Read Image — ray_read_image • rayimage

Reads an image from a file/array/matrix. From files, supports JPEG, PNG, TIFF, TGA, BMP, PSD, GIF, HDR, PIC, PNM, and EXR images.

ray_read_image(
  image,
  convert_to_array = FALSE,
  preview = FALSE,
  source_linear = NA,
  normalize = FALSE,
  normalize_to = CS_ACESCG,
  normalize_adapt_white = TRUE,
  assume_colorspace = NULL,
  assume_white = NULL,
  ...
)

Arguments

image: 3-layer RGB/4-layer RGBA array, rayimg class, or filename of an image.
convert_to_array: Default FALSE. Whether to convert 2D B&W images/matrices to RGBA arrays.
preview: Default FALSE. If TRUE, it will display the image in addition to returning it.
source_linear: Default NA, automatically determined based on the image type. Whether the image source is linear data or sRGB. TRUE for matrices, arrays, and floating-point HDR formats (EXR, HDR); FALSE for all other file-based formats (e.g., jpeg, png, tiff, tga, bmp, psd, gif, pic, pnm).
normalize: Default FALSE. If TRUE, convert to normalize_to space on read. Note that rayimg inputs will keep their colorspace and ignore this option–use render_convert_colorspace() to change an existing rayimg to a new colorspace.
normalize_to: Default CS_ACESCG. Target colorspace when normalize=TRUE.
normalize_adapt_white: Default TRUE. If TRUE, Bradford-adapt source white to target white.
assume_colorspace: Default NULL. A colorspace descriptor (e.g., CS_SRGB, CS_ACESCG). If given, the loaded image will be tagged with this space rather than the default inferred by file type. No pixel conversion is performed unless normalize=TRUE.
assume_white: Default NULL. Scene/display white for the loaded image. Either a named white ("D60","D65","D50","D55","D75","E") or XYZ with Y=1. If NULL, uses assume_colorspace$white_xyz.
...: Arguments to pass to jpeg::readJPEG, png::readPNG, tiff::readTIFF, or libopenexr::read_exr() for supported formats.

Value

A rayimg RGBA array.

Examples

if(run_documentation()){
#Write as a png
tmparr = tempfile(fileext=".png")
ray_read_image(dragon) |>
 ray_write_image(tmparr)
ray_read_image(tmparr) |>
 plot_image()
}

if(run_documentation()){
#Write as a JPEG (passing quality arguments via ...)
tmparr = tempfile(fileext=".jpg")
ray_read_image(dragon) |>
 ray_write_image(tmparr, quality = 0.2)
ray_read_image(tmparr) |>
 plot_image()
}
#> Warning: JPEG decompression: Caution: quantization tables are too coarse for baseline JPEG

if(run_documentation()){
#Write as a tiff
tmparr = tempfile(fileext=".tiff")
ray_read_image(dragon) |>
 ray_write_image(tmparr)
ray_read_image(tmparr) |>
  plot_image()
}
#> Warning: TIFFReadDirectory: Sum of Photometric type-related color channels and ExtraSamples doesn't match SamplesPerPixel. Defining non-color channels as ExtraSamples.


if(run_documentation()){
#Write as an exr
tmparr = tempfile(fileext=".exr")
ray_read_image(dragon) |>
 ray_write_image(tmparr)
ray_read_image(tmparr) |>
  plot_image()
}