This footage was taken while the Romanov family was visiting Romania in 1914. In the foreground we see Grand Duchess Anastasia Nikolaevna bouncing up and down in a silly way. One might wonder why she is doing this. To find out we have to analyze this piece of rare footage.
Anastasia seems to be talking to someone in a white dress and a hat on. That person is who i believe to be Princess Marie “Mignon” of Romania (later Queen of Serbia). In the background of this footage we also see Queen Elisabeth of Romania (far right with baby Prince Mircea of Romania being held by someone), Tsar Nicholas II, Tsarina Alexandra Feodorovna, and Grand Duchess Maria Nikolaevna (talking with people), and Grand Duchess Tatiana Nikolaevna who we see towards the end of the clip holding what looks like a Brownie Box Camera which the Romanov family used to take pictures.
Now what are Anastasia and Mignon doing? My belief is that Mignon went to greet Anastasia by naturally curtsying (which was the correct protocol) and Anastasia also did the same thing at the same time. I think Anastasia was doing several small curtsies afterward to kind of make a joke out of the moment (hence the giddy bouncing we see in the footage). OTMAA always felt embarrassed or shocked when close members of their family, or anyone at all, treated them with their normal official rules that the protocol demanded (aka curtsying or using official titles). Anastasia probably wanted to break the ice in that moment or make a funny joke of the curtsying at the same time thing. Also we can see the two girls having a good laugh so that could also be why Anastasia is bouncing so much.
In the end of the footage we see Tatiana come up to the two girls with her camera ready and it looks like she is going to take a picture of them. The following photo could be the one she took but I’m not sure that it is.
Here are some other photos from the day that this footage was taken: