This document discusses subtitles, including the different types (real-time, offline, soft, built-in, hard), file formats, and the technical aspects of video processing like frame rate, aspect ratio, resolution, and compression. It also covers software and hardware requirements for encoding subtitles, how to configure subtitles, and examples of using subtitles.

1. Subtitle
Vuong Ngoc Anh
BIT1SN
IT Field Today

2. Subtitle (captioning)
 The texts are displayed on the screen to:
 Support people of different language or
disable to hear.
 May contain effects to make the
movie/music video more attractive.

3. Types of subtitle
 Real-time captioning: are created and
added during live broadcasts or events.
 Offline captioning: are created and
added after a production has been
recorded and before it is aired or played.

4. Soft
• Separate subtitle file.
• Located at the same
folder with video file.
Built
- in
• Embedded into video
file.
• Users can switch on
and off.
Hard
• Embedded into video
file.
• Appeared concurrently
with video file

5. Soft subtitle
 Frame rate: how fast a new still image is
available, measured in frame per second.
Clip: Flip book animation
 Character encoding:
 ASCII: American Standard Code for
Information Interchange, based on English
alphabet.
 UTF-8: UCS Transformation Format-8 bit:
represent characters in the Unicode
character set.

6. Hard subtitle

7. Complete subtitled movie
Subtitle
Audio
Video

8. Processing video file
 Sampling and quantization.
 Bit depth: the number of possible levels.
 Aspect ratio: ratio of the width of the picture
to the height (e.g.: 4:3; 16:9, etc.)
 Frame size/resolution: is measured in pixel
dimension of a frame (e.g. 720x576 pixels).
 Video compression: the process of converting
digital video into a format suitable for
transmission or storage which contains a small
amount of bits.

10. ?????

11. Video conversion
 The process of preparing the video for
output, where the digital video is
encoded to meet proper formats and
specifications for recording and playback
through the use of video encoder
software.
 E.g.: convert from .mkv movie file to .avi
movie file.

12. Pixel aspect ratio
 Digital image editing: use square pixels by
default, some video formats use non-square
pixels to make up the frame.
 Pixel aspect ratio: The ratio of pixel’s width
to its height.
 Square pixel: 1
 Standard Digital Video format: 0.9
 Wide-screen Digital Video format: 1.2
 Width: height = 720 x 1.2 : 480 ~ 852 : 480 ~ 16:9

13. Counting time
 Timecode: is used to number frames.
 SMPTE (Society of Motion Pictures and
Television Engineers) video timecode, the
most common timecode for digital video,
numbers frames in hours, minutes,
seconds, and frames.
 Timing:

14. 1 minute, 54 second, and 140 frames

15. Hardware for encoding
 Minimum: Pentium IV 2.0 Ghz, RAM 512
MB, card onboard.
 Suggest: Intel celeron, RAM 1GB 3.0 Ghz,
card 8500GT.
 Ideal: Intel Core 2 Duo 3.0 Ghz (x2), RAM
2GB, card Gefore 9600 GT or above.

16. Software requirements
 Directly add subtitles while editing movie:
Adobe Premier, Magix Movie Editor, ProShow
Producer, etc.
 Timing and typesetting: Aegisub, Subtitle
Workshop, etc.
 Encoding video: MeGUI, VirtualDub, StaxRip,
etc.
 Other tools to read and process different video
formats: Avisynth, K-Lite Codec Pack, .NET
Framework, NerAacEnc etc.

17. Subtitle configuration
 What you can do with subtitle?
 Shift time to fit the original movie.
 Turn on and off with built-in subtitle:
Youtube Close Caption, television.
 Add effects (Typesetting).

18. Example
 Remember when (“Up” Original
Soundtrack)

19. References
 Wong, Y.-L. (2009). Digital Media Primer: Digital Audio,
Video, Imaging and Multimedia Programming. Upper
Saddle River (NJ) : Pearson, Prentice-Hall.
 Berke, J. (2010, 26 2). Deafness. Retrieved 2 19, 2012, from
About.com.
 Peters, O. (2003, December 18). A Different Drummer -
Understanding Frame Rates and Timecode. Retrieved
January 13, 2012, from digitalfilms.wordpress.com.
 Typesetting. (n.d.). Retrieved December 13, 2012, from
Aegisub Manual.
 How to add Subtitles to your videos on YouTube (easy)
1080p HD

20. References
 Richardson, I. (2010, May). H. 264 Advanced Video
Compression Standard. (2). Hoboken, New Jersey,
USA: Wiley.
 Clark, J. (1994, July). Reading the silver screen.
Technology Review.
 Jack, K. (2008). Digital Video and DSP. Elsevier Inc.
 Nowlin, D. (2009, June 19). Video Frame Display
Synchronization. Retrieved January 13, 2012, from
Intel.
 Silva, R. (2012, January 13). Video Resolution - An
Overview - What You Need to Know About Video
Resolution. Retrieved January 13, 2012, from
About.com Guide.