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Secret Garden Party

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Here are some clips from the Secret Garden Party 2006 - they are 384x288 mjpeg avi - you can get higher resolution quicktime version from archive.org

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Design Of Signage

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A selection of VJing clips made from public domain signs. The original designs were produced by Ravi Poovaiah, Professor, IDC, IIT Bombay.

768x576 Pic Video MJPEG codec avi files - visit the archive.org page for quicktimes
arrowspin

PIXnMIX

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Here are the clips i made for the PIXnMIX project - they are on the Creative Commons Attribution-NonCommercial-ShareAlike licence (explanation of which is here the MOVs are the same clips as the avi please only download the MOVs if you can't use the indeo 5.1 avi files. AVI Files (indeo 5.1 384x288 25 FPS)
0-9matrix10bt 1-4tvmash16bt bluesmokey CNNscrambled dancingwoman16bt monitors16bt redheartbeats4bt ? ? ? ? ? ? ? ? signs37bt

Aspect Ratio pt2 (widescreen content)

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In the first part of this series we looked at standard 4:3 content and saw how the relationship between pixel aspect ratio and dimensions go together to define the shape of the frame. In this article we will look at widescreen content and examine a range of methods for producing and displaying widescreen content.

Widescreen content is becoming more and more popular, not only in cinema and broadcast production but in live event video too. There are many different aspect ratios in use across these disciplines which makes things more complex than perhaps they need be. For the sake of simplicity we will look only at 16:9 widescreen as this is the most popular of the wide aspect ratios and is the ratio that the majority of plasma and LCD screens are available in.

16:9 content comes in three basic flavors

  • Letterbox
  • Anamorphic
  • True 16:9

Letterbox content is normal 4:3 video which has black bars rendered across the top and bottom to mask off the central 16:9 display area. PAL video of this type has a frame size of 768x576 or 720x576, however the active video area is considerably lower resolution due to so much of the frame being masked off.

Letterboxed widescreen has the advantage that it can be displayed on regular 4:3 displays and mixed with normal vision mixers - all playback systems can deal with letter boxed widescreen as it is effectively the same as 4:3 content.

The majority of 16:9 displays (eg plasma and LCD screens) can be set to correctly crop the black bars from the top and bottom of the content so the display shows the active content area full screen

Aspect Ratio (non-widescreen content)

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Aspect ratio is important - it defines what shape you video will be. if you display things at the wrong aspect ratio your video will be distorted.
Video comes in many different formats - for the purposes of this document we'll stick to looking at PAL video - we will look video that originates from DV cameras and video that is entirely created on computer.
Digital video's aspect ratio is controlled by two basic factors, the pixel dimensions of the frame and the aspect ratio of the pixels.
  • Standard non-widescreen video has an aspect ratio of 4:3
  • PAL Video is 768x576 square pixels
  • PAL DV Video is 720x576 D1 Pixels
  • D1 Pixels are rectangular they have an aspect ratio of 1.066:1
  • Square Pixels have an aspect ratio of 1:1
Square Pixels (1:1) D1 Pixels (1.066:1) Overlay on one another its easier to see
Square pixels are square D1 pixels are rectangular Overlayed on each other its easy to see the different shapes
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© Tom Bassford 2005-2006