最近使用海康威视的5寸一体化智能球，查阅些SDK, 在Winform中海康威视能较好的集成，但是对于Yv12编解码和实时视频流的支持未找到较好的SDK介绍。
因为项目需要是用在XNA游戏框架中，本身有自己的消息处理机制，集成海康威视有些复杂。在结合Goblin XNA、DirectShow的基础上，查询和测试了相关的算法，给出下面的解码方式，分享给遇到同样问题的博友。
具体的SDK引用和DecFunctionEvent事件触发比较简单，请查阅海康威视官方样例中自定义视频流的RealDataCallBack中的PlayCtrl.DECCBFUN。
（CH-HCNetSDK(Windows32)V4.2.8.1_5目录中的“实时预览示例代码”等）
以下两个类的重点在GetImageTexture和_yv12ToRgb.ConvertToInt解码方法，以获取到Goblin Scene中int[] returnImage（每个int为color的packedValue，由RGB移位生成， rgb24[index++] = (int)(rgb[0]<<16 | rgb[1]<<8 | rgb[2]);）
各值 rgb[2] = py + rdif;
//R
rgb[1] = py -
invgdif;
//G
rgb[0] = py +
bdif; //B
1. 设备类-HkwsCapture.cs
使用Goblin的scene.AddVideoCaptureDevice(captureDevice)加载
using System;
using System.Collections;
using
System.Collections.Generic;
using System.Drawing;
using
System.Text;
using System.IO;
using System.Reflection;
using
CameraWrapper.VideoCapture;
using GoblinXNA.Device.Capture;
using
Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using
System.Runtime.InteropServices;
using DShowNET;
using
DShowNET.Device;
using GoblinXNA;
using GoblinXNA.Device;
namespace MkcXNALibrary.VideoLib
{
public class
HkwsCapture : ISampleGrabberCB, IVideoCapture
{
private enum
PlaybackState
{
Stopped,
Paused,
Running,
Init
}
#region Member
Fields
private int
cameraWidth;
private int
cameraHeight;
private bool
grayscale;
private bool
cameraInitialized;
private
Resolution resolution;
private
FrameRate frameRate;
private
ImageFormat format;
private ImageReadyCallback imageReadyCallback;
private volatile PlaybackState playbackState = PlaybackState.Stopped;
private IntPtr grabbedImage;
private String selectedVideoDeviceName;
///
<summary>
/// Used to count
the number of times it failed to capture an
image
/// If it fails more than
certain times, it will assume that the
video
/// capture device can not
be accessed
///
</summary>
private int
failureCount;
private const int FAILURE_THRESHOLD = 1000;
private bool _processing = false,
_previewUpdating = false;
private
YV12ToRGB _yv12ToRgb;
readonly CameraInitInfo
_initInfo;
ICameraCapture
_currentCamera = new HikCapture();
#endregion
#region Constructors
///
<summary>
/// Creates a
video capture using the DirectShow
library.
///
</summary>
public
HkwsCapture(CameraInitInfo
cameraInfo)
{
cameraInitialized =
false;
grabbedImage = IntPtr.Zero;
cameraWidth =
0;
cameraHeight =
0;
grayscale = false;
_initInfo
=
cameraInfo;
failureCount = 0;
}
#endregion
#region Properties
public int
Width
{
get {
return cameraWidth; }
}
public int
Height
{
get {
return cameraHeight; }
}
public int VideoDeviceID { get; private set; }
public bool
GrayScale
{
get {
return grayscale; }
}
public bool
Initialized
{
get {
return cameraInitialized; }
}
public ImageFormat
Format
{
get {
return format; }
}
public IResizer MarkerTrackingImageResizer { get; set; }
public SpriteEffects
RenderFormat
{
get {
return SpriteEffects.None; }
}
///
<summary>
/// Sets the
callback function to be called when a new image becomes
ready.
