Not able to resize the logo.

I am trying to increase the size of logo but getting no success. Here is what I am sending in request:

Unirest\Request::get('https://unitag-qr-code-generation.p.mashape.com/api?data={"TYPE":"text","DATA":{"TEXT":"'.$_GET['data'].'"}}&setting={"LAYOUT":{"COLORBG":"ffffff","GRADIENT_TYPE":"HORI","COLOR1":"60000a","COLOR2":"af000f","X1":0,"Y1":0,"X2":0,"Y2":0},"EYES":{"COLOR_EHG":"dc000f","COLOR_EHD":"dc000f","COLOR_EBG":"dc000f","COLOR_EBD":"dc000f","COLOR_IHG":"dc000f","COLOR_IHD":"dc000f","COLOR_IBG":"dc000f","EYE_TYPE":"LLLeft"},"LOGO":{"L_NAME":"'.$_GET['logo'].'","L_WIDTH":150,"L_HEIGHT":150,"EXCAVATE":true},"E":"M","BODY_TYPE":7}', array(

[superProgrammer90]

hi..you know how to set background image and logo?By using the http://api.qrcode.unitag.fr/api?(objective c Xcode)