C#广域网视频的压缩和传输

Question

C#广域网视频的压缩和传输
用C#开发了一个类似QQ的广域网聊天软件，就差视频了。
视频压缩用的是VFW技术，有缓冲区，
网络传输用的是UDP协议（可以穿透NAT）。
现在视频有些花，就像马赛克一样，色块经常丢失。问题可能出现在哪些地方？

Answer 1

udp丢点东西很正常
你在局域网测试应该不会吧?
首先udp不保证数据是不是一定发到了接收方

Answer 2

.net 关于这样深入的资料太少了，楼住是从哪里学的 “频的压缩和传输”技术？

Answer 3

楼主，我现在只能捕捉到摄像头视频，可不知到该如何压缩传输，楼主能发一份压缩传输部分的代码吗
[email protected] 
谢了先

Answer 4

to: lgwwwusing System;
using System.Runtime.InteropServices;namespace VideoPreview.Utilities
{
    public class CCodec
    {
        private int hic;
        //private IntPtr hic;
        private COMPVARS cp;
        private BITMAPINFO cbiIn;
        private BITMAPINFO cbiOut;        private int dehic;
        //private IntPtr dehic;
        private COMPVARS decp;
        private BITMAPINFO decbiIn;
        private BITMAPINFO decbiOut;        public bool InitCompress(BITMAPINFOHEADER bi)
        {
            this.cp = new COMPVARS();
            cp.cbSize = Marshal.SizeOf(this.cp);
            cp.dwFlags = 1; // ICMF_COMPVAES_VALID
            cp.fccHandler = 2021026148;
            cp.fccType = FOURCC.ICTYPE_VIDEO;            cp.lKey = 15;
            cp.lQ = 10000;            this.hic = ICOpen(cp.fccType, cp.fccHandler, ICMODE.ICMODE_COMPRESS | ICMODE.ICMODE_DECOMPRESS);
            if (this.hic != 0)
            {
                cp.hic = this.hic;
                cbiIn = new BITMAPINFO();
                cbiIn.bmiHeader = bi;
                if (ICSendMessage(this.hic, ICM_COMPRESS_GET_FORMAT, ref this.cbiIn, ref this.cbiOut) == ICERR_OK)
                {
                    return ICSeqCompressFrameStart(ref this.cp, ref this.cbiIn);
                }
                else
                {
                    return false;
                }
            }
            else
            {
                return false;
            }
        }        public byte[] CPProcess(byte[] data)
        {
            if (this.hic == 0)
            {
                return null;
            }
            bool key = false;
            int size = 0;
            try
            {
                lock (data)
                {
                    IntPtr source = ICSeqCompressFrame(
                        ref this.cp,
                        0,
                        data,
                        ref key,
                        ref size);
                    if (size > 0)
                    {
                        byte[] cpdata = new byte[size];
                        try
                        {
                            Marshal.Copy(source, cpdata, 0, size);
                        }
                        catch
                        {
                            //System.Windows.Forms.MessageBox.Show("Data array over flow!", "CompressframeError", System.Windows.Forms.MessageBoxButtons.OK, System.Windows.Forms.MessageBoxIcon.Information);
                        }
                        return cpdata;
                    }
                    else
                    {
                        return null;
                    }
                }
            }
            catch (System.Exception ex)
            {
                //System.Windows.Forms.MessageBox.Show("Compress Exception : " + ex.Message);
            }
            return null;
        }        public bool InitDecompress()
        {
            if (this.cp.hic != 0)
            {
                this.decp = this.cp;
                this.dehic = this.hic; // this.cp.hic;
            }
            else
            {
                return false;
            }            //this.dehic = ICOpen(cp.fccType, cp.fccHandler, ICMODE.ICMODE_DECOMPRESS);            this.decbiIn = this.cbiOut;
            this.decbiOut = this.cbiIn;            if (this.dehic != 0)
            {
                if (ICSendMessage(this.dehic, ICM_DECOMPRESS_BEGIN, ref this.decbiIn, ref this.decbiOut) == ICERR_OK)
                {
                    return true;
                }
                else
                {
                    return false;
                }
            }
            else
            {
                return false;
            }
        }        public byte[] DECCPProcess(byte[] data)
        {
            if (this.dehic == 0)
            {
                return null;
            }
            byte[] deccpdata = new byte[this.decbiOut.bmiHeader.biSizeImage];
            try
            {
                if (ICDecompress(this.dehic, 0, ref this.decbiIn.bmiHeader, data, ref this.decbiOut.bmiHeader, deccpdata) != ICERR_OK)
                {
                    return null;
                }
            }
            catch (Exception ex)
            {
                //System.Windows.Forms.MessageBox.Show("Decompress Exception : " + ex.Message);
            }
            return deccpdata;
        }        public void CCodecClose()
        {
            try
            {
                if (this.hic != 0)
                {
                    try
                    {
                        ICSeqCompressFrameEnd(ref this.cp);
                    }
                    catch { }
                    ICClose(this.hic);
                }
                if (this.dehic != 0)
                {
                    try
                    {
                        ICSendMessage(hic, ICM_USER + 14, 0, 0);
                    }
                    catch { }
                    ICClose(this.dehic);
                }
            }
            catch { }
        }

