How to display image from mysql blob in PHP (joomla)

I create a component in my joomla website. the component shows some photos (not big, only 8KB). the photos are stored in mysql blob. i can upload the photos to the joomla database but i cannot display it on the website. whatever i do it only show some encoding character or blank. I tried to create a separate page but but the result is same. Here is what i have done : mycomp is my joomla component.

admin.mycomp.php

<?php
function showDetail($option)
{
    $db = &JFactory::getDBO();
    $id = mysql_real_escape_string(JRequest::getVar('id'));
    $query = "select id,myphoto from jos_myphotos where id = ".$id;
    $db->setQuery($query);
    $rows = $db->loadObjectList();
    HTML_myphoto::showPhoto($rows,$option);
}     
?>

admin.mycomp.html.php

<?php
class HTML_myphoto
{
   ...
   function showPhoto($row,$option)
   {
      ...
      header("Content-type: image/jpeg");
      echo $row->myphoto;  //this will show some encoding character
      echo base64_decode($row->myphoto);  //this will show blank page
      //change echo with print get the same result.
      ...
   }
   ...
}

I tried to create a separate page like this : admin.mycomp.html.php

<?php
class HTML_myphoto
{
...
function showPhoto($row,$option)
{
    ...
?>
    <img src="show_image.php?myphoto=<?php echo $row->myphoto;?>" width=200 height=300>
<?php   
    ...
}
...
}

show_image.php

<?php
     $myphoto = (isset($_GET['myphoto'])) $_GET['myphoto'] : false;
     if($myphoto)
     {
         header("Content-type: image/jpeg");
         echo $myphoto;  //this will show some开发者_运维问答 encoding character
         echo base64_decode($myphoto);  //this will show blank page
         //change echo with print get the same result.
     }
?>

the result is same.

I think you have 2 options:

1. Either you make an image tag with its source in a PHP file receiving only a ID parameter and retrieving the photo's string in the DB and echoing it.

2. Or you echo directly your photo's string in your tag:

   <img src="<?php echo base64_decode($myphoto); ?>" />
   

EDIT

I just checked in an old app where I store the favicons in a DB. You don't need to base64_decode when you display your image inline (my option 2).
So FYI, this image works:

<img alt="" src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAABmJLR0QA/wD/AP+gvaeTAAAACXBIWXMAAABIAAAASABGyWs+AAAACXZwQWcAAAAQAAAAEABcxq3DAAACkElEQVQ4y42TTWyUZRSFn/e+n6W00E4l9ScSCZGODXFLIIZENyZu1ITEGBdE3ejGVQksunDlwoUrE0ICCQuomZAYF4YNNvEPlFpjiJRgKq10HDKdmVJxEOh0vu+9h0UrMSyAk9zVOffczXPRI8hdciVNTZ/X6MjLOnrkK3XTLbk64lEK5FIhaf87HyqznYKy5qsLyuUPL/D1OXzkC8U4IhhViC9o7OAnSkkKksQDVG81GR//iAvTbS7OXIQQ1p0Oc3O/YlCAAAcSQIHIEc43Z8/z6r5xfrsiBp9+ArK4FgprNye//oEMDIJDMBDU6jc4d/YXzpz5kcuzC5SGBvBkoMT257ah5FTn/4Qgpqd+InM3LEDr+j8cO/45pyrnmLk0w0uv7KV/cIDCI4GIhUAgY3h4C9W5Kma9LF//l2xpqc33301xcuJLTp+ehLiJbSNlcpxoEanAolF4okB0lRAiuVOt1cje/+AAly8tcHWhDnEDeAfXKo/FTbg7ZLdwCrDI0PAAK7fvQATkYIbN/l4jWh8pAb4BrJ/abI32301MXULKoIhE9bKxt8RKJ4D1gXpIitj+d19j6PGN7CiXQavgHYir3G5fY+tT/Wx/cgulnh6su0JYvUPodiHvAGJz32YoJC222qo1lvTH1b906NBngq06cPBjFZKkXIuNmhZbN3RlvqUTlUnt2fumsGc0NvapkJLcpeRrzF+r31R5dLd2PP+i6s3if//gcndJUqPRUKVSUbPZFCnlkpJcSWmd+dffeE/BntWJk9/eW7q/RJJSSjIzQxKBhIUcgN17dhFCxsREheXlZSStZUIghEBRFACYGRlwz3Q5FuDtt/Yx/fMFSqVB8jwnrPP/Xy7LMtwdM+Mu+2gfA7SP0igAAAAASUVORK5CYII=" style="margin-right: 5px; vertical-align: middle;" class="bbns_itemDragger">

And it is stored in my DB like this (base64 encoded):

data:image/png;base64,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

I'm sorry, did you skip some lines from show_image.php?! Cause $myphoto is just the id of the photo. You can't base64_decode an ID.