MainLogic.Rmd

```{r}
library(httr)
library(tidyverse)

end.point <- "https://westeurope.api.cognitive.microsoft.com/face/v1.0/detect"
key1 <- "Your key"

```
```{r}
base.dir <- "Directory of the main video, subtittle and python file"
file.name = "VideoName.mp4"
subtitle.name <- "Subtitle.srt"
cut.name <- "Cut.mp4"
```

```{r}

file.url = paste(base.dir, file.name, sep = "" )
bashFunction = paste("/usr/local/bin/mediainfo", file.url, sep = " ")

resultFromMediaInfo <- system(bashFunction, intern = TRUE)

#1 = General, 2 = Video, 3 = Audio
x <- grep("Duration",resultFromMediaInfo,value=T)

duration = sub("Duration *:", "", x[1])
min = strtoi(sub(" min .* s","",duration))
sec = strtoi(sub(" s", "", sub(" .+ min ","",duration)))
totalSec = min * 60 + sec

fps <- str_extract(grep("Frame rate",resultFromMediaInfo,value=T)[2],regex("(\\d*)(?=[.])"))


callsPerMinute = 20
timeInterval = totalSec / callsPerMinute
timeInterval = ceiling(timeInterval)

library(reticulate)
os <- import("cv2")
pythonparameters = paste0(file.url," ",timeInterval," ",fps)
pythonFunction = paste("python read_frames_fast.py ", pythonparameters, sep="")
system(pythonFunction, wait=TRUE)

```

```{r}
send.face <- function(filename){
  face_res <- POST(url = end.point,
                   add_headers(.headers = c("Ocp-Apim-Subscription-Key" = key1)),
                   body = upload_file(filename,"application/octet-stream"),
                   query = list(returnFaceAttributes = "emotion"),
                   accept_json()
                   )
  
  if(length(content(face_res)) > 0 )
  {
    ret.expr <- as_tibble(content(face_res)
          [[1]]$faceAttributes$emotion)
  } else {
    ret.expr <- tibble(contempt = NA,
                       disgust = NA,
                       fear = NA,
                       happiness = NA,
                       neutral = NA,
                       sadness = NA,
                       surprise = NA)
  }
  return(ret.expr)
}
```
```{r}

extract.from.frames <- function(directory.location)
{

  face.analysis <- dir(directory.location) %>%
    as_tibble() %>%
    mutate(filename = paste0(directory.location,"/",value )) %>%
    group_by(filename) %>%
    do(send.face(.$filename)) %>%
    ungroup %>%
    mutate(frame.num = str_extract(filename, regex("(\\d*)(?=[.])")))
  

  
  #Save temporary data frame for later use
  temp.filename <-tail(stringr::str_split(directory.location,
                                          stringr::fixed("/"))[[1]],1)
  
  write_excel_csv(x = face.analysis, path =
                    paste0(base.dir, temp.filename, ".csv"))
  return(face.analysis)
}


```
```{r}

frames.dir <- paste(base.dir, "frames", sep = "")
results.many.frames <- extract.from.frames(frames.dir)


```


```{r}
#Read Subtitle 
library(subtools)


lowestNeutralFrame = strtoi(results.many.frames$frame.num[order(results.many.frames$neutral)[1]])
summarizedDuration = 10
approxStartingTime = lowestNeutralFrame * timeInterval - summarizedDuration
approxFinishingTime = approxStartingTime + summarizedDuration

#Second to Hour:Minute:Second
convertSecond <- function(input, flag)
{
  if(flag == 0)
  { hour = floor(input / 3600)
    second = input - hour * 3600
    minute = floor(second / 60)
    second = second - minute * 60
    x = paste0(hour,":",minute,":",second)
  }
  else
  {
    x = input
  }
  
  object <- strptime(x,"%H:%M:%OS")
}

#To find Last Character
substrRight <- function(x, n){
  substr(x, nchar(x)-n+1, nchar(x))
}



subTitleDir <- paste0(base.dir,subtitle.name)

subtitleDF <- read.subtitles(subTitleDir)

approxStartingTime <- convertSecond(approxStartingTime,0)
approxFinishingTime <- convertSecond(approxFinishingTime,0)

subtitleStartTimes <- convertSecond(subtitleDF[["subtitles"]][["Timecode.in"]],1)
subtitleFinishTimes <- convertSecond(subtitleDF[["subtitles"]][["Timecode.out"]],1)

summaryStartingTime = subtitleDF[["subtitles"]][["Timecode.in"]][which(abs( subtitleStartTimes - approxStartingTime ) == min(abs( subtitleStartTimes - approxStartingTime ) ))]

summaryFinishTimeIds <- which( (subtitleFinishTimes - approxFinishingTime > 0) )

summaryFinishTime <- subtitleDF[["subtitles"]][["Timecode.out"]][summaryFinishTimeIds[min(which( substrRight(subtitleDF[["subtitles"]][["Text"]][(summaryFinishTimeIds)],1) == "."))]]




```

```{r}
summarizedDuration = convertSecond(summaryFinishTime,1) -  convertSecond(summaryStartingTime,1)

#ffmpeg to cut the video a section
#ffmpeg -i movie.mp4 -ss 00:00:03 -t 00:00:08 -async 1 cut.mp4
system(
     paste0(
      "ffmpeg -i ", file.url,
      " -ss ", summaryStartingTime,
      " -t ", summarizedDuration,
      " -async 1 ", cut.name)
    )
```