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  • Steganography Experiment - Trouble hiding message bits in DCT coefficients

    - by JohnHankinson
    I have an application requiring me to be able to embed loss-less data into an image. As such I've been experimenting with steganography, specifically via modification of DCT coefficients as the method I select, apart from being loss-less must also be relatively resilient against format conversion, scaling/DSP etc. From the research I've done thus far this method seems to be the best candidate. I've seen a number of papers on the subject which all seem to neglect specific details (some neglect to mention modification of 0 coefficients, or modification of AC coefficient etc). After combining the findings and making a few modifications of my own which include: 1) Using a more quantized version of the DCT matrix to ensure we only modify coefficients that would still be present should the image be JPEG'ed further or processed (I'm using this in place of simply following a zig-zag pattern). 2) I'm modifying bit 4 instead of the LSB and then based on what the original bit value was adjusting the lower bits to minimize the difference. 3) I'm only modifying the blue channel as it should be the least visible. This process must modify the actual image and not the DCT values stored in file (like jsteg) as there is no guarantee the file will be a JPEG, it may also be opened and re-saved at a later stage in a different format. For added robustness I've included the message multiple times and use the bits that occur most often, I had considered using a QR code as the message data or simply applying the reed-solomon error correction, but for this simple application and given that the "message" in question is usually going to be between 10-32 bytes I have plenty of room to repeat it which should provide sufficient redundancy to recover the true bits. No matter what I do I don't seem to be able to recover the bits at the decode stage. I've tried including / excluding various checks (even if it degrades image quality for the time being). I've tried using fixed point vs. double arithmetic, moving the bit to encode, I suspect that the message bits are being lost during the IDCT back to image. Any thoughts or suggestions on how to get this working would be hugely appreciated. (PS I am aware that the actual DCT/IDCT could be optimized from it's naive On4 operation using row column algorithm, or an FDCT like AAN, but for now it just needs to work :) ) Reference Papers: http://www.lokminglui.com/dct.pdf http://arxiv.org/ftp/arxiv/papers/1006/1006.1186.pdf Code for the Encode/Decode process in C# below: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Drawing.Imaging; using System.Drawing; namespace ImageKey { public class Encoder { public const int HIDE_BIT_POS = 3; // use bit position 4 (1 << 3). public const int HIDE_COUNT = 16; // Number of times to repeat the message to avoid error. // JPEG Standard Quantization Matrix. // (to get higher quality multiply by (100-quality)/50 .. // for lower than 50 multiply by 50/quality. Then round to integers and clip to ensure only positive integers. public static double[] Q = {16,11,10,16,24,40,51,61, 12,12,14,19,26,58,60,55, 14,13,16,24,40,57,69,56, 14,17,22,29,51,87,80,62, 18,22,37,56,68,109,103,77, 24,35,55,64,81,104,113,92, 49,64,78,87,103,121,120,101, 72,92,95,98,112,100,103,99}; // Maximum qauality quantization matrix (if all 1's doesn't modify coefficients at all). public static double[] Q2 = {1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1}; public static Bitmap Encode(Bitmap b, string key) { Bitmap response = new Bitmap(b.Width, b.Height, PixelFormat.Format32bppArgb); uint imgWidth = ((uint)b.Width) & ~((uint)7); // Maximum usable X resolution (divisible by 8). uint imgHeight = ((uint)b.Height) & ~((uint)7); // Maximum usable Y resolution (divisible by 8). // Start be transferring the unmodified image portions. // As we'll be using slightly less width/height for the encoding process we'll need the edges to be populated. for (int y = 0; y < b.Height; y++) for (int x = 0; x < b.Width; x++) { if( (x >= imgWidth && x < b.Width) || (y>=imgHeight && y < b.Height)) response.SetPixel(x, y, b.GetPixel(x, y)); } // Setup the counters and byte data for the message to encode. StringBuilder sb = new StringBuilder(); for(int i=0;i<HIDE_COUNT;i++) sb.Append(key); byte[] codeBytes = System.Text.Encoding.ASCII.GetBytes(sb.ToString()); int bitofs = 0; // Current bit position we've encoded too. int totalBits = (codeBytes.Length * 8); // Total number of bits to encode. for (int y = 0; y < imgHeight; y += 8) { for (int x = 0; x < imgWidth; x += 8) { int[] redData = GetRedChannelData(b, x, y); int[] greenData = GetGreenChannelData(b, x, y); int[] blueData = GetBlueChannelData(b, x, y); int[] newRedData; int[] newGreenData; int[] newBlueData; if (bitofs < totalBits) { double[] redDCT = DCT(ref redData); double[] greenDCT = DCT(ref greenData); double[] blueDCT = DCT(ref blueData); int[] redDCTI = Quantize(ref redDCT, ref Q2); int[] greenDCTI = Quantize(ref greenDCT, ref Q2); int[] blueDCTI = Quantize(ref blueDCT, ref Q2); int[] blueDCTC = Quantize(ref blueDCT, ref Q); HideBits(ref blueDCTI, ref blueDCTC, ref bitofs, ref totalBits, ref codeBytes); double[] redDCT2 = DeQuantize(ref redDCTI, ref Q2); double[] greenDCT2 = DeQuantize(ref greenDCTI, ref Q2); double[] blueDCT2 = DeQuantize(ref blueDCTI, ref Q2); newRedData = IDCT(ref redDCT2); newGreenData = IDCT(ref greenDCT2); newBlueData = IDCT(ref blueDCT2); } else { newRedData = redData; newGreenData = greenData; newBlueData = blueData; } MapToRGBRange(ref newRedData); MapToRGBRange(ref newGreenData); MapToRGBRange(ref newBlueData); for(int dy=0;dy<8;dy++) { for(int dx=0;dx<8;dx++) { int col = (0xff<<24) + (newRedData[dx+(dy*8)]<<16) + (newGreenData[dx+(dy*8)]<<8) + (newBlueData[dx+(dy*8)]); response.SetPixel(x+dx,y+dy,Color.FromArgb(col)); } } } } if (bitofs < totalBits) throw new Exception("Failed to encode data - insufficient cover image coefficients"); return (response); } public static void HideBits(ref int[] DCTMatrix, ref int[] CMatrix, ref int bitofs, ref int totalBits, ref byte[] codeBytes) { int tempValue = 0; for (int u = 0; u < 8; u++) { for (int v = 0; v < 8; v++) { if ( (u != 0 || v != 0) && CMatrix[v+(u*8)] != 0 && DCTMatrix[v+(u*8)] != 0) { if (bitofs < totalBits) { tempValue = DCTMatrix[v + (u * 8)]; int bytePos = (bitofs) >> 3; int bitPos = (bitofs) % 8; byte mask = (byte)(1 << bitPos); byte value = (byte)((codeBytes[bytePos] & mask) >> bitPos); // 0 or 1. if (value == 0) { int a = DCTMatrix[v + (u * 8)] & (1 << HIDE_BIT_POS); if (a != 0) DCTMatrix[v + (u * 8)] |= (1 << HIDE_BIT_POS) - 1; DCTMatrix[v + (u * 8)] &= ~(1 << HIDE_BIT_POS); } else if (value == 1) { int a = DCTMatrix[v + (u * 8)] & (1 << HIDE_BIT_POS); if (a == 0) DCTMatrix[v + (u * 8)] &= ~((1 << HIDE_BIT_POS) - 1); DCTMatrix[v + (u * 8)] |= (1 << HIDE_BIT_POS); } if (DCTMatrix[v + (u * 8)] != 0) bitofs++; else DCTMatrix[v + (u * 8)] = tempValue; } } } } } public static void MapToRGBRange(ref int[] data) { for(int i=0;i<data.Length;i++) { data[i] += 128; if(data[i] < 0) data[i] = 0; else if(data[i] > 255) data[i] = 255; } } public static int[] GetRedChannelData(Bitmap b, int sx, int sy) { int[] data = new int[8 * 8]; for (int y = sy; y < (sy + 8); y++) { for (int x = sx; x < (sx + 8); x++) { uint col = (uint)b.GetPixel(x,y).ToArgb(); data[(x - sx) + ((y - sy) * 8)] = (int)((col >> 16) & 0xff) - 128; } } return (data); } public static int[] GetGreenChannelData(Bitmap b, int sx, int sy) { int[] data = new int[8 * 8]; for (int y = sy; y < (sy + 8); y++) { for (int x = sx; x < (sx + 8); x++) { uint col = (uint)b.GetPixel(x, y).ToArgb(); data[(x - sx) + ((y - sy) * 8)] = (int)((col >> 8) & 0xff) - 128; } } return (data); } public static int[] GetBlueChannelData(Bitmap b, int sx, int sy) { int[] data = new int[8 * 8]; for (int y = sy; y < (sy + 8); y++) { for (int x = sx; x < (sx + 8); x++) { uint col = (uint)b.GetPixel(x, y).ToArgb(); data[(x - sx) + ((y - sy) * 8)] = (int)((col >> 0) & 0xff) - 128; } } return (data); } public static int[] Quantize(ref double[] DCTMatrix, ref double[] Q) { int[] DCTMatrixOut = new int[8*8]; for (int u = 0; u < 8; u++) { for (int v = 0; v < 8; v++) { DCTMatrixOut[v + (u * 8)] = (int)Math.Round(DCTMatrix[v + (u * 8)] / Q[v + (u * 8)]); } } return(DCTMatrixOut); } public static double[] DeQuantize(ref int[] DCTMatrix, ref double[] Q) { double[] DCTMatrixOut = new double[8*8]; for (int u = 0; u < 8; u++) { for (int v = 0; v < 8; v++) { DCTMatrixOut[v + (u * 8)] = (double)DCTMatrix[v + (u * 8)] * Q[v + (u * 8)]; } } return(DCTMatrixOut); } public static double[] DCT(ref int[] data) { double[] DCTMatrix = new double[8 * 8]; for (int v = 0; v < 8; v++) { for (int u = 0; u < 8; u++) { double cu = 1; if (u == 0) cu = (1.0 / Math.Sqrt(2.0)); double cv = 1; if (v == 0) cv = (1.0 / Math.Sqrt(2.0)); double sum = 0.0; for (int y = 0; y < 8; y++) { for (int x = 0; x < 8; x++) { double s = data[x + (y * 8)]; double dctVal = Math.Cos((2 * y + 1) * v * Math.PI / 16) * Math.Cos((2 * x + 1) * u * Math.PI / 16); sum += s * dctVal; } } DCTMatrix[u + (v * 8)] = (0.25 * cu * cv * sum); } } return (DCTMatrix); } public static int[] IDCT(ref double[] DCTMatrix) { int[] Matrix = new int[8 * 8]; for (int y = 0; y < 8; y++) { for (int x = 0; x < 8; x++) { double sum = 0; for (int v = 0; v < 8; v++) { for (int u = 0; u < 8; u++) { double cu = 1; if (u == 0) cu = (1.0 / Math.Sqrt(2.0)); double cv = 1; if (v == 0) cv = (1.0 / Math.Sqrt(2.0)); double idctVal = (cu * cv) / 4.0 * Math.Cos((2 * y + 1) * v * Math.PI / 16) * Math.Cos((2 * x + 1) * u * Math.PI / 16); sum += (DCTMatrix[u + (v * 8)] * idctVal); } } Matrix[x + (y * 8)] = (int)Math.Round(sum); } } return (Matrix); } } public class Decoder { public static string Decode(Bitmap b, int expectedLength) { expectedLength *= Encoder.HIDE_COUNT; uint imgWidth = ((uint)b.Width) & ~((uint)7); // Maximum usable X resolution (divisible by 8). uint imgHeight = ((uint)b.Height) & ~((uint)7); // Maximum usable Y resolution (divisible by 8). // Setup the counters and byte data for the message to decode. byte[] codeBytes = new byte[expectedLength]; byte[] outBytes = new byte[expectedLength / Encoder.HIDE_COUNT]; int bitofs = 0; // Current bit position we've decoded too. int totalBits = (codeBytes.Length * 8); // Total number of bits to decode. for (int y = 0; y < imgHeight; y += 8) { for (int x = 0; x < imgWidth; x += 8) { int[] blueData = ImageKey.Encoder.GetBlueChannelData(b, x, y); double[] blueDCT = ImageKey.Encoder.DCT(ref blueData); int[] blueDCTI = ImageKey.Encoder.Quantize(ref blueDCT, ref Encoder.Q2); int[] blueDCTC = ImageKey.Encoder.Quantize(ref blueDCT, ref Encoder.Q); if (bitofs < totalBits) GetBits(ref blueDCTI, ref blueDCTC, ref bitofs, ref totalBits, ref codeBytes); } } bitofs = 0; for (int i = 0; i < (expectedLength / Encoder.HIDE_COUNT) * 8; i++) { int bytePos = (bitofs) >> 3; int bitPos = (bitofs) % 8; byte mask = (byte)(1 << bitPos); List<int> values = new List<int>(); int zeroCount = 0; int oneCount = 0; for (int j = 0; j < Encoder.HIDE_COUNT; j++) { int val = (codeBytes[bytePos + ((expectedLength / Encoder.HIDE_COUNT) * j)] & mask) >> bitPos; values.Add(val); if (val == 0) zeroCount++; else oneCount++; } if (oneCount >= zeroCount) outBytes[bytePos] |= mask; bitofs++; values.Clear(); } return (System.Text.Encoding.ASCII.GetString(outBytes)); } public static void GetBits(ref int[] DCTMatrix, ref int[] CMatrix, ref int bitofs, ref int totalBits, ref byte[] codeBytes) { for (int u = 0; u < 8; u++) { for (int v = 0; v < 8; v++) { if ((u != 0 || v != 0) && CMatrix[v + (u * 8)] != 0 && DCTMatrix[v + (u * 8)] != 0) { if (bitofs < totalBits) { int bytePos = (bitofs) >> 3; int bitPos = (bitofs) % 8; byte mask = (byte)(1 << bitPos); int value = DCTMatrix[v + (u * 8)] & (1 << Encoder.HIDE_BIT_POS); if (value != 0) codeBytes[bytePos] |= mask; bitofs++; } } } } } } } UPDATE: By switching to using a QR Code as the source message and swapping a pair of coefficients in each block instead of bit manipulation I've been able to get the message to survive the transform. However to get the message to come through without corruption I have to adjust both coefficients as well as swap them. For example swapping (3,4) and (4,3) in the DCT matrix and then respectively adding 8 and subtracting 8 as an arbitrary constant seems to work. This survives a re-JPEG'ing of 96 but any form of scaling/cropping destroys the message again. I was hoping that by operating on mid to low frequency values that the message would be preserved even under some light image manipulation.

