Can I base64 encode an image that I created on the fly, without first saving it to disk? As far as I know, base64_encode() only accepts strings, and I couldn't find a way to retrive image source object as string without first saving it, and load it with file_get_contents()
GD doesn't provide a method to return an output image as text, but you can fake it with the output buffering functions:
ob_start();
imagejpeg($handle); // no second parameter, will do output instead of writing to file
$img = ob_get_clean();
echo base64_encode($img);
Related
How can I get a base64 string from an image resource in PHP? Note however, I made the image on the fly, so no URL exists.
Here is what I've tried, but it doesn't work:
echo 'data:image/png;base64,'.base64_encode($img);
This gives an error:
Warning: base64_encode() expects parameter 1 to be string, resource given
There's no way to tell GD to return your image as a binary string, unfortunately. GD only supports writing to a file or to the screen. What we can do though is use output buffering to capture its output and then put it in a string.
ob_start();
imagepng($img);
$image = ob_get_clean();
echo 'data:image/png;base64,'.base64_encode($image);
I want to open a image url, convert it to an image, so I can use imagecopymerge() on it, then convert that to base64.
I was able to view the image data using file_get_contents, but I'm not sure how to combine that with imagecreatefromstring, imagecopymerge, and base64_encode.
The way I finally did it was to use
$img=imagecreatefrompng('url');
ob_start();
imagepng($img);
$imgString=ob_get_clean();
$imgBase64=base64_encode($imgString);
I found out that I can't convert an image to a string, and have to use the buffer.
I have a php script that generates an image then outputs the image as a png.
$img = imagecreatetruecolor($graphWidth,$graphHeight);
...
*drawing routines*
...
header("Content-type: image/png");
imagepng($img);
What I now need is to get the php script to base64 encode the image data and output that string (so I can eventually pass that encoded data to a java script which decodes and adds this image to a generated pdf).
I have tried many times to get it working myself using other stackoverflow posts/answers etc. but I don't understand enough about this technology to have gotten it to work.
Can someone help me with this please?
Thanks in advance,
Chris
The reason this doesn't work is because the image in $img is a resource, not an actual PNG image. When you call imagepng(), it outputs the image.
What I would do is create an output buffer, and base-64 encode it.
ob_start();
imagepng($img);
$buffer = ob_get_clean();
ob_end_clean();
echo base64_encode($buffer);
Don't forget to change your Content-Type header, as this is no longer image/png.
I am getting a base64 encoded JPEG string via a POST request to my web service.
I want to decode it and save it in the filesystem.
How can I achieve this using PHP 5.3.
I am able to successfully decode the data using the base64_decode function.
How can I save this decoded string as a JPEG image in the server?
Thanks in advance.
If you are sure the image will always be jpg then you can simply use: file_put_contents();
<?php
$decoded=base64_decode($encodedString);
file_put_contents('newImage.JPG',$decoded);
//leave it to you to randomize the filename.
?>
Replacing the blank spaces with + signs is required if the data is derived from canvas.toDataURL() function.
$encodedString = str_replace(' ','+',$encodedString);
See this question
It helped a lot in my case.
I have a gd image reference (I've already manipulated the image how I want to), and now I want to store the image. Instead of saving it directly to a file, is there a way I can get the binary data, that way I can convert it to base64 then save the base64 string. The only option I've been able to find is imagejpeg($image), but that either saves it as a file or prints it directly to the browser.
You can output to the buffer, and then capture it in this way.
ob_start();
imagejpeg($image);
$data = ob_get_contents();
ob_end_clean();