I used a very simple code to resize image with PHP; but surprisingly it does not work for some images. The problem should be associated with imagecreatefromjpeg(), as it will generate a black image (which is of the background image).
$picture="test5.jpg";
$url="http://www.pokerpurist.com/uploadedImages/bettingpro/NewsImages/TN98553_Perla-Beltran.jpg";
list($width, $height) = getimagesize($url);
$new_height = $height / $width * 400;
$image_p = imagecreatetruecolor(400, $new_height);
$image = imagecreatefromjpeg($url);
imagecopyresampled($image_p, $image, 0, 0, 0, 0, 400, $new_height, $width, $height);
imagejpeg($image_p, $picture);
echo "<img src='$picture' />";
This problem happens offen, and I included an example image. What is the problem with these images leading to this problem? It seems to be a normal JPG image.
By the way, is it the simplest and most efficient way to resize image with PHP/GD2?
Your example image is a PNG, not JPEG. You probably need to put some detection code in place...
Edit: exif-imagetype or ImageMagick might be of some use.
#By the way, is it the simplest and most efficient way to resize image with PHP/GD2?
Use Asido: PHP Image Processing Solution
Asido supports the following features:
pluggable drivers for GD2 (php_gd2), MagickWand (php_magickwand),
ImageMagick extension (php_imagick) as well as ImageMagick shell
commands
"hack" drivers: workarounds for certain disabilities of a particular driver by using some of the other functionality provided
by the environment
various resize functionality: proportional resize, resize only by width or height, stretch resize, fit resize, frame resize
watermark images, including tiling watermark and automatic scaling of large watermarks
rotate images
copy images onto one another
crop images
grayscale images
convert images between different filetypes
If you can't access Asido website, you can download Asido from SourceForge.net
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 made a small function to upload images then show them on my website.
My question is now, can I change the file size of a image, on same time as I upload it?
Take facebook as example. Even large images has a size on like 65kb.
If so, witch function should I use?
Thanks,
use the imagecopyresampled function:
$source_image = imagecreatefromjpeg("youtimagejpg");
$src_w= imagesx($source_image);
$src_h= imagesy($source_image);
$dest_image = imagecreatetruecolor(100, 100); //targeted width and height
imagecopyresampled($dest_image, $source_image, 0, 0, 0, 0, 100, 100, $source_w, $source_h);
imagejpeg($dest_image,NULL,80);
//Replace null by the path if you want to save on the server, otherwise the image will be sent to the client intead.
If you want to reduce the size of the image without resizing it; use the imagejpeg function (with a low quality factor)
There are next ways to change image size:
Convert to another image format.
Save image with lossy compression (http://en.wikipedia.org/wiki/Lossy_compression)
Resample image with another width & height (http://php.net/manual/en/function.imagecopyresampled.php)
how to take image from one folder and rename and re-size the images and move to another folder?
I need to get image from one folder and rename and re-size the same image and move into another folder using php
You will most likely be using gd for resizing the images.
Here is a pretty crappy, but hopefully useful code sample. In this case, $originalName is the name given in the $_FILES array's tmp_name position. I am resizing to a width of 1200 in this case, with the height adapting according to such width. You might (and most likely will) not desire this behavior. This is just some ugly code I used in some courses I taught about 3 years ago, I don't have the newer samples in this computer so you will have to get used to the idea :)
$newDir is where the file will be located. by calling imagejpeg or imagepng and passing the filename as second argument, it means to the function that you wish to save the image in that location.
if ($type == 'image/jpeg') {
$original = imagecreatefromjpeg($originalName);
}
else {
$original = imagecreatefrompng($originalName);
}
$width = imagesx($original);
$height = imagesy($original);
//prepare for creation of image with width of 1000
$new_height = floor($height * (1200 / $width));
// create the 1200 width image
$tmp_img = imagecreatetruecolor(1200, $new_height);
// copy and resize old image into new image
imagecopyresized($tmp_img, $original, 0, 0, 0, 0,
1200, $new_height, $width, $height);
//create a random and unique name to identify (here it isn't that random ;)
$newDir = '/this/is/some/directory/and/filename.';
if ($type == 'image/jpeg') {
imagejpeg($tmp_img, $newDir."jpg");
}
else {
imagepng($tmp_img, $newDir."png");
}
Many file system functions are already built-in with PHP (e.g. rename), and you'll find most of what you need to resize images by using the GD library here.
There are libraries available in PHP for image resize.
Here are some useful links you may like.
http://www.fliquidstudios.com/2009/05/07/resizing-images-in-php-with-gd-and-imagick/
http://php.net/manual/en/book.image.php
PHP/GD - Cropping and Resizing Images
http://net.tutsplus.com/tutorials/php/image-resizing-made-easy-with-php/
Use imagick http://php.net/manual/en/imagick.resizeimage.php
If I were you I would write a PE using a diffent language (one that you might be best used to) to adjust anything of the given image then just feel free to phpexec it to do all the steps you mentioned, you can sit relax and wait for the end result. HHAHAHHA :-)
Use imagick library to resize; it's good.
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.