This article introduces the ISO/IEC MPEG Immersive Video (MIV) standard, MPEG-I Part 12, which is undergoing standardization. The draft MIV standard provides support for viewing immersive volumetric content captured by multiple cameras with six degrees of freedom (6DoF) within a viewing space that is determined by the camera arrangement in the capture rig. The bitstream format and decoding processes of the draft specification along with aspects of the Test Model for Immersive Video (TMIV) reference software encoder, decoder, and renderer are described. The use cases, test conditions, quality assessment methods, and experimental results are provided. In the TMIV, multiple texture and geometry views are coded as atlases of patches using a legacy 2-D video codec, while optimizing for bitrate, pixel rate, and quality. The design of the bitstream format and decoder is based on the visual volumetric video-based coding (V3C) and video-based point cloud compression (V-PCC) standard, MPEG-I Part 5.

Immersive videos allow users to freely explore 4 π steradian scenes within head-mounted displays (HMD), leading to a strong feeling of immersion. However users may miss important elements of the narrative if not facing them. Hence, we propose four visual effects to guide the user's attention. After an informal pilot study, two of the most efficient effects were evaluated through a user study. Results show that our approach has potential but it remains challenging to implicitly drive the user's attention outside of the field of view.