How to force ImageMagick to produce single output image?

I'm trying to开发者_运维技巧 convert tiff file to jpg in bash script, although I get 3 jpeg files (good, average and poor quality, I assume, same image) instead of one.

Here's an example of command:

convert -resize 200x200 -quality 90 "$CURRENT_DIR/$i" "$OP/$WITHOUT_EXT.thumb.jpg"

I've also tried without resize and quality params, but result is still the same.

Is it possible to get a single output file? Thank you!

---

try to add [] or [0] at end of source file:

convert -resize 200x200 -quality 90 "$CURRENT_DIR/${i}[0]" "$OP/$WITHOUT_EXT.thumb.jpg"