I have two graphics file.
The first image - a background image in JPG format
The second file - PNG file with the figure in the center filled with white, with a black border on a path. The main background of transparent PNG file.
Question:
How to merge two files with transparency (see image example)? Background of the first file should be placed inside the figure in the second file.
Scheme:
Images:
PNG file - profiles.in.ua/tmp/sample2.jpg
JPG file - profiles.in.ua/tmp/sample1.png
PHP code:
$mask = new Imagick(realpath('mask.png'));
$pattern = new Imagick(realpath('pattern.jpg'));
$pattern->resizeImage($mask->width, $mask->height, Imagick::FILTER_LANCZOS, 1);
$pattern->compositeImage($mask, Imagick::COMPOSITE_ATOP, 0, 0);
header("Content-Type: image/png");
echo $pattern->getImageBlob();
$mask->destroy();
$pattern->destroy();
Assuming the mask image is always made exclusively of white pixels (which should be overwritten with the pattern), black pixels (which should overwrite the pattern), and transparent pixels (which should remain transparent), you can get this effect by compositing the pattern into the non-transparent pixels in the mask, then darkening the result with the mask.
The PNG file you provided did not have a transparent background as specified; instead it was white and grey hatching. I had to edit it first to add a transparent background before this code worked.
$mask = new Imagick(realpath('sample1.png'));
$pattern = new Imagick(realpath('sample2.jpg'));
$pattern->resizeImage($mask->width, $mask->height, Imagick::FILTER_LANCZOS, 1);
$image = clone($mask);
$image->compositeImage($pattern, Imagick::COMPOSITE_IN, 0, 0);
$image->compositeImage($mask, Imagick::COMPOSITE_DARKEN, 0, 0);
header("Content-Type: image/png");
echo $image;
$image->destroy();
$mask->destroy();
$pattern->destroy();
You need to fix the end of your code. All good until the end.
$base->writeImage('output.png');
header("Content-Type: image/png");
echo $base;
Update me :)
Related
We're using a CMS with WideImage built in and no scope to change this, however we've come up against a situation where we need to produce 300x300 images.
However the images that are uploaded at approx 100x100 in jpg and png format with various levels of transparency.
I'm trying to create a 300x300 canvas, and place the 100x100 image inside of it - however I want both the canvas to remain transparent, and the image placed on top to keep its transparency.
I've got
$image = WideImage::loadFromFile( $this->local_path );
$canvas = WideImage::createTrueColorImage(300, 300);
$canvas_bg = $canvas->allocateColor(255, 255, 255);
$canvas->fill(0, 0, $canvas_bg);
$resized_image = $canvas->merge($image);
However this obviously just adds a white background to the canvas, I cant figure out from their documentation how to make it transparent.
Thanks
How about:
$image = WideImage::loadFromFile($this->local_path);
$resized_image = $image->resizeCanvas(300, 300, 0, 0);
You can specify the X and Y location of the image within the new canvas as well as its width and height. $image->resizeCanvas(300, 300, "center", "center") works quite well.
I created an image from other image with the following code,
imagepng(imagecreatefromstring(file_get_contents(destination path)),source_path);
The image was created,But when i try to create a png image from a transparent image,The background become black color.
Why this happens?How to solve this?
If you look at the GD Documentation you'll find the alpha based functions. Taken directly from imagesavealpha() is the following code that opens a png and outputs it with transparency maintained;
// Load a png image with alpha channels
$png = imagecreatefrompng('./alphachannel_example.png');
// Do required operations
// (So any resizing/rotating/cropping etc)
// Turn off alpha blending and set alpha flag
imagealphablending($png, false);
imagesavealpha($png, true);
// Output image to browser
header('Content-Type: image/png');
imagepng($png);
I am trying to do a watermark mark with the php code, and everything seems to work fine, until I put a transparent PNG file to a GIF. This what happens:
So instead of transparent black watermark, I get this semi solid green thing on the top.
The watermark is
I use the following php code:
...
