1. Tech Report
Framerate, Video Format, Screen
Ratio, Resolution, and compression

2. Frame Rate
 The framerate of a video is the amount of frames (individual still
images) in each second of movement, and is consequently measured in
fps (frames per second). There are many different framerates used in
film, television and cinema, and all have their own advantages and
disadvantages though any framerate above roughly15 fps will be
recognised as movement , not still images, by the brain.
 24fps – The original framerate of 35mm film cameras and optical
projectors, and also the standard framerate of hand-drawn animation.
Produces fluid movement with very little noticeable judder.
 25fps – Similar results and quality to 24fps, but worth mentioning as
it is the standard framerate for PAL television.
 30fps – Used similarly to 24fps in film, but with less noticable
judder.
 50/60fps – Produces negligible judder, mostly found in HD formats.
 1000-10,000fps – The standard for slow motion. The higher the
framerate, the more frames in the film, therefore playing back at
lower framerates produces slower video.
 1,000,000,000,000 fps – A trillion frames per second. Never used for
commercial applications, but recently achieved by scientists at MIT to
study the movement of light.

3. Video Format
 Format refers to the way that digital video is stored and interpreted
by a computer. Different formats accomplish different tasks better and
can be interpreted and manipulated more easily on different systems.
Formats are distinguished by a file extension such .gif or .mkv.
 Some common video and audio formats include:
 .mp3 - The standard format for audio, widely recognised by nearly all
systems and software.
 .mp4 – The standard video format for the internet: is recognised by
Youtube, Flash and HTML5.
 .avi – A format developed by Microsoft that runs on all Windows
sofware and is common online.
 .mov/Quicktime – Similar to .avi, but developed my Apple for the Mac
system.
 .swf/.flv/Flash – Built for the internet by Macromedia and
subsequently taken over by Adobe. Has wide support on almost all
platforms.

4. Screen Ratio
 The screen ratio of a film or video refers to the width and
height of the moving image, and their relation to one another.
Different screen or aspect ratios will result in differently
sized and shaped images. Much like framerate and format, there
are a variety of different aspect ratios with different
uses, advantages and disadvantages. The two standard and most
common commercial aspect ratios used are 4:3 and 16:9.
Scaled
for clarity
 Some other less common aspect ratios include:
 3:2 – The aspect ratio of 35mm film, usually the standard film
stock for feature production.
 2.39:1/2.40:1 – The aspect ratio found in widescreen cinema.
Cinema
35mm Film
Widescreen

5. Resolution
 Similar in some ways to aspect ratio, the resolution of a video
describes its size: the higher the resolution the more pixels in the
image, and the higher the pixel count, the better the quality of the
image.
 Some common resolutions include:
 480i – Standard for NTSC standard-definition television (North
America)
 576i – Standard for PAL standard-definition television (Europe and GB)
 720p - 1280 x 720 pixels , standard resolution for high definition
video in many different formats. Aspect ratio is 16:9.
 1080p- 1920 x 1080 pixels, standard resolution for high definition
video in many different formats. Aspect ratio is also 16:9.
A chart showing many
different resolutions and
their relevant sizes.

6. Compression
 Compression refers to the act of eliminating large chunks of data from
a video or image to decrease its digital ‘size’ while still
retaining as much visual information as possible to reserve quality.
 Typically video is compressed by comparing groups of pixels(grouped my
colour, size and shape) from frame to frame retaining the information
only of those areas that change from one frame to the next. In moments
of very little change, action or movement the effect of eliminating
this information is negligible, though may lead to disfiguring
artefacts on the image. However, the effects of compression become
most notable in scenes where there is a lot of change between frames,
such as in a high-action sequence involving fast camera movements,
flames or explosions. At this point the quality of the image degrades
very quickly and causes the image to contain very noticeable artefacts
and aberrant pixels.
Three images exhibiting the
effects of compression on a
.jpg image that relies on
lossy compression to
reduce filesize.