Unit Four -- Video
Video, especially digital video, is becoming increasingly more
ubiquitous in our lives. Television, both the older analog form
and new digital/HD TV, are hugely popular. There are an enormous
number of movies coming out ever year. And over the last few
years, video has started to explode onto the web, led by sites like
YouTube, Vimeo, Metacafe, and many more. While it is very
difficult to get into the Televison or Movie industries, anyone can
quickly and easily upload a video to one of those websites and, if the
content and quality are good, get thousands or even millions of people
to see their video. This has opened up huge new opportunities for
sharing with family and friends, marketing to an audience, and even
creating a new show or film.
In this unit we will talk about how video works as well as how to
convert, trim, edit, and create it. We will focus on digital
video, that could be easily uploaded to one of the online sites, but
what we will learn could also easily apply to the television or movie
Section 1 - Video Storage
Section 2 - Formats
Section 3 - Quality
Section 4 - Conversion with Handbrake
Section 5 - Advanced Conversion with FFMpeg
Section 6 - Making Clips with Avidemux
Section 7 - Multi-Track Editing with Kdenlive
Section 8 - Screen Capture Video
Section 9 - DVD Creation
Section 10 - Live and Online Creation
Frame - One image of a video. Many of these are shown every second so
that video looks like it is moving.
Frame Rate - The number of frames of video shown each second.
Aspect Ratio - The ratio of the width of the image to the height of the
image. For modern video this is 16:9 or 17:9, for older video
this is usually 4:3 (the same as photographs).
Interlacing - When only half the lines of video are shown each frame.
This was done in older formats to lower then bandwidth needed but in
modern video degrades the quality.
Pixel Format - Unlike photographs where every pixel has one byte for
each of R,G,B; video usually uses more complicated, but smaller ways of
YUV - The type of pixel representation that is most often used in
video. The Y value is the luminance (or brightness), the U and V values
provide the color makeup.
Container - This is the name for how the frames of video, audio,
subtitles and other items are packed into a digital file.
Codec - Short for enCOder/DECoder. The codec is the mechanism that is
used to compress the video to a smaller size and to turn it back into
video when it is being watched.
Interframe Compression - When a Codec looks at future and past frames
of video to determine how to encode/decode the current frame of video.
This enables the codec to do a much better job at compressing areas of
the frame that haven't changed much since the last frame of video.
Bit Rate - The number of bits per second that are used to store the
audio or video as digital data.
Two Pass Encoding - In this type of encoding, the encoder runs through
the whole video a first time, to determine what areas are easier or
harder to encode. Then when it goes through a second time, it can use
more bits to encode the difficult parts and less for the easy parts.
This is a type of Variable Bit Rate (VBR) encoding.
Transition - A way of joining two parts of video together smoothly.
Jump Transition - The most common type of transition, where one clip
simply ends and the next one starts immediately.
Dissolve Transition - When one clip ends and slowly blends into the
Wipe Transition - When the video from one clip wipes the video from the
previous clip off the screen, using some sort of pattern (line, star,
circle, etc). This type of transition should be avoided.
Composite - Having two or more clips of video playing at the same time
in a video.
Green Screen - Also known as Blue Screen or Chroma Key, filming with
this enables the editor to remove the background (since it is all the
same color) and put in a different background.
Quiz (Sections 1-3)
1 - What is the most common wide screen aspect ratio?
2 - What was the most common video aspect ratio before the 1990s?
3 - What is the most common aspect ratio for professional films?
4 - Interlacing doubles the number of lines of video that are sent every frame.
5 - Interlacing makes digital video harder to compress and larger in size.
6 - What frame rate will we prefer to use in this class?
a) 23.976 fps
b) 24 fps
c) 25 fps
d) 29.97 fps
e) 30 fps
f) 48 fps
g) 60 fps
7 - What frame rate will provide the most natural looking picture?
a) 23.976 fps
b) 24 fps
c) 25 fps
d) 29.97 fps
e) 30 fps
f) 48 fps
g) 60 fps
8 - What frame rate will provide the lowest bit-rate
a) 5 fps
b) 24 fps
c) 30 fps
d) 48 fps
c) 60 fps
9 - What pixel format will we prefer to use in this class?
a) YUV 444
c) YUV 422
d) YUV 555
10 - How many bits doe YUV 422 use for each pixel?