$image = imagecreatefromgif($filepath);;
$watermark_image = imagecreatefrompng($wm_filepath);
imagealphablending($watermark_image, false);
imagesavealpha($watermark_image, true);
imagegif($image, $filepath);
imagedestroy($image);
imagecopy($image, $watermark_image, $offset['x'], $offset['y'], 0, 0, imagesx($watermark_image), imagesy($watermark_image) );
p.s. I have to mention that I tried to combine different settings using
imagealphablending()
imagesavealpha()
and got no result
UPD:
Now I am saving image as a png file. I deleted these two rows imagealphablending($watermark_image, false); imagesavealpha($watermark_image, true); and it worked. However, the transparency of PNG is overlapping GIF. imagealphablending($image, true); didn't help. What shall I do?
GIF files are limited to 256 colours and have a single colour designated as transparent. So you can't have antialiased transparency, nor can you have much antialiasing of any kind.
I suggest saving as PNG instead.
In PHP I'm trying to process an image, that is, I'm trying to make the surrounding color transparent in a jpg file. I'm using the GD library by the way.
I can directly output the image by converting it into a png using imagecreatefromjpeg and imagepng functions. But I can't find a way to make the specified color transparent. Also, some images have lighter gray artifacts around black graphics, created during saving. Is there any way I can include those as well?
I'm kind of lost. I found some answers to make a color transparent on an image but I don't know how to first convert the image without saving it into the server and then process it.
Any ideas?
EDIT: Here's my code so far. I managed to make a specified color transparent but I can't make it detect the surrounding one yet.
Most of the time images will be closed because they'l be logos or texts, saved in the allowed image formats. So I don't think I will have a major issue with gradients but it would be great if I could manage to manipulate transparency in the surrounding gradients, if any, such as drop shadows.
Is there also any way to detect if the png/gif image is already transparent? My code paints the transparent parts into black for those files now.
$file = 'images/18.jpg';
$specs = getimagesize($file);
if($specs[2] == 1) $img = imagecreatefromgif($file); //gif
elseif($specs[2] == 2) $img = imagecreatefromjpeg($file); //jpg
elseif($specs[2] == 3) $img = imagecreatefrompng($file); //png
else exit('unsupported file type!');
$newimg = imagecreatetruecolor(imagesx($img), imagesy($img));
// create a new image with the size of the old one
imagecopy($newimg,$img,0,0,0,0,imagesx($img),imagesy($img));
// copy the old one
imagedestroy($img);
// free the memory
$white = imagecolorallocate($newimg,255,255,255);
imagecolortransparent($newimg,$white);
// make white pixels transparent
header('Content-Type: image/png');
imagepng($newimg);
imagedestroy($newimg);
// and finally output the new image
You can set the transparent color with the imagecolortransparent function.
I have an image which i am going to be using as a background image and will be pulling some other images from the database that i want to show within this image. So if i am pulling only 1 image, i want the bottom part of the background image to close after the first image, if there are multiple images then i want it close after those images are shown. The problem with not using separate images is that the borders of the images have a design format and i cannot show them separately.
Take a look at this image . The design format of the right and left borders are more complicated than that to just crop them and use them. Any suggestions if there is any dynamic image resizing thing?
Yes there is. Look at the imageXXXX functions; the ones you are particularly interested in are imagecreate, imagecreatetruecolor, imagecreatefrompng, imagecopyresampled, imagecopyresized, and imagepng (assuming you're dealing with PNG images - there's similar load / save functions for jpeg, gif, and a few other formats).
You should try using the GD extension for PHP, especially have a look at imagecopyresized(). This allows you to do some basic image conversion and manipulation very easily.
A basic example that takes two GET parameters, resizes our myImage.jpg image and outputs it as a PNG image:
<?php
// width and height
$w = $_GET['w'];
$h = $_GET['h'];
// load image
$image = imagecreatefromjpeg('myImage.jpg');
// create a new image resource for storing the resized image
$resized = imagecreatetruecolor($w, $h);
// copy the image
imagecopyresized($resized, $image, 0, 0, 0, 0, $w, $h, imagesx($image), imagesy($image));
// output the image as PNG
header('Content-type: image/png');
imagepng($resized);
Have you tried PHPThumb? I used this class often and its pretty clean and lightweight. I used it here.