XnView Software

As you know, the number of map tiles is usually very large, making it difficult to handle manually, which is why the 'Join images' function is needed. The tiles I need to stitch are numbered starting from the bottom left corner, increasing upwards and to the right. This requires you to provide a Right/Down alignment option. I am providing you with level 1 tiles to facilitate the addition of this alignment option.

I tried using XnView MP, PIL, and OpenCV to stitch together the tile map I needed. I found that for levels 7 and 8 (32768*65536, 65536*131072) output PNGs, there is a strange phenomenon in the preview in XnView:

At 100% zoom, the bottom 1/3 of the content cannot be displayed normally, and the further down you move, the greener it gets. This only happens at 100% zoom, not at 150% or 50%.