diff --git a/README.md b/README.md
index 3834581..874f202 100644
--- a/README.md
+++ b/README.md
@@ -8,6 +8,7 @@
 3.1  [将1078的数据(h264)编码成FLV](#1078flv)  
 3.2  [将1078的数据(h264)编码成HLS](#1078hls)  
 3.3  [将1078的数据(h264)编码成FMp4](#1078fmp4)  
+4. ***====音频部分暂未实现====***
 
 [![MIT Licence](https://img.shields.io/github/license/mashape/apistatus.svg)](https://github.com/SmallChi/JT1078/blob/master/LICENSE)[![Github Build status](https://github.com/SmallChi/JT1078/workflows/.NET%20Core/badge.svg)]()
 
@@ -18,6 +19,7 @@
 | Install-Package JT1078 | ![JT1078](https://img.shields.io/nuget/v/JT1078.svg) | ![JT1078](https://img.shields.io/nuget/dt/JT1078.svg) |
 | Install-Package JT1078.Flv | ![JT1078.Flv](https://img.shields.io/nuget/v/JT1078.Flv.svg) | ![JT1078.Flv](https://img.shields.io/nuget/dt/JT1078.Flv.svg) |
 | Install-Package JT1078.Hls | ![JT1078.Hls](https://img.shields.io/nuget/v/JT1078.Hls.svg) | ![JT1078.Hls](https://img.shields.io/nuget/dt/JT1078.Hls.svg) |
+| Install-Package JT1078.FMp4 | ![JT1078.FMp4](https://img.shields.io/nuget/v/JT1078.FMp4.svg) | ![JT1078.FMp4](https://img.shields.io/nuget/dt/JT1078.FMp4.svg) |
 | Install-Package JT808.Protocol.Extensions.JT1078 | ![JT808.Protocol.Extensions.JT1078](https://img.shields.io/nuget/v/JT808.Protocol.Extensions.JT1078.svg) | ![JT808](https://img.shields.io/nuget/dt/JT808.Protocol.Extensions.JT1078.svg) |
 | Install-Package JT809.Protocol.Extensions.JT1078 | ![JT809.Protocol.Extensions.JT1078](https://img.shields.io/nuget/v/JT809.Protocol.Extensions.JT1078.svg) | ![JT809](https://img.shields.io/nuget/dt/JT809.Protocol.Extensions.JT1078.svg) |
 
@@ -180,7 +182,13 @@ Platform=AnyCpu  Server=False  Toolchain=.NET Core 3.1
 3. 掌握TS编码；
 4. 掌握Hls编码；
 
-> 音频暂未实现
+## <span id="1078fmp4">基于JT1078的FMp4视频编码器</span>
+
+### 前提条件
+
+1. 掌握JT078解码；
+2. 了解H264解码；
+3. 掌握FMp4编码；
 
 ### 使用BenchmarkDotNet性能测试报告（只是玩玩，不能当真）
 
diff --git a/src/JT1078.FMp4/Boxs/ChunkOffsetBox.cs b/src/JT1078.FMp4/Boxs/ChunkOffsetBox.cs
index f8c0b97..cddea67 100644
--- a/src/JT1078.FMp4/Boxs/ChunkOffsetBox.cs
+++ b/src/JT1078.FMp4/Boxs/ChunkOffsetBox.cs
@@ -6,8 +6,16 @@ using System.Text;
 
 namespace JT1078.FMp4
 {
+    /// <summary>
+    /// stco
+    /// </summary>
     public class ChunkOffsetBox : FullBox, IFMp4MessagePackFormatter
     {
+        /// <summary>
+        /// stco
+        /// </summary>
+        /// <param name="version"></param>
+        /// <param name="flags"></param>
         public ChunkOffsetBox( byte version=0, uint flags=0) : base("stco", version, flags)
         {
         }
@@ -20,7 +28,21 @@ namespace JT1078.FMp4
 
         public void ToBuffer(ref FMp4MessagePackWriter writer)
         {
-            throw new NotImplementedException();
+            Start(ref writer);
+            WriterFullBoxToBuffer(ref writer);
+            if(ChunkOffset!=null && ChunkOffset.Count > 0)
+            {
+                writer.WriteUInt32((uint)ChunkOffset.Count);
+                foreach(var item in ChunkOffset)
+                {
+                    writer.WriteUInt32(item);
+                }
+            }
+            else
+            {
+                writer.WriteUInt32(0);
+            }
+            End(ref writer);
         }
     }
 }
diff --git a/src/JT1078.FMp4/Boxs/CompositionOffsetBox.cs b/src/JT1078.FMp4/Boxs/CompositionOffsetBox.cs
index 57700a6..1b49433 100644
--- a/src/JT1078.FMp4/Boxs/CompositionOffsetBox.cs
+++ b/src/JT1078.FMp4/Boxs/CompositionOffsetBox.cs
@@ -6,8 +6,16 @@ using System.Text;
 
