I used "generate-n6-model.sh" script to generate "network_data.hex" file as in the repo. However, it didn't match the original file. As a result, when I programed it to dev board "STM32N6570-DK", the app only shows images, and didn't detect persons. On the other hand, if I programed the original "network_data.hex" to the board, the app did detect persons. It seemed the "st_yolo_x_nano_480_1.0_0.25_3_st_int8.tflite" file didn't match the generated hex file.
