--- agaconv	2020-05-11 05:05:26 +0200
+++ dh0:agaconv	2021-03-23 02:24:04 +0100
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 
 ##########################################################################
 # AGAConv - CDXL video converter for Commodore-Amiga computers           #
@@ -146,8 +146,10 @@
 function log2 {
     local val=$1
     local x=0
-    for (( y=$val-1 ; $y > 0; y >>= 1 )) ; do
+    local y=$val
+    while [ $y -gt 1 ] ; do
         let x=$x+1
+        let y/=2
     done
     echo $x
 }

--- agaconv.bak	2021-04-03 22:28:32 +0200
+++ agaconv	2021-04-05 20:46:07 +0200
@@ -885,11 +885,11 @@
         ;;
     aga8|aga7|aga6|aga5|aga4|aga3)
         planes=$(expr substr $colorMode 4 1)
-        maxColors=$((2**$planes)) # number of planes to the power of 2
+        maxColors=$((1<<$planes)) # number of planes to the power of 2
         ;;
     ocs5|ocs4|ocs3)
         planes=$(expr substr $colorMode 4 1)
-        maxColors=$((2**$planes)) # number of planes to the power of 2
+        maxColors=$((1<<$planes)) # number of planes to the power of 2
         agaconvEncodeColorOption="--color-bits 12"
         ;;
     normal)
@@ -966,14 +966,14 @@
  
     case $hcQuant in
         wu)
-            if [[ $hamMode=="yes" ]]; then
+            if [[ $hamMode == "yes" ]]; then
                 hcQuantOption=quant_wu
             else
                 hcQuantOption=
             fi
             ;;
         neuquant)
-            if [[ $hamMode=="yes" ]]; then
+            if [[ $hamMode == "yes" ]]; then
                 # for HAM neu_quant is default (and not specified on command line)
                 hcQuantOption=
             else