Uploaded by Not Rolando Dala (rndl_0126)

Video-Editing Techniques

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V204.03
Summer workshop-Guildford County,
July, 2014
 Creating an animation
using a program such as
3D Studio Max or
trueSpace is often just a
part of a total video
production process.
 Video editing software
(such as Adobe Premiere)
offers the opportunity to
enhance animation
productions with sound,
still images, and scene
transitions.
 The addition of sound
can add realism and
interest to a video
production.
 Titles and single images
(static or scrolling)
provide additional
information.
 Analog (linear) devices record light and sound as
continuously changing electrical signals described
by a continuous change of voltage.
 Digital recordings are composed of a series of
specific, discrete values which are recorded and
manipulated as bits of information, which can be
accessed or modified one bit at the time or in
selected groups of bits.
 Digital media is stored in a
format that a computer can read
and process directly.
 Digital cameras, scanners, and
digital audio recorders can be used
to save images and sound in a
format that can be recognized by
computer programs.
 Digital media may come from
images created or sound recorded
directly by computer programs.
 Analog media must be digitized or converted to a
digital format before using a computer
 Analog images may be obtained from such sources as
older video cameras working with VHS or SVHS. Analog
sounds may come from sources such as audiotapes and
recordings.
 Hardware devices such as a video capture card must be
attached to the computer to bring analog materials into
computer video editing programs.
Digital Versus Analog
 Sufficient computer
resources are needed for
digital video editing.
 Fast processors
needed to process the
video.
 Additional RAM
beyond customary
requirements is
needed.
 Very large hard drives
are needed. Few minutes
of footage require vast
amounts of storage.
 Video cards should be
capable of working with
24-bit color depth
displays.
 Large monitors are better
due to the need to work
with numerous software
displays.
 Selecting settings can be a
complex task requiring an
understanding of input resources
and output goals.
 The ability to make good
decisions regarding capture,
edit, and output settings require
an understanding of topics such
as frame rates, compression, and
audio.
 Numerous books can help but
Experience is still a really good
teacher.
 Timebase specifies time
divisions used to
calculate the time
position of each edit,
expressed in frames per
second (fps).
 24 is used for editing
motion-picture film
 25 for editing PAL
(European standard)
 29.97 for editing NTSC
(North American
standard) video
(television)
 Frame rate indicates to the
number of frames per second
contained in the source or the
exported video. Whenever
possible, the timebase and frame
rate agree. The frame rate does
not affect the speed of the video,
only how smoothly it displays.
 Timecode is a way of specifying
time. Timecode is displayed in
hours, minutes, second and
frames (00;00;00;00). The
timecode number gives each
frame a unique address.
 Frame size specifies the dimensions (in pixels) for frames.
Choose the frame size that matches your source video.
Common frames sizes include:
 640 x 480–standard for low-end video cards
 720 x 486–standard-resolution professional video
 720 x 480–DV standard
 720 x 576–PAL video standard (Used in Europe.)
 Aspect ratio is the ratio of width to
height of the video display.
 Pixel aspect ratio is the ratio for a pixel
while the frame aspect ratio is the width to
height relationship for an image.
 4:3 is the standard for conventional
television and analog video.
 16:9 is the motion picture standard.
 Distortion can occur when a source image has
a different pixel aspect ratio from the one
used by your display monitor. Some software
may correct for the distortion.
 CODECs (compressor/decompressor) specify the
compression system used for reducing the size of
digital files. Digital video and audio files are very
large and must be reduced for use on anything
other than powerful computer systems. Some
common CODECS include systems for QuickTime or
Windows.
 QuickTime (movie-playing
format for both the Mac and
Windows platform) - Cinepak,
DV-NTSC, Motion JPEG A and B,
Video
 Video for Windows (movieplaying format available only
for the Windows platform) –
Cinepak, Intel Indeo,
Microrsoft DV, Microsoft Video1
 Color bit depth is the number of colors to be included.
The more colors that you choose to work with, the larger
the file size and in turn, the more computer resources
required.