Answer 5

        #region
        [DllImport("MSVFW32.dll")]
        public static extern int ICCompressGetFormat(
            //int hic,
            IntPtr hic,
            ref BITMAPINFO lpbiInput,
            ref BITMAPINFO lpbiOutput
            );        [DllImport("MSVFW32.dll")]
        public static extern int ICDecompressBegin(
            //int hic,
            IntPtr hic,
            ref BITMAPINFO lpbiInput,
            ref BITMAPINFO lpbiOutput
            );        [DllImport("VFW32.dll")]
        public static extern int ICDecompressGetFormat(
            //int hic,
            IntPtr hic,
            ref BITMAPINFO lpbiInput,
            ref BITMAPINFO lpbiOutput
            );        [DllImport("MSVFW32.dll")]
        public static extern void ICSeqCompressFrameEnd(ref COMPVARS pc);        [DllImport("MSVFW32.dll")]
        public static extern int ICCompressGetFormatSize(
            int hic,
            ref BITMAPINFO lpbiInput
            );        [DllImport("MSVFW32.dll")]
        public static extern bool ICSeqCompressFrameStart(
            ref COMPVARS pc,
            //ref BITMAPINFO lpbiIn
            ref BITMAPINFO lpbiIn
            );        [DllImport("MSVFW32.dll")]
        public static extern IntPtr ICSeqCompressFrame(
            ref COMPVARS pc,
            uint uiFlags,
            byte[] lpBits,
            ref bool pfKey,
            //ref ushort pfKey,
            //ref long plSize
            ref int plSize
            );        [DllImport("MSVFW32.dll", CharSet = CharSet.Ansi)]
        public static extern int ICGetInfo(
            int hic,
            ICINFO lpicinfo,
            int cb
            );        [DllImport("MSVFW32.dll")]
        public static extern bool ICCompressorChoose(
            IntPtr hwnd,
            int uiFlags,
            //int pvIn,
            //int lpData,
            IntPtr pvIn,
            IntPtr lpData,
            ref COMPVARS pc,
            string lpszTitle
            );        [DllImport("MSVFW32.dll")]
        public static extern int ICLocate(
            int fccType,
            int fccHandler,
            ref BITMAPINFOHEADER lpbiIn,
            ref BITMAPINFOHEADER lpbiOut,
            short wFlags
            );        [DllImport("MSVFW32.dll"), PreserveSig]
        public static extern int ICOpen(uint fccType, uint fccHandler, ICMODE wMode);
        //public static extern IntPtr ICOpen(uint fccType, uint fccHandler, uint wmode); // ICMODE wMode);        [DllImport("MSVFW32.dll"), PreserveSig]
        public static extern int ICDecompressOpen(
            int fccType,
            int fccHandler,
            ref BITMAPINFOHEADER lpbiIn,
            ref BITMAPINFOHEADER lpbiOut
            );        [DllImport("MSVFW32.dll")]
        public static extern int ICClose(int hic);        [DllImport("MSVFW32.dll")]
        public static extern int ICCompress(
            int hic,
            int dwFlags,        // flags
            ref BITMAPINFOHEADER lpbiOutput,     // output format
            IntPtr lpData,         // output data
            ref BITMAPINFOHEADER lpbiInput,      // format of frame to compress
            IntPtr lpBits,         // frame data to compress
            int lpckid,         // ckid for data in AVI file
            int lpdwFlags,      // flags in the AVI index.
            int lFrameNum,      // frame number of seq.
            int dwFrameSize,    // reqested size in bytes. (if non zero)
            int dwQuality,      // quality within one frame
            int lpbiPrev,       // format of previous frame
            int lpPrev          // previous frame
            );        [DllImport("MSVFW32.dll")]
        public static extern int ICDecompress(
            int hic,
            //IntPtr hic,
            //int dwFlags,
            uint dwFlags,
            ref BITMAPINFOHEADER lpbiFormat,
            byte[] lpData,
            ref BITMAPINFOHEADER lpbi,
            byte[] lpBits
            );        [DllImport("MSVFW32.dll")]
        public static extern int ICSendMessage(int hic, int msg, ref BITMAPINFO dw1, ref BITMAPINFO dw2);        [DllImport("MSVFW32.dll")]
        public static extern int ICSendMessage(int hic, int msg, int dw1, int dw2);        [DllImport("MSVFW32.dll")]
        public static extern int ICSendMessage(int hic, int msg, ICINFO dw1, int dw2);
        public static readonly int DRV_USER = 0x4000;
        public static readonly int ICM_USER = (DRV_USER + 0x0000);
        public static readonly int ICM_COMPRESS_BEGIN = (ICM_USER + 7);    // begin a series of compress calls.
        public static readonly int ICM_COMPRESS = (ICM_USER + 8);   // compress a frame
        public static readonly int ICM_COMPRESS_END = (ICM_USER + 9);   // end of a series of compress calls.
        public static readonly int ICM_COMPRESS_GET_FORMAT = (ICM_USER + 4);
        public static readonly int ICM_DECOMPRESS_BEGIN = (ICM_USER + 12);   // start a series of decompress calls
        public static readonly int ICM_DECOMPRESS = (ICM_USER + 13);   // decompress a frame
        public static readonly int ICM_DECOMPRESS_END = (ICM_USER + 14);        public static readonly int ICERR_OK = 0x0;
        #endregion
    }
}其实也没什么，用的是Divx编码器。