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  • Is there any sence in performing binary AND with a number where all bits are set to 1

    - by n535
    Greetings everybody. I have seen examples of such operations for so many times that i began to think that i am getting something wrong with binary arithmetics. Is there any sense to perform the following: byte value = someAnotherByteValue & 0xFF; I don't really understand this, because it does not change anything anyway. Thanks for help. P.S. I was trying to search for information both elsewhere and here, but unsuccessfully.

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  • Convert arbitrary size of byte[] to BigInteger[] and then safely convert back to exactly the same by

    - by PatlaDJ
    I believe conversion exactly to BigInteger[] would be optimal in my case. Anyone had done or found this written in Java and willing to share? So imagine I have arbitrary size byte[] = {0xff,0x3e,0x12,0x45,0x1d,0x11,0x2a,0x80,0x81,0x45,0x1d,0x11,0x2a,0x80,0x81} How do I convert it to array of BigInteger's and then be able to recover it back the original byte array safely? ty in advance.

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  • Types questions in ANSI C

    - by shaharg
    Hi, I having few questions about typed in ANSI C: 1. what's the difference between "\x" in the beginning of a char to 0x in the beginning of char (or in any other case for this matter). AFAIK, they both means that this is hexadecimal.. so what's the difference. when casting char to (unsigned), not (unsigned char) - what does it mean? why (unsigned)'\xFF' != 0xFF? Thanks!

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  • Bit convector : Get byte array from string

    - by nCdy
    When I have a string like "0xd8 0xff 0xe0" I do Text.Split(' ').Select(part => byte.Parse(part, System.Globalization.NumberStyles.HexNumber)).ToArray(); But if I got string like "0xd8ffe0" I don't know what to do ? also I'm able for recommendations how to write byte array as one string.

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  • Is the Google Annotations Gallery useful in production code?

    - by cafe
    I could actually see a use for the Google Annotations Gallery in real code: Stumble across code that somehow works beyond all reason? Life's short. Mark it with @Magic and move on: @Magic public static int negate(int n) { return new Byte((byte) 0xFF).hashCode() / (int) (short) '\uFFFF' * ~0 * Character.digit ('0', 0) * n * (Integer.MAX_VALUE * 2 + 1) / (Byte.MIN_VALUE >> 7) * (~1 | 1); } This is a serious question. Could this be used in an actual code review?

