ct_read_metadata: Read Image Metadata

In ct: Camera Trap Data Management and Multi-Method Ecological Analysis

Read Image Metadata

Description

Extracts metadata from image files using ExifTool and returns the results as a tibble.

Usage

ct_read_metadata(
  path,
  tags = NULL,
  recursive = FALSE,
  parse_hs = FALSE,
  args = NULL,
  exiftool_path = NULL
)

Arguments

path	Character vector of image file paths or a directory path.
tags	Character vector of tag names to extract. Use: NULL or "all" to extract all tags "standard" to extract a predefined, commonly used set of tags a character vector of tag names to extract specific fields
recursive	Logical. If TRUE, searches directories recursively. Default is FALSE.
parse_hs	Logical. If TRUE, parses the HierarchicalSubject field into separate columns where each parent category becomes a column name. Default is FALSE.
args	Character vector of additional arguments passed directly to ExifTool (e.g., "-fast").
exiftool_path	Character. Path to the ExifTool executable. If NULL, the function attempts to auto-detect it.

Details

By default, all available tags are returned. You can limit the output to a predefined set of tags or provide a custom list of tag names.

This function calls ExifTool with CSV output enabled and numeric values returned where applicable. When parse_hs = TRUE, the HierarchicalSubject field is split into structured columns.

Value

A tibble where each row represents one image file and each column represents a metadata field.

See Also

• ct_get_hs() to retrieve hierarchical subjects

• ct_create_hs() to add hierarchical subjects

• ct_remove_hs() to remove hierarchical subjects

Examples

## Not run: 
# Example image path
image_path <- file.path(system.file("img", package = "ct"), "large.jpeg")

# Extract all metadata
ct_read_metadata(path = image_path)

# Extract a predefined standard set of metadata
ct_read_metadata(path = image_path, tags = "standard")

# Extract custom tags
ct_read_metadata(path = image_path,
                 tags = c("DateTimeOriginal", "GPSLatitude", "GPSLongitude"))

# Parse hierarchical subject fields into columns
ct_read_metadata(path = image_path,
                 tags = "standard",
                 parse_hs = TRUE)

## End(Not run)

ct documentation built on Oct. 22, 2026, 1:07 a.m.