How to manage 360 dual fisheye video directly on kdenlive

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Hello everybody.
After discovering i can use the equirectangular to equilinear vr filterer on kdenlive i was trying to speedup and increase teh quality of my 360 footage.

Original clips shooted by my lg360 or gopro360 max or samsung gear 360 are basically captured by 2 square sensors, trough a pair of fisheye lens and stamped on 2x1 frame, side by side.
In this example every sensor captures 1440x1440 and when paired they are 2880x1440.

how to rectilinear in kdenlive
how to rectilinear in kdenlive1220×459 369 KB

at the moment i have to “stitch” video outside kdenlive with various tools [every camera has is own solution, and i can list them if someone interested].

So i have to loose some quality in the:
A] “dual fisheye” → “equirectangular” external transcoding
B] use kdenlive filter for “equirectangular” to “rectilinear” the clip (suppose this is lossless)
C] encode the final product.

so the question is … could be possible to integrate in the VR effects section, a filter that makes [A pass] directly (and lossless for what is possible)?

By the way, for gear360 i stich it with a script like that:

#!/bin/bash

# Get the directory of the script
scriptpath=$(realpath $0)
dir=$(dirname $scriptpath)
cd $dir

# Find files matching the pattern "360*[0-9].MP4"
files=$(find . -maxdepth 1 -type f -name "360*[0-9].MP4" | sort)

# Get the first file in the list
firstFile=$(echo "$files" | head -n 1)

# Get the height of the video using ffprobe
height=$(ffprobe -v error -select_streams v:0 -show_entries stream=height -of default=nw=1 "$firstFile" | awk -F'=' '{print $2}')

# Output the height
echo $height

# Set the size based on the height
size="${height}x${height}"

# Output the size
echo $size

# Run ffmpeg command to process the video
ffmpeg -f lavfi -i nullsrc=size=$size -vf "format=gray8,geq='clip(128-128/6*(180-195/($height/2)*hypot(X-$height/2,Y-$height/2)),0,255)',v360=input=fisheye:output=e:ih_fov=195:iv_fov=195" -frames 1 -y mergeVmap.png

#!/bin/bash

for f in "$files"; do
    out=$(basename "$f")
    ffmpeg -hwaccel auto -i "$f" -i mergeVmap.png -f lavfi -i color=black:s=2x2 -lavfi "[0]format=rgb24,split[L][R];
    [L]crop=ih:iw/2:0:0,v360=input=fisheye:output=e:ih_fov=192.5:iv_fov=193.5[L_fov];
    [R]crop=ih:iw/2:iw/2:0,v360=fisheye:e:yaw=179:ih_fov=194:iv_fov=194[R_fov];
    [1]format=gbrp[fmt];[L_fov][R_fov][fmt]maskedmerge,overlay=shortest=1" -qp 13 -b:v 30M -b:a 192k -r 24 -y "V.${out}_STITCHED.MP4"
done

rm -f mergeVmap.png