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  • bluetooth not working on Ubuntu 13.10

    - by iacopo
    I upgrated ubuntu from 13.4 to 13.10 and my bluetooth stopped working. When I open bluetooth I'm able to put it ON but the visibility doesn't show anything and didn't detect any device. when I: dmesg | grep Blue [ 2.046249] usb 3-1: Product: Bluetooth V2.0 Dongle [ 2.046252] usb 3-1: Manufacturer: Bluetooth v2.0 [ 15.255710] Bluetooth: Core ver 2.16 [ 15.255748] Bluetooth: HCI device and connection manager initialized [ 15.255759] Bluetooth: HCI socket layer initialized [ 15.255765] Bluetooth: L2CAP socket layer initialized [ 15.255776] Bluetooth: SCO socket layer initialized [ 20.110379] Bluetooth: BNEP (Ethernet Emulation) ver 1.3 [ 20.110386] Bluetooth: BNEP filters: protocol multicast [ 20.110400] Bluetooth: BNEP socket layer initialized [ 20.120635] Bluetooth: RFCOMM TTY layer initialized [ 20.120656] Bluetooth: RFCOMM socket layer initialized [ 20.120660] Bluetooth: RFCOMM ver 1.11 when I digit: lsusb Bus 007 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 002 Device 002: ID 0bc2:2300 Seagate RSS LLC Expansion Portable Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 006 Device 002: ID 0e6a:6001 Megawin Technology Co., Ltd GEMBIRD Flexible keyboard KB-109F-B-DE Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 005 Device 002: ID 13ee:0001 MosArt Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 003 Device 002: ID 0a12:0001 Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode) Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub when I: hciconfig -a hci0: Type: BR/EDR Bus: USB BD Address: 00:1B:10:00:2A:EC ACL MTU: 1017:8 SCO MTU: 64:0 DOWN RX bytes:457 acl:0 sco:0 events:16 errors:0 TX bytes:68 acl:0 sco:0 commands:16 errors:0 Features: 0xff 0xff 0x8d 0xfe 0x9b 0xf9 0x00 0x80 Packet type: DM1 DM3 DM5 DH1 DH3 DH5 HV1 HV2 HV3 Link policy: Link mode: SLAVE ACCEPT when I digit: rfkill list 0: phy0: Wireless LAN Soft blocked: yes Hard blocked: no 1: hci0: Bluetooth Soft blocked: no Hard blocked: no when I digit: sudo gedit /etc/bluetooth/main.conf [General] # List of plugins that should not be loaded on bluetoothd startup #DisablePlugins = network,input # Default adaper name # %h - substituted for hostname # %d - substituted for adapter id Name = %h-%d # Default device class. Only the major and minor device class bits are # considered. Class = 0x000100 # How long to stay in discoverable mode before going back to non-discoverable # The value is in seconds. Default is 180, i.e. 3 minutes. # 0 = disable timer, i.e. stay discoverable forever DiscoverableTimeout = 0 # How long to stay in pairable mode before going back to non-discoverable # The value is in seconds. Default is 0. # 0 = disable timer, i.e. stay pairable forever PairableTimeout = 0 # Use some other page timeout than the controller default one # which is 16384 (10 seconds). PageTimeout = 8192 # Automatic connection for bonded devices driven by platform/user events. # If a platform plugin uses this mechanism, automatic connections will be # enabled during the interval defined below. Initially, this feature # intends to be used to establish connections to ATT channels. AutoConnectTimeout = 60 # What value should be assumed for the adapter Powered property when # SetProperty(Powered, ...) hasn't been called yet. Defaults to true InitiallyPowered = true # Remember the previously stored Powered state when initializing adapters RememberPowered = false # Use vendor id source (assigner), vendor, product and version information for # DID profile support. The values are separated by ":" and assigner, VID, PID # and version. # Possible vendor id source values: bluetooth, usb (defaults to usb) #DeviceID = bluetooth:1234:5678:abcd # Do reverse service discovery for previously unknown devices that connect to # us. This option is really only needed for qualification since the BITE tester # doesn't like us doing reverse SDP for some test cases (though there could in # theory be other useful purposes for this too). Defaults to true. ReverseServiceDiscovery = true # Enable name resolving after inquiry. Set it to 'false' if you don't need # remote devices name and want shorter discovery cycle. Defaults to 'true'. NameResolving = true # Enable runtime persistency of debug link keys. Default is false which # makes debug link keys valid only for the duration of the connection # that they were created for. DebugKeys = false # Enable the GATT functionality. Default is false EnableGatt = false when I digit: dmesg | grep Bluetooth [ 2.013041] usb 3-1: Product: Bluetooth V2.0 Dongle [ 2.013049] usb 3-1: Manufacturer: Bluetooth v2.0 [ 13.798293] Bluetooth: Core ver 2.16 [ 13.798338] Bluetooth: HCI device and connection manager initialized [ 13.798352] Bluetooth: HCI socket layer initialized [ 13.798357] Bluetooth: L2CAP socket layer initialized [ 13.798368] Bluetooth: SCO socket layer initialized [ 20.184162] Bluetooth: BNEP (Ethernet Emulation) ver 1.3 [ 20.184173] Bluetooth: BNEP filters: protocol multicast [ 20.184197] Bluetooth: BNEP socket layer initialized [ 20.238947] Bluetooth: RFCOMM TTY layer initialized [ 20.238983] Bluetooth: RFCOMM socket layer initialized [ 20.239018] Bluetooth: RFCOMM ver 1.11 When I digit: uname -a Linux casa-desktop 3.11.0-13-generic #20-Ubuntu SMP Wed Oct 23 07:38:26 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux When I digit: lsmod Module Size Used by parport_pc 32701 0 rfcomm 69070 4 bnep 19564 2 ppdev 17671 0 ip6t_REJECT 12910 1 xt_hl 12521 6 ip6t_rt 13507 3 nf_conntrack_ipv6 18938 9 nf_defrag_ipv6 34616 1 nf_conntrack_ipv6 ipt_REJECT 12541 1 xt_LOG 17718 8 xt_limit 12711 11 xt_tcpudp 12884 32 xt_addrtype 12635 4 nf_conntrack_ipv4 15012 9 nf_defrag_ipv4 12729 1 nf_conntrack_ipv4 xt_conntrack 12760 18 ip6table_filter 12815 1 ip6_tables 27025 1 ip6table_filter nf_conntrack_netbios_ns 12665 0 nf_conntrack_broadcast 12589 1 nf_conntrack_netbios_ns nf_nat_ftp 12741 0 nf_nat 26653 1 nf_nat_ftp kvm_amd 59958 0 nf_conntrack_ftp 18608 1 nf_nat_ftp kvm 431315 1 kvm_amd nf_conntrack 91736 8 nf_nat_ftp,nf_conntrack_netbios_ns,nf_nat,xt_conntrack,nf_conntrack_broadcast,nf_conntrack_ftp,nf_conntrack_ipv4,nf_conntrack_ipv6 iptable_filter 12810 1 crct10dif_pclmul 14289 0 crc32_pclmul 13113 0 ip_tables 27239 1 iptable_filter snd_hda_codec_realtek 55704 1 ghash_clmulni_intel 13259 0 aesni_intel 55624 0 aes_x86_64 17131 1 aesni_intel snd_hda_codec_hdmi 41117 1 x_tables 34059 13 ip6table_filter,xt_hl,ip_tables,xt_tcpudp,xt_limit,xt_conntrack,xt_LOG,iptable_filter,ip6t_rt,ipt_REJECT,ip6_tables,xt_addrtype,ip6t_REJECT lrw 13257 1 aesni_intel snd_hda_intel 48171 5 gf128mul 14951 1 lrw glue_helper 13990 1 aesni_intel ablk_helper 13597 1 aesni_intel joydev 17377 0 cryptd 20329 3 ghash_clmulni_intel,aesni_intel,ablk_helper snd_hda_codec 188738 3 snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_intel arc4 12608 2 snd_hwdep 13602 1 snd_hda_codec rt2800pci 18690 0 snd_pcm 102033 3 snd_hda_codec_hdmi,snd_hda_codec,snd_hda_intel radeon 1402449 3 rt2800lib 79963 1 rt2800pci btusb 28267 0 rt2x00pci 13287 1 rt2800pci rt2x00mmio 13603 1 rt2800pci snd_page_alloc 18710 2 snd_pcm,snd_hda_intel rt2x00lib 55238 4 rt2x00pci,rt2800lib,rt2800pci,rt2x00mmio snd_seq_midi 13324 0 mac80211 596969 3 rt2x00lib,rt2x00pci,rt2800lib snd_seq_midi_event 14899 1 snd_seq_midi ttm 83995 1 radeon snd_rawmidi 30095 1 snd_seq_midi cfg80211 479757 2 mac80211,rt2x00lib drm_kms_helper 52651 1 radeon snd_seq 61560 2 snd_seq_midi_event,snd_seq_midi bluetooth 371880 12 bnep,btusb,rfcomm microcode 23518 0 eeprom_93cx6 13344 1 rt2800pci snd_seq_device 14497 3 snd_seq,snd_rawmidi,snd_seq_midi crc_ccitt 12707 1 rt2800lib snd_timer 29433 2 snd_pcm,snd_seq snd 69141 21 snd_hda_codec_realtek,snd_hwdep,snd_timer,snd_hda_codec_hdmi,snd_pcm,snd_seq,snd_rawmidi,snd_hda_codec,snd_hda_intel,snd_seq_device,snd_seq_midi psmouse 97626 0 drm 296739 5 ttm,drm_kms_helper,radeon k10temp 13126 0 soundcore 12680 1 snd serio_raw 13413 0 i2c_algo_bit 13413 1 radeon i2c_piix4 22106 0 video 19318 0 mac_hid 13205 0 lp 17759 0 parport 42299 3 lp,ppdev,parport_pc hid_generic 12548 0 usbhid 53014 0 hid 105818 2 hid_generic,usbhid pata_acpi 13038 0 usb_storage 62062 1 r8169 67341 0 sdhci_pci 18985 0 sdhci 42630 1 sdhci_pci mii 13934 1 r8169 pata_atiixp 13242 0 ohci_pci 13561 0 ahci 25819 2 libahci 31898 1 ahci Someone can help me?

