headers and images

TimC

Hi,

I'm having problems with displaying raw image data direct from a database. The images are stored in a BLOB in the database, when I try to retrieve them and print them to screen, it only prints out a load of ascii.

Now I read somewhere that I need to alter the headers before I try to output the image, but this gives me a headers already sent error. For the time being, I've commented this out. I also read something about obj_flush and obj_start, so started trying to use those, but so far, no joy. Could anyone advise me of the right method to display raw image data please?

Here is an excerpt of my code:

<?php
	   $sql = "SELECT * from Images";
	   $resultset=@mysql_query($sql) or die(mysql_error()); 


   while ($row = mysql_fetch_array($resultset)){
	  		  //ob_end_flush();
	  //ob_start();    
      echo "<tr>";
	  echo "<td> $row[0] </td>";
	  $bytes = $row[Image];  

	  echo "<td>";
	  //ob_end_flush();
	  //ob_start();   
	  //header("Content-type: image/jpeg");  


	  print "$bytes";
	  echo "</td>";  
	  echo "</tr>";  
   }   
?>

greensweater

You can't output a graphic file in the middle of outputting an HTML file. Headers are already sent because you're already outputting HTML in the form of echo "<tr>" etc. The browser must receive a header with each page element. i.e., when you hit a web page, the browser first gets the HTML, then while rendering the page it must go fetch elements (such as IMG, LINK, EMBED)

It may be easier to visualize this as a separate PHP file, but you could do it inline as well:

<?php

// beginning of the script, capture output
ob_start();

// initialize
$db = mysql_connect('localhost','user','pass');
mysql_db_select('images_table');

// handle image requests
if (isset($_GET['file_id']))
{
  $id = mysql_real_escape_string($_GET['file_id']);
  $result = mysql_query("select blob_data from my_table where id = $id");
  if ($blob = mysql_result($result,0,0))
  {
    header("Content-type: image/jpg"); // (or whatever it is)
    echo $row['blob_data'];
    exit;
  }
}

// ... now do something else ...
ob_end_flush(); // output whatever you may have added before this part
echo "<table><tr><td>";
echo "<img src='".$_SERVER['PHP_SELF']."?file_id=123' />";
echo "</td></tr></table>";