How to convert byte array to image in php?

Question

I want to convert the byte array from a webservice to image. The webservice response array looks like the following but I could not figure out how to render this array back to an image. Please help me

'MemberImage' => 
    array (size=151745)
      0 => int 255
      1 => int 216
      2 => int 255
      3 => int 224
      4 => int 0
      5 => int 16
      6 => int 74
      7 => int 70
      8 => int 73
      9 => int 70
      10 => int 0
      11 => int 1
      12 => int 1
      13 => int 1
      14 => int 0
      15 => int 72
      16 => int 0
      17 => int 72
      18 => int 0
      19 => int 0
      20 => int 255 ...

Federkun · Accepted Answer · 2015-06-12 09:46:34Z

3

Use pack to convert data into binary string, es:

$data = implode('', array_map(function($e) {
    return pack("C*", $e);
}, $MemberImage));

// header here
// ...

// body
echo $data;

answered Jun 12, 2015 at 9:46

Federkun

37.2k8 gold badges82 silver badges93 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Gokul Basnet Over a year ago

I tried this code but image is not generate instead its generates the output like this,��JFIFHH��Photoshop 3.08BIM�HH8BIM� 8BIM�H/fflff/ff��2Z5-8BIM�p��

Sherif · Accepted Answer · 2015-06-12 10:22:49Z

2

If you want to convert that array to an actual byte array (i.e. a binary string in PHP) you could use the following function...

function arrayToBinaryString(Array $arr) {
    $str = "";
    foreach($arr as $elm) {
        $str .= chr((int) $elm);
    }
    return $str;
}

You could also use pack instead of the above function to do the same thing like so...

call_user_func_array('pack', array_merge(['C*'], $arr));

or in PHP 5.6+

pack('C*', ...$arr);

With that you could then - in theory - use the binary string as an image. So, for example, assuming you want to output the raw image data, and that the image is say a PNG, you would do something like the following, in conjunction with the above code...

header('Content-type: image/png');
echo arrayToBinaryString($myArray);

Just be sure to edit the Content-type header with whatever type the actual image is. If you don't know you could use something like getimagesize on the binary string to extract the MIME type from the image data.

$tmpFile = tempnam("/tmp");
$image = arrayToBinaryString($myArray);
file_put_conetnts($tmpFile, $image);
$imageData = getimagesize($tmpFile);
header("Content-type: {$imageData['mime']}");
echo $image;
unlink($tmpFile);

edited Jun 12, 2015 at 10:22

answered Jun 12, 2015 at 9:51

Sherif

12k3 gold badges35 silver badges58 bronze badges

2 Comments

Gokul Basnet Over a year ago

when i run this it shows "Call to undefined function tmpnam()"

Sherif Over a year ago

@GokulBasnet Yea, the function is called tempnam, that was a typo. I'll correct it.

Collectives™ on Stack Overflow

How to convert byte array to image in php?

2 Answers 2

1 Comment

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related