Crate include_pnm 

Embed PNM images directly into Rust code.

This supports most PNM files in a mostly reasonable way. The idea here is that PNM is a very simple format that is also compressible enough to embed directly into version control repositories, and so, very suited to loading in at compile time.

Most PNM images are supported, with the primary exception applying to PPM images and 3-channel PAM images: these must have a MAXVAL of 255 or 65535 in order to be loaded at all.

Conversions

Similar to netpbm, all formats of PNM images are supported, and then converted to the result depending on the mode requested. Color space is completely ignored when converting between formats, and conversion is only allowed in the forward direction, where e.g. grayscale images can be converted to RGB by duplicating values three times.

Similarly, conversion from 8-bit color to 16-bit color is done under the assumption that the scaling does not change, and all values get scaled by 65535/255.

“Indexed” images

While PGM and 1-channel PAM images may have any allowed MAXVAL, images without a MAXVAL of 1, 255, or 65535 may not be converted into any other color format, under the assumption that they were intended to reference palette indices instead of colors.

Tracking included images

On stable Rust, you must add a build script and output cargo:rerun-if-changed=path for each included image to ensure that your crate recompiles whenever the image files change. However, on nightly Rust with the nightly feature enabled, the unstable track_path feature will be used so this happens automatically.

Macros

include_pbm

Include a PBM image as a 2D array of bool.

include_pbma

Include a “PBMA” image as a 2D array of [bool; 2].

include_pgm

Include a PGM image as a 2D array of u8.

include_pgm16

Include a PGM image as a 2D array of u16.

include_pgma

Include a “PGMA” image as a 2D array of [u8; 2].

include_pgma16

Include a “PGMA” image as a 2D array of [u16; 2].

include_pnm

Include a PAM image as a 2D array of the specified type and number of channels.

include_ppm

Include a PPM image as a 2D array of [u8; 3].

include_ppm16

Include a PPM image as a 2D array of [u16; 3].

include_ppma

Include a “PPMA” image as a 2D array of [u8; 4].

include_ppma16

Include a “PPMA” image as a 2D array of [u16; 4].