VideoComparison: Calculate the matching segment between two video motion...
In VideoComparison: Video Comparison Tool

Description Usage Arguments Details Value Author(s) References Examples

For two video segments represented by their own video motion vector it is interesting to look for their matching in order to verify potential coherence between them happens.

The video motion curves can be derived from the opensource tool called shotdetect http://johmathe.name/shotdetect.html.

By using an improved algorithm based on the Cui et al paper it is implemented the identification of which segment bigger than the requested length, is common to both videos, in terms of motion structure.

1	VideoComparison(mm,m2,stp,nprocesses=0)

`mm`	Motion vector for video 1. It is supposed to be contained in the second one so, it will be shorter than the second vector
`m2`	Motion vector for video 2. It is supposed to be the container
`stp`	Unit of motion curvature to be considered as relevant for our analysis.
`nprocesses`	Number of processes that should be spawned. If 0, it's left to the function's discretion. Requires package parallel to spawn more than 1 process.

This function maximizes the score (Score of matching = length of matching * degree of matching), but returns it separated by its components.

If the package parallel is available, this function will run across several processes.

The output provided is a list with following components:

`$sc`	Degree of matching
`$pos1`	Frame where matching starts in video1
`$pos2`	Frame where matching starts in video2
`$lngth`	Length of matching segment found

Silvia Esinosa, <silviaespinosag@gmail.com>, Jose Maria Perez, <josem.perez.ramos@gmail.com>, Joaquin Ordieres, <j.ordieres@upm.es>, Antonio Bello, <abello@uniovi.es>.

Espinosa-Gutiez, S., Ordieres-Mere, J., Bello-Garcia, A.: Large scale part-to-part video matching by a likelihood function using featured based video representation. TAMIDA 2013 - Taller de Mineria de Datos dentro del IV congreso Espannol de Informatica. 254-257 (2013). http://bioinspired.dacya.ucm.es/maeb2013/images/ActasCAEPIA_final.pdf
Cui, M., Femiani, J., Hu, J., Wonka, P., Razdan, A.: Curve matching for open 2D curves. Pattern Recogn. Lett. 30, 1-10 (2009)

#load example json from data folder
fileName1 = strcat(path.package(package="VideoComparison"),"/extdata/videomotion1.gz")
json1 = readLines(gzfile(fileName1))
fileName2 = strcat(path.package(package="VideoComparison"),"/extdata/videomotion2.gz")
json2 = readLines(gzfile(fileName2))

#Extract data from json
hh<- as.numeric(unlist(lapply(fromJSON(json1)$hits$hits[[1]]$`_source`$video_hash$frames,head,1)))
h2<- as.numeric(unlist(lapply(fromJSON(json2)$hits$hits[[1]]$`_source`$video_hash$frames,head,1)))

## Requires specific server architecture
# hh<-ExtractMotion("C0031D0")
# h2<-ExtractMotion("C0035D0")

mm<-VideoComparison(hh,h2,12,nprocesses=1);