360-degree video is typically formatted in an equirectangular projection and is either monoscopic, with one image directed to both eyes, or stereoscopic, viewed as two distinct images directed individually to each eye for a 3D effect. Due to this projection and stitching, equirectangular video exhibits a lower quality in the middle of the image than at the top and bottom. Spherical videos are frequently in curvilinear perspective with a fisheye effect. The heavy barrel distortion often requires rectilinear correction before applications in detection, tracking or navigation.
In March 2015, YouTube launched support for publishing and viewing 360-degree videos, with playback on its website and its Android mobile apps. Parent company Google also announced that it would collaborate with camera manufacturers to make it easier for creators to upload 360-degree content recorded with their products to YouTube. However, in 2017, Google and YouTube began to promote an alternative stereoscopic video format known as VR180, which is limited to a 180-degree field of view, but is promoted as being more accessible to produce than 360-degree video, and allowing more depth to be maintained by not subjecting the video to equirectangular projection