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  • Anatomy of a .NET Assembly - Custom attribute encoding

    - by Simon Cooper
    In my previous post, I covered how field, method, and other types of signatures are encoded in a .NET assembly. Custom attribute signatures differ quite a bit from these, which consequently affects attribute specifications in C#. Custom attribute specifications In C#, you can apply a custom attribute to a type or type member, specifying a constructor as well as the values of fields or properties on the attribute type: public class ExampleAttribute : Attribute { public ExampleAttribute(int ctorArg1, string ctorArg2) { ... } public Type ExampleType { get; set; } } [Example(5, "6", ExampleType = typeof(string))] public class C { ... } How does this specification actually get encoded and stored in an assembly? Specification blob values Custom attribute specification signatures use the same building blocks as other types of signatures; the ELEMENT_TYPE structure. However, they significantly differ from other types of signatures, in that the actual parameter values need to be stored along with type information. There are two types of specification arguments in a signature blob; fixed args and named args. Fixed args are the arguments to the attribute type constructor, named arguments are specified after the constructor arguments to provide a value to a field or property on the constructed attribute type (PropertyName = propValue) Values in an attribute blob are limited to one of the basic types (one of the number types, character, or boolean), a reference to a type, an enum (which, in .NET, has to use one of the integer types as a base representation), or arrays of any of those. Enums and the basic types are easy to store in a blob - you simply store the binary representation. Strings are stored starting with a compressed integer indicating the length of the string, followed by the UTF8 characters. Array values start with an integer indicating the number of elements in the array, then the item values concatentated together. Rather than using a coded token, Type values are stored using a string representing the type name and fully qualified assembly name (for example, MyNs.MyType, MyAssembly, Version=1.0.0.0, Culture=neutral, PublicKeyToken=0123456789abcdef). If the type is in the current assembly or mscorlib then just the type name can be used. This is probably done to prevent direct references between assemblies solely because of attribute specification arguments; assemblies can be loaded in the reflection-only context and attribute arguments still processed, without loading the entire assembly. Fixed and named arguments Each entry in the CustomAttribute metadata table contains a reference to the object the attribute is applied to, the attribute constructor, and the specification blob. The number and type of arguments to the constructor (the fixed args) can be worked out by the method signature referenced by the attribute constructor, and so the fixed args can simply be concatenated together in the blob without any extra type information. Named args are different. These specify the value to assign to a field or property once the attribute type has been constructed. In the CLR, fields and properties can be overloaded just on their type; different fields and properties can have the same name. Therefore, to uniquely identify a field or property you need: Whether it's a field or property (indicated using byte values 0x53 and 0x54, respectively) The field or property type The field or property name After the fixed arg values is a 2-byte number specifying the number of named args in the blob. Each named argument has the above information concatenated together, mostly using the basic ELEMENT_TYPE values, in the same way as a method or field signature. A Type argument is represented using the byte 0x50, and an enum argument is represented using the byte 0x55 followed by a string specifying the name and assembly of the enum type. The named argument property information is followed by the argument value, using the same encoding as fixed args. Boxed objects This would be all very well, were it not for object and object[]. Arguments and properties of type object allow a value of any allowed argument type to be specified. As a result, more information needs to be specified in the blob to interpret the argument bytes as the correct type. So, the argument value is simple prepended with the type of the value by specifying the ELEMENT_TYPE or name of the enum the value represents. For named arguments, a field or property of type object is represented using the byte 0x51, with the actual type specified in the argument value. Some examples... All property signatures start with the 2-byte value 0x0001. Similar to my previous post in the series, names in capitals correspond to a particular byte value in the ELEMENT_TYPE structure. For strings, I'll simply give the string value, rather than the length and UTF8 encoding in the actual blob. I'll be using the following enum and attribute types to demonstrate specification encodings: class AttrAttribute : Attribute { public AttrAttribute() {} public AttrAttribute(Type[] tArray) {} public AttrAttribute(object o) {} public AttrAttribute(MyEnum e) {} public AttrAttribute(ushort x, int y) {} public AttrAttribute(string str, Type type1, Type type2) {} public int Prop1 { get; set; } public object Prop2 { get; set; } public object[] ObjectArray; } enum MyEnum : int { Val1 = 1, Val2 = 2 } Now, some examples: Here, the the specification binds to the (ushort, int) attribute constructor, with fixed args only. The specification blob starts off with a prolog, followed by the two constructor arguments, then the number of named arguments (zero): [Attr(42, 84)] 0x0001 0x002a 0x00000054 0x0000 An example of string and type encoding: [Attr("MyString", typeof(Array), typeof(System.Windows.Forms.Form))] 0x0001 "MyString" "System.Array" "System.Windows.Forms.Form, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" 0x0000 As you can see, the full assembly specification of a type is only needed if the type isn't in the current assembly or mscorlib. Note, however, that the C# compiler currently chooses to fully-qualify mscorlib types anyway. An object argument (this binds to the object attribute constructor), and two named arguments (a null string is represented by 0xff and the empty string by 0x00) [Attr((ushort)40, Prop1 = 12, Prop2 = "")] 0x0001 U2 0x0028 0x0002 0x54 I4 "Prop1" 0x0000000c 0x54 0x51 "Prop2" STRING 0x00 Right, more complicated now. A type array as a fixed argument: [Attr(new[] { typeof(string), typeof(object) })] 0x0001 0x00000002 // the number of elements "System.String" "System.Object" 0x0000 An enum value, which is simply represented using the underlying value. The CLR works out that it's an enum using information in the attribute constructor signature: [Attr(MyEnum.Val1)] 0x0001 0x00000001 0x0000 And finally, a null array, and an object array as a named argument: [Attr((Type[])null, ObjectArray = new object[] { (byte)2, typeof(decimal), null, MyEnum.Val2 })] 0x0001 0xffffffff 0x0001 0x53 SZARRAY 0x51 "ObjectArray" 0x00000004 U1 0x02 0x50 "System.Decimal" STRING 0xff 0x55 "MyEnum" 0x00000002 As you'll notice, a null object is encoded as a null string value, and a null array is represented using a length of -1 (0xffffffff). How does this affect C#? So, we can now explain why the limits on attribute arguments are so strict in C#. Attribute specification blobs are limited to basic numbers, enums, types, and arrays. As you can see, this is because the raw CLR encoding can only accommodate those types. Special byte patterns have to be used to indicate object, string, Type, or enum values in named arguments; you can't specify an arbitary object type, as there isn't a generalised way of encoding the resulting value in the specification blob. In particular, decimal values can't be encoded, as it isn't a 'built-in' CLR type that has a native representation (you'll notice that decimal constants in C# programs are compiled as several integer arguments to DecimalConstantAttribute). Jagged arrays also aren't natively supported, although you can get around it by using an array as a value to an object argument: [Attr(new object[] { new object[] { new Type[] { typeof(string) } }, 42 })] Finally... Phew! That was a bit longer than I thought it would be. Custom attribute encodings are complicated! Hopefully this series has been an informative look at what exactly goes on inside a .NET assembly. In the next blog posts, I'll be carrying on with the 'Inside Red Gate' series.

