diff --git a/third_party/libopenjpeg20/0004-j2k_read_mcc.patch b/third_party/libopenjpeg20/0004-j2k_read_mcc.patch
new file mode 100644
index 0000000..39c847d
--- /dev/null
+++ b/third_party/libopenjpeg20/0004-j2k_read_mcc.patch
@@ -0,0 +1,31 @@
+diff --git a/third_party/libopenjpeg20/j2k.c b/third_party/libopenjpeg20/j2k.c
+index 849d0b4..b20f219 100644
+--- a/third_party/libopenjpeg20/j2k.c
++++ b/third_party/libopenjpeg20/j2k.c
+@@ -5341,6 +5341,7 @@ static OPJ_BOOL opj_j2k_read_mcc (     opj_j2k_t *p_j2k,
+         OPJ_UINT32 l_nb_collections;
+         OPJ_UINT32 l_nb_comps;
+         OPJ_UINT32 l_nb_bytes_by_comp;
++        OPJ_BOOL new_mcc = OPJ_FALSE;
+ 
+         /* preconditions */
+         assert(p_header_data != 00);
+@@ -5402,6 +5403,7 @@ static OPJ_BOOL opj_j2k_read_mcc (     opj_j2k_t *p_j2k,
+                         memset(l_mcc_record,0,(l_tcp->m_nb_max_mcc_records-l_tcp->m_nb_mcc_records) * sizeof(opj_simple_mcc_decorrelation_data_t));
+                 }
+                 l_mcc_record = l_tcp->m_mcc_records + l_tcp->m_nb_mcc_records;
++                new_mcc = OPJ_TRUE;
+         }
+         l_mcc_record->m_index = l_indix;
+ 
+@@ -5537,7 +5539,9 @@ static OPJ_BOOL opj_j2k_read_mcc (     opj_j2k_t *p_j2k,
+                 return OPJ_FALSE;
+         }
+ 
+-        ++l_tcp->m_nb_mcc_records;
++        if (new_mcc) {
++                ++l_tcp->m_nb_mcc_records;
++        }
+ 
+         return OPJ_TRUE;
+ }
diff --git a/third_party/libopenjpeg20/README.pdfium b/third_party/libopenjpeg20/README.pdfium
index bdb2f62..728c0d8 100644
--- a/third_party/libopenjpeg20/README.pdfium
+++ b/third_party/libopenjpeg20/README.pdfium
@@ -13,4 +13,5 @@
 0001-image-data.patch: Fix a crashier in opj_j2k_update_image_data().
 0002-packet-iterator.patch: Fix integer overflow in opj_pi_create_decode().
 0003-dwt-decode.patch: Check array bounds for opj_dwt_decode_1() and friends.
+0004-j2k_read_mcc.patch: Move incrementing of l_tcp->m_nb_mcc_records to the right place.
 TODO(thestig): List all the other patches.
diff --git a/third_party/libopenjpeg20/j2k.c b/third_party/libopenjpeg20/j2k.c
index 849d0b4..b20f219 100644
--- a/third_party/libopenjpeg20/j2k.c
+++ b/third_party/libopenjpeg20/j2k.c
@@ -5341,6 +5341,7 @@
         OPJ_UINT32 l_nb_collections;
         OPJ_UINT32 l_nb_comps;
         OPJ_UINT32 l_nb_bytes_by_comp;
+        OPJ_BOOL new_mcc = OPJ_FALSE;
 
         /* preconditions */
         assert(p_header_data != 00);
@@ -5402,6 +5403,7 @@
                         memset(l_mcc_record,0,(l_tcp->m_nb_max_mcc_records-l_tcp->m_nb_mcc_records) * sizeof(opj_simple_mcc_decorrelation_data_t));
                 }
                 l_mcc_record = l_tcp->m_mcc_records + l_tcp->m_nb_mcc_records;
+                new_mcc = OPJ_TRUE;
         }
         l_mcc_record->m_index = l_indix;
 
@@ -5537,7 +5539,9 @@
                 return OPJ_FALSE;
         }
 
-        ++l_tcp->m_nb_mcc_records;
+        if (new_mcc) {
+                ++l_tcp->m_nb_mcc_records;
+        }
 
         return OPJ_TRUE;
 }