imagecopyresampled
(PHP 4 >= 4.0.6)
imagecopyresampled -- Copy and resize part of an image
with resampling
Description
bool imagecopyresampled ( resource dst_im, resource src_im,
int dstX, int dstY, int srcX, int srcY, int dstW, int dstH,
int srcW, int srcH)
imagecopyresampled() copies a rectangular portion of one
image to another image, smoothly interpolating pixel values
so that, in particular, reducing the size of an image still
retains a great deal of clarity. Returns TRUE on success
or FALSE on failure. dst_im is the destination image, src_im
is the source image identifier. If the source and destination
coordinates and width and heights differ, appropriate stretching
or shrinking of the image fragment will be performed. The
coordinates refer to the upper left corner. This function
can be used to copy regions within the same image (if dst_im
is the same as src_im) but if the regions overlap the results
will be unpredictable.
Note: There is a problem due to palette image limitations
(255+1 colors). Resampling or filtering an image commonly
needs more colors than 255, a kind of approximation is used
to calculate the new resampled pixel and its color. With
a palette image we try to allocate a new color, if that
failed, we choose the closest (in theory) computed color.
This is not always the closest visual color. That may produce
a weird result, like blank (or visually blank) images. To
skip this problem, please use a truecolor image as a destination
image, such as one created by imagecreatetruecolor().
Note: imagecopyresampled() requires GD 2.0.l or greater.
See also imagecopyresized().
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