A Chinese man holds his son as they look at iPhones on display at an Apple store on January 7, 2019 in Beijing, China.

An improved camera system will be a major selling point for Apple's 2019 iPhone lineup, according to a research note from TF International Securities analyst Ming-Chi Kuo.

Improved cameras and picture quality could give consumers a reason to upgrade from older models as iPhone sales growth has stalled in recent years. Camera quality is frequently cited as an important factor in surveys about which features are critical to users who are deciding whether to upgrade.

Apple's iPhone lineup is expected to look a lot like its current lineup, according to Kuo's previous research. Kuo expects Apple to release a 5.8-inch iPhone (an improvement on the current iPhone XS), a 6.5-inch iPhone (like the current iPhone XS Max) and a 6.1-inch device with a lower-cost screen (which corresponds to the iPhone XR).

Here's what Kuo expects from this year's iPhone cameras:

The biggest phone — the "Max" model — will include a so-called triple camera with three lenses. The current iPhone XS Max camera has a zoom lens and a normal lens. The new model could also include a "super-wide" camera using a 12-megapixel sensor made by Sony, according to the research.

Apple's 6.1-inch phone will likely get a second camera on the back, like the current XS models. Kuo didn't specify if the 5.8-inch iPhone would have two or three rear cameras.

Kuo predicts that all three new iPhones will likely have an upgraded front camera, often called a selfie camera, with a 12-megapixel sensor.

New iPhones could adopt "black lens-coating technologies, which will make [the] lens look inconspicuous," according to the research.

"We forecast the camera upgrade will be one of the new 2H19 iPhone's major selling points," Kuo wrote in the Wednesday note.

Kuo's research is aimed at investors who buy shares in the companies that sell parts to Apple. He has a reputation for predicting Apple products before they launch.