1. "Digital Media Primer" Yue-Ling Wong, Copyright (c)2013 by Pearson Education, Inc. All rights reserved.

2. Chapter 6 Fundamentals of Digital Video
Part 4
Digital Video File Types

3. How to calculate the video frame size. https://www. omnicalculator
once you know the resolution and color depth, you can find the frame size according to the following equation:
frame size = V * H * CD
where
V is the vertical resolution,
H is the horizontal resolution, and
CD is the color depth

4. video size = frame size * fps * time where
time is the duration of the video, and
fps is the number of frames displayed per second. This number can range from 12 fps to even 60 fps; the most common value, however, is 24 frames per second.

5. The 1-second Video 1440  1080 pixels 24-bit color 30 fps
1 second long
Audio: stereo (2 channels)
Audio: 48 kHz, 16-bit

6. File Size Calculation The picture component:
Total pixels in each frame: 1440  1080 pixels = 1,555,200 pixels/frames
File size of a frame: 1,555,200 pixels/frames  24 bits/pixel = 37,324,800 bits/frame
File size of 30 frames (1 second): 37,324,800 bits/frame  30 frames = 1,119,744,000 bits

7. File Size Calculation
1,119,744,000 bits = 1,119,744,000 bits / (8 bits/bytes) = 139,968,000 bytes  133 MB

8. File Size Calculation
Audio: Sampling rate  length of the audio  bit-depth  number of channels = 48,000 samples/sec  1 second  16 bits/sample  2 = 1,536,000 bits = 1,536,000 bits / (8 bits/byte) = 192,000 bytes  188 KB

9. File Size Calculation
Total file size of this 1-second uncompressed video = size of the picture component + audio size  133 MB KB = 133 MB 10 seconds would be 1.33 GB!

10. Data Rate
Amount of video data to be processed per second

11. General Strategies for Reducing Video Data Rate
Basic ideas: A video is a sequence of images + audio Apply strategies for reducing digital image and audio file size.

12. General Strategies for Reducing Video File Size
General Strategies for reducing digital image file size
reduce frame size
reduce frame rate
choose a video compressor that allows higher compression
choose the lower picture quality option
Reduce duration of the video so you have less frames
not always possible
will not impact data rate

13. Why General Strategies for Reducing Digital Image File Size Work for Video
Reduce frame size because:
you have less pixels for each frame
Reduce frame rate because:
you have less frames
Video compression with high compression because:
some data are discarded
Lower picture quality option because:

14. Review Questions Note to instructor:
Depending on your preference, you may want to go over the review questions at the end of this lecture as an instant review or at the beginning of next lecture to refresh students' memory of this lecture.

15. Review Question
True/False: A long video, even with low data rate, can have a large file size.
True

16. Review Question
Name several strategies to reduce the file size of a video.
reduce frame size
reduce frame rate
higher compression
lower picture quality option if available
reduce the duration of the video