From 70fe0f46f6c0af9db89f49076f97d2344813f520 Mon Sep 17 00:00:00 2001
From: Lawrence Lee <45837045+Lawrence37@users.noreply.github.com>
Date: Sat, 27 Aug 2022 16:38:03 -0700
Subject: [PATCH] Use hard-coded levels for Canon raws

Closes #6559.
---
 rtengine/dcraw.cc | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/rtengine/dcraw.cc b/rtengine/dcraw.cc
index e4dbcbf94..bb8cafaf0 100644
--- a/rtengine/dcraw.cc
+++ b/rtengine/dcraw.cc
@@ -9082,8 +9082,21 @@ void CLASS adobe_coeff (const char *make, const char *model)
 
   for (i=0; i < sizeof table / sizeof *table; i++)
     if (!strncmp (name, table[i].prefix, strlen(table[i].prefix))) {
-      if (RT_blacklevel_from_constant == ThreeValBool::T && table[i].black)   black   = (ushort) table[i].black;
-      if (RT_whitelevel_from_constant == ThreeValBool::T && table[i].maximum) maximum = (ushort) table[i].maximum;
+      if (RT_blacklevel_from_constant == ThreeValBool::T && table[i].black) {
+        if (RT_canon_levels_data.black_ok) {
+          unsigned c;
+          FORC4 RT_canon_levels_data.cblack[c] = (ushort) table[i].black;
+        } else {
+          black = (ushort) table[i].black;
+        }
+      }
+      if (RT_whitelevel_from_constant == ThreeValBool::T && table[i].maximum) {
+        if (RT_canon_levels_data.white_ok) {
+          RT_canon_levels_data.white = (ushort) table[i].maximum;
+        } else {
+          maximum = (ushort) table[i].maximum;
+        }
+      }
       if (RT_matrix_from_constant == ThreeValBool::T && table[i].trans[0]) {
 	for (raw_color = j=0; j < 12; j++)
 	  ((double *)cam_xyz)[j] = table[i].trans[j] / 10000.0;