diff --git a/utils/maskview.py b/utils/maskview.py
new file mode 100755
index 00000000..b4dd331d
--- /dev/null
+++ b/utils/maskview.py
@@ -0,0 +1,141 @@
+#!/usr/bin/env python3
+"""
+This tool allows to view segbits using a 2D frame vs. bit plot. It can read
+either mask.db files or segbits.db files. Multiple files can be read at once
+allowing to identify where a bit comes from.
+
+When a single file is read, a bit is marked as "O". When multiple files are
+read, a bit is denoted with a letter "A", "B" and so on depending on index
+of file that it belongs to.
+
+Duplicate bits (present in more than one files) are marked with "#"
+"""
+
+import sys
+import argparse
+import re
+
+# =============================================================================
+
+
+def load_just_bits(file_name):
+    """
+    Read bits from a .db or .rdb file. Ignores tags and bit values.
+    """
+
+    with open(file_name, "r") as fp:
+        lines = fp.readlines()
+
+    bits = set()
+    for line in lines:
+        for word in line.split(" "):
+            match = re.match("^(!?)([0-9]+)_([0-9]+)$", word)
+            if match is not None:
+                frm = int(match.group(2))
+                bit = int(match.group(3))
+            
+                bits.add((frm, bit,))
+
+    return bits
+
+# =============================================================================
+
+
+def main():
+
+    # Colors for TTY
+    if sys.stdout.isatty():
+
+        bit_colors = [
+            "\033[39m",
+            "\033[91m",
+            "\033[92m",
+            "\033[93m",
+            "\033[94m",
+            "\033[95m",
+            "\033[96m",
+            "\033[31m",
+            "\033[32m",
+            "\033[33m",
+            "\033[34m",
+            "\033[35m",
+            "\033[36m",
+        ]
+    
+        colors = {
+            "NONE": "\033[0m",
+            "DUPLICATE": "\033[101;97m",
+        }
+
+    # Colors for pipe
+    else:
+
+        bit_colors = [""]
+
+        colors = {
+            "NONE": "",
+            "DUPLICATE": "",
+        }
+
+    # .........................................................................
+
+    parser = argparse.ArgumentParser(
+        description=__doc__,
+        formatter_class=argparse.RawDescriptionHelpFormatter)
+    
+    parser.add_argument("files", nargs="*", type=str, help="Input files")
+
+    args = parser.parse_args()
+
+    # Load bits
+    all_bits = []
+    for i, f in enumerate(args.files):
+        bits = load_just_bits(f) 
+        all_bits.append(bits)
+
+        cstr = bit_colors[i % len(bit_colors)]
+        bstr = "O" if len(args.files) == 1 else chr(65+i)
+        print(cstr + bstr + colors["NONE"] + ": %s #%d" % (f, len(bits)))
+
+    print("")
+
+    max_frames = max([bit[0] for bits in all_bits for bit in bits]) + 1
+    max_bits   = max([bit[1] for bits in all_bits for bit in bits]) + 1
+
+    # Header
+    for r in range(3):
+        line = " " * 3
+        for c in range(max_bits):
+            bstr = "%03d" % c
+            line += bstr[r]
+        print(line)
+
+    print("")
+
+    # Display bits
+    for r in range(max_frames):
+        line = "%2d " % r
+        for c in range(max_bits):
+            got_bit = False
+            bit_str = colors["NONE"] + "-"
+            for i, bits in enumerate(all_bits):
+                cstr = bit_colors[i % len(bit_colors)]
+                bstr = "O" if len(args.files) == 1 else chr(65+i)
+                if (r, c) in bits:
+                    if not got_bit:
+                        bit_str = cstr + bstr
+                    else:
+                        bit_str = colors["DUPLICATE"] + "#" + colors["NONE"]
+                    got_bit = True
+ 
+            line += bit_str
+
+        line += colors["NONE"]
+        print(line)
+
+# =============================================================================
+
+
+if __name__ == "__main__":
+    main()
+
diff --git a/utils/segview.py b/utils/segview.py
new file mode 100755
index 00000000..347dcd4b
--- /dev/null
+++ b/utils/segview.py
@@ -0,0 +1,226 @@
+#!/usr/bin/env python3
+'''
+This script allows to load a number of .db or .rdb files and display bits in
+a nice visualization.
+
+When more than one files are loaded, a difference between them is shown.
+Differring bits are highlighted.
+'''
+import argparse
+import re
+import sys
+
+import itertools
+
+# =============================================================================
+
+
+def tagmap(tag):
+    """
+    Maps a specific tag name to its generic name
+    """
+
+    tag = tag.replace("CLBLL_L", "CLB")
+    tag = tag.replace("CLBLL_M", "CLB")
+    tag = tag.replace("CLBLM_L", "CLB")
+    tag = tag.replace("CLBLM_M", "CLB")
+
+    tag = tag.replace("SLICEL",  "SLICE")
+    tag = tag.replace("SLICEM",  "SLICE")
+
+    tag = tag.replace("LIOB33",  "IOB33")
+    tag = tag.replace("RIOB33",  "IOB33")
+
+    tag = tag.replace("LIOI3",  "IOI3")
+    tag = tag.replace("RIOI3",  "IOI3")
+
+    # TODO: Add other tag mappings
+
+    return tag
+
+
+def parse_bit(bit):
+    """
+    Decodes string describing a bit. Returns a tuple (frame, bit, value)
+    """
+    match = re.match("^(!?)([0-9]+)_([0-9]+)$", bit)
+    assert match != None, bit
+
+    val = int(match.group(1) != "!")
