diff --git a/source/Tier2/finalize_packet.m b/source/Tier2/finalize_packet.m
index 5c3ea45..5a6ca35 100644
--- a/source/Tier2/finalize_packet.m
+++ b/source/Tier2/finalize_packet.m
@@ -5,6 +5,7 @@
 total_bytes_of_packet_header = 0;
 
 codingStyle = get_coding_Styles(main_header, hTile.header);
+c_NL = zeros(1, main_header.SIZ.Csiz);
 for c = 0:main_header.SIZ.Csiz - 1
     [codingStyle, codingStyleComponent] = get_coding_Styles(main_header, hTile.header, c);
     c_NL(c + M_OFFSET) = codingStyleComponent.get_number_of_decomposition_levels();
diff --git a/source/Tier2/read_codestream.m b/source/Tier2/read_codestream.m
index 5dac557..070b481 100644
--- a/source/Tier2/read_codestream.m
+++ b/source/Tier2/read_codestream.m
@@ -23,6 +23,7 @@ function read_codestream(currentTile, main_header, PPM_header)
 ty1 = currentTile.tile_pos_y + int32(currentTile.tile_size_y);
 
 codingStyle = get_coding_Styles(main_header, currentTile.header);
+c_NL = zeros(1, main_header.SIZ.Csiz);
 for c = 0:main_header.SIZ.Csiz - 1
     [codingStyle, codingStyleComponent] = get_coding_Styles(main_header, currentTile.header, c);
     c_NL(c + M_OFFSET) = codingStyleComponent.get_number_of_decomposition_levels();
diff --git a/source/Tier2/read_packet.m b/source/Tier2/read_packet.m
index 4308ced..919a687 100644
--- a/source/Tier2/read_packet.m
+++ b/source/Tier2/read_packet.m
@@ -48,6 +48,7 @@
 for b = 1:currentResolution.num_band
     currentPband = currentPrecinct.precinct_subbands(b);
     if currentPband.size_x * currentPband.size_y ~= 0
+        number_of_bytes = zeros(1, currentPband.numCblksX * currentPband.numCblksY);
         for idx = 0:currentPband.numCblksX * currentPband.numCblksY - 1
             number_of_bytes(count) = parse_packet_header(packetHeader, l, currentPband, currentPband.Cblks(idx + M_OFFSET), main_header.Cap15_b14_15);
             if DEBUG == 1
diff --git a/source/Tier2/simulate_packet.m b/source/Tier2/simulate_packet.m
index 219a691..ed71bd4 100644
--- a/source/Tier2/simulate_packet.m
+++ b/source/Tier2/simulate_packet.m
@@ -10,6 +10,7 @@
 total_bytes_of_packet_header = SOTlength + SODlength;
 
 codingStyle = get_coding_Styles(main_header, hTile.header);
+c_NL = zeros(1, main_header.SIZ.Csiz);
 for c = 0:main_header.SIZ.Csiz - 1
     [codingStyle, codingStyleComponent] = get_coding_Styles(main_header, hTile.header, c);
     c_NL(c + M_OFFSET) = codingStyleComponent.get_number_of_decomposition_levels();
diff --git a/source/box/convert_uint32_to_char.m b/source/box/convert_uint32_to_char.m
index c809922..c33e22c 100644
--- a/source/box/convert_uint32_to_char.m
+++ b/source/box/convert_uint32_to_char.m
@@ -2,6 +2,8 @@
 
 assert(isa(in, 'uint32'));
 