 8-bit color (256 colors) might be used for displays on the Web.
 24-bit color (millions of colors) produces the best image quality.
 32-bit color (millions of colors) allows the use of an alpha channel
.
 Audio bit depth is the
number of bits used to
describe the audio sample.
 8-bit mono is similar to FM
radio
 16-bit is similar to CD audio
 Audio interleave specifies
how often audio information
is inserted among the video
frames.
 Audio compression
reduces file size and is
needed when you plan to
export very large audio
files to CD-ROMs or the
Internet.
 Audio formats include
WAV, MP3, and MIDI
files. MIDI files do not
include vocals. MPEG
files can also include
audio.
 Visual and audio source media are referred to as clips,
which is a film industry metaphor referring to short
segments of a film project.
 Clips may be either computer-generated or live-action
images or sounds that may last from a few frames to
several minutes.
 Bins are used store and organize clips in a small screen
space. Bin is another film industry metaphor, which is
where editors hung strips of film until added to the
total production.
 Opening and viewing clips
 Images must be in a format that the video editing
software can recognize such as an avi (for animation),
wav (for sound), or jpg (for still image) before it can be
imported.
 Many software programs provide both a “source” window
and a separate “program” window where the entire
production can be monitored.
 Sound clips may be displayed as a waveform where
sounds are shown as spikes in a graph.
 Playback controls are a part of most viewing windows.
Play, Stop, Frame back, frame forward are typical of
window commands.
 The Timeline helps cue the user as to the relative
position and duration of a particular clip (or frame)
within the program by graphically showing the clips as
colored bars whose length is an indication of the
duration. As clip positions are moved along the
timeline, their position within the program is changed.
 Typically the timeline will include rows or individual
tracks for images, audio, and scene transition clips.
The tracks often include a time ruler for measurement
of the clips duration.
 Some programs allow the duration of a clip to be
changed by altering the length of the bar representing
the clip. Scenes within the program may be slowed or
the speed increased using this stretch method.
 Cutting and joining clips
 Software tools are typically
available for selecting a clip on
the timeline and then cutting the
bar that represents the clip. Using
this process, segments of “film”
may be separated, deleted,
moved, or joined with other clips.
 Cutting and joining may be used
on audio or video.
 Transitions allow you to make a gradual
or interesting change from one clip to
another by using special effects.
 Transitions might include dissolve, page
peels, slides, and stretches.
 The number and types of transitions
available depend upon the software you
are using.
Audio mixing is the process of making
adjustments to sound clips.
 Title clips
 Alpha channel allows you
superimpose the title
 Title rolls allow text to
move from the bottom of
the screen to beyond the
top used for credits.
 A title crawl moves the text
horizontally across the screen.
News bulletins along the bottom
of the television are an example
of this type of effect.
 Text and graphics may be created
in other programs and inserted.
Video editing programs are
usually limited in their ability to
create and manipulate text and
graphics.
 By using layering techniques, adjusting opacity, and
creating transparency, composite clips can be created.
 Bluescreen (greenscreen) and track hierarchy allow
background scenes to be overlaid and image editing to
occur.
 Keying makes only certain parts of a clip transparent
which can then be filled with other images (clips on the
lower tracks of the timeline.)
 Output may be to
videotape for display on a
television or to a digital
file for display through a
computer output device.
 Output may be put into
other presentation
programs such as
PowerPoint.
 Export goals will determine the output
settings that you choose.
 Does the production need to operate on
Windows and/or Mac platforms?
 What software will be used to play your
production?
 What image quality is required?
 How big can the file size be?
 Will the production be displayed on the
Web?
 Common digital outputs
 Audio Video Interleave (avi) – for use on Windows
only computers, good for short digital movies.
 QuickTime – a cross platform Apple format that is
popular for Web video.
 RealVideo – RealNetworks streaming video is an
extremely popular format.
 Video editing programs may be exported to other
multimedia programs (such as Macromedia Director or
Authorware) for addition editing or integration with
other materials such as Flash programs.
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