PDF of this tutorialVideo Capture
The next step in the process is to capture, record, and create the content. The video could come from several different sources: live recordings from a Web camera, prerecorded video from a video cassette recorder (VCR) or camera, or video that has already been converted to a file format, such as .avi or QuickTime.
If video is captured from a camera or a VCR, it must be of the highest possible resolution. This will take more disk space, but because the quality of the presentation will begin to suffer as it is encoded for streaming, starting with a great-quality product will improve the chances for a good-quality product when the project is completed.
To capture the video, a video-capture card is necessary. There are basically two types: one will capture from an analog tape deck or camera, and the other will capture from digital video decks and cameras using an Institute of Electrical and Electronic Engineers (IEEE) 1394 interface. IEEE 1394 is commonly known as FireWire but is sometimes referred to as I-Link or Lynx. This interface is capable of data transfer rates of up to 400 Mbps, so it is perfect for handling the enormous amount of data needed to represent video. Both analog and digital cards capture the video in real time.
Most of these cards will come with a video capture–software utility. In most cases, the video will be compressed as it is captured. To capture uncompressed video, the system must be capable of transfer rates of 22 Mbps; however, this is out of the reach of the normal user. In most cases, the capture card will perform compression. This is known as hardware compression (as opposed to software compression). Hardware compression is faster, as it does not depend on the computer’s processing power.
Many of the capture utilities that come with the capture cards will allow the creation of a batch capture list. This process involves previewing the videotape and controlling the video camera or playback deck by using the controls provided in the capture software. As the tape is previewed, in and out points may be marked to select the various scenes one wishes to use in the final production. The software will then automate the process of capturing those shots. This saves a great deal of drive space, as only the necessary video is captured.
Audio Recording
As the video is captured, the audio that was recorded in the camera will be captured as well. However, in most cases, additional audio will be needed. In some cases, the audio that was recorded at the time of the video shoot was compromised by uncontrollable circumstances. For example, perhaps noise from a passing car or a plane or from a loud air-conditioner or fan in the room was recorded. In such cases, the audio may need to be rerecorded in an environment such as a sound studio, where extraneous noise may be controlled.
In other cases, a narration to accompany the video must be recorded. The narration may need to be recorded and edited before the video-editing process is begun, in which case the video is then edited to the audio. Sound effects and music must also be recorded to accompany the video.
In all of these cases, the audio—like the video—should be recorded at high resolution. If the audio is being recorded to a digital audio tape (DAT) recorder or a hard-disk system, it must be done at compact-disc (CD) quality. This requires a sampling rate of 44.1 kHz and a bit depth of 16. As with video, quality will be lost when the content is compressed for Internet delivery; thus, one must start with the best possible product.