///
</summary>
public
ImageReadyCallback CaptureCallback
{
set {
imageReadyCallback = value; }
}
#endregion
#region Public
Methods
public void
InitVideoCapture(int videoDeviceID, FrameRate framerate, Resolution
resolution,
ImageFormat format, bool
grayscale)
{
if
(cameraInitialized)
return;
this.resolution =
resolution;
this.grayscale =
grayscale;
this.frameRate =
framerate;
this.format = format;
switch
(resolution)
{
case
Resolution._160x120:
cameraWidth =
160;
cameraHeight =
120;
break;
case
Resolution._320x240:
cameraWidth =
320;
cameraHeight =
240;
break;
case
Resolution._640x480:
cameraWidth =
640;
cameraHeight =
480;
break;
case
Resolution._800x600:
cameraWidth =
800;
cameraHeight =
600;
break;
case
Resolution._1024x768:
cameraWidth =
1024;
cameraHeight =
768;
break;
case
Resolution._1280x1024:
cameraWidth =
1280;
cameraHeight =
1024;
break;
case
Resolution._1600x1200:
cameraWidth =
1600;
cameraHeight =
1200;
break;
case
Resolution._1280x720:
cameraWidth =
1280;
cameraHeight =
720;
break;
}
if
(!DsUtils.IsCorrectDirectXVersion())
throw new GoblinException("DirectX 8.1 NOT installed!");
var result
=
_currentCamera.Init(_initInfo);
if
(!string.IsNullOrEmpty(result))
throw new GoblinException(result);
_currentCamera.StartPreview(IntPtr.Zero);
_currentCamera.DecFunctionEvent += new
EventHandler<CameraWrapper.HkwsAPI.HkwsIPC.EventArgsStreamVideo>(_currentCamera_DecFunctionEvent);
_yv12ToRgb = new YV12ToRGB(cameraWidth,
cameraHeight);
cameraInitialized = true;
}
void
_currentCamera_DecFunctionEvent(object sender,
CameraWrapper.HkwsAPI.HkwsIPC.EventArgsStreamVideo
e)
{
if
(_processing)
return;
grabbedImage = e.Buffer;
}
private int count =
0;
public void
GetImageTexture(int[] returnImage, ref IntPtr
imagePtr)
{
if
(grabbedImage !=
IntPtr.Zero)
{
failureCount =
0;
_processing = true;
bool replaceBackground =
false;
if (imageReadyCallback !=
null)
replaceBackground = imageReadyCallback(grabbedImage, returnImage);
if ((returnImage != null) &&
!replaceBackground)
{
if
(!_previewUpdating)
{
_previewUpdating =
true;
_yv12ToRgb.ConvertToInt(grabbedImage, ref
returnImage);
_previewUpdating =
!_previewUpdating;
count++;
}
}
_processing
= false;
}
else
{
failureCount++;
if (failureCount >
FAILURE_THRESHOLD)
{
throw new GoblinException("Video capture device ID: HK IP " + ", Name: "
+
selectedVideoDeviceName + " is used by "
+
"other application, and can not be
accessed");
}
}
}
public void
Dispose()
{
}
///
<summary>
/// When you are
ready to convert the byte array back
/// to an image, you can include
the following code in your method.
///
</summary>
/// <param
name="myByteArray"></param>
///
<returns></returns>
public static Image ConvertByteArrayToImage(byte[]
myByteArray)
{
System.Drawing.Image
newImage;
using (MemoryStream ms = new MemoryStream(myByteArray, 0,
myByteArray.Length))
{
ms.Write(myByteArray, 0, myByteArray.Length);
newImage = Image.FromStream(ms, true);
// work with image here.
// You‘ll need to keep the MemoryStream open for
// as long as you want to work with your new image.
return
newImage;
}
}
#endregion
#region ISampleGrabberCB
Members
///
<summary>
/// Buffer
Callback method from the DirectShow.NET ISampleGrabberCB interface.
This method is called
/// when a
new frame is grabbed by the
SampleGrabber.
///
</summary>
/// <param
name="SampleTime">The sample
time.</param>
/// <param
name="pBuffer">A pointer to the image buffer that contains the grabbed
sample.</param>
///
<param name="BufferLen">The length of the image buffer containing the
grabbed sample.</param>
///
<returns>0 =
success.</returns>
public
int BufferCB(double SampleTime, IntPtr pBuffer, int
BufferLen)
{
while
(_processing) {
}
grabbedImage =
pBuffer;
return 0;
}
///
<summary>
/// Sample
CallBack method from the ISampleGrabberCB interface (DirectShow.NET). Not
used.