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  • Web Sockets: Browser won't receive the message, complains about it not starting with 0x00 (byte)

    - by giggsey
    Here is my code: import java.net.*; import java.io.*; import java.util.*; import org.jibble.pircbot.*; public class WebSocket { public static int port = 12345; public static ArrayList<WebSocketClient> clients = new ArrayList<WebSocketClient>(); public static ArrayList<Boolean> handshakes = new ArrayList<Boolean>(); public static ArrayList<String> nicknames = new ArrayList<String>(); public static ArrayList<String> channels = new ArrayList<String>(); public static int indexNum; public static void main(String args[]) { try { ServerSocket ss = new ServerSocket(WebSocket.port); WebSocket.console("Created socket on port " + WebSocket.port); while (true) { Socket s = ss.accept(); WebSocket.console("New Client connecting..."); WebSocket.handshakes.add(WebSocket.indexNum,false); WebSocket.nicknames.add(WebSocket.indexNum,""); WebSocket.channels.add(WebSocket.indexNum,""); WebSocketClient p = new WebSocketClient(s,WebSocket.indexNum); Thread t = new Thread( p); WebSocket.clients.add(WebSocket.indexNum,p); indexNum++; t.start(); } } catch (Exception e) { WebSocket.console("ERROR - " + e.toString()); } } public static void console(String msg) { Date date = new Date(); System.out.println("[" + date.toString() + "] " + msg); } } class WebSocketClient implements Runnable { private Socket s; private int iAm; private String socket_res = ""; private String socket_host = ""; private String socket_origin = ""; protected String nick = ""; protected String ircChan = ""; WebSocketClient(Socket socket, int mynum) { s = socket; iAm = mynum; } public void run() { String client = s.getInetAddress().toString(); WebSocket.console("Connection from " + client); IRCclient irc = new IRCclient(iAm); Thread t = new Thread( irc ); try { Scanner in = new Scanner(s.getInputStream()); PrintWriter out = new PrintWriter(s.getOutputStream(),true); while (true) { if (! in.hasNextLine()) continue; String input = in.nextLine().trim(); if (input.isEmpty()) continue; // Lets work out what's wrong with our input if (input.length() > 3 && input.charAt(0) == 65533) { input = input.substring(2); } WebSocket.console("< " + input); // Lets work out if they authenticate... if (WebSocket.handshakes.get(iAm) == false) { checkForHandShake(input); continue; } // Lets check for NICK: if (input.length() > 6 && input.substring(0,6).equals("NICK: ")) { nick = input.substring(6); Random generator = new Random(); int rand = generator.nextInt(); WebSocket.console("I am known as " + nick); WebSocket.nicknames.set(iAm, "bo-" + nick + rand); } if (input.length() > 9 && input.substring(0,9).equals("CHANNEL: ")) { ircChan = "bo-" + input.substring(9); WebSocket.console("We will be joining " + ircChan); WebSocket.channels.set(iAm, ircChan); } if (! ircChan.isEmpty() && ! nick.isEmpty() && irc.started == false) { irc.chan = ircChan; irc.nick = WebSocket.nicknames.get(iAm); t.start(); continue; } else { irc.msg(input); } } } catch (Exception e) { WebSocket.console(e.toString()); e.printStackTrace(); } t.stop(); WebSocket.channels.remove(iAm); WebSocket.clients.remove(iAm); WebSocket.handshakes.remove(iAm); WebSocket.nicknames.remove(iAm); WebSocket.console("Closing connection from " + client); } private void checkForHandShake(String input) { // Check for HTML5 Socket getHeaders(input); if (! socket_res.isEmpty() && ! socket_host.isEmpty() && ! socket_origin.isEmpty()) { send("HTTP/1.1 101 Web Socket Protocol Handshake\r\n" + "Upgrade: WebSocket\r\n" + "Connection: Upgrade\r\n" + "WebSocket-Origin: " + socket_origin + "\r\n" + "WebSocket-Location: ws://" + socket_host + "/\r\n\r\n",false); WebSocket.handshakes.set(iAm,true); } return; } private void getHeaders(String input) { if (input.length() >= 8 && input.substring(0,8).equals("Origin: ")) { socket_origin = input.substring(8); return; } if (input.length() >= 6 && input.substring(0,6).equals("Host: ")) { socket_host = input.substring(6); return; } if (input.length() >= 7 && input.substring(0,7).equals("Cookie:")) { socket_res = "."; } /*input = input.substring(4); socket_res = input.substring(0,input.indexOf(" HTTP")); input = input.substring(input.indexOf("Host:") + 6); socket_host = input.substring(0,input.indexOf("\r\n")); input = input.substring(input.indexOf("Origin:") + 8); socket_origin = input.substring(0,input.indexOf("\r\n"));*/ return; } protected void send(String msg, boolean newline) { byte c0 = 0x00; byte c255 = (byte) 0xff; try { PrintWriter out = new PrintWriter(s.getOutputStream(),true); WebSocket.console("> " + msg); if (newline == true) msg = msg + "\n"; out.print(msg + c255); out.flush(); } catch (Exception e) { WebSocket.console(e.toString()); } } protected void send(String msg) { try { WebSocket.console(">> " + msg); byte[] message = msg.getBytes(); byte[] newmsg = new byte[message.length + 2]; newmsg[0] = (byte)0x00; for (int i = 1; i <= message.length; i++) { newmsg[i] = message[i - 1]; } newmsg[message.length + 1] = (byte)0xff; // This prints correctly..., apparently... System.out.println(Arrays.toString(newmsg)); OutputStream socketOutputStream = s.getOutputStream(); socketOutputStream.write(newmsg); } catch (Exception e) { WebSocket.console(e.toString()); } } protected void send(String msg, boolean one, boolean two) { try { WebSocket.console(">> " + msg); byte[] message = msg.getBytes(); byte[] newmsg = new byte[message.length+1]; for (int i = 0; i < message.length; i++) { newmsg[i] = message[i]; } newmsg[message.length] = (byte)0xff; // This prints correctly..., apparently... System.out.println(Arrays.toString(newmsg)); OutputStream socketOutputStream = s.getOutputStream(); socketOutputStream.write(newmsg); } catch (Exception e) { e.printStackTrace(); } } } class IRCclient implements Runnable { protected String nick; protected String chan; protected int iAm; boolean started = false; IRCUser irc; IRCclient(int me) { iAm = me; irc = new IRCUser(iAm); } public void run() { WebSocket.console("Connecting to IRC..."); started = true; irc.setNick(nick); irc.setVerbose(false); irc.connectToIRC(chan); } void msg(String input) { irc.sendMessage("#" + chan, input); } } class IRCUser extends PircBot { int iAm; IRCUser(int me) { iAm = me; } public void setNick(String nick) { this.setName(nick); } public void connectToIRC(String chan) { try { this.connect("irc.appliedirc.com"); this.joinChannel("#" + chan); } catch (Exception e) { WebSocket.console(e.toString()); } } public void onMessage(String channel, String sender,String login, String hostname, String message) { // Lets send this message to me WebSocket.clients.get(iAm).send(message); } } Whenever I try to send the message to the browser (via Web Sockets), it complains that it doesn't start with 0x00 (which is a byte). Any ideas? Edit 19/02 - Added the entire code. I know it's real messy and not neat, but I want to get it functioning first. Spend last two days trying to fix.

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  • How do I make my USB Bluetooth dongle work in Ubuntu 11.04 ? (Can't init device hci0: Connection timed out (110)) [closed]

    - by MaikoID
    I've a USB bluetooth dongle root@maiko-cce-lin:~# lsusb | grep Bluetooth Bus 001 Device 007: ID 0a12:0001 Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode) that isn't working properly, hardly-ever it works but stops working in my next reboot. what I've tried it isn't software blocked root@maiko-cce-lin:~# rfkill list 0: phy0: Wireless LAN Soft blocked: no Hard blocked: no 1: hci0: Bluetooth Soft blocked: no Hard blocked: no my device is recognized by hciconfig root@maiko-cce-lin:~# hciconfig -a hci0: Type: BR/EDR Bus: USB BD Address: 00:1F:81:00:01:1C ACL MTU: 1021:4 SCO MTU: 180:1 DOWN RX bytes:330 acl:0 sco:0 events:8 errors:0 TX bytes:24 acl:0 sco:0 commands:30 errors:22 Features: 0xff 0x3e 0x09 0x76 0x80 0x01 0x00 0x80 Packet type: DM1 DM3 DM5 DH1 DH3 DH5 HV1 HV2 HV3 Link policy: Link mode: SLAVE ACCEPT but I can't turn on my hci interface root@maiko-cce-lin:~# hciconfig hci up Can't init device hci0: Connection timed out (110) I don't understand why.. the hcitool command doesn't show any device. root@maiko-cce-lin:~# hcitool dev Devices: I've tried to restart my bluetooth service too with this command and make all these previous commands again but without success. root@maiko-cce-lin:~# service bluetooth restart * Stopping bluetooth [ OK ] * Starting bluetooth [ OK ] root@maiko-cce-lin:~# The dongle works if you disconnect it from usb, wait a few seconds and connect it again. so there must be better solution for it ( a solution not involving physically removing the dongle!)

