Bitmap/Read an image through a pipe: Difference between revisions

[[Category:Input Output]]

 

This task is the ''opposite'' of the [[PPM conversion through a pipe]]. In this task, using a delegate tool (like '''cjpeg''', one of the netpbm package, or '''convert''' of the ImageMagick package) we read an image file and load it into the data storage type [[Basic bitmap storage|defined here]]. We can also use the code from [[Read ppm file]], so that we can use PPM format like a (natural) bridge between the foreign image format and our simple data storage.

 

=={{header|AutoHotkey}}==

{{works with | AutoHotkey_L}}

Uses [http://www.autohotkey.com/forum/viewtopic.php?t=16823 StdoutTovar.ahk]

; pipe in from imagemagick

img := ppm_read("", ppm) ;

#include bitmap_storage.ahk ; from http://rosettacode.org/wiki/Basic_bitmap_storage/AutoHotkey

#include run.ahk ; http://www.autohotkey.com/forum/viewtopic.php?t=16823

 

=={{header|C}}==

Here I've used '''convert''' by ImageMagick. It is up to the program to ''understand'' the source file type; in this way, we can read theoretically any image format ImageMagick can handle. The <tt>get_ppm</tt> function defined in [[Read ppm file]] is used.

 

 

 

#define MAXCMDBUF 100

}

return NULL;

=={{header|Go}}==

This example uses convert to convert the test image for the flood fill task. It reads through the pipe as required for this task, then writes as a .ppm file convenient for the flood fill task.

 

// Files required to build supporting package raster are found in:

log.Fatal(err)

}

=={{header|Julia}}==

{{works with|Julia|0.6}}

 

 

img = load("data/bitmapOutputTest.jpg")

=={{header|Kotlin}}==

{{works with|Ubuntu 16.04}}

The code for this is similar to that for the [[Bitmap/Read a PPM file]] task except that the .jpg file is converted via a pipe to .ppm format using the ImageMagick 'convert' tool and stored in a BasicBitmapStorage object. It is then converted to grayscale and saved back to disk as a .jpg file.

 

import java.awt.Color

}

}

 

Based off the Julia program.

 

=={{header|OCaml}}==

The <code>read_ppm</code> function of the page [[read ppm file]] and used by the code below would need to be changed to take as parameter an input channel instead of the filename.

if not(Sys.file_exists filename)

then failwith(Printf.sprintf "the file %s does not exist" filename);

let img = read_ppm ~ic in

(img)

 

 

=={{header|Python}}==

"""

Adapted from https://stackoverflow.com/questions/26937143/ppm-to-jpeg-jpg-conversion-for-python-3-4-1

im = Image.open("boxes_1.jpg")

im.save("boxes_1v2.ppm")

Does not need to pipe through a conversion utility

because the Pillow module does the conversion.

=={{header|Racket}}==

 

(define (read-ppm port)

bmp)

 

=={{header|Raku}}==

(formerly Perl 6)

{{works with|Rakudo|2017.09}}

 

Uses imagemagick convert to pipe the image in.

 

class Bitmap {

has UInt ($.width, $.height);

{ Pixel.new(R => .[0], G => .[1], B => .[2]) };

 

 

See [https://github.com/thundergnat/rc/blob/master/img/camelia.png camelia image here].

=={{header|Ruby}}==

 

def self.read_ppm(ios)

format = ios.gets.chomp

max_colour = ios.gets.chomp

 

ios.close

raise StandardError, "file '#{filename}' does not start with the expected header"

ios.binmode if PIXMAP_BINARY_FORMATS.include?(format)

 

height.times do |y|

width.times do |x|

# read 3 bytes

red, green, blue = case format

end

end

end

 

=={{header|Tcl}}==

{{works with|Tcl|8.6}}

{{libheader|Tk}}

 

proc magickalReadImage {bufferImage fileName} {

close $f

}

 

=={{header|zkl}}==

 

Using the convert utility by ImageMagick:

{{omit from|PARI/GP}}