# VR360 Hemispherical to Equirectangular¶

Description

This effect/filter converts a video frame with two hemispherical images to a single equirectangular frame.

The plugin assumes that both hemispheres are in the frame. If you have a camera like the Garmin Virb360 that produces two videos, one from each camera, you should start by converting them to a single movie by placing them side by side using, for example, ffmpeg (you can also add parameters to produce lossless, intra-only output here for easier editing):

```
ffmpeg \
-i left.mp4 \
-i right.mp4 \
-filter_complex hstack \
output.mp4
```

Parameters

Parameter |
Value |
Description |
---|---|---|

Projection |
Selection |
The fisheye projection type |

Interpolation |
Selection |
Determines the sampling method |

Alignment Yaw / Pitch / Roll |
Integer |
Adjust the rotation along the Z- (yaw), X- (pitch) and Y-axis (roll) to compensate for any alignment differences |

Lens FOV |
Integer |
Field of View of a single hemisphere in degrees |

Lens Radius |
Float |
Radius of the image circle as a fraction of the frame width (for example 0.25 = 25% of 1920) |

Front X / Y |
Float |
Defines the center of the image of the front-facing camera. X is expressed as a fraction of the image width, Y as a fraction of the image height. |

Front UP |
Integer |
Defines the “up” direction in the image in degrees counting clockwise from a directions towards the top edge |

Back X / Y |
Float |
Defines the center of the image of the back-facing camera. X is expressed as a fraction of the image width, Y as a fraction of the image height. |

Back UP |
Integer |
Defines the “up” direction in the image in degrees counting clockwise from a directions towards the top edge |

Nadir Radius / Start |
Float |
Adjust the nadir of the camera if you have parts of the camera or equipment in the image |

The following selection items are available:

Projection

Equidistant Fisheye |
default |

Interpolation

Nearest-Neighbor |
default |

Bilinear |