 namespace JT1078.FMp4
 {
+    /// <summary>
+    /// ctts
+    /// </summary>
     public class CompositionOffsetBox : FullBox, IFMp4MessagePackFormatter
     {
+        /// <summary>
+        /// ctts
+        /// </summary>
+        /// <param name="version"></param>
+        /// <param name="flags"></param>
         public CompositionOffsetBox(byte version=0, uint flags=0) : base("ctts", version, flags)
         {
         }
@@ -17,7 +25,30 @@ namespace JT1078.FMp4
 
         public void ToBuffer(ref FMp4MessagePackWriter writer)
         {
-            throw new NotImplementedException();
+            Start(ref writer);
+            WriterFullBoxToBuffer(ref writer);
+            if(CompositionOffsetInfos!=null && CompositionOffsetInfos.Count > 0)
+            {
+                writer.WriteUInt32((uint)CompositionOffsetInfos.Count);
+                foreach(var item in CompositionOffsetInfos)
+                {
+                    if (Version == 0)
+                    {
+                        writer.WriteUInt32(item.SampleCount);
+                        writer.WriteUInt32(item.SampleOffset);
+                    }
+                    else
+                    {
+                        writer.WriteUInt32(item.SampleCount);
+                        writer.WriteInt32(item.SignedSampleOffset);
+                    }
+                }
+            }
+            else
+            {
+                writer.WriteUInt32(0);
+            }
+            End(ref writer);
         }
 
         public class CompositionOffsetInfo
diff --git a/src/JT1078.FMp4/Boxs/MediaBox.cs b/src/JT1078.FMp4/Boxs/MediaBox.cs
index eff4e13..cf456c0 100644
--- a/src/JT1078.FMp4/Boxs/MediaBox.cs
+++ b/src/JT1078.FMp4/Boxs/MediaBox.cs
@@ -1,4 +1,6 @@
-using System;
+using JT1078.FMp4.Interfaces;
+using JT1078.FMp4.MessagePack;
+using System;
 using System.Collections.Generic;
 using System.Text;
 
@@ -7,7 +9,7 @@ namespace JT1078.FMp4
     /// <summary>
     /// mdia
     /// </summary>
-    public class MediaBox : Mp4Box
+    public class MediaBox : Mp4Box, IFMp4MessagePackFormatter
     {
         /// <summary>
         /// mdia
@@ -27,5 +29,14 @@ namespace JT1078.FMp4
         /// minf
         /// </summary>
         public MediaInformationBox MediaInformationBox { get; set; }
+
+        public void ToBuffer(ref FMp4MessagePackWriter writer)
+        {
+            Start(ref writer);
+            MediaHeaderBox.ToBuffer(ref writer);
+            HandlerBox.ToBuffer(ref writer);
+            MediaInformationBox.ToBuffer(ref writer);
+            End(ref writer);
+        }
     }
 }
diff --git a/src/JT1078.FMp4/Boxs/MovieBox.cs b/src/JT1078.FMp4/Boxs/MovieBox.cs
index eace22e..d8530d2 100644
--- a/src/JT1078.FMp4/Boxs/MovieBox.cs
+++ b/src/JT1078.FMp4/Boxs/MovieBox.cs
@@ -27,7 +27,7 @@ namespace JT1078.FMp4
         /// </summary>
         public TrackBox TrackBox { get; set; }
         /// <summary>
-        /// trak
+        /// mvex
         /// </summary>
         public MovieExtendsBox MovieExtendsBox { get; set; }
 
@@ -35,7 +35,8 @@ namespace JT1078.FMp4
         {
             Start(ref writer);
             MovieHeaderBox.ToBuffer(ref writer);
-     
+            TrackBox.ToBuffer(ref writer);
+            MovieExtendsBox.ToBuffer(ref writer);
             End(ref writer);
         }
     }
diff --git a/src/JT1078.FMp4/Boxs/MovieExtendsBox.cs b/src/JT1078.FMp4/Boxs/MovieExtendsBox.cs
index d7f966d..ceeb636 100644
--- a/src/JT1078.FMp4/Boxs/MovieExtendsBox.cs
+++ b/src/JT1078.FMp4/Boxs/MovieExtendsBox.cs
@@ -1,4 +1,6 @@
-using System;
+using JT1078.FMp4.Interfaces;
+using JT1078.FMp4.MessagePack;
+using System;
 using System.Collections.Generic;
 using System.Text;
 
