Many TVs will not show images that are outside some size or such. For example, few TVs till recently could show jpeg files from my canon t5i. I would have to resize them to be suitable on a 1080p TV.
My t5i can produce 8MP images at 3456 x 2304. This is HUGE and TVs often have limited RAM and may just skip those.
Try a set of images set to 1080p size (1920 x 1080).
My Aunt lives in Scotland and she has a Toshiba TV model 37XV55D, we're want to send her Lexar USB memory stick of our 11+ baby girl, but not all the photos are showing. All photos are in jpg