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In the start of this video you will see "Salmon Raju" .. That is text that looks is staying still according to the location in the scene but the camera is still moving around.

I can understand simply watermarking movies, which I see during the start of movie when showing cast names etc, but I am curious how they do the first thing I asked.

If you have seen Indian Premier League matches you would have notices they many a times show a Player's score and Runs to Win and some other things in the middle of ground that is staying still but the camera is moving around the ground.

How do they do it?

I am a Software Engineer but unable to figure it out, any answers with technical/non-technical explanations are welcomed.

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    My best guess is something like Adobe After Effects, I've seen it done in movies too and I've wondered about this myself. – Johnny Bones Dec 5 '16 at 20:26
  • No No ... I have seen it in Live cricket matches too ... – Umair Dec 5 '16 at 20:28
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    I think its a simple transparent overlay which can be keyed to landmarks in the frame. e.g. at the start of the video, it will be tracking the buildings. in a live sports match, it will be keyed to markings on the pitch or around the arena. The expensive versions can even create a virtual mask so the text/image "disappears" behind things. – Tim Dec 5 '16 at 20:34
  • @Tim good pick ... in the live match that text must be tied to the pitch ... :P – Umair Dec 5 '16 at 20:37
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    @Tim That's a pretty accurate description of what happens. It's pretty much how they key any CGI to a moving frame. Pick reference points, tie the CGI to the same points and the software tracks it automatically. – Paulie_D Dec 5 '16 at 20:40
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This effect is usually referred to as 'motion tracking'. Motion tracking involves tracking certain points on objects within the original video and applying the movement of this tracking to a new object or piece of text added in post production. Objects can be tracked on all 3 axis with modern programs.

Adobe After Effects, as mentioned, is just one of a handful of these programs and is widely used throughout the film industry to accomplish such effects. Here's an example of just how quick it is to achieve.

At a basic level, motion tracking allows you to add 2D and 3D text to a scene. However, highly skilled animators and editing crew can use this fundamental technique to create complex virtual, (but realistic looking) scenes using other 3D software, 3DS Max coupled with Boujou for example. This is a video showing examples of tracking a real scene and adding in the virtual scene in post production.

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