imagesetpixel

imagesetpixel — Set the RGB value of a pixel inside a previously opened or created image.

Description

Set the RGB value of a pixel inside a previously opened or created image. An image can be loaded with imageload. An empty image can be created with imagecreate and saved with imagesave.

Syntax

imagesetpixel iimagenum, ax, ay, ared, agreen, ablue
imagesetpixel iimagenum, kx, ky, kred, kgreen, kblue

Initialization

iimagenum -- the reference of the image.. It should be a value returned by imageload or imagecreate.

Performance

ax (kx) -- horizontal pixel position (must be a float from 0 to 1).

ay (ky) -- vertical pixel position (must be a float from 0 to 1).

ared (kred) -- red value of the pixel (mapped to a float from 0 to 1).

agreen (kgreen) -- green value of the pixel (mapped to a float from 0 to 1).

ablue (kblue) -- blue value of the pixel (mapped to a float from 0 to 1).

Examples

Here is an example of the imagesetpixel opcode. It uses the file imageopcodes.csd.

Example 376. Example of the imagesetpixel opcode.

<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
-n ;no sound output
</CsOptions>
<CsInstruments>

sr=48000
ksmps=1
nchnls=2

; this test .csd copies image.png into a new file 'imageout.png'

giimage1 imageload "image.png"
giimagew, giimageh imagesize giimage1
giimage2 imagecreate giimagew,giimageh

    instr 1

kndx = 0
kx_ linseg 0, p3, 1
;print imagewidth and imageheigth of image.png
prints "imagewidth = %f pixels, imageheigth = %f pixels\\n", giimagew, giimageh

myloop:
ky_ = kndx/(giimageh)
kr_, kg_, kb_ imagegetpixel giimage1, kx_, ky_
imagesetpixel giimage2, kx_, ky_, kr_, kg_, kb_
loop_lt kndx, 0.5, giimageh, myloop
    endin

    instr 2

imagesave giimage2, "imageout.png"
    endin

    instr 3
imagefree giimage1
imagefree giimage2
    endin

</CsInstruments>
<CsScore>

i1 1 1
i2 2 1
i3 3 1
e

</CsScore>
</CsoundSynthesizer>


See Also

imageload, imagecreate, imagesize, imagesave, imagegetpixel, imagefree

Credits

Author: Cesare Marilungo

New in version 5.08