Deutsch: Zimmer gerade fotografiert und in die abstandstreue Projektion umgerechnet.
${\displaystyle \varphi }$, ${\displaystyle \theta }$ sind Kugelkoordinaten (Objekt) und ${\displaystyle r}$, ${\displaystyle \phi }$ Polarkoordinaten (Bild).

English: Photo of room straightly taken and remapped into equidistant projection.
${\displaystyle \varphi }$, ${\displaystyle \theta }$ are spherical coordinates (object) and ${\displaystyle r}$, ${\displaystyle \phi }$ polar coordinates (image).

${\displaystyle r=f\cdot \theta }$
${\displaystyle \phi =\varphi }$

f = 1222.3 pixel

You can crop lossless with JPEGTRAN or JPEGCROP. The parameter format is WIDTHxHEIGHT+LEFT+TOP.