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  • Visual Basic Cryptography Question

    - by Glenn Sullivan
    I am trying to mimic the results of some C code that uses the OpenSSL library using the system.security.crytography library in the .net 3.5 world, and I can't seem to get it right. I need some help... part of the issue is my understanding of crytography in general. Here's what is supposed to happen: I send a request for authentication to a device. It returns a challenge digest, which I then need to sign with a known key and return The device returns a "success" or "Fail" message. I have the following code snippet that I am trying to "copy": //Seed the PRNG //Cheating here - the PRNG will be seeded when we create a key pair //The key pair is discarded only doing this to seed the PRNG. DSA *temp_dsa = DSA_new(); if(!temp_dsa) { printf("Error: The client had an error with the DSA API\n"); exit(0); } unsigned char seed[20] = "Our Super Secret Key"; temp_dsa = DSA_generate_parameters(128, seed, sizeof(seed), NULL, NULL, NULL, NULL); DSA_free(temp_dsa); //A pointer to the private key. p = (unsigned char *)&priv_key; //Create and allocate a DSA structure from the private key. DSA *priv_dsa = NULL; priv_dsa = d2i_DSAPrivateKey(NULL, &p, sizeof(priv_key)); if(!priv_dsa) { printf("Error: The client had an error with the DSA API\n"); exit(0); } //Allocate memory for the to be computed signature. sigret = OPENSSL_malloc(DSA_size(priv_dsa)); //Sign the challenge digest recieved from the ISC. retval = DSA_sign(0, pResp->data, pResp->data_length, sigret, &siglen, priv_dsa); A few more bits of information: priv_key is a 252 element character array of hex characters that is included. The end result is a 512 (or less) array of characters to send back for validation to the device. Rasmus asked to see the key array. Here it is: unsigned char priv_key[] = {0x30, 0x81, 0xf9, 0x02, 0x01, 0x00, 0x02, 0x41, 0x00, 0xfe, 0xca, 0x97, 0x55, 0x1f, 0xc0, 0xb7, 0x1f, 0xad, 0xf0, 0x93, 0xec, 0x4b, 0x31, 0x94, 0x78, 0x86, 0x82, 0x1b, 0xab, 0xc4, 0x9e, 0x5c, 0x40, 0xd9, 0x89, 0x7d, 0xde, 0x43, 0x38, 0x06, 0x4f, 0x1b, 0x2b, 0xef, 0x5c, 0xb7, 0xff, 0x21, 0xb1, 0x11, 0xe6, 0x9a, 0x81, 0x9a, 0x2b, 0xef, 0x3a, 0xbb, 0x5c, 0xea, 0x76, 0xae, 0x3a, 0x8b, 0x92, 0xd2, 0x7c, 0xf1, 0x89, 0x8e, 0x4d, 0x3f, 0x0d, 0x02, 0x15, 0x00, 0x88, 0x16, 0x1b, 0xf5, 0xda, 0x43, 0xee, 0x4b, 0x58, 0xbb, 0x93, 0xea, 0x4e, 0x2b, 0xda, 0xb9, 0x17, 0xd1, 0xff, 0x21, 0x02, 0x41, 0x00, 0xf6, 0xbb, 0x45, 0xea, 0xda, 0x72, 0x39, 0x4f, 0xc1, 0xdd, 0x02, 0xb4, 0xf3, 0xaa, 0xe5, 0xe2, 0x76, 0xc7, 0xdc, 0x34, 0xb2, 0x0a, 0xd8, 0x69, 0x63, 0xc3, 0x40, 0x2c, 0x58, 0xea, 0xa6, 0xbd, 0x24, 0x8b, 0x6b, 0xaa, 0x4b, 0x41, 0xfc, 0x5f, 0x21, 0x02, 0x3c, 0x27, 0xa9, 0xc7, 0x7a, 0xc8, 0x59, 0xcd, 0x5b, 0xdd, 0x6c, 0x44, 0x48, 0x86, 0xd1, 0x34, 0x46, 0xb0, 0x89, 0x55, 0x50, 0x87, 0x02, 0x41, 0x00, 0x80, 0x29, 0xc6, 0x4a, 0x08, 0x3e, 0x30, 0x54, 0x71, 0x9b, 0x95, 0x49, 0x55, 0x17, 0x70, 0xc7, 0x96, 0x65, 0xc8, 0xc2, 0xe2, 0x8a, 0xe0, 0x5d, 0x9f, 0xe4, 0xb2, 0x1f, 0x20, 0x83, 0x70, 0xbc, 0x88, 0x36, 0x03, 0x29, 0x59, 0xcd, 0xc7, 0xcd, 0xd9, 0x4a, 0xa8, 0x65, 0x24, 0x6a, 0x77, 0x8a, 0x10, 0x88, 0x0d, 0x2f, 0x15, 0x4b, 0xbe, 0xba, 0x13, 0x23, 0xa1, 0x73, 0xa3, 0x04, 0x37, 0xc9, 0x02, 0x14, 0x06, 0x8e, 0xc1, 0x41, 0x40, 0xf1, 0xf6, 0xe1, 0xfa, 0xfb, 0x64, 0x28, 0x02, 0x15, 0xce, 0x47, 0xaa, 0xce, 0x6e, 0xfe}; Can anyone help me translate this code to it's VB.net crypto equivalent? TIA, Glenn