11 - What open source, royalty free container format will we prefer to use in this class?
a) Audio Video Interleave (AVI)
c) QuickTime (MOV)
d) Matroska (MKV)
12 - MPEG 4 Containers support progressive downloading, where you can start playing the clip before it has finished downloading.
13 - WebM is a open source, royalty free container that is supported
natively by several web browsers, for use when putting video in
14 - Raw 1080p Video (YUV4:2:2, 30fps) uses approximately how much storage per hour?
a) 5 MB
b) 50 MB
c) 500 MB
d) 5 GB
e) 50 GB
f) 500 GB
g) 5 TB
15 - Which codec can usually compress video to the smallest size while keeping the quality of the video high?
a) MPEG 2
b) XviD (MPEG 4 Part 2)
c) H.264 (MPEG 4 Part 10)
16 - When running H.264 with the most agressive settings, it is
possible to compress 1080p video down to 2,000kbps (250KB/s) and still
have a good quality.
17 - Two pass encoding allows the codec to find areas that are hard to
compress the first time, then use extra storage space to compress them
the second time.
18 - For the WebM format, the WebM (a derrivative of Matroska) conainer
is used with the VP8 video codec and what audio codec to create an open
source, royalty free format for use in web pages?
Use Handbrake to re-compress this
video file into MP4, H.264, AAC with
Do not submit the final video, rather send: The settings used for audio
and video quality/bit-rate, the name of the output file, and the size
(in bytes) of the output file.
Use ffmpeg to re-compress this
video file with the MPEG 4 codec at
6000kbps with no audio.
Do not submit the final video, rather, copy and past the output from
the two following commands:
ls -l NameOfYourFile
ffmpeg -i NameOfYourFile
Use Avidemux to save (using MPEG4 ASP and MP3 codecs) only the section
video where the dragon is flying around the tower and grabs the
Submit the clip of video that you saved.
Edit the videos we took from Montero together to form an introduction
to the city. Add title slides where necessary. At the end provide
credits (filmed by Thomas Kent and Ana Beatriz Beltran Leon) and a
license for your film.
Render the file and show to the professor for grading.
Screen Grab Activity
Record a video of yourself opening one of the games from the
applications menu and playing it. As you do each step, explain what you
are doing. The video should be approximately thirty seconds in length.
Submit your Ogg/Theora Video file.
Final Activity - Video Tutorial Creation
For the final activity of the video section, you will be creating a
video tutorial of one of the previous sections, editing it, and
uploading it to YouTube. Pick from the following list of
activities/tools we have learned in
this class, and walk through using the tool explaining what you are
doing as you do it.
Gimp: rotate, crop, and resize
Gimp: remove redeye
Gimp: select an object to remove from the background
Gimp: use layers to add an object behind another object
Gimp: use the curves dialog to lighten one picture and darken another
Gimp: fix facial blemishes using the heal and smudge tools
Inkscape: create all the basic shapes
Inkscape: demonstrate beizer curves
Inkscape: explain z-order and selection
Inkscape: make text follow a path
Dia: create a basic flowchart
Audacity: record Audio
Audacity: cut and add silence to tracks
Audacity: align multiple tracks
Audacity: remove background noise from a track
Audacity: add amplification and fade in/out a track
Handbrake: converting a video
FFMpeg: converting a video
Avidemux: clipping a section out of a video
Kdenlive: adding videos to the project and the timeline
Kdenlive: using the clip monitor to add a portion of a video to the
Kdenlive: using the dissolve and fade transitions
Kdenlive: compositing multiple videos on the screen
Once you have recorded all your clips in the desktop recorder, use
Kdenlive to edit them together into one video. Finally add a title at
the beginning of the video with an introduction to your tutorial and
another at the end giving yourself credit as well as providing
attribution for any other works (images, audio, etc) you have incorporated into your video and a license for your work.
When your video is complete, render it in a format that is suitable for
uploading to YouTube and write down all the other information for
youtube (title, description, tags, etc).
Submit your information with this assignment and work with the teacher
to upload your video to YouTube.
PiTiVi - Ubuntu standard, not as full-featured
Cinelera - Very full featured, complicated to use
K9copy - Great for making images of DVDs
Kino - Useful for working with DV cameras
Blue Sky, Taurus Media Technik, http://media.xiph.org/video/derf/,
Riverbed, Taurus Media Technik, http://media.xiph.org/video/derf/,
Sintel Trailer, The Durian Open Movie Project, http://media.xiph.org/sintel/,