Image resizing with PHP advice
From previous experiences, I've noticed that I'm not very good at integrating 'scripts' created by others, with my own existing code, as of now. I need some advice on understanding what this person is saying about resizing images with PHP:
In the comments, he's written:
// Parameters need to be passed in through the URL's query string:
// image absolute path of local image starting with "/" (e.g. /images/toast.jpg)
// width maximum width of final image in pixels (e.g. 700)
// height maximum height of final image in pixels (e.g. 700)
Then, he gives an actual example, also as a comment:
// Resizing and cropping a JPEG into a square:
// <img src="/image.php/image-name.jpg?width=100&height=100&cropratio=1:1&image=/path/to/image.jpg" alt="Don't forget your alt text" />
I am guessing, he wants the user of the script to have something similar to the above img src
. So, my question is: How will I actually make the source of my pictures similar to the example above? Below is some of the code I have. It shows how I am saving the pictures and HOW I am echoing/displaying them. It's from uploader.php
:
move_uploaded_file($_FILES["file"]["tmp_name"],
"profileportraits/" . $_FILES["file"]["name"]);
echo "Stored in: " . "profileportraits/" . $_FILES["file"]["name"];
Once the photo has been saved in t开发者_如何学运维he folder, I save the file path in a MySQL table and later call the file path to display the picture (Below Code). It's from profile.php
echo "<img src=\"{$row['PortraitPath']}\" />";
Therefore, how will I pass the parameters similar to the one in the 'script example' if I am using the above img src to display the 'actual' picture?
THANK YOU.
$width = 100;
$height = 100;
src="/image.php?width={$width}&height={$height}"
You can use the following code to resize the image... once you got all the params
/**
* Gets the jpeg contents of the resized version of an already uploaded image
* (Returns false if the file was not an image)
*
* @param string $input_name The name of the file on the disk
* @param int $maxwidth The desired width of the resized image
* @param int $maxheight The desired height of the resized image
* @param true|false $square If set to true, takes the smallest of maxwidth and
* maxheight and use it to set the dimensions on the new image. If no
* crop parameters are set, the largest square that fits in the image
* centered will be used for the resize. If square, the crop must be a
* square region.
* @param int $x1 x coordinate for top, left corner
* @param int $y1 y coordinate for top, left corner
* @param int $x2 x coordinate for bottom, right corner
* @param int $y2 y coordinate for bottom, right corner
* @param bool $upscale Resize images smaller than $maxwidth x $maxheight?
* @return false|mixed The contents of the resized image, or false on failure
*/
function get_resized_image_from_existing_file($input_name, $maxwidth, $maxheight, $square = FALSE, $x1 = 0, $y1 = 0, $x2 = 0, $y2 = 0, $upscale = FALSE) {
// Get the size information from the image
$imgsizearray = getimagesize($input_name);
if ($imgsizearray == FALSE) {
return FALSE;
}
// Get width and height
$width = $imgsizearray[0];
$height = $imgsizearray[1];
// make sure we can read the image
$accepted_formats = array(
'image/jpeg' => 'jpeg',
'image/pjpeg' => 'jpeg',
'image/png' => 'png',
'image/x-png' => 'png',
'image/gif' => 'gif'
);
// make sure the function is available
$load_function = "imagecreatefrom" . $accepted_formats[$imgsizearray['mime']];
if (!is_callable($load_function)) {
return FALSE;
}
// crop image first?
$crop = TRUE;
if ($x1 == 0 && $y1 == 0 && $x2 == 0 && $y2 == 0) {
$crop = FALSE;
}
// how large a section of the image has been selected
if ($crop) {
$region_width = $x2 - $x1;
$region_height = $y2 - $y1;
} else {
// everything selected if no crop parameters
$region_width = $width;
$region_height = $height;
}
// determine cropping offsets
if ($square) {
// asking for a square image back
// detect case where someone is passing crop parameters that are not for a square
if ($crop == TRUE && $region_width != $region_height) {
return FALSE;
}
// size of the new square image
$new_width = $new_height = min($maxwidth, $maxheight);
// find largest square that fits within the selected region
$region_width = $region_height = min($region_width, $region_height);
// set offsets for crop
if ($crop) {
$widthoffset = $x1;
$heightoffset = $y1;
$width = $x2 - $x1;
$height = $width;
} else {
// place square region in the center
$widthoffset = floor(($width - $region_width) / 2);
$heightoffset = floor(($height - $region_height) / 2);
}
} else {
// non-square new image
$new_width = $maxwidth;
$new_height = $maxwidth;
// maintain aspect ratio of original image/crop
if (($region_height / (float)$new_height) > ($region_width / (float)$new_width)) {
$new_width = floor($new_height * $region_width / (float)$region_height);
} else {
$new_height = floor($new_width * $region_height / (float)$region_width);
}
// by default, use entire image
$widthoffset = 0;
$heightoffset = 0;
if ($crop) {
$widthoffset = $x1;
$heightoffset = $y1;
}
}
// check for upscaling
// @todo This ignores squares, coordinates, and cropping. It's probably not the best idea.
// Size checking should be done in action code, but for backward compatibility
// this duplicates the previous behavior.
if (!$upscale && ($height < $new_height || $width < $new_width)) {
// zero out offsets
$widthoffset = $heightoffset = 0;
// determine if we can scale it down at all
// (ie, if only one dimension is too small)
// if not, just use original size.
if ($height < $new_height && $width < $new_width) {
$ratio = 1;
} elseif ($height < $new_height) {
$ratio = $new_width / $width;
} elseif ($width < $new_width) {
$ratio = $new_height / $height;
}
$region_height = $height;
$region_width = $width;
$new_height = floor($height * $ratio);
$new_width = floor($width * $ratio);
}
// load original image
$orig_image = $load_function($input_name);
if (!$orig_image) {
return FALSE;
}
// allocate the new image
$newimage = imagecreatetruecolor($new_width, $new_height);
if (!$newimage) {
return FALSE;
}
// create the new image
$rtn_code = imagecopyresampled( $newimage,
$orig_image,
0,
0,
$widthoffset,
$heightoffset,
$new_width,
$new_height,
$region_width,
$region_height );
if (!$rtn_code) {
return FALSE;
}
// grab contents for return
ob_start();
imagejpeg($newimage, null, 90);
$jpeg = ob_get_clean();
imagedestroy($newimage);
imagedestroy($orig_image);
return $jpeg;
}
Hope this helps..
Thanks Chetan sharma
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