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A NEW MEDIUM

Wonder what a 360° video is?

In this page we describe what it is and what is involved in the production of a 360° video.

Traditional VS 360° camera

Traditional VS 360° camera

Cameras, as we know them up till now, are characterized by a front, a back, a field of view and they describe a portion of what happened in front of them giving the spectator a point of view. The director decides what to show and what not to show to his/her viewers. Essentially when we watch a video we hear a story.

A 360 camera is a new type of camera that has no front, no back, no left and no right. It records everything that happens around it and gives the spectator a point of presence. The viewer is immersed into the scene and it is him/her to decide where to look. When we watch a 360 video we live the scene.

How does it work?

How does it work?

A 360 camera can be built in various ways but it is essentially composed by an array of traditional cameras that work together to achieve a spherical image. The number of cameras varies a lot going from 2 to 16: sometimes you may prefer a smaller and more portable camera, sometimes you need a bigger camera with higher quality. Each camera captures a portion of what is happening around it and all together they are able to capture everything that a viewer could see if it were where the camera was standing.
The stitching phase

The stitching phase

The output of a 360 camera are a bunch of videos: one from each camera that composes the 360 array. To transform them into a spherical video you need to go through the stitching phase, one of the hardest part of the workflow.

In this phase you need to pick a frame from each camera and join them into a single merged one. This process must be repeated for every frame that composes the video. The difficulty in doing this is that the human eye is very capable in detecting anomalies and errors and they are felt as unnatural.

Equirectangular projection

Equirectangular projection

Once you have the spherical image you need a way to represent it. How to draw the surface of a sphere on a two dimentional plane is a long dated task that man solved many centuries ago. Mercator, in the 16th century, invented his famous projection that we still use today to draw the surface of the earth on two dimentional maps.

Unwrapping the surface of a sphere on a plane is an impossible task and some distortion must occur: things near the equator maintain their proportions while things near the poles get more and more distorted.

For 360 videos we use a similar approach and we use a projection called equirectangular. In this way we can treat a 360 video almost as if it were a standard 2D video.

The player

The player

Watching a spherical video in equirectangular projection is not very exciting: to watch it in the proper way we need a dedicated player that understands the equirectangular format and provides extra controls. We can use a variety of devices to watch a 360 video:

  • a PC with a web browser
  • our smartphone or tablet
  • a virtual reality headset
The viewer decides where to look

The viewer decides where to look

The player must transform the spherical image into something closer to human sight. Since we have a spherical image that represents what happened around the camera the idea is to place the viewer right where the camera was: in the center of the sphere. The viewer can now look around and see how the sphere looks like, seeing a portion of the scene at a time as if it was where the camera was standing at the moment of shooting.

If the viewer does not move from his/her position the illusion is perfect.

The way in which the viewer controls where to look depends on the device used.

Web player

Web player

The web player is the less natural way to watch a 360 video but who does not have a PC with a web browser?! The viewer watching a 360 video sees a portion of the spherical image on the monitor as if he/she were controlling a virtual camera inside the scene. By clicking and dragging you can move the virtual camera and see different portions of the scene. Some players also allow zooming in and out through mouse scroll.
Smartphones and tablets

Smartphones and tablets

Mobile devices benefited a stunning evolution in the latest years. With fast processors, high resolution displays and a full set of on board sensors they are a great way to watch a 360 video. Thanks to accelerometers, gyroscopes and some magic, the device knows where you are pointing at: you can point the device somewhere and use it as if it were a window into the scene, a sort of worm hole that leads to another place and another time in the universe. Definitely a powerful tool in your hand.
Virtual reality headsets

Virtual reality headsets

This is the most immersive, natural and powerful way to watch a 360 video. A virtual reality headset substitutes human vision completely and the viewer is teleported into the scene. As you rotate your head the device understands where you are looking and it shows what you would see in that situation. You lose contact with reality and feel like you are there. Another big plus of headsets is that they can show 360 stereoscopic (3D) videos.