VR360 Hemispherical to Equirectangular

effects-vr360_hemi2equi-2504.webp

Descrizione

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

Parametri

Parametro

Valore

Descrizione

Proiezione

Selezione

The fisheye projection type. Currently only equidistant fisheyes, like the Ricoh Theta and Garmin Virb360 are supported.

Use sensor response parameters

Switch

Switch on to use sensor response parameters (see EMoR h(x) parameters below)

Interpolazione

Selezione

Determines the sampling method

Alignment Yaw / Pitch / Roll

Intero

Adjust the rotation along the Z- (yaw), X- (pitch) and Y-axis (roll) to compensate for any alignment differences

Lens FOV

Intero

Field of View of a single hemisphere in degrees

Lens Radius

Virgola mobile

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

Front X / Y

Virgola mobile

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

Intero

Defines the «up» direction in the image in degrees counting clockwise from a directions towards the top edge

Back X / Y

Virgola mobile

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

Intero

Defines the «up» direction in the image in degrees counting clockwise from a directions towards the top edge

Nadir Radius / Start

Virgola mobile

Adjust the nadir of the camera if you have parts of the camera or equipment in the image

Lens distortion A / B / C

Virgola mobile

Lens distortion correction parameters. The first three parameters are the same as in Hugin.

Lens distortion radius

Virgola mobile

Lens distortion correction parameters. If you use Hugin parameters, the Radius should be set to the value of (0.5 * min(image width, image height) / image width). For a 2:1 aspect dual hemispherical image, that would be 0.25.

Lens vignetting A / B / C / D

Virgola mobile

Lens vignetting correction parameters. The first four parameters are the same as in Hugin, corresponding to the Va , Vb , Vc , and Vd image parameters.

Lens vignetting radius

Virgola mobile

If you use Hugin parameters, the radius should be set to the value of (0.5 * image diagonal / image width). For a 2:1 aspect dual hemispherical image, that would be 0.5590. Use the A parameter to scale the effect and avoid overexposing highlights.

EMoR h(1 / 2 / 3 / 4 / 5)

Virgola mobile

Sensor response parameters. The EMoR h(x) parameters are the same as Hugin”s Ra - Re in the lens parameters. If you use Hugin-derived values for vignetting correction, you should also use these parameters, as Hugin”s vignetting correction assumes that the sensor response has been corrected.

Sono disponibili le seguenti voci di selezione:

Projection

Equidistant Fisheye

predefinito

Interpolazione

Più vicino

predefinito

Bilineare