///
</summary>
/// <param
name="SampleTime"></param>
/// <param
name="pSample"></param>
///
<returns></returns>
public int SampleCB(double SampleTime, IMediaSample
pSample)
{
throw
new GoblinException("The method or operation is not
implemented.");
}
#endregion
}
}
2-YV12ToRGB.cs
using System;
using System.Collections.Generic;
using
System.Linq;
using System.Text;
using System.Drawing;
using
System.IO;
namespace MkcXNALibrary.VideoLib
{
public class
YV12ToRGB
{
private int width;
private int
height;
private int
length;
private int v;
//v值的起始位置
private int u;
//u值的起始位置
private int rdif,
invgdif, bdif;
private int[]
Table_fv1;
private int[]
Table_fv2;
private int[]
Table_fu1;
private int[]
Table_fu2;
private int[] rgb = new
int[3];
private int m, n, i, j,
hfWidth;
private bool addHalf =
true;
private int
py;
private int pos,
pos1;//图像调整
private byte temp;
static double[,] YUV2RGB_CONVERT_MATRIX = new double[3, 3] { { 1, 0, 1.4022 }, { 1, -0.3456, -0.7145 }, { 1, 1.771, 0 } };
public YV12ToRGB(int iWidth, int
iHeight)
{
Table_fv1 = new int[256] { -180, -179, -177, -176, -174, -173, -172, -170, -169,
-167, -166, -165, -163, -162, -160, -159, -158, -156, -155, -153, -152, -151,
-149, -148, -146, -145, -144, -142, -141, -139, -138, -137, -135, -134, -132,
-131, -130, -128, -127, -125, -124, -123, -121, -120, -118, -117, -115, -114,
-113, -111, -110, -108, -107, -106, -104, -103, -101, -100, -99, -97, -96, -94,
-93, -92, -90, -89, -87, -86, -85, -83, -82, -80, -79, -78, -76, -75, -73, -72,
-71, -69, -68, -66, -65, -64, -62, -61, -59, -58, -57, -55, -54, -52, -51, -50,
-48, -47, -45, -44, -43, -41, -40, -38, -37, -36, -34, -33, -31, -30, -29, -27,
-26, -24, -23, -22, -20, -19, -17, -16, -15, -13, -12, -10, -9, -8, -6, -5, -3,
-2, 0, 1, 2, 4, 5, 7, 8, 9, 11, 12, 14, 15, 16, 18, 19, 21, 22, 23, 25, 26, 28,
29, 30, 32, 33, 35, 36, 37, 39, 40, 42, 43, 44, 46, 47, 49, 50, 51, 53, 54, 56,
57, 58, 60, 61, 63, 64, 65, 67, 68, 70, 71, 72, 74, 75, 77, 78, 79, 81, 82, 84,
85, 86, 88, 89, 91, 92, 93, 95, 96, 98, 99, 100, 102, 103, 105, 106, 107, 109,
110, 112, 113, 114, 116, 117, 119, 120, 122, 123, 124, 126, 127, 129, 130, 131,
133, 134, 136, 137, 138, 140, 141, 143, 144, 145, 147, 148, 150, 151, 152, 154,
155, 157, 158, 159, 161, 162, 164, 165, 166, 168, 169, 171, 172, 173, 175, 176,
178 };
Table_fv2 = new int[256] { -92, -91, -91, -90, -89, -88, -88, -87, -86, -86,
-85, -84, -83, -83, -82, -81, -81, -80, -79, -78, -78, -77, -76, -76, -75, -74,
-73, -73, -72, -71, -71, -70, -69, -68, -68, -67, -66, -66, -65, -64, -63, -63,
-62, -61, -61, -60, -59, -58, -58, -57, -56, -56, -55, -54, -53, -53, -52, -51,
-51, -50, -49, -48, -48, -47, -46, -46, -45, -44, -43, -43, -42, -41, -41, -40,
