eBay API returns low resolution thumbnails instead of the image uploaded by seller

Question

When utilizing eBay's API, the listings show using the low res thumbnail pictures, rather than the high res version that the seller uploaded. What must I alter in the code to fix this? I've looked at solutions on eBays API forum, but it doesn't seem to be relevant to the code used in the tutorial.

Javascript code:

<div id="api"></div>

<script>
function _cb_findItemsByKeywords(root)
{
  var items = root.findItemsByKeywordsResponse[0].searchResult[0].item || [];
  var html = [];
  html.push('<table width="100%" border="0" cellspacing="0" cellpadding="3"><tbody>');

  for (var i = 0; i < items.length; ++i)  
  {
    var item     = items[i];
    var title    = item.title;
    var pic      = item.galleryURL;
    var viewitem = item.viewItemURL;

    if (null != title && null != viewitem)
    {
      html.push(
        '<tr id="api_microposts"><td>'
         + '<img src="' + pic + '" border="0" width="190">' + '<a href="' + viewitem + '" target="_blank">' + title + 
         '</a></td></tr>');
    }
  }
  html.push('</tbody></table>');
  document.getElementById("api").innerHTML = html.join("");
}


// Create a JavaScript array of the item filters you want to use in your request
var filterarray = [
  {"name":"MaxPrice",
   "value":"500",
   "paramName":"Currency",
   "paramValue":"USD"},
   {"name":"MinPrice",
   "value":"200",
   "paramName":"Currency",
   "paramValue":"USD"},
  {"name":"FreeShippingOnly",
   "value":"true",
   "paramName":"",
   "paramValue":""},
  {"name":"ListingType",
   "value":["FixedPrice"],
   "paramName":"",
   "paramValue":""},
  ];

// Define global variable for the URL filter
var urlfilter = "";


// Generates an indexed URL snippet from the array of item filters
function  buildURLArray() {
  // Iterate through each filter in the array
  for(var i=0; i<filterarray.length; i++) {
    //Index each item filter in filterarray
    var itemfilter = filterarray[i];
    // Iterate through each parameter in each item filter
    for(var index in itemfilter) {
      // Check to see if the parameter has a value (some don't)
      if (itemfilter[index] !== "") {
        if (itemfilter[index] instanceof Array) {
          for(var r=0; r<itemfilter[index].length; r++) {
          var value = itemfilter[index][r];
          urlfilter += "&itemFilter\(" + i + "\)." + index + "\(" + r + "\)=" + value ;
          }
        }
        else {
          urlfilter += "&itemFilter\(" + i + "\)." + index + "=" + itemfilter[index];
        }
      }
    }
  }
}  // End buildURLArray() function

// Execute the function to build the URL filter
buildURLArray(filterarray);




</script>


<!--
Use the value of your appid for the appid parameter below.
-->
<script src=http://svcs.ebay.com/services/search/FindingService/v1?SECURITY-APPNAME=*APPNAME*&OPERATION-NAME=findItemsByKeywords&SERVICE-VERSION=1.0.0&RESPONSE-DATA-FORMAT=JSON&callback=_cb_findItemsByKeywords&REST-PAYLOAD&keywords=iphone%205%2016gb%20unlocked&paginationInput.entriesPerPage=3>
</script>

Answer 1

I struggled with this for a long time too. Make these changes:

1. Replace item.galleryURL; with item.pictureURLSuperSize;
2. Add &outputSelector=PictureURLSuperSize right after &paginationInput.entriesPerPage=3

That should do the trick. Make sure to use the same capitalization structure.
I wrote a longer blog post about this with more examples here

Answer 2

By default the Finding API returns a 140px thumbnail. You will have to specify an outputSelector in your API call in order to retrieve a larger thumbnail (400px or 800px). Adding either outputSelector=PictureURLLarge or outputSelector=PictureURLSuperSize to the call should make it return a URL for a larger image.