The method in the video looks elegant, except that the shadow plane remains visible when composited over a video image. I ended up doing something similar based on
viewtopic.php?f=22&t=56315, with an extra step of compositing a tree in the foreground to pass in front of the 3D text. (The foreground tree does not appear in this frame.)
The only problem with this is that I can't control the darkness of the shadow on the ground, so if you look between the "d" and the "T" in the attached image, you'll see the pedestrians are casting a shadow on top of the composited shadow. Adding a ColorCorrector node after Merge5 lets me darken the shadows from the 3D text, but it makes the overlapped shadow darker as well.
I'm also puzzled by the jagged edges on the shadows. Any idea what's causing that?
Resolve Studio 18.6.6 (build 7); iMac 27 inch, Retina 5K; 4.2 GHz Quad-Core Intel Core i7 processor; 64 GB 2400 MHz DDR4; Internal 2TB SSD; Radeon Pro 580 8 GB graphics running Ventura 13.6.4.