I am taking a PNG image from a url as below.
I want to convert the PNG image to JPEG without saving disk with PHP.
Finally I want to assign JPEG image to $content_jpg variable.
$url = 'http://www.example.com/image.png';
$content_png = file_get_contents($url);
$content_jpg=;
Simplified answer is,
// PNG image url
$url = 'http://www.example.com/image.png';
// Create image from web image url
$image = imagecreatefrompng($url);
// Start output buffer
ob_start();
// Convert image
imagejpeg($image, NULL,100);
imagedestroy($image);
// Assign JPEG image content from output buffer
$content_jpg = ob_get_clean();
You want to use the gd library for this. Here's an example which will take a png image and output a jpeg one. If the image is transparent, the transparency will be rendered as white instead.
<?php
$file = "myimage.png";
$image = imagecreatefrompng($file);
$bg = imagecreatetruecolor(imagesx($image), imagesy($image));
imagefill($bg, 0, 0, imagecolorallocate($bg, 255, 255, 255));
imagealphablending($bg, TRUE);
imagecopy($bg, $image, 0, 0, 0, 0, imagesx($image), imagesy($image));
imagedestroy($image);
header('Content-Type: image/jpeg');
$quality = 50;
imagejpeg($bg);
imagedestroy($bg);
?>
Related
Currently I would like to create a transparent png with the lowest quality .
The code:
<?php
function createImg ($src, $dst, $width, $height, $quality) {
$newImage = imagecreatetruecolor($width,$height);
$source = imagecreatefrompng($src); //imagecreatefrompng() returns an image identifier representing the image obtained from the given filename.
imagecopyresampled($newImage,$source,0,0,0,0,$width,$height,$width,$height);
imagepng($newImage,$dst,$quality); //imagepng() creates a PNG file from the given image.
return $dst;
}
createImg ('test.png','test.png','1920','1080','1');
?>
However, there are some problems:
Do I need to specific a png file before creating any new file? Or can I create without any existing png file?
Warning: imagecreatefrompng(test.png): failed to open stream: No such file or directory in
C:\DSPadmin\DEV\ajax_optipng1.5\create.php on line 4
Although there are error message , it still generate a png file , however, what I found that is the file is a black color image , do I need to specific any parameter to make it transparent?
Thanks.
To 1)
imagecreatefrompng('test.png') tries to open the file test.png which then can be edited with GD functions.
To 2)
To enable saving of the alpha channel imagesavealpha($img, true); is used.
The following code creates a 200x200px sized transparent image by enabling alpha saving and filling it with transparency.
<?php
$img = imagecreatetruecolor(200, 200);
imagesavealpha($img, true);
$color = imagecolorallocatealpha($img, 0, 0, 0, 127);
imagefill($img, 0, 0, $color);
imagepng($img, 'test.png');
Take a look at:
imagecolorallocatealpha
imagefill
An example function copies transparent PNG files:
<?php
function copyTransparent($src, $output)
{
$dimensions = getimagesize($src);
$x = $dimensions[0];
$y = $dimensions[1];
$im = imagecreatetruecolor($x,$y);
$src_ = imagecreatefrompng($src);
// Prepare alpha channel for transparent background
$alpha_channel = imagecolorallocatealpha($im, 0, 0, 0, 127);
imagecolortransparent($im, $alpha_channel);
// Fill image
imagefill($im, 0, 0, $alpha_channel);
// Copy from other
imagecopy($im,$src_, 0, 0, 0, 0, $x, $y);
// Save transparency
imagesavealpha($im,true);
// Save PNG
imagepng($im,$output,9);
imagedestroy($im);
}
$png = 'test.png';
copyTransparent($png,"png.png");
?>
1) You can create a new png file without any existing one.
2) You get a black color image because you use imagecreatetruecolor();. It creates a highest quality image with a black background. As you need a lowest quality image use imagecreate();
<?php
$tt_image = imagecreate( 100, 50 ); /* width, height */
$background = imagecolorallocatealpha( $tt_image, 0, 0, 255, 127 ); /* In RGB colors- (Red, Green, Blue, Transparency ) */
header( "Content-type: image/png" );
imagepng( $tt_image );
imagecolordeallocate( $background );
imagedestroy( $tt_image );
?>
You can read more in this article: How to Create an Image Using PHP
Trying to put watermark to an image
Image Original Size :- 10.8 MB
After watermarking:- New Image Size:- 37.9 MB
$text = "Afrophoto";
//the text i want as watermark
//create a new image
$newImg = imagecreatefromjpeg($image);
//set the watermark font color to red
$fontColor = imagecolorallocate($newImg, 255, 255, 255);
$font_file = 'fontArial.ttf';
list($width, $height) = getimagesize($image);
//write the watermark on the created image
imagefttext($newImg, 50, 50, $j, $i, $width - 100, $height - 100, $text);
//output the new image with a watermark to a file
imagejpeg($newImg,"uploads/".$_FILES[$field]['name'],100);
imagepng($newImg,"uploads/".$_FILES[$field]['name'].".png");
imagedestroy($newImg);
Here I used Png image
Actual size banned.png: 53.2KB
with watermark bbimage_3.png: 40.8 KB
<?php
$imageURL = "banned.png";
list($width,$height) = getimagesize($imageURL);
$imageProperties = imagecreatetruecolor($width, $height);
$targetLayer = imagecreatefrompng($imageURL);
imagecopyresampled($imageProperties, $targetLayer, 0, 0, 0, 0, $width, $height, $width, $height);
$WaterMarkText = 'CONFIDENTIAL';
$watermarkColor = imagecolorallocate($imageProperties, 191,191,191);
imagestring($imageProperties, 5, 130, 117, $WaterMarkText, $watermarkColor);
imagepng($imageProperties, 'bbimage_3.png');
header('Content-type: image/jpeg');
imagepng ($imageProperties);
imagedestroy($targetLayer);
imagedestroy($imageProperties);
?>
imagecopy: This function copies source image onto destination image by overwriting destination image pixels.
