C.4 3D Video Disparity Range Descriptor Scheme

26.2473GPPProgressive Download and Dynamic Adaptive Streaming over HTTP (3GP-DASH)Release 17Transparent end-to-end Packet-switched Streaming Service (PSS)TS

The 3D Video Disparity Range description scheme may only be signalled in SupplementalProperty element with SupplementalProperty@schemeIdUri set to urn:3GPP:dash:3dVideoDisparityRange:2013. When present the 3D Video Disparity Range description scheme shall be on the Adaptation Set level. The SupplementalProperty@value of 3D Video Disparity Range description scheme shall be present and is defined below using ABNF [40]:

@value="disparityRange"

disparityRange = disparityMinValue disparityMaxValue

disparityMinValue = [%x2D]1*3DIGIT

disparityMaxValue = [%x2D]1*3DIGIT

disparityMinValue and disparityMaxValue are expressed as the minimum and the maximum disparity, in units of pixels, divided by the width of the 3D video content, in units of pixels, multiplied by one hundred. disparityMinValue and disparityMaxValue shall be the same for all Representations included in an Adaptation Set containing this descriptor scheme.

NOTE 1: The disparity is the difference between the horizontal positions of a pixel representing the same point in space in the right and left views of a stereoscopic 3D video frame. Positive disparity values move the object away from the viewer whilst negative values move it towards the viewer. A value of zero places the object in the plane of the display screen.

NOTE 2: The DASH client can calculate the perceived depth of the stereoscopic 3D content based on the provided disparity range and the prevailing contextual information, such as a screen size used to display the content, and the calculated or predefined distance of a viewer from the display. Based on the calculated depth range perceived by a user, the DASH client can determine applicability of the stereoscopic 3D video content provided for a given Adaptation Set. [41]