+tmp = zeros(1, 4, 'uint32');
+
 tmp(4) = bitand(in, 255);
 in = bitshift(in, -8);
 tmp(3) = bitand(in, 255);
diff --git a/source/box/jp2_color_conversion.m b/source/box/jp2_color_conversion.m
index bf4d56f..3b96621 100644
--- a/source/box/jp2_color_conversion.m
+++ b/source/box/jp2_color_conversion.m
@@ -5,6 +5,7 @@
 alpha = [];
 num_non_alpha = 0;
 if isempty(jp2Boxes.headerBox.cdef) == false
+    tmp = zeros([size(buf), main_header.SIZ.Csiz]);
     for c = 0:main_header.SIZ.Csiz - 1
         if jp2Boxes.headerBox.cdef.Typ_i(c + M_OFFSET) == 1
             alpha = buf(:, :, jp2Boxes.headerBox.cdef.Cn_i(c + M_OFFSET) + M_OFFSET) / max(max(buf(:, :, jp2Boxes.headerBox.cdef.Cn_i(c + M_OFFSET) + M_OFFSET)));
@@ -41,9 +42,10 @@
             case {'GREY', 'GRAY'}
                 fprintf('INFO: Embedde icc profile indicates Grayscale.\n');
                 cform = makecform('graytrc', iccProfile, 'Direction', 'inverse');
-                XYZ(:, :, 1) = zeros(size(composite_in));
+                XYZ = zeros([size(composite_in), 3]);
+                %XYZ(:, :, 1) = zeros(size(composite_in));
                 XYZ(:, :, 2) = composite_in;
-                XYZ(:, :, 3) = zeros(size(composite_in));
+                %XYZ(:, :, 3) = zeros(size(composite_in));
                 composite_out = applycform(XYZ / 2^(BPC + 1), cform);
                 composite_out = round(composite_out .* 2^(BPC + 1));
         end
@@ -68,6 +70,7 @@
             case 18 % sYCC
                 Lmin = 0;
                 Lmax = 255;
+                composite_tmp = zeros(size(composite_in));
                 composite_tmp(:, :, 1) = composite_in(:, :, 1) / Lmax;
                 composite_tmp(:, :, 2) = (composite_in(:, :, 2) - 128) / Lmax;
                 composite_tmp(:, :, 3) = (composite_in(:, :, 3) - 128) / Lmax;
diff --git a/source/coding_units/jp2_tile.m b/source/coding_units/jp2_tile.m
index c7ad991..4c3126b 100644
--- a/source/coding_units/jp2_tile.m
+++ b/source/coding_units/jp2_tile.m
@@ -55,6 +55,10 @@
         end
         function composite_out = put_tile_into_composite_output(inObj, main_header, composite_out, reduce_NL)
             M_OFFSET = 1;
+            c_tx0 = zeros(1, main_header.SIZ.Csiz);
+            c_tx1 = zeros(1, main_header.SIZ.Csiz);
+            c_ty0 = zeros(1, main_header.SIZ.Csiz);
+            c_ty1 = zeros(1, main_header.SIZ.Csiz);
             for c = 0:main_header.SIZ.Csiz - 1
                 [~, codingStyleComponent] = get_coding_Styles(main_header, inObj.header, c);
                 c_NL = codingStyleComponent.get_number_of_decomposition_levels();
diff --git a/source/utils/get_CSF_weight.m b/source/utils/get_CSF_weight.m
index 88f889c..5147d2c 100644
--- a/source/utils/get_CSF_weight.m
+++ b/source/utils/get_CSF_weight.m
@@ -1,5 +1,7 @@
 function val = get_CSF_weight(c, nb, b)
 
+CSF_table = zeros(6, 3, 3);
+
 % The following example value has been generated by Marcus Nadenau at EPFL.
 % for a viewing distance of 15 cm and a display resolution of 300 DPI.
 CSF_table(:, :, 3) = [; ...
diff --git a/source/utils/jp2_inputArguments.m b/source/utils/jp2_inputArguments.m
index fd3fa6a..37738ea 100644
--- a/source/utils/jp2_inputArguments.m
+++ b/source/utils/jp2_inputArguments.m
@@ -576,12 +576,17 @@
             end
             main_header = j2k_main_header;
             [numTiles_x, numTiles_y, use_SOP, use_PPM, use_TLM, use_PPT, use_PLT] = main_header.create(inObj);
-            for i = 0:length(tilepart_header) - 1
-                tilepart_header(i + M_OFFSET).create_COD(inObj);
-                tilepart_header(i + M_OFFSET).create_QCD(inObj);
-                tilepart_header(i + M_OFFSET).create_COC(inObj, i, inObj.numComponents, main_header);
-                tilepart_header(i + M_OFFSET).create_QCC(inObj, i, inObj.numComponents, main_header);
-                tilepart_header(i + M_OFFSET).create_POC(inObj, main_header);
+            if isempty(tilepart_header) == false
+                for i = 0:length(tilepart_header) - 1
+                    tilepart_header(i + M_OFFSET).create_COD(inObj);
+                    tilepart_header(i + M_OFFSET).create_QCD(inObj);
+                    tilepart_header(i + M_OFFSET).create_COC(inObj, i, inObj.numComponents, main_header);
+                    tilepart_header(i + M_OFFSET).create_QCC(inObj, i, inObj.numComponents, main_header);
+                    tilepart_header(i + M_OFFSET).create_POC(inObj, main_header);
+                end
+            else % just create a SOT if no optional parameters were given
+                tilepart_header = j2k_tile_part_header(0);
+                tilepart_header(1).idx = 0;
             end
         end
     end