Introduction - 3DTV: Processing and Transmission of 3D Video Signals - page 23

Figure 1.7 Example of frame compatible stereoscopic video, with the left
and right frames packed into sequential frames

Service compatible stereoscopic video will be used in the second generation
of 3DTV broadcasts, and has been specified for use in the 3D Blu-Ray
standard. This format removes the limitations of frame compatible video by
presenting the frames separately, as shown in Figure 1.7. Full High Definition
resolution can therefore be achieved with this format. Its disadvantage is
that it requires changes to the system used to transport the video, requiring
users to be supplied with new set-top boxes or disc players.

1.2.2 Colour-Plus-Depth

Depth maps (also known as range images) have been of considerable interest
to 3D video researchers in recent years. Depth map sequences usually have
similar spatio-temporal resolution as the colour image sequence with which
they are associated. The depth maps can be stored as 8-bit per pixel grey
values, where grey value 0 specifies the furthest position from the camera,
and a grey level of 255 specifies the closest position to the camera. This
depth map representation can be mapped to real, metric depth values. To
support this, the grey levels are normalized into two main depth clipping
plains. The near clipping plane Z near (grey level 255), represents the smallest
metric depth value Z . The far clipping plane Z far (grey level 0), represents
the largest metric depth value Z . In case of linear quantization of depth, the
intermediate depth values can be calculated using the following equation:

v Z near −

with v

Z far

=

Z far +

∈ ...

Z [0, , 255] (1.1)

255

where v specifies the respective grey level value.
An example colour-plus-depth representation can be seen in Fig. 1.8.