It should be clear that the set version of the function doesn't change the image it self, just the resource in memory, which probably is fine if you didn't save the image yet. If your use case is for an image that is already on disk, image you should always do something like:
imageresolution($img, 300, 300);
imagepng($img, $filname, $quality);
imageresolution
(PHP 7 >= 7.2.0)
imageresolution — Get or set the resolution of the image
설명
imageresolution() allows to set and get the resolution of
an image in DPI (dots per inch). If none of the optional parameters is given,
the current resolution is returned as indexed array. If only
res_x is given, the horizontal and vertical resolution
are set to this value. If both optional parameters are given, the horizontal
and vertical resolution are set to these values, respectively.
The resolution is only used as meta information when images are read from and written to formats supporting this kind of information (curently PNG and JPEG). It does not affect any drawing operations. The default resolution for new images is 96 DPI.
인수
-
image -
imagecreatetruecolor() 등의 이미지 생성 함수에서 반환한 이미지 자원.
-
res_x -
The horizontal resolution in DPI.
-
res_y -
The vertical resolution in DPI.
반환값
When used as getter (that is without the optional parameters), it returns
TRUE on success, 실패 시 FALSE를 반환합니다.
When used as setter (that is with one or both optional parameters given),
it returns an indexed array of the horizontal and vertical resolution on
success, 실패 시 FALSE를 반환합니다.
예제
Example #1 Setting and getting the resolution of an image
<?php
$im = imagecreatetruecolor(100, 100);
imageresolution($im, 200);
print_r(imageresolution($im));
imageresolution($im, 300, 72);
print_r(imageresolution($im));
?>
위 예제의 출력:
Array
(
[0] => 200
[1] => 200
)
Array
(
[0] => 300
[1] => 72
)
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User Contributed Notes 1 note
fernando dot fonseca at afteryou dot pt ¶
3 years ago
