Mine

or f in ${!INFILES[@]}; do    # encode still frames    ffmpeg -f image2 -loop_input -vframes $SLIDE_FRAMES -i "${INFILES[f]}" -pix_fmt yuv420p -f yuv4mpegpipe -    if $SLIDE_FADE; then        if [[ $f -lt ${#INFILES[@]} ]]; then            base_ppm="$WORK_DIR/${f}.ppm"            if ((f == (${#INFILES[@]} - 1) )); then                overlay_ppm="$WORK_DIR/0.ppm"            else                overlay_ppm="$WORK_DIR/$((f+1)).ppm"            fi            [[ $TV_STANDARD = "ntsc" ]] && fade_frames=30 || fade_frames=25            fade_incr=$(bc -l <<< "scale=2; 100 / $fade_frames")            fade_slide=0            echo            for ((i=0; i<fade_frames; i++)); do                BLEND_AMT=$(bc -l <<< "scale=2; $fade_slide * $fade_incr")                composite_cmd=(composite -blend $BLEND_AMT -depth 8 "$overlay_ppm" \                "$base_ppm" "$WORK_DIR/animenu/$(printf %06d%s $i .ppm)")                "${composite_cmd[@]}"                spin "Compositing ${overlay_ppm##*/} over ${base_ppm##*/} with -blend $BLEND_AMT"                let fade_slide=fade_slide+1            done            let first_slide=first_slide+fade_frames+1        else            echo "Running ffmpeg to encode ppms"            ffmpeg -f image2 -i "WORK_DIR/animenu/%06d.ppm" -pix_fmt yuv420p -f yuv4mpegpipe -            FFPID=?!            wait $FFPID            rm -f "WORK_DIR/animenu/*.ppm"        fi    fidone >&3