Example 2

1. Example 2 A student captured a video clip from a digital video camera and it was then transferred to a computer. The video clip was stored as an uncompressed AVI file. The characteristics of the video clip are shown below. (a)Calculate the memory required (in MB) for storing one video frame of the clip. (b)Calculate the file size (in MB) of the video clip. (c)When the student played the video clip, the motion was not as smooth as when shown on the monitor. Explain two reasons for the problem. Frame size = 320 × 240 pixels Frame rate = 20 fps Duration = 10 seconds Colour depth = 24 bits / pixel

2. Example 2 Solution (a)Memory required for storing one video frame = 320 × 240 × 24 = 1,843,200 bits = 230,400 byte = 0.22 MB (b)File size of the video clip = 10 × 20 × 0.22 MB = 43.95 MB (c)‧The computer was not powerful enough to play the large video file smoothly. ‧ The frame rate was too low.

3. Example 2 Solution (a)Memory required for storing one video frame = 320 × 240 × 24 = 1,843,200 bits = 230,400 byte = 0.22 MB (b)File size of the video clip = 10 × 20 × 0.22 MB = 43.95 MB (c)‧The computer was not powerful enough to play the large video file smoothly. ‧ The frame rate was too low.