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.
Related
I'm trying to draw a partially transparent PNG image on another image I created in my script, but it behaves really strange. I'm using imagecopymerge because I want to use different opacity values, but when I do this, the output looks like this:
There must be some problem when processing the image. the yellow parts aren't even visible in the png file. Everything but the black parts are transparent.
I saved the image in photoshop and it looks ok when I just use imagecopy or something.
here are the relevant parts of the script:
$imgLogoBg = file_exists($logoBgImgFile)?imagecreatefrompng($logoBgImgFile):null;
$image = imagecreatetruecolor(imagesx($imgBase), imagesy($imgBase));
imagefill($image, 0,0, imagecolorat($imgBase,0,0));
imagecopymerge( $image, $imgLogoBg,
0,0,
0,0, imagesx($imgLogoBg), imagesy($imgLogoBg),50);
imagepng($image);
I can't figure out what the problem is. when I use another image the result is similar.
I had troubles resizing a PNG and maintaining small file sizes. Solution found here.
When resizing the PNG, however, I ran into problems regarding image quality. As far as I could see, GD uses indexed 8-bit-color palette which distorts text and colors get lost, see:
Original Image
Resized Image with solution given above
Resized Image with a tweak²
²The idea for the tweak I found here in stackoverflow: Create truecolor-image, resize it, and copy it to a new image, so the palette is determined based on the resampled result and the image quality is better as you can see in the image above.
// create new image
$newImageTmp = imagecreatetruecolor($newwidth,$newheight);
// we create a temporary truecolor image
// do the image resizing by copying from the original into $newImageTmp image
imagecopyresampled($newImageTmp,$src,0,0,0,0,$newwidth,$newheight,$width,$height);
// create output image
$newImage = imagecreate($newwidth,$newheight);
// copy resized truecolor image onto index-color image
imagecopy($newImage,$newImageTmp,0,0,0,0,$newwidth,$newheight);
// write image to buffer and save in variable
ob_start(); // stdout --> buffer
imagepng($newImage,NULL,6);
$newImageToSave = ob_get_contents(); // store stdout in $newImageToSave
ob_end_clean(); // clear buffer
// remove images from php buffer
imagedestroy($src);
imagedestroy($newImageTmp);
imagedestroy($newImage);
Problem: None of both results are satisfactory.
I am quite sure that there must be a way to 1. determine the color palette, and 2. maintain most of the image's colors, so that 3. the PNG looks similar to the original and has an acceptable file size.
Now, I only see going for JPG instead of PNG. But if you know a solution, it would greatly be appreciated if you let me/us know.
Thank you!
All you need is to replace
$newImage = imagecreate($newwidth,$newheight);
With
$newImage = imagecreatetruecolor($newwidth, $newheight);
Output $maxImgWidth = 200;
PHP's fork of GD doesn't have usable palette generation, so you only get PNG32 with vanialla libpng compression.
For small PNG8 with palette use pngquant, e.g. http://pngquant.org/php.html
And then compress it further with advpng or zopfli-png.
I have lots of jpeg images that are oversized (height, width), all with different sizes and different aspect ratios.
I'm showing them from a database like this:
<img src="<?php echo $img1; ?>" width="300" height="400">
What I'd like to have is some kind of php function to display a cropped version of the image like this:
cropjpeg('$img1');
For example, if the image is 600 W, 700 H, have php or GD show a cropped version around 300 W, 400 H starting from the top left hand of the image.
Some caveats:
I can't use CSS to do faux cropping. If you download this cropped image, it needs to be just that, the smaller cropped version.
I don't really want to create and save a new image, so I guess I need this to work "on the fly"
I tried imagecreatefromjpeg and imagejpeg, but it seems as though header('Content-Type: image/jpeg'); is not the right answer since there is more on the html page than just this 1 image
There is a lot of traffic on the site, so it has to tread lightly
Here's the best I found so far, but it uses the header('Content-Type: image/jpeg');
<?php
function cropjpeg($img, $x, $y, $width, $height,$grade=5)
{
// Create image instances
$src = imagecreatefromjpeg($img);
$dest = imagecreatetruecolor(400, 300);
// Copy
imagecopy($dest, $src, 0, 0, 20, 13, 400, 300);
// Output and free from memory
header('Content-Type: image/jpeg');
imagejpeg($dest);
imagedestroy($dest);
imagedestroy($src);
}
cropjpeg('images/bikini.jpg');
?>
Any ideas?
You cannot crop an image in the actual html page as it needs to be processed, that's if you don't want to save it on disk.
You can dump the crop script in a single PHP file with headers and call from HTML the script with path eg:
<img src="http://www.example.org/crop.php?i=bikini.jpg&x=13&y=20&w=400&h=300" alt="" />
and in script you can use
<?php
header('Content-Type: image/jpeg');
function cropjpeg($img, $x, $y, $width, $height,$grade=5) {
//......................
imagecopy($dest, $src, 0, 0, $x, $y, $width, $height);
//......................
}
cropjpeg('images/'.$_GET['i'], (int)$_GET['x'], (int)$_GET['y'], (int)$_GET['w'], (int)$_GET['h']);
?>
You should consider the aspect ratio, and search for a better crop script, you don't have to reinvent the wheel.
Use mod_rewrite to send requests for the relevant image file paths to a PHP script, which does the cropping and sends the image data back in response. It looks like a normal image tag on the page, but the images are really being served by your separate script.
The only issue is that you simultaneously don't want to save the cropped files, but have a lot of traffic so want to "tread lightly". You can't have both ways. If you don't want to re-crop the images on every request, you'll need to save the cropped versions so you can re-serve them on future requests.
Here is a page with a very complete tutorial with everything you need to do this using ajax included
crop with jquery and php
[http://www.skillcorp.com.ve][2]
[2]: http://www.skillcorp.com.ve here also more info relational
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 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