Answer 6

to : purple_tide
  这个我当然知道。我在接受端设置了缓冲和帧重排序，仔细看了看好像还是传输的问题。
今天改了一个参数效果比以前好多了，但摄像头捕获禁止的物体时仍然会有花屏现象。

Answer 7

也没什么，都是调用的Windows的API.

Answer 8

看下cp.fccType, cp.fccHandler是否对应，或者系统中是否有你需要的编码器。上面的代码中用的是Divx编码器

Answer 9

楼主的这份代码在网上挺多的，我也看了这份代码，我觉得这个代码不行，上面用的DivX编码器，如果客户端没有安装Divx编码器，根本就实现不了压缩，所以必须解决聊天客户端检测目标机器是否安装了相应解码器，如果没有安装，自己得实现安装。
再一个问题，我做了试验，即使安装了Divx解码器，压缩得到的数据有的也挺大的，自己还必须实现分包，包太大的话是不适合在广域网上传输的(视频传输一般用Udp传，大包在网络状况不好的情况下是会丢失的)。

Answer 10

我觉得这个不是问题，做一个安装包就可以了，如果不借助第三方压缩方式，你自己写就复杂多了。所以你应该学会利用资源，做个安装包，先安装divx播放代码就可以了。

Answer 11

确实，那个hic为0的就是没有编码包

Answer 12

同样问题,hic为零,数据得不到,

Answer 13

同样问题,hic为零,数据得不到,

Answer 14

确实是解码的原因 下载一个叫mpeg4x解码器安装即可

Answer 15

ffdshow MPEG-4 Video Decoder
需要下载这个解码器才能工作。
http://www.onlinedown.net/soft/5636.htm

Answer 16

ffdshow MPEG-4 Video Decoder
需要下载这个解码器才能工作。
http://www.onlinedown.net/soft/5636.htm