https://github.com/javierluraschi/pixels

Tools for Working with Pixels in R
https://github.com/javierluraschi/pixels

Last synced: about 1 month ago
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Tools for Working with Pixels in R

• Host: GitHub
• URL: https://github.com/javierluraschi/pixels
• Owner: javierluraschi
• License: other
• Created: 2017-10-20T00:57:43.000Z (about 7 years ago)
• Default Branch: master
• Last Pushed: 2020-12-03T21:56:16.000Z (about 4 years ago)
• Last Synced: 2023-11-20T16:20:33.662Z (about 1 year ago)
• Language: R
• Homepage:
• Size: 488 KB
• Stars: 30
• Watchers: 4
• Forks: 2
• Open Issues: 6
• Metadata Files:
  • Readme: README.Rmd
  • License: LICENSE

Awesome Lists containing this project

• awesome-shiny-extensions - pixels - HTML widget and Shiny Gadget to render and draw pixels. (UI Components / Image / Audio / Video)

README

        
---

title: "Tools for Working with Pixels in R"

output:

  github_document:

    fig_width: 9

    fig_height: 5

---

[![CRAN_Status_Badge](https://www.r-pkg.org/badges/version/pixels)](https://cran.r-project.org/package=pixels)

This package provides an [htmlwidget](http://www.htmlwidgets.org/) and [Shiny Gadget](https://shiny.rstudio.com/articles/gadgets.html) to render and draw

pixels with ease.

To draw pixels run `get_pixels()` which will start the gadget to 

retrieve an array of numeric values representing each pixel in the image:

```{r eval=FALSE}

library(pixels)

get_pixels()

```



To display pixels, use `show_pixels()` with a row-first vector as

follows:

```{r eval=FALSE}

show_pixels(

  round(runif(400, 0, 1)),

  grid = c(40, 10),

  size = c(800, 200),

  params = list(fill = list(color = "#FF3388"))

)

```



Finally, one can use 'shiny_render_pixels()' with a 'Shiny' application to help

collect image datasets. For instance, to collect images similar to the MNIST

dataset as follows:

```{r eval=FALSE}

library(shiny)

ui <- fluidPage(

  tags$head(

    tags$style(HTML("

      #pixels {

        height: 270px !important;

        margin-top: 10px;

      }

    "))

  ),

  titlePanel("Digit Capture Application"),

  textOutput("prompt"),

  shiny_pixels_output("pixels"),

  actionButton("captureDigit", "Capture")

)

server <- function(input, output) {

  output$pixels <- shiny_render_pixels(

    show_pixels()

  )

  

  digit <- reactiveVal(floor(runif(1, 1, 10)))

  output$prompt <- renderText(paste0("Please draw number ", digit(), ":"))

  

  observeEvent(input$captureDigit, {

    digit_path <- file.path("digits", digit())

    if (!dir.exists(digit_path)) dir.create(digit_path, recursive = TRUE)

    saveRDS(input$pixels, paste0(digit_path, "/", as.numeric(Sys.time()), ".rds"))

    

    digit(floor(runif(1, 1, 10)))

    output$pixels <- shiny_render_pixels(

      show_pixels()

    )

  })

}

shinyApp(ui = ui, server = server)

```