app.R

In lizhongliu1996/melodyExtracter: This is a package that can remove the vocal part of a song that sings the melody, gives you only the accompaniment so that you can record and sing on karaoke or live

library(shiny)
library(shinyWidgets)
library(melodyExtracter)
options(shiny.maxRequestSize=60*1024^2)

ui <- fluidPage(

  setBackgroundImage(src = "https://images.wallpaperscraft.com/image/microphone_wire_sound_123334_1920x1080.jpg"),

  h1("This is a shiny webpage to get rid of vocal melody of a song"),
  p("Please upload the wav file you want to remove melody(please be patient for shiny.io server to response)"),
  p("Beware: this only applys to song with vocal pan = 0, add low freq compensation
    will strengthen"),
  p("the sound of frequency 70~100Hz,  which is the freq of bass and
    drum, but this might also "),
  p("add some vocal reverb and delay effects, also clicking sound"),
  p("if you want to do equalization to get better performance, please use this package in R"),

  # App title ----
  titlePanel("Uploading wav Files"),

  sidebarLayout(

    # Sidebar panel for inputs ----
    sidebarPanel(

      # Input: Select a file ----
      fileInput(
        inputId = "song",
        label = "Choose WAV File",
        multiple = FALSE,
        accept = c(".wav"),
        buttonLabel = "Browse...",
        placeholder = "No file selected"
      ), # end of input wav

      checkboxInput(
        inputId = "compensate",
        label = "Add low freq compensation",
        value = FALSE
      ) , # end compensate part

      sliderInput(
        inputId = "keyChange",
        label = "semitones you want to change",
        min = -12,
        max = +12,
        value = 0
       ),# end keychange part

      submitButton("confirm", icon("confirm"))

      ), #end of Sidebar panel

    # Main panel for downloading outputs ----
      mainPanel(
         tableOutput("contents"),

      # Output: Data file ----
         downloadButton(
            outputId = "downloadData",
            label = "Download"
         )#end of download

        )#end of mainpanel

  ) #end of sidebar layout
)# end of ui

  # Define server logic to read selected file ----
server <- function(input, output, session) {

      songLoad <- reactive({
         req(input$song)
         input$song
      })

      advanced <- reactive({
        input$compensate
      })

      key <- reactive({
        req(input$keyChange)
        input$keyChange
      })

      output$downloadData <- downloadHandler(
            filename = function() {
              paste("novocal-", Sys.Date(), ".wav", sep="")
            },
            content = function(file) {
              melodyExtractor(
                songLoadPath = as.character(songLoad()[4]),
                songSavePath = file,
                compensate = advanced(),
                keyChange = key()
              )
            }
      )

} # end of server

shinyApp(ui, server)