-39, -38, -38, -37, -36, -36, -35, -34, -33, -33, -32, -31, -31, -30, -29, -28,
-28, -27, -26, -26, -25, -24, -23, -23, -22, -21, -21, -20, -19, -18, -18, -17,
-16, -16, -15, -14, -13, -13, -12, -11, -11, -10, -9, -8, -8, -7, -6, -6, -5,
-4, -3, -3, -2, -1, 0, 0, 1, 2, 2, 3, 4, 5, 5, 6, 7, 7, 8, 9, 10, 10, 11, 12,
12, 13, 14, 15, 15, 16, 17, 17, 18, 19, 20, 20, 21, 22, 22, 23, 24, 25, 25, 26,
27, 27, 28, 29, 30, 30, 31, 32, 32, 33, 34, 35, 35, 36, 37, 37, 38, 39, 40, 40,
41, 42, 42, 43, 44, 45, 45, 46, 47, 47, 48, 49, 50, 50, 51, 52, 52, 53, 54, 55,
55, 56, 57, 57, 58, 59, 60, 60, 61, 62, 62, 63, 64, 65, 65, 66, 67, 67, 68, 69,
70, 70, 71, 72, 72, 73, 74, 75, 75, 76, 77, 77, 78, 79, 80, 80, 81, 82, 82, 83,
84, 85, 85, 86, 87, 87, 88, 89, 90, 90
};
Table_fu1 = new int[256] { -44, -44, -44, -43, -43, -43, -42, -42, -42, -41,
-41, -41, -40, -40, -40, -39, -39, -39, -38, -38, -38, -37, -37, -37, -36, -36,
-36, -35, -35, -35, -34, -34, -33, -33, -33, -32, -32, -32, -31, -31, -31, -30,
-30, -30, -29, -29, -29, -28, -28, -28, -27, -27, -27, -26, -26, -26, -25, -25,
-25, -24, -24, -24, -23, -23, -22, -22, -22, -21, -21, -21, -20, -20, -20, -19,
-19, -19, -18, -18, -18, -17, -17, -17, -16, -16, -16, -15, -15, -15, -14, -14,
-14, -13, -13, -13, -12, -12, -11, -11, -11, -10, -10, -10, -9, -9, -9, -8, -8,
-8, -7, -7, -7, -6, -6, -6, -5, -5, -5, -4, -4, -4, -3, -3, -3, -2, -2, -2, -1,
-1, 0, 0, 0, 1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 4, 5, 5, 5, 6, 6, 6, 7, 7, 7, 8,
8, 8, 9, 9, 9, 10, 10, 11, 11, 11, 12, 12, 12, 13, 13, 13, 14, 14, 14, 15, 15,
15, 16, 16, 16, 17, 17, 17, 18, 18, 18, 19, 19, 19, 20, 20, 20, 21, 21, 22, 22,
22, 23, 23, 23, 24, 24, 24, 25, 25, 25, 26, 26, 26, 27, 27, 27, 28, 28, 28, 29,
29, 29, 30, 30, 30, 31, 31, 31, 32, 32, 33, 33, 33, 34, 34, 34, 35, 35, 35, 36,
36, 36, 37, 37, 37, 38, 38, 38, 39, 39, 39, 40, 40, 40, 41, 41, 41, 42, 42, 42,
43, 43 };
Table_fu2 = new int[256] { -227, -226, -224, -222, -220, -219, -217, -215, -213,
-212, -210, -208, -206, -204, -203, -201, -199, -197, -196, -194, -192, -190,
-188, -187, -185, -183, -181, -180, -178, -176, -174, -173, -171, -169, -167,
-165, -164, -162, -160, -158, -157, -155, -153, -151, -149, -148, -146, -144,
-142, -141, -139, -137, -135, -134, -132, -130, -128, -126, -125, -123, -121,
-119, -118, -116, -114, -112, -110, -109, -107, -105, -103, -102, -100, -98,
-96, -94, -93, -91, -89, -87, -86, -84, -82, -80, -79, -77, -75, -73, -71, -70,
-68, -66, -64, -63, -61, -59, -57, -55, -54, -52, -50, -48, -47, -45, -43, -41,
-40, -38, -36, -34, -32, -31, -29, -27, -25, -24, -22, -20, -18, -16, -15, -13,
-11, -9, -8, -6, -4, -2, 0, 1, 3, 5, 7, 8, 10, 12, 14, 15, 17, 19, 21, 23, 24,
