To generate 100 images, containing numbers 0 to 100:
for f in `seq 0 100` ; do convert -size 25x25 xc:transparent -font /usr/share/fonts/truetype/ttf-dejavu/DejaVuSansMono-Bold.ttf \ -fill $COLOR -pointsize 19 -draw \"text 1,20 '$f'\" res/drawable/notify_$f.png done

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