could not upload big images ?

[drascom]

hi i try to upload 5 photos per record but they are abut 6MB and 4000*3000 pix.
they uploaded to folder but browser doesnt show them also thumbnail doesnt created.
and the result is


when i choose the smaller pics there isnt problem..
why i cant see big pictures and how can i resize them before uploading ?
this is my appgini settings