26, 28, 30, 31, 33, 35, 37, 39, 40, 42, 44, 46, 47, 49, 51, 53, 54, 56, 58, 60,
62, 63, 65, 67, 69, 70, 72, 74, 76, 78, 79, 81, 83, 85, 86, 88, 90, 92, 93, 95,
97, 99, 101, 102, 104, 106, 108, 109, 111, 113, 115, 117, 118, 120, 122, 124,
125, 127, 129, 131, 133, 134, 136, 138, 140, 141, 143, 145, 147, 148, 150, 152,
154, 156, 157, 159, 161, 163, 164, 166, 168, 170, 172, 173, 175, 177, 179, 180,
182, 184, 186, 187, 189, 191, 193, 195, 196, 198, 200, 202, 203, 205, 207, 209,
211, 212, 214, 216, 218, 219, 221, 223, 225
};
width =
iWidth;
height =
iHeight;
length = iWidth *
iHeight;
v
= length;
u = (length * 5) >>
2;
hfWidth
= iWidth >> 1;
}
public bool Convert(byte[] yv12,
ref byte[] rgb24)
{
if
(yv12.Length == 0 || rgb24.Length ==
0)
return
false;
m =
-width;
n
=
-hfWidth;
for (int y = 0; y < height;
y++)
{
m +=
width;
for (int x = 0; x < width;
x++)
{
i = m +
x;
j = n + (x >>
1);
py =
(int)yv12[i];
rdif = Table_fv1[(int)yv12[v +
j]];
invgdif = Table_fu1[(int)yv12[u + j]] + Table_fv2[(int)yv12[v +
j]];
bdif = Table_fu2[(int)yv12[u + j]];
rgb[2] = py +
rdif;
rgb[1] = py -
invgdif;
rgb[0] = py + bdif;
j = m +
x;
i = (j << 1) + j;
for (j = 0; j < 3;
j++)
{
rgb24[i + j] = (byte)((rgb[j] < 0) ? 0 : ((rgb[j] > 255) ? 255 :
rgb[j]));
}
if (x % 4 ==
3)
{
pos = (m + x - 1) *
3;
pos1 = (m + x) *
3;
temp =
rgb24[pos];
rgb24[pos] =
rgb24[pos1];
rgb24[pos1] = temp;
temp = rgb24[pos +
1];
rgb24[pos + 1] = rgb24[pos1 +
1];
rgb24[pos1 + 1] = temp;
temp = rgb24[pos +
2];
rgb24[pos + 2] = rgb24[pos1 +
2];
rgb24[pos1 + 2] =
temp;
}
}
}
return
true;
}
public bool ConvertToInt(IntPtr
yv12, ref int[] rgb24)
{
if
(rgb24.Length ==
0)
return
false;
m =
-width;
n
=
-hfWidth;
int temp1 = 0, temp2=
0;
int
index = 0;
unsafe
{
byte* src =
(byte*)yv12;
for (int y = 0; y < height;
y++)
{
m +=
width;
if
(addHalf)
{
n +=
hfWidth;
addHalf =
false;
}
else
{
addHalf =
true;
}
for (int x = 0; x < width;
x++)
{
i = m +
x;
j = n + (x >> 1);
py = *(src +
i);
temp1 = (int) *(src + v +
j);
temp2 = (int)*(src + u +
j);
rdif =
Table_fv1[temp1];
invgdif = Table_fu1[temp2] +
Table_fv2[temp1];
bdif = Table_fu2[temp2];
rgb[2] = py + rdif;
//R
rgb[1] = py - invgdif;
//G
rgb[0] = py + bdif; //B
for (int colorIndex = 0; colorIndex < 3;
colorIndex++)
{
if (rgb[colorIndex] <
0)
rgb[colorIndex] =
0;
if (rgb[colorIndex] >
255)
rgb[colorIndex] =
255;
}
rgb24[index++] = (int)(rgb[0]<<16 | rgb[1]<<8 | rgb[2]);
j =
i;
i = (j << 1) +
j;
}
}
}
return
true;
}
///
<summary>
/// 将转换后的 RGB
图像数据按照 BMP 格式写入文件。
///
</summary>
/// <param
name="rgbFrame">RGB
格式图像数据。</param>
///
<param
name="width">图像宽（单位：像素）。</param>
/// <param
name="height">图像高（单位：像素）。</param>
/// <param name="bmpFile"> BMP
文件名。</param>
internal static
