cl-netpbm

API Reference

The following is a list of all user-facing parts of cl-netpbm.

If there are backwards-incompatible changes to anything listed here, they will be noted in the changelog and the author will feel bad.

Anything not listed here is subject to change at any time with no warning, so don't touch it.

Package NETPBM

READ-FROM-FILE (function)

(READ-FROM-FILE PATH)

Read a PPM image file from path, returning an array of pixels and more.

The primary return value will be a 2D array with dimensions (width height). Each element of the array will be a single pixel whose type depends on the image file format:

Two other values are returned:

READ-FROM-STREAM (function)

(READ-FROM-STREAM STREAM)

Read a PPM image file from stream, returning an array of pixels and more.

stream must be a binary input stream, specifically of (unsigned-byte 8)s unless you really know what you're doing.

The primary return value will be a 2D array with dimensions (width height). Each element of the array will be a single pixel whose type depends on the image file format:

Two other values are returned:

READ-TEXTURE-FROM-FILE (function)

(READ-TEXTURE-FROM-FILE PATH)

Read a PPM image file from path, returning an OpenGL-style array and more.

The primary return value will be an OpenGL-style array of type:

(simple-array (single-float 0.0 1.0) (* width height 3))

The vertical axis of the image will be flipped, which is what OpenGL expects.

Three values are returned: the array, the width, and the height.

READ-TEXTURE-FROM-STREAM (function)

(READ-TEXTURE-FROM-STREAM STREAM)

Read a PPM image file from stream, returning an OpenGL-style array and more.

stream must be a binary input stream, specifically of (unsigned-byte 8)s unless you really know what you're doing. The stream must contain a PPM formatted image — PBM and PGM images are not supported.

The primary return value will be an OpenGL-style array of type:

(simple-array (single-float 0.0 1.0) (* width height 3))

The vertical axis of the image will be flipped, which is what OpenGL expects.

Three values are returned: the array, the width, and the height.

WRITE-TO-FILE (function)

(WRITE-TO-FILE PATH DATA &KEY (IF-EXISTS NIL IF-EXISTS-GIVEN) (FORMAT :PPM) (ENCODING :BINARY)
               (MAXIMUM-VALUE (ECASE FORMAT (:PBM 1) ((:PGM :PPM) 255))))

Write a PPM image array data to a file at path.

Nothing is returned.

format must be one of :pbm, :pgm, :ppm.

encoding must be one of :binary, :ascii.

maximum-value must be the desired bit depth of the image (the maximum value any particular pixel can have). For PBM images it must be 1.

For PBM and PGM images, data must be a two dimensional array of integers between 0 and maximum-value inclusive.

For PPM images, data must be a two dimensional array of pixels, each of which must be a 3 element vector of integers between 0 and maximum-value inclusive.

WRITE-TO-STREAM (function)

(WRITE-TO-STREAM STREAM DATA &KEY (FORMAT :PPM) (ENCODING :BINARY)
                 (MAXIMUM-VALUE (ECASE FORMAT (:PBM 1) ((:PGM :PPM) 255))))

Write a PPM image array data to stream.

Nothing is returned.

stream must be a binary output stream, specifically of (unsigned-byte 8)s unless you really know what you're doing.

format must be one of :pbm, :pgm, :ppm.

encoding must be one of :binary, :ascii.

maximum-value must be the desired bit depth of the image (the maximum value any particular pixel can have). For PBM images it must be 1.

For PBM and PGM images, data must be a two dimensional array of integers between 0 and maximum-value inclusive.

For PPM images, data must be a two dimensional array of pixels, each of which must be a 3 element vector of integers between 0 and maximum-value inclusive.