IBM ThinkPad 760CD, Руководство пользователя

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Using the Video Functions
17
Choose Build from the Video menu, or click on the Build
button (the sixth button from the top on the toolbar). Enter the
name and location of your final .AVI file (making sure to keep
the .AVI extension); then click on Build.
The Build Progress dialog box opens, so you can look at the
percentage-complete bar and the preview window to track the
progress of the build. Building a video can take anywhere from
a few minutes to several hours, depending on its length and
complexity, and on the type of compressor you choose. This
procedure should take approximately 14 minutes.
Calculating Hard Disk Space:
You can easily calculate the amount of
hard disk space you need to capture a video clip using the following
formula:
Frame size (pels per frame)
×
Color depth (bytes per pel)
×
Frame rate
×
Number of seconds = Video in bytes
Sampling size (bytes per channel)
×
Number of channels (channels per
sample)
×
Sampling rate
×
Number of seconds = Audio in bytes
Video in bytes / Audio in bytes = Amount of hard disk space in bytes
For example, we calculated the space you need to capture the file
example as follows:
(160
×
120 pels/frame) (2 bytes/pel) (15 frames/second) (30 seconds) =
17 280 000 bytes of video
[(8 bits/channel) (1 byte/8 bits)] (1 channel/sample) (11 025
samples/second) (30 seconds) = 330 750 bytes of audio
17 610 750 bytes/1 048 576 bytes = 16.794 megabytes
If, when you follow the procedure, you want to capture more or less
than 30 seconds of video and audio, you can adjust how much hard
disk space to allocate by substituting the number of seconds you
plan to capture in the preceding calculation.
Chapter 3. Operating Your Computer
95
Title: C78TFMST CreationDate: 07/11/95 14:33:57