Audio or Video files that you may have viewed on an internet news site with the extension ra. Since one second of video occupies 1-2 MB of disk space, a lot of effort needs to go into reducing the file size of the video into something that is less of a memory hog, and this is certainly required if the file has to go up on the internet and be accessible to a wide variety of people - some of whom may have slow modem lines. For this reason some video formats mentioned above use CODECs - software COmpressor-DECompressor methods to make huge video files smaller. Well known codecs for the Microsoft avi format are the Microsoft avi codec, Intel Indeo and the Cinepak codec. The Cinepak codec probably gives the best compression while retaining the best quality. Mpeg files achieve the highest compression while still retaining quality - and these are becoming standard. An uncompressed video clip that occupies 20 MB may be compressed down to 1 MB using the mpeg standard. STEP 3: MANIPULATING AND EDITING THE VIDEO Very often, the hardware that you buy to grab videos comes bundled with software that enables you to store and edit video files perhaps in the avi or mpeg format. The necessary codecs come with the package. But the net offers some super freeware utilities that can be used to grab and store video clips You can use these utilities to edit, clip, join, splice, add and delete sound, add special effects and generally try to make a Steven Spielberg out of yourself. Click here for a few links.
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