Comparison between the SNR+DIG neural network classification and the one with a traditional method from the literature for a section of the observed M33 field. On the left is the SNR+DIG contribution map as predicted by the network. Colours tending to red show a higher probability of SNR or DIG, while those tending to green a lower one. On the right, a map coloured based on the [S II]λ6716, 6731/Hα ratio. A higher value of the ratio suggests brighter [S II] emission with respect to Hα. The yellow star symbols mark O type ionising stars from Williams et al. (2021), selected based on flux and colour. Instead, the light blue ones mark Wolf-Rayet stars (Neugent & Massey 2011). In both images, the blue circles show the Ciardullo et al. (2004) PNe, while the green circles mark the Lee & Lee (2014) and Long et al. (2018) SNRs. The pink contours mark the points with a predicted SNR+DIG contribution of 0.6.