Intelligent Moviemaking-Enrich Video Content with Media Objects Working ReportCOMP3419 Multimedia Assignment (Option-1) Semester 1,2012

Weilong Ding309056942

Story Plots

The title of the short video is called Sheep Run. In the 30-sec video a red car was carrying a sheep and suddenly the sheep fell off from the car and started running around. The car tried to get the sheep back but after it hit two trees down, it gave up keeping chasing this annoying sheep.

Technical details

In the project JMF Library is used to process the video. To modify the video clip, each frame of the video is accessed to do the modifications. There are some key technical points needs mentioning:

1. Adding background2. Controlling running sheep3. Controlling tree

To add a new background to replace the blue screen in the original video clip, I set two thresholds for Red value and Blue value of the RGB value of a pixel respectively. Since what we want is just the red car, two thresholds can make the resultant image more precise. The Red Threshold is for getting the red car and the Blue threshold can remove some noise. If the RGB value of a pixel meets the condition, we replace the pixel with the same coordinates in background image with the desired one and finally a perfect red car is “cropped out” from the original image and composited with the background image.

One important function we want to achieve in the project is to allow the movement of the red car influence the movement of sheep. Firstly since we want the red car to carry the sheep at the beginning, we need to decide the location of the red car and this is done while we are cropping out the red car. Since in the original image the red car is really easy to be identified and there are barely noises, to get the location of the red car we need to get the highest point, lowest

point, leftmost point and rightmost point. By doing this, we can get the “origin point” of the red car pretty straight-forward: originX = (leftmostX+rightmostX)/2, origin = (highestY+lowestY)/2. When we are modifying a certain frame, we crop the red car and get the location of the red car so that the sheep can follow the red car.

In the later part of the video clip although the sheep also need to do some actions according to the frame, its movement is also influenced by the location of the red car so that an effect that the car is chasing the sheep can be achieved.

In the video clip the sheep can jump, which is done by using sin function with trivial modification on the parameters.

In the video the two trees will fall down if the car “hit” them. The falling movement is also achieve by using AffineTransform provided by JAVA API because we can just simply rotate the trees to show the falling effect. The frame number also influences the falling movement of the tree so that the movement can be animated.