void WriteBMP(byte[] rgbFrame, int width, int height, string
bmpFile)
{
// 写 BMP
图像文件。
int
yu = width * 3 %
4;
int
bytePerLine =
0;
yu = yu
!= 0 ? 4 - yu :
yu;
bytePerLine = width * 3 + yu;
using
(FileStream fs = File.Open(bmpFile,
FileMode.Create))
{
using (BinaryWriter bw = new
BinaryWriter(fs))
{
bw.Write(‘B‘);
bw.Write(‘M‘);
bw.Write(bytePerLine * height +
54);
bw.Write(0);
bw.Write(54);
bw.Write(40);
bw.Write(width);
bw.Write(height);
bw.Write((ushort)1);
bw.Write((ushort)24);
bw.Write(0);
bw.Write(bytePerLine *
height);
bw.Write(0);
bw.Write(0);
bw.Write(0);
bw.Write(0);
byte[] data = new byte[bytePerLine *
height];
int gIndex = width *
height;
int bIndex = gIndex * 2;
for (int y = height - 1, j = 0; y >= 0; y--,
j++)
{
for (int x = 0, i = 0; x < width;
x++)
{
data[y * bytePerLine + i++] = rgbFrame[bIndex + j * width +
x]; //
B
data[y * bytePerLine + i++] = rgbFrame[gIndex + j * width +
x]; //
G
data[y * bytePerLine + i++] = rgbFrame[j * width + x]; //
R
}
}
bw.Write(data, 0,
data.Length);
bw.Flush();
}
}
}
///
<summary>
/// 将一桢 YUV
格式的图像转换为一桢 RGB 格式图像并转换成BMP图片。
///
</summary>
/// <param
name="yuvFrame">YUV
格式图像数据。</param>
///
<param name="rgbFrame">RGB
格式图像数据。</param>
///
<param
name="width">图像宽（单位：像素）。</param>
/// <param
name="height">图像高（单位：像素）。</param>
///
<returns>Bitmap图片</returns>
internal Bitmap ConvertYUV2RGB(byte[] yuvFrame, byte[] rgbFrame, int width, int
height)
{
int
uIndex = width *
height;
int vIndex = uIndex + ((width * height) >>
2);
int
gIndex = width *
height;
int bIndex = gIndex * 2;
int temp = 0;
//图片为pic1,RGB颜色的二进制数据转换得的int
r,g,b;
Bitmap bm = new Bitmap(width, height);
int r =
0;
int g =
0;
int b =
0;
for
(int y = 0; y < height;
y++)
{
for (int x = 0; x < width;
x++)
{
//
R分量
temp = (int)(yuvFrame[y * width + x] + (yuvFrame[vIndex + (y / 2) * (width / 2)
+ x / 2] - 128) * YUV2RGB_CONVERT_MATRIX[0,
2]);
rgbFrame[y * width + x] = (byte)(temp < 0 ? 0 : (temp > 255 ? 255 :
temp));
//
G分量
temp = (int)(yuvFrame[y * width + x] + (yuvFrame[uIndex + (y / 2) * (width / 2)
+ x / 2] - 128) * YUV2RGB_CONVERT_MATRIX[1, 1] + (yuvFrame[vIndex + (y / 2) *
(width / 2) + x / 2] - 128) * YUV2RGB_CONVERT_MATRIX[1,
2]);
rgbFrame[gIndex + y * width + x] = (byte)(temp < 0 ? 0 : (temp > 255 ? 255
:
temp));
//
B分量
temp = (int)(yuvFrame[y * width + x] + (yuvFrame[uIndex + (y / 2) * (width / 2)
+ x / 2] - 128) * YUV2RGB_CONVERT_MATRIX[2,
1]);
rgbFrame[bIndex + y * width + x] = (byte)(temp < 0 ? 0 : (temp > 255 ? 255
:
temp));
Color c = Color.FromArgb(rgbFrame[y * width + x], rgbFrame[gIndex + y * width +
x], rgbFrame[bIndex + y * width +
x]);
bm.SetPixel(x, y,
c);
}
}
return
bm;
}
}
}
海康威视监控设备的Yv12视频在XNA框架中播放,布布扣,bubuko.com
原文：http://www.cnblogs.com/WolfQsh/p/3642700.html