Write images in TIFF format

Write images into a TIFF file.

Usage

write_tif(
  img,
  path,
  bits_per_sample = "auto",
  compression = "none",
  overwrite = FALSE,
  msg = TRUE,
  tags_to_write = NULL
)

tif_write(
  img,
  path,
  bits_per_sample = "auto",
  compression = "none",
  overwrite = FALSE,
  msg = TRUE,
  tags_to_write = NULL
)

Arguments

img

An array representing the image.

• For a multi-plane, grayscale image, use a 3-dimensional array img[y, x, plane].

• For a multi-channel, single-plane image, use a 4-dimensional array with a redundant 4th slot img[y, x, channel, ] (see ijtiff_img 'Examples' for an example).

• For a multi-channel, multi-plane image, use a 4-dimensional array img[y, x, channel, plane].

path

Path to the TIFF file to write to.

bits_per_sample

Number of bits per sample (numeric scalar). Supported values are 8, 16, and 32. The default "auto" automatically picks the smallest workable value based on the maximum element in img. For example, if the maximum element in img is 789, then 16-bit will be chosen because 789 is greater than 2 ^ 8 - 1 but less than or equal to 2 ^ 16 - 1.

compression

A string, the desired compression algorithm. Must be one of "none", "LZW", "PackBits", "RLE", "JPEG", "deflate" or "Zip". If you want compression but don't know which one to go for, I recommend "Zip", it gives a large file size reduction and it's lossless. Note that "deflate" and "Zip" are the same thing. Avoid using "JPEG" compression in a TIFF file if you can; I've noticed it can be buggy.

overwrite

If writing the image would overwrite a file, do you want to proceed?

msg

Print an informative message about the image being written?

tags_to_write

A named list of TIFF tags to write. Tag names are case-insensitive and hyphens/underscores are ignored (e.g., "X_Resolution", "x-resolution", and "xresolution" are all equivalent). Supported tags are:

• xresolution - Numeric value for horizontal resolution in pixels per unit

• yresolution - Numeric value for vertical resolution in pixels per unit

• resolutionunit - Integer: 1 (none), 2 (inch), or 3 (centimeter)

• orientation - Integer 1-8 for image orientation

• xposition - Numeric value for horizontal position in resolution units

• yposition - Numeric value for vertical position in resolution units

• copyright - Character string for copyright notice

• artist - Character string for creator name

• documentname - Character string for document name

• datetime - Date/time (character, Date, or POSIXct)

• imagedescription - Character string for image description

Value

The input img (invisibly).

See also

read_tif()

Author

Simon Urbanek wrote most of this code for the 'tiff' package. Rory Nolan lifted it from there and changed it around a bit for this 'ijtiff' package. Credit should be directed towards Lord Urbanek.

Examples

img <- read_tif(system.file("img", "Rlogo.tif", package = "ijtiff"))
#> Reading image from /github/home/R/x86_64-pc-linux-gnu-library/4.5/ijtiff/img/Rlogo.tif
#> Reading an 8-bit, float image with dimensions 76x100x4x1 (y,x,channel,frame) . . .
temp_dir <- tempdir()

# Basic write
write_tif(img, paste0(temp_dir, "/", "Rlogo"))
#> Writing /tmp/RtmphGTfxi/Rlogo.tif: an 8-bit, 76x100 pixel image of unsigned integer type with 4 channels and 1 frame . . .
#>  Done.

# Write with tags
write_tif(img, paste0(temp_dir, "/", "Rlogo_with_tags"),
          tags_to_write = list(
            artist = "R Core Team",
            copyright = "(c) 2024",
            imagedescription = "The R logo"
          ))
#> Writing /tmp/RtmphGTfxi/Rlogo_with_tags.tif: an 8-bit, 76x100 pixel image of unsigned integer type with 4 channels and 1 frame . . .
#>  Done.

img <- matrix(1:4, nrow = 2)
write_tif(img, paste0(temp_dir, "/", "tiny2x2"))
#> Writing /tmp/RtmphGTfxi/tiny2x2.tif: an 8-bit, 2x2 pixel image of unsigned integer type with 1 channel and 1 frame . . .
#>  Done.
list.files(temp_dir, pattern = "tif$")
#> [1] "Rlogo.tif"           "Rlogo_with_tags.tif" "tiny2x2.tif"