print BASE64 coded image into a FPDF document

问题

I've some as base64 stored images in a database. Is it possible to print those data directly in a PDF document, using FPDF?

Data sctructure of the image

data:image/png;base64,iVBORw0KGgoAAAANSUhEUg7AAAfQAAACWCAYAAAAonXpvAAAfgUlEQVR4Ae2dC9BuVVnHuSN3QaBENA9h5A2IcJxMj8hUkymoQDfClIkmrQZr1EydMqapnKRMc8JmHLBBHadJJaV0lKQDZCmCQiqQ2KERUFARDhcFDpx /33W tznPe/ 3ttaa9/ a2Z9/32Xvt5nvVbl2evtdfee9dtS27bt4mACJmACJm8ACJtBvArv123xbbwImYAImYAImIAJ26K4HJmACJmACJjAAAnboAyhEZ8EETMAETMAE7NBdB0zABEzABExgAATs0AdQiM6CCZiACZiACdihuw6YgAmYgAmYwAAI2KEPoBCdBRMwARMwAROwQ3cdMAETMAETMIEBELBDH0AhOgsmYAImYAImYIfuOmACJm

I think $pdf->imagepng() should be the right function in FPDF.

回答1:

While the comments suggested a TCPDF solution, I did want to state that there is a way to do this entirely with FPDF. The thought process is like this:

Strip data:image/png;base64, from the URI using explode
Decode the URI with base64_decode
Save the decoded data to a PNG file with file_put_contents
Generate a PDF and add the PNG file with Image
Delete the PNG file with unlink

Always remember to error check. If the image fails to save to the server you obviously do not want to continue execution. Make sure to always strictly check if the functions return false!

Here is my solution. I used a tiny image for a small URI in this example.

const TEMPIMGLOC = 'tempimg.png';

$dataURI    = "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAPCAMAAADarb8dAAAABlBMVEUAAADtHCTeKUOwAAAAF0lEQVR4AWOgAWBE4zISkMbDZQRyaQkABl4ADHmgWUYAAAAASUVORK5CYII=";
$dataPieces = explode(',',$dataURI);
$encodedImg = $dataPieces[1];
$decodedImg = base64_decode($encodedImg);

//  Check if image was properly decoded
if( $decodedImg!==false )
{
    //  Save image to a temporary location
    if( file_put_contents(TEMPIMGLOC,$decodedImg)!==false )
    {
        //  Open new PDF document and print image
        $pdf = new FPDF();
        $pdf->AddPage();
        $pdf->Image(TEMPIMGLOC);
        $pdf->Output();

        //  Delete image from server
        unlink(TEMPIMGLOC);
    }
}

回答2:

I'know this is an old topic, but there is a easier way of solving this problem. Just try this simple steps:

Strip data:image/png;base64 from URI using explode
Concatenate data://text/plain;base64, with what is left from the stripped URI
Use the result string(base64) as argument of FPDF Image()

Example:

$dataURI= "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAPCAMAAADarb8dAAAABlBMVEUAAADtHCTeKUOwAAAAF0lEQVR4AWOgAWBE4zISkMbDZQRyaQkABl4ADHmgWUYAAAAASUVORK5CYII=";

$img = explode(',',$logo,2);
$pic = 'data://text/plain;base64,'. $img;

$pdf = new FPDF();
$pdf->AddPage();
$pdf->Image($pic, 10,30,0,0,'png');
$pdf->Output();

Remember of choose the correct image type on Image() function.

回答3:

To ensure the images work with FPDF and to avoid errors, here is a modified version of @pedro-soares' code:

function getImage($dataURI){
  $img = explode(',',$dataURI,2);
  $pic = 'data://text/plain;base64,'.$img[1];
  $type = explode("/", explode(':', substr($dataURI, 0, strpos($dataURI, ';')))[1])[1]; // get the image type
  if ($type=="png"||$type=="jpeg"||$type=="gif") return array($pic, $type);
  return false;
}

Because FPDF only allows these three file types, it is important to check that it is valid. To use:

$pic = getImage($Base64StringGoesHere);
if ($pic!==false) $pdf->Image($pic[0], 10,30,0,0, $pic[1]);

回答4:

To add a bit more to Mari M answer, I just added few lines to work with any types of images. (as for me FPDF complains if the image is jpeg and I try to load tempimg.png)

$this->tempImgLoc = 'tempimg';    // Here I just remove the file extension
$dataPieces = explode(',',$dataURI);
$encodedImg = $dataPieces[1];
$decodedImg = base64_decode($encodedImg);

// extract the image type from data:image/png;base64
$extension = explode('/', $dataPieces[0]);
$extension = explode(';', $extension[1]);

$this->tempImgLoc .= '.' . $extension[0];

I am sure there is a better way to do that with regular expression, but to be honest, regexp is not my cup of tea...

回答5:

Ok, I wasted half day making test with this issue. I have to tell that this solution is for print images from db row, directly, without stored them on temp files.

I´m going to write some points to consider:

I´m using blob type on the DB to store human signature for print on pdf document
I´m sending the signature to store to the db by post method, from a canvas node.
When I print the string from the db blob, it´s come without the plus character "+" that don´t let me to print correctly the signature. To solve this issue, I make a "str_replace" to remove the blank spaces and insert the plus character.

Then the only thing that you have to do is:

$pdf->Image(str_replace(' ','+',$dbRow['blobImage']),160,150,20,10,'png');

If you need , like me, print several images from the db, you have to see if them come or not, because if the image come empty, you´ll have an error.

I just add this to the last code:

if( $dbRow['blobImage'] ){
                 $pdf->Image(str_replace(' ','+',$dbRow['blobImage']),160,150,20,10,'png');
            }

NOTE:

160 -> X position of the image
150 -> Y position of the image
20 -> X Scale of the image
10 -> Y Scale of the image
'png' -> The base format of my Base64 Image Type.

回答6:

New solution with imagecreatefromstring() Summer 2019

delete temporary .png if exist
create temporary .png file
use $pdf->Image (fpdf)

My Api returns me a Datamatrix of 1234 as Byte Array. The folowing code shows you how to use that Byte Array as Png in Fpdf.

My $response = "iVBORw0KGgoAAAANSUhEUgAAAAoAAAAKCAYAAACNMs+9AAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsMAAA7DAcdvqGQAAABJSURBVChTjYwBCgAgCAP9/6dNreVUgg7Gps3EUOfD5Q4Au6YdAGcH8ygyVKrFnhmbc9FL7qRxWRxEkXWW4Q691UsGpZPzt7dEFyY47RMW+x2LAAAAAElFTkSuQmCC"

$filename = '/lk_Reptool/printing/tmp/tmppng.png';

if (file_exists($filename)) {
    unlink($filename);
}
$response = file_get_contents('https://myapi.com/TwoDCode/GetDatamatrixAsPngByteArray?datamatrixText=' . $RepID . '&pixelSize=100');
$response = base64_decode($response);
$img = imagecreatefromstring($response);
imagepng($img, $filename);

code for pdf

$pdf = new PDF('P', 'mm', 'A4');
$pdf->AddPage();
$pdf->Image('/lk_Reptool/printing/tmp/tmppng.png', 180, 20, 10, 10);

来源：https://stackoverflow.com/questions/18484632/print-base64-coded-image-into-a-fpdf-document

标签

php

base64

fpdf