+    frm = int(match.group(2))
+    bit = int(match.group(3))
+
+    return frm, bit, val
+
+
+def load_and_sort_segbits(file_name, tagmap = lambda tag: tag):
+    """
+    Loads a segbit file (.db or .rdb). Skips bits containing '<' or '>'
+    """
+
+    # Load segbits
+    segbits = {}
+    with open(file_name, "r") as fp:
+        lines = fp.readlines()
+
+        # Parse lines
+        for line in lines:
+            line = line.strip()
+            fields = line.split()
+
+            if len(fields) < 2:
+                print("Malformed line: '%s'" % line)
+                continue
+
+            # Map name
+            feature = tagmap(fields[0])
+
+            # Decode bits
+            bits = []
+            for bit in fields[1:]:
+                if "<" in bit or ">" in bit:
+                    continue
+                bits.append(parse_bit(bit))
+
+            # Sort bits
+            bits.sort(key=lambda bit: (bit[0], bit[1],))
+            segbits[feature] = bits
+
+    return segbits
+
+# =============================================================================
+
+def make_header_lines(all_bits):
+    """
+    Formats header lines
+    """
+    lines = []
+
+    # Bit names
+    bit_names = ["%d_%d" % (b[0], b[1]) for b in all_bits]
+    bit_len = 6
+    for i in range(bit_len):
+        line = ""
+        for j in range(len(all_bits)):
+            bstr  = bit_names[j].ljust(bit_len).replace("_", "|")
+            line += bstr[i]
+        lines.append(line)
+
+    return lines
+
+
+def make_data_lines(all_tags, all_bits, segbits):
+    """
+    Formats data lines
+    """
+    lines = []
+
+    def map_f(b):
+        if b < 0: return "0"
+        if b > 0: return "1"
+        return "-"
+
+    # Bit data
+    for tag in all_tags:
+        if tag in segbits.keys():
+            lines.append("".join(map(map_f, segbits[tag])))
+        else:
+            lines.append(" " * len(all_bits))
+
+    return lines
+
+
+def main():
+
+    # Colors for TTY
+    if sys.stdout.isatty():
+        colors = {
+            "NONE": "\033[0m",
+            "DIFF": "\033[1m",
+        }
+
+    # Colors for pipe
+    else:
+        colors = {
+            "NONE": "",
+            "DIFF": "",
+        }
+
+    # ........................................................................
+
+    parser = argparse.ArgumentParser(
+        description=__doc__,
+        formatter_class=argparse.RawDescriptionHelpFormatter)
+
+    parser.add_argument("files", nargs="*", type=str, help="Input files")
+
+    args = parser.parse_args()
+
+    # Load segbits
+    all_segbits = []
+    for f in args.files:
+        all_segbits.append(load_and_sort_segbits(f, tagmap))
+
+    # List of all features and all bits
+    all_tags = set()
+    all_bits = set()
+    
+    for segbits in all_segbits:
+        all_tags |= set(segbits.keys())
+        for bits in segbits.values():
+            all_bits |= set([(b[0], b[1]) for b in bits])
+
+    all_tags = sorted(list(all_tags))
+    all_bits = sorted(list(all_bits))
+
+    # Convert bit lists to bit vectors    
+    for segbits in all_segbits:
+        for tag in segbits.keys():
+            vec = list([0]*len(all_bits))
+            for i, bit in enumerate(all_bits):
+                if (bit[0], bit[1], 0) in segbits[tag]:
+                    vec[i] = -1
+                if (bit[0], bit[1], 1) in segbits[tag]:
+                    vec[i] = +1
+            segbits[tag] = vec
+
+
+    # Make header and data lines
+    header_lines = make_header_lines(all_bits)
+    data_lines = [make_data_lines(all_tags, all_bits, segbits) for segbits in all_segbits]
+
+    # Display
+    max_tag_len = max([len(tag) for tag in all_tags])
+
+    for l in header_lines:
+        line = " " * max_tag_len + " "
+        for i in range(len(all_segbits)):
+            line += l + " "
+        print(line)
+
+    data_len = len(all_bits)
+    for i, tag in enumerate(all_tags):
+        line = tag.ljust(max_tag_len) + " "
+
+        diff = bytearray(data_len)
+        for l1, l2 in itertools.combinations(data_lines, 2):
+            for j in range(data_len):
+                if l1[i][j] != l2[i][j]:
+                    diff[j] = 1
+
+        for l in data_lines:
+            for j in range(data_len):
+                if diff[j]:
+                    line += colors["DIFF"] + l[i][j] + colors["NONE"]
+                else:
+                    line += l[i][j]
+            line += " "
+
+        print(line)
+
+# =============================================================================
+
+
+if __name__ == "__main__":
+    main()
+