将varbinary转换为可显示的图像

I have a string with has the contents of a varbinary (from an MSSQL database) that refers to a picture. I have pasted it here because its so long - https://pastebin.com/isEPT4Vw

So im now trying to display the image using PHP

I encode it to base 64 and then try to display it on the page:

$basePic = base64_encode($photo);

header("Content-type: image/gif");
echo '<img src="data:image/gif;base64,' . $basePic . '" />';

All im getting is a black image.

I have tried to echo the base 64 image and put it in an online base 64 to image converter which gave me the same black image. Is it just the image thats corrupt? or am i doing something else wrong, Thanks