Loads the FER-2013 dataset for facial expression recognition. The dataset contains grayscale images (48x48) of human faces, each labeled with one of seven emotion categories: "Angry", "Disgust", "Fear", "Happy", "Sad", "Surprise", and "Neutral".

fer_dataset(
  root = tempdir(),
  train = TRUE,
  transform = NULL,
  target_transform = NULL,
  download = FALSE
)

Arguments

root

(string, optional): Root directory for dataset storage, the dataset will be stored under root/fer2013.

train

Logical. If TRUE, use the training set; otherwise, use the test set. Not applicable to all datasets.

transform

Optional. A function that takes an image and returns a transformed version (e.g., normalization, cropping).

target_transform

Optional. A function that transforms the label.

download

Logical. If TRUE, downloads the dataset to root/. If the dataset is already present, download is skipped.

Value

A torch dataset of class fer_dataset. Each element is a named list:

  • x: a 48x48 grayscale array

  • y: an integer from 1 to 7 indicating the class index

Details

The dataset is split into:

  • "Train": training images labeled as "Training" in the original CSV.

  • "Test": includes both "PublicTest" and "PrivateTest" entries.

Examples

if (FALSE) { # \dontrun{
fer <- fer_dataset(train = TRUE, download = TRUE)
first_item <- fer[1]
first_item$x  # 48x48 grayscale array
first_item$y  # 4
fer$classes[first_item$y]  # "Happy"
} # }