rm(list=ls())
library("png")
library("grid")


# Set the file
# frisbee
filename <- "./VID_20240503_045652.mp4"
# Start in seconds
tstart <- 2
# End
tend <- 4
# Number of frames
nframes <- 10

## ----------------------------------------------------------------
## Extract the images from the video
unlink("tmp", recursive = TRUE)
dir.create("tmp")
# Get the number of frames
val <- system(paste0("ffprobe -select_streams v -show_streams ",filename), intern=TRUE)
n <- as.integer(gsub("nb_frames=", "", val[grep("nb_frames=", val)]))
duration <- as.numeric(gsub("duration=", "", val[grep("duration=", val)]))
# check
if(tend > duration){ stop("tend=",tend," higher than duration=",duration) }
# start and end in frames
istart <- floor(n * tstart/duration)
iend <- ceiling(n * tend/duration)
iseq <- floor(seq(istart, iend, len=nframes))
# Extract the frames and keep in list
L <- list()
for(i in 1:length(iseq) ){
  system(paste0("ffmpeg -i ",filename," -vf 'select=eq(n\\,",iseq[i],")' -vframes 1 tmp/",i,".png"))
  L[[i]] <- readPNG(paste0("tmp/",i,".png"))
}
saveRDS(L,"tmpL.RDS")
## ----------------------------------------------------------------

## ----------------------------------------------------------------
## Register the positions
D <- matrix(0,nrow=length(iseq),ncol=2)
colnames(D) <- c("x","y")
##
par(mar=c(0,0,0,0), mai=c(0,0,0,0), oma=c(0,0,0,0), xaxs='i', yaxs='i')
plot.new()
rasterImage(L[[1]],0,0,1,1)
for(i in 1:length(iseq)){
  rasterImage(L[[i]],0,0,1,1)
  tmp <- grid.locator("npc")
  D[i, ] <- unlist(tmp)
}
graphics.off()
saveRDS(D, "tmpD.RDS")
## ----------------------------------------------------------------


## ----------------------------------------------------------------
## Upload
## ----------------------------------------------------------------
system("scp tmpD.RDS pbac@thinlinc.compute.dtu.dk:~/www/")
system("scp tmpL.RDS pbac@thinlinc.compute.dtu.dk:~/www/")