While merging png images with transparent background as a watermark, imagecopymerge() function will not preserve transparency onto the destination. So, imagecopy() is preferable for image watermarking.
Is it possible to have png images on my server but have a php script that converts them to jpg (and compresses them) and caches them when viewed?
You can use this script for convert PNG image into JPEG image.
$input_file = "test.png";
$output_file = "test.jpg";
$input = imagecreatefrompng($input_file);
list($width, $height) = getimagesize($input_file);
$output = imagecreatetruecolor($width, $height);
imagecopy($output, $input, 0, 0, 0, 0, $width, $height);
imagejpeg($output, $output_file);
You can go through this #Alexandre Jasmin Answer.
yes it is possible, you can google it using phrase "png convert to jpg php"
Use PHP to convert PNG to JPG with compression?
Currently I would like to create a transparent png with the lowest quality .
The code:
<?php
function createImg ($src, $dst, $width, $height, $quality) {
$newImage = imagecreatetruecolor($width,$height);
$source = imagecreatefrompng($src); //imagecreatefrompng() returns an image identifier representing the image obtained from the given filename.
imagecopyresampled($newImage,$source,0,0,0,0,$width,$height,$width,$height);
imagepng($newImage,$dst,$quality); //imagepng() creates a PNG file from the given image.
return $dst;
}
createImg ('test.png','test.png','1920','1080','1');
?>
However, there are some problems:
Do I need to specific a png file before creating any new file? Or can I create without any existing png file?
Warning: imagecreatefrompng(test.png): failed to open stream: No such file or directory in
C:\DSPadmin\DEV\ajax_optipng1.5\create.php on line 4
Although there are error message , it still generate a png file , however, what I found that is the file is a black color image , do I need to specific any parameter to make it transparent?
Thanks.
To 1)
imagecreatefrompng('test.png') tries to open the file test.png which then can be edited with GD functions.
To 2)
To enable saving of the alpha channel imagesavealpha($img, true); is used.
The following code creates a 200x200px sized transparent image by enabling alpha saving and filling it with transparency.
<?php
$img = imagecreatetruecolor(200, 200);
imagesavealpha($img, true);
$color = imagecolorallocatealpha($img, 0, 0, 0, 127);
imagefill($img, 0, 0, $color);
imagepng($img, 'test.png');
Take a look at:
imagecolorallocatealpha
imagefill
An example function copies transparent PNG files:
<?php
function copyTransparent($src, $output)
{
$dimensions = getimagesize($src);
$x = $dimensions[0];
$y = $dimensions[1];
$im = imagecreatetruecolor($x,$y);
$src_ = imagecreatefrompng($src);
// Prepare alpha channel for transparent background
$alpha_channel = imagecolorallocatealpha($im, 0, 0, 0, 127);
imagecolortransparent($im, $alpha_channel);
// Fill image
imagefill($im, 0, 0, $alpha_channel);
// Copy from other
imagecopy($im,$src_, 0, 0, 0, 0, $x, $y);
// Save transparency
imagesavealpha($im,true);
// Save PNG
imagepng($im,$output,9);
imagedestroy($im);
}
$png = 'test.png';
copyTransparent($png,"png.png");
?>
1) You can create a new png file without any existing one.
2) You get a black color image because you use imagecreatetruecolor();. It creates a highest quality image with a black background. As you need a lowest quality image use imagecreate();
<?php
$tt_image = imagecreate( 100, 50 ); /* width, height */
$background = imagecolorallocatealpha( $tt_image, 0, 0, 255, 127 ); /* In RGB colors- (Red, Green, Blue, Transparency ) */
header( "Content-type: image/png" );
imagepng( $tt_image );
imagecolordeallocate( $background );
imagedestroy( $tt_image );
?>
You can read more in this article: How to Create an Image Using PHP
Is there any script that resizes an external image and outputs it ?
For example, i want to resize all external square images to 130X130.
Like this
http://mydomain.com/script/resize.php?url=http://otherdomain.com/image.png
EDIT:
Facebook also is an example maybe
https://s-external.ak.fbcdn.net/safe_image.php?d=AQCYX3NIE5gMyujT&url=http%3A%2F%2Fi2.ytimg.com%2Fvi%2FyoLeJNjIVZk%2Fhqdefault.jpg
any help appreciated.
Thanks
// Content type
header('Content-Type: image/jpeg');
//get image from internet and save it into local disk
$url = 'http://www.google.com/images/srpr/logo3w.png';
$img = 'google.png';
file_put_contents($img, file_get_contents($url));
//get current size and set new size
list($width, $height) = getimagesize($img);
$new_width = 130;
$new_height = 130;
// genarate resized image copy
$image_p = imagecreatetruecolor($new_width, $new_height);
$image = imagecreatefrompng($img);
imagecopyresampled($image_p, $image, 0, 0, 0, 0, $new_width, $new_height, $width, $height);
// flush image to browser
imagejpeg($image_p, null, 100);
// save resised image to disk
imagejpeg($image_p, "newimage.jpg",100);
Use this code only if you want to resize and save on your application otherwise above example is enough.
Take a look at this thread. You can write your own code to resize images or use TimThumb script.
if you dont want to save them than you can just set the with and hight with html or css
<img height="130px" with="130px;" src="somesite.com/img.jpg"></img>