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  • Simplex Noise Help

    - by Alex Larsen
    Im Making A Minecraft Like Gae In XNA C# And I Need To Generate Land With Caves This Is The Code For Simplex I Have /// <summary> /// 1D simplex noise /// </summary> /// <param name="x"></param> /// <returns></returns> public static float Generate(float x) { int i0 = FastFloor(x); int i1 = i0 + 1; float x0 = x - i0; float x1 = x0 - 1.0f; float n0, n1; float t0 = 1.0f - x0 * x0; t0 *= t0; n0 = t0 * t0 * grad(perm[i0 & 0xff], x0); float t1 = 1.0f - x1 * x1; t1 *= t1; n1 = t1 * t1 * grad(perm[i1 & 0xff], x1); // The maximum value of this noise is 8*(3/4)^4 = 2.53125 // A factor of 0.395 scales to fit exactly within [-1,1] return 0.395f * (n0 + n1); } /// <summary> /// 2D simplex noise /// </summary> /// <param name="x"></param> /// <param name="y"></param> /// <returns></returns> public static float Generate(float x, float y) { const float F2 = 0.366025403f; // F2 = 0.5*(sqrt(3.0)-1.0) const float G2 = 0.211324865f; // G2 = (3.0-Math.sqrt(3.0))/6.0 float n0, n1, n2; // Noise contributions from the three corners // Skew the input space to determine which simplex cell we're in float s = (x + y) * F2; // Hairy factor for 2D float xs = x + s; float ys = y + s; int i = FastFloor(xs); int j = FastFloor(ys); float t = (float)(i + j) * G2; float X0 = i - t; // Unskew the cell origin back to (x,y) space float Y0 = j - t; float x0 = x - X0; // The x,y distances from the cell origin float y0 = y - Y0; // For the 2D case, the simplex shape is an equilateral triangle. // Determine which simplex we are in. int i1, j1; // Offsets for second (middle) corner of simplex in (i,j) coords if (x0 > y0) { i1 = 1; j1 = 0; } // lower triangle, XY order: (0,0)->(1,0)->(1,1) else { i1 = 0; j1 = 1; } // upper triangle, YX order: (0,0)->(0,1)->(1,1) // A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and // a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where // c = (3-sqrt(3))/6 float x1 = x0 - i1 + G2; // Offsets for middle corner in (x,y) unskewed coords float y1 = y0 - j1 + G2; float x2 = x0 - 1.0f + 2.0f * G2; // Offsets for last corner in (x,y) unskewed coords float y2 = y0 - 1.0f + 2.0f * G2; // Wrap the integer indices at 256, to avoid indexing perm[] out of bounds int ii = i % 256; int jj = j % 256; // Calculate the contribution from the three corners float t0 = 0.5f - x0 * x0 - y0 * y0; if (t0 < 0.0f) n0 = 0.0f; else { t0 *= t0; n0 = t0 * t0 * grad(perm[ii + perm[jj]], x0, y0); } float t1 = 0.5f - x1 * x1 - y1 * y1; if (t1 < 0.0f) n1 = 0.0f; else { t1 *= t1; n1 = t1 * t1 * grad(perm[ii + i1 + perm[jj + j1]], x1, y1); } float t2 = 0.5f - x2 * x2 - y2 * y2; if (t2 < 0.0f) n2 = 0.0f; else { t2 *= t2; n2 = t2 * t2 * grad(perm[ii + 1 + perm[jj + 1]], x2, y2); } // Add contributions from each corner to get the final noise value. // The result is scaled to return values in the interval [-1,1]. return 40.0f * (n0 + n1 + n2); // TODO: The scale factor is preliminary! } public static float Generate(float x, float y, float z) { // Simple skewing factors for the 3D case const float F3 = 0.333333333f; const float G3 = 0.166666667f; float n0, n1, n2, n3; // Noise contributions from the four corners // Skew the input space to determine which simplex cell we're in float s = (x + y + z) * F3; // Very nice and simple skew factor for 3D float xs = x + s; float ys = y + s; float zs = z + s; int i = FastFloor(xs); int j = FastFloor(ys); int k = FastFloor(zs); float t = (float)(i + j + k) * G3; float X0 = i - t; // Unskew the cell origin back to (x,y,z) space float Y0 = j - t; float Z0 = k - t; float x0 = x - X0; // The x,y,z distances from the cell origin float y0 = y - Y0; float z0 = z - Z0; // For the 3D case, the simplex shape is a slightly irregular tetrahedron. // Determine which simplex we are in. int i1, j1, k1; // Offsets for second corner of simplex in (i,j,k) coords int i2, j2, k2; // Offsets for third corner of simplex in (i,j,k) coords /* This code would benefit from a backport from the GLSL version! */ if (x0 >= y0) { if (y0 >= z0) { i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 1; k2 = 0; } // X Y Z order else if (x0 >= z0) { i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 0; k2 = 1; } // X Z Y order else { i1 = 0; j1 = 0; k1 = 1; i2 = 1; j2 = 0; k2 = 1; } // Z X Y order } else { // x0<y0 if (y0 < z0) { i1 = 0; j1 = 0; k1 = 1; i2 = 0; j2 = 1; k2 = 1; } // Z Y X order else if (x0 < z0) { i1 = 0; j1 = 1; k1 = 0; i2 = 0; j2 = 1; k2 = 1; } // Y Z X order else { i1 = 0; j1 = 1; k1 = 0; i2 = 1; j2 = 1; k2 = 0; } // Y X Z order } // A step of (1,0,0) in (i,j,k) means a step of (1-c,-c,-c) in (x,y,z), // a step of (0,1,0) in (i,j,k) means a step of (-c,1-c,-c) in (x,y,z), and // a step of (0,0,1) in (i,j,k) means a step of (-c,-c,1-c) in (x,y,z), where // c = 1/6. float x1 = x0 - i1 + G3; // Offsets for second corner in (x,y,z) coords float y1 = y0 - j1 + G3; float z1 = z0 - k1 + G3; float x2 = x0 - i2 + 2.0f * G3; // Offsets for third corner in (x,y,z) coords float y2 = y0 - j2 + 2.0f * G3; float z2 = z0 - k2 + 2.0f * G3; float x3 = x0 - 1.0f + 3.0f * G3; // Offsets for last corner in (x,y,z) coords float y3 = y0 - 1.0f + 3.0f * G3; float z3 = z0 - 1.0f + 3.0f * G3; // Wrap the integer indices at 256, to avoid indexing perm[] out of bounds int ii = i % 256; int jj = j % 256; int kk = k % 256; // Calculate the contribution from the four corners float t0 = 0.6f - x0 * x0 - y0 * y0 - z0 * z0; if (t0 < 0.0f) n0 = 0.0f; else { t0 *= t0; n0 = t0 * t0 * grad(perm[ii + perm[jj + perm[kk]]], x0, y0, z0); } float t1 = 0.6f - x1 * x1 - y1 * y1 - z1 * z1; if (t1 < 0.0f) n1 = 0.0f; else { t1 *= t1; n1 = t1 * t1 * grad(perm[ii + i1 + perm[jj + j1 + perm[kk + k1]]], x1, y1, z1); } float t2 = 0.6f - x2 * x2 - y2 * y2 - z2 * z2; if (t2 < 0.0f) n2 = 0.0f; else { t2 *= t2; n2 = t2 * t2 * grad(perm[ii + i2 + perm[jj + j2 + perm[kk + k2]]], x2, y2, z2); } float t3 = 0.6f - x3 * x3 - y3 * y3 - z3 * z3; if (t3 < 0.0f) n3 = 0.0f; else { t3 *= t3; n3 = t3 * t3 * grad(perm[ii + 1 + perm[jj + 1 + perm[kk + 1]]], x3, y3, z3); } // Add contributions from each corner to get the final noise value. // The result is scaled to stay just inside [-1,1] return 32.0f * (n0 + n1 + n2 + n3); // TODO: The scale factor is preliminary! } private static byte[] perm = new byte[512] { 151,160,137,91,90,15, 131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23, 190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33, 88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166, 77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244, 102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196, 135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123, 5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42, 223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9, 129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228, 251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107, 49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254, 138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180, 151,160,137,91,90,15, 131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23, 190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33, 88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166, 77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244, 102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196, 135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123, 5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42, 223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9, 129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228, 251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107, 49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254, 138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180 }; private static int FastFloor(float x) { return (x > 0) ? ((int)x) : (((int)x) - 1); } private static float grad(int hash, float x) { int h = hash & 15; float grad = 1.0f + (h & 7); // Gradient value 1.0, 2.0, ..., 8.0 if ((h & 8) != 0) grad = -grad; // Set a random sign for the gradient return (grad * x); // Multiply the gradient with the distance } private static float grad(int hash, float x, float y) { int h = hash & 7; // Convert low 3 bits of hash code float u = h < 4 ? x : y; // into 8 simple gradient directions, float v = h < 4 ? y : x; // and compute the dot product with (x,y). return ((h & 1) != 0 ? -u : u) + ((h & 2) != 0 ? -2.0f * v : 2.0f * v); } private static float grad(int hash, float x, float y, float z) { int h = hash & 15; // Convert low 4 bits of hash code into 12 simple float u = h < 8 ? x : y; // gradient directions, and compute dot product. float v = h < 4 ? y : h == 12 || h == 14 ? x : z; // Fix repeats at h = 12 to 15 return ((h & 1) != 0 ? -u : u) + ((h & 2) != 0 ? -v : v); } private static float grad(int hash, float x, float y, float z, float t) { int h = hash & 31; // Convert low 5 bits of hash code into 32 simple float u = h < 24 ? x : y; // gradient directions, and compute dot product. float v = h < 16 ? y : z; float w = h < 8 ? z : t; return ((h & 1) != 0 ? -u : u) + ((h & 2) != 0 ? -v : v) + ((h & 4) != 0 ? -w : w); } This Is My World Generation Code Block[,] BlocksInMap = new Block[1024, 256]; public bool IsWorldGenerated = false; Random r = new Random(); private void RunThread() { for (int BH = 0; BH <= 256; BH++) { for (int BW = 0; BW <= 1024; BW++) { Block b = new Block(); if (BH >= 192) { } BlocksInMap[BW, BH] = b; } } IsWorldGenerated = true; } public void GenWorld() { new Thread(new ThreadStart(RunThread)).Start(); } And This Is A Example Of How I Set Blocks Block b = new Block(); b.BlockType = = Block.BlockTypes.Air; This Is A Example Of How I Set Models foreach (Block b in MyWorld) { switch(b.BlockType) { case Block.BlockTypes.Dirt: b.Model = DirtModel; break; ect. } } How Would I Use These To Generate To World (The Block Array) And If Possible Thread It More? btw It's 1024 Wide And 256 Tall

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  • USB Serial cable with CDC support

    - by Harsha
    Hi All, I bought a USB to Serial cable which claims to be CDC compliant. But the bInterfaceClass value in interface descriptor is 0xFF(which is vendor specific). I was expecting it to be 0x02 (Communications and CDC control). In the device manager, i found that the drivers being loaded are ser2pl.sys and serenum.sys. I had learnt usbser.sys is the windows CDC driver, but it was not loaded for my cable. I am pretty much new to this CDC, so i have following questions 1.Does this indicate that the cable is not CDC compliant 2.Can i make this cable CDC compliant (since CDC is a driver functionality), by loading usbser.sys. If yes how?

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  • UART speed possibly wrong

    - by Mike
    My brain is fried, so I thought I would pass this one to the community. When sending 1 character to my embedded system, it consistently thinks it receives 2 characters. The first received character seems to map to the transmitted character (in some unkown way) and the second received character is always 0xff Here is what I observed: Tx char (in hex) Rx character (in hex), I left out the second byte (always ff) 31 9D 32 9B 33 99 61 3D 62 3B 63 39 64 37 65 35 41 7D 42 7B 43 79 I have check my clocks and them seem to be ok. The only diff between this non working version and the previous version is that i am now using a RS485 chip. I have traced the signal all the way up to the MCU and it looks fine (confirmed the bit value on the rx pin)

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  • USB enumeration failure in ColdFire MCF52259

    - by Quicksilver
    Anybody with programming experience on the ColdFire line, please help! I'm using the CMX USB-Lite stack with the ColdFire MCF52259. For some reason, USB enumeration fails at the very first step, as soon as I enable the DP pull-up resistor. This is what I'm doing :- INT_ENB, OTG_INT_EN, ERR_ENB are set to 0x0 INT_STAT, OTG_INT_STAT and ERR_STAT are set to 0xff (This should clear all interrupts) In the Interrupt Status Register, bits 0 (Mask All) and 53 are made 0, all others are 1. TOK_DNE, USB_RST and STALL interrupts are enabled in INT_ENB. BDT base address is set. MCF_USB_CTL holds 0x1 PROBLEM: After the host issues the first reset (at which point I enable Control endpoint 0), instead of the expected Get Descriptor request I'm getting an endless series of resets. At least, that's what it looks like, because the TOK_DNE interrupt never triggers. Is there anything I'm doing wrong?

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  • How to decode numeric HTML entities in PHP

    - by Yuriy
    Hello, I'm trying to decode encoded long dash from numeric entity to string, but it seems that I can't find a function which can do this properly. The best that I found is mb_decode_numericentity(), however, for some reason it fails to decode long dash and some other special characters. $str = '–'; // <- ' & # 8211 ;' $str = mb_decode_numericentity ( $str , Array(0xFF, 0x2FFFF, 0, 0xFFFF) , 'ISO-8859-1'); This will return "?". Anyone knows how to solve this problem?

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  • Convert an array of bytes into one decimal number as a string

    - by Martin Kirsche
    I'm trying to write function that converts an arbitrary large array of bytes (larger than 64-bit) into a decimal number represented as string in c# and I simply can't figure out how to do it. For example the following code ... Console.WriteLine(ConvertToString( new byte[] { 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF, 0x00 })); .. should print out 22774453838368691933757882222884355840 I don't want to just use an extra library like biginteger for that, because I want it to be simple and like to understand how it works.

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  • Some special characters defined in "ISO-8859-1" can't be shown when encoding with "UTF-8"

    - by Mike.Huang
    I need to get a string from URL request of brower, and then create a text image by requested text. I know the default encoding of the Java net transmission is "ISO-8859-1", it can works normally with all characters what defined in "ISO-8859-1". But when I request a multi-byte Unicode character (e.g. chinese or something like ¤?), then I need to decode it by "UTF-8" from "ISO-8859-1". My codes like: String reslut = new String(requestString.getBytes("ISO-8859-1"), "UTF-8"); Everything is fine, but I found some characters in ISO-8859-1 are not been shown now, which characters are 0x80 - 0xFF(defined in" ISO-8859-1"), i.e. the characters after 0x80 (in "ISO-8859-1") not been shown when converted to "UTF-8" from "ISO-8859-1". Any other method can solve this query?

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  • How to hide the label (CCLabel) after a certain time in cocos2d ?

    - by srikanth rongali
    I added a label by using CCLabel to my layer. Now I want it do disappear after some time like (2sec). How can I make it to disappear? CCLabel *labelPerfectDraw = [CCLabel labelWithString:@"Perfect Draw" fontName:@"Marker Felt" fontSize:30 ]; labelPerfectDraw.color = ccc3(0x00, 0x00, 0xff); labelPerfectDraw.position = ccp(windowSize.width/2, windowSize.height/2+80); [self addChild:labelPerfectDraw]; I added label in above way. Please give me the idea how can I work on it?

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  • AVR Analog Comparator + Internal Pullup?

    - by vicatcu
    I have what I hope is a simple question pertaining to the Atmel AVR microcontrollers. So I want to use the ATTiny85's Analog Comparator to determine if a signal is above or below a threshold. This signal is normally "floating" and grounded when "active" (i.e. it's an active low - open collector signal). If I enable the pullup on the input pin (which is also the comparator input) by doing: DDRB = 0x00; // DDRB.1 = 0 = input PORTB = 0xFF; // PORTB.1 = 1 = internal pullup enabled If i use the analog comparator and select PORTB.1 as AIN1 will the internal pullup be applied to my input signal? I'm hoping someone has personal experience to verify this behavior. Hope this question isn't too 'hardware-oriented' for stack-overflow. Thanks!

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  • How do you control what your C compiler Optimizes?

    - by Jordan S
    I am writing the firmware for an embedded device in C using the Silicon Labs IDE and the SDCC compiler. The device architecture is based on the 8051 family. The function in question is shown below. The function is used to set the ports on my MCU to drive a stepper motor. It gets called in by an interrupt handler. The big switch statement just sets the ports to the proper value for the next motor step. The bottom part of the function looks at an input from a hall effect sensor and a number of steps moved in order to detect if the motor has stalled. The problem is, for some reason the second IF statement that looks like this if (StallDetector > (GapSize + 20)) { HandleStallEvent(); } always seems to get optimized out. If I try to put a breakpoint at the HandleStallEvent() call the IDE gives me a message saying "No Address Correlation to this line number". I am not really good enough at reading assembly to tell what it is doing but I have pasted a snippet from the asm output below. Any help would be much appreciated. void OperateStepper(void) { //static bit LastHomeMagState = HomeSensor; static bit LastPosMagState = PosSensor; if(PulseMotor) { if(MoveDirection == 1) // Go clockwise { switch(STEPPER_POSITION) { case 'A': STEPPER_POSITION = 'B'; P1 = 0xFD; break; case 'B': STEPPER_POSITION = 'C'; P1 = 0xFF; break; case 'C': STEPPER_POSITION = 'D'; P1 = 0xFE; break; case 'D': STEPPER_POSITION = 'A'; P1 = 0xFC; break; default: STEPPER_POSITION = 'A'; P1 = 0xFC; } //end switch } else // Go CounterClockwise { switch(STEPPER_POSITION) { case 'A': STEPPER_POSITION = 'D'; P1 = 0xFE; break; case 'B': STEPPER_POSITION = 'A'; P1 = 0xFC; break; case 'C': STEPPER_POSITION = 'B'; P1 = 0xFD; break; case 'D': STEPPER_POSITION = 'C'; P1 = 0xFF; break; default: STEPPER_POSITION = 'A'; P1 = 0xFE; } //end switch } //end else MotorSteps++; StallDetector++; if(PosSensor != LastPosMagState) { StallDetector = 0; LastPosMagState = PosSensor; } else { if (PosSensor == ON) { if (StallDetector > (MagnetSize + 20)) { HandleStallEvent(); } } else if (PosSensor == OFF) { if (StallDetector > (GapSize + 20)) { HandleStallEvent(); } } } } //end if PulseMotor } ... and the asm output for the the bottom part of this function... ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:653: if(PosSensor != LastPosMagState) mov c,_P1_4 jb _OperateStepper_LastPosMagState_1_1,00158$ cpl c 00158$: jc 00126$ C$MotionControl.c$655$3$7 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:655: StallDetector = 0; clr a mov _StallDetector,a mov (_StallDetector + 1),a C$MotionControl.c$657$3$7 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:657: LastPosMagState = PosSensor; mov c,_P1_4 mov _OperateStepper_LastPosMagState_1_1,c ret 00126$: C$MotionControl.c$661$2$8 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:661: if (PosSensor == ON) jb _P1_4,00123$ C$MotionControl.c$663$4$9 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:663: if (StallDetector > (MagnetSize + 20)) mov a,_MagnetSize mov r2,a rlc a subb a,acc mov r3,a mov a,#0x14 add a,r2 mov r2,a clr a addc a,r3 mov r3,a clr c mov a,r2 subb a,_StallDetector mov a,r3 subb a,(_StallDetector + 1) jnc 00130$ C$MotionControl.c$665$5$10 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:665: HandleStallEvent(); ljmp _HandleStallEvent 00123$: C$MotionControl.c$668$2$8 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:668: else if (PosSensor == OFF) jnb _P1_4,00130$ C$MotionControl.c$670$4$11 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:670: if (StallDetector > (GapSize + 20)) mov a,#0x14 add a,_GapSize mov r2,a clr a addc a,(_GapSize + 1) mov r3,a clr c mov a,r2 subb a,_StallDetector mov a,r3 subb a,(_StallDetector + 1) jnc 00130$ C$MotionControl.c$672$5$12 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:672: HandleStallEvent(); C$MotionControl.c$678$2$1 ==. XG$OperateStepper$0$0 ==. ljmp _HandleStallEvent 00130$: ret It looks to me like the compiler is NOT optimizing out this second if statement from the looks of the asm but if that is the case why does the IDE not allow me so set a breakpoint there? Maybe it's just a dumb IDE!

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  • Is there any sense in performing binary AND with a number where all bits are set to 1

    - by n535
    Greetings everybody. I have seen examples of such operations for so many times that I begin to think that I am getting something wrong with binary arithmetic. Is there any sense to perform the following: byte value = someAnotherByteValue & 0xFF; I don't really understand this, because it does not change anything anyway. Thanks for help. P.S. I was trying to search for information both elsewhere and here, but unsuccessfully. EDIT: Well, off course i assume that someAnotherByteValue is 8 bits long, the problem is that i don't get why so many people ( i mean professionals ) use such things in their code. For example in Jon Skeet's MiscUtil there is: uint s1 = (uint)(initial & 0xffff); where initial is int.

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  • How to draw Wingdings 2 characters outside of the 0..255 range in .NET?

    - by romkyns
    The standard windows Charmap utility shows quite a few characters in the "Wingdings 2" font whose character codes are greater than 255 - for example, 0xE4E shows a hand. However, if I try to draw these characters as follows: g.DrawString(new string((char) 0xE4E, 1), new Font("Wingdings 2", 20), brush, x, y); then all I get is a standard "box" replacement character. This is weird, because the above code works for Wingdings 2 symbols between 0x21 and 0xFF, and also works for ALL symbols in, say, Arial Unicode MS. How can I draw those characters from this particular font? Is there a separate API? (Win7; .NET 3.5 SP1) P.S. Here's the weird Character Map font with the duplicated character ranges:

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