@@ -7,7 +9,7 @@ namespace JT1078.FMp4
     /// <summary>
     /// mvex
     /// </summary>
-    public class MovieExtendsBox : Mp4Box
+    public class MovieExtendsBox : Mp4Box, IFMp4MessagePackFormatter
     {
         /// <summary>
         /// mvex
@@ -17,5 +19,22 @@ namespace JT1078.FMp4
         }
         public MovieExtendsHeaderBox MovieExtendsHeaderBox { get; set; }
         public List<TrackExtendsBox> TrackExtendsBoxs { get; set; }
+
+        public void ToBuffer(ref FMp4MessagePackWriter writer)
+        {
+            Start(ref writer);
+            if (MovieExtendsHeaderBox != null)
+            {
+                MovieExtendsHeaderBox.ToBuffer(ref writer);
+            }
+            if (TrackExtendsBoxs != null)
+            {
+                foreach(var item in TrackExtendsBoxs)
+                {
+                    item.ToBuffer(ref writer);
+                }
+            }
+            End(ref writer);
+        }
     }
 }
diff --git a/src/JT1078.FMp4/Boxs/MovieExtendsHeaderBox.cs b/src/JT1078.FMp4/Boxs/MovieExtendsHeaderBox.cs
index b9dcc79..4c4ea6e 100644
--- a/src/JT1078.FMp4/Boxs/MovieExtendsHeaderBox.cs
+++ b/src/JT1078.FMp4/Boxs/MovieExtendsHeaderBox.cs
@@ -1,14 +1,33 @@
-using System;
+using JT1078.FMp4.Interfaces;
+using JT1078.FMp4.MessagePack;
+using System;
 using System.Collections.Generic;
 using System.Text;
 
 namespace JT1078.FMp4
 {
-    public class MovieExtendsHeaderBox : FullBox
+    /// <summary>
+    /// mehd
+    /// </summary>
+    public class MovieExtendsHeaderBox : FullBox, IFMp4MessagePackFormatter
     {
+        /// <summary>
+        /// mehd
+        /// </summary>
+        /// <param name="version"></param>
+        /// <param name="flags"></param>
         public MovieExtendsHeaderBox( byte version, uint flags=0) : base("mehd", version, flags)
         {
         }
+
         public uint FragmentDuration { get; set; }
+
+        public void ToBuffer(ref FMp4MessagePackWriter writer)
+        {
+            Start(ref writer);
+            WriterFullBoxToBuffer(ref writer);
+            writer.WriteUInt32(FragmentDuration);
+            End(ref writer);
+        }
     }
 }
diff --git a/src/JT1078.FMp4/Boxs/SampleDescriptionBox.cs b/src/JT1078.FMp4/Boxs/SampleDescriptionBox.cs
index e320b16..de595aa 100644
--- a/src/JT1078.FMp4/Boxs/SampleDescriptionBox.cs
+++ b/src/JT1078.FMp4/Boxs/SampleDescriptionBox.cs
@@ -32,7 +32,8 @@ namespace JT1078.FMp4
             WriterFullBoxToBuffer(ref writer);
             if(SampleEntries!=null && SampleEntries.Count > 0)
             {
-                foreach(var item in SampleEntries)
+                writer.WriteUInt32((uint)SampleEntries.Count);
+                foreach (var item in SampleEntries)
                 {
                     item.ToBuffer(ref writer);
                 }
diff --git a/src/JT1078.FMp4/Boxs/SampleToChunkBox.cs b/src/JT1078.FMp4/Boxs/SampleToChunkBox.cs
index f93c996..ae4b69b 100644
--- a/src/JT1078.FMp4/Boxs/SampleToChunkBox.cs
+++ b/src/JT1078.FMp4/Boxs/SampleToChunkBox.cs
@@ -6,8 +6,16 @@ using System.Text;
 
 namespace JT1078.FMp4
 {
+    /// <summary>
+    /// stsc
+    /// </summary>
     public class SampleToChunkBox : FullBox, IFMp4MessagePackFormatter
     {
+        /// <summary>
+        /// stsc
+        /// </summary>
+        /// <param name="version"></param>
+        /// <param name="flags"></param>
         public SampleToChunkBox(byte version=0, uint flags=0) : base("stsc", version, flags)
         {
         }
@@ -16,7 +24,23 @@ namespace JT1078.FMp4
 
         public void ToBuffer(ref FMp4MessagePackWriter writer)
         {
-            throw new NotImplementedException();
+            Start(ref writer);
+            WriterFullBoxToBuffer(ref writer);
+            if(SampleToChunkInfos!=null && SampleToChunkInfos.Count > 0)
+            {
+                writer.WriteUInt32((uint)SampleToChunkInfos.Count);
+                foreach(var item in SampleToChunkInfos)
+                {
+                    writer.WriteUInt32(item.FirstChunk);
+                    writer.WriteUInt32(item.SamplesPerChunk);
+                    writer.WriteUInt32(item.SampleDescriptionIindex);
+                }
+            }
+            else
+            {
+                writer.WriteUInt32(0);
+            }
+            End(ref writer);
         }
 
         public class SampleToChunkInfo
diff --git a/src/JT1078.FMp4/Boxs/TimeToSampleBox.cs b/src/JT1078.FMp4/Boxs/TimeToSampleBox.cs
index 82afa45..ea8d545 100644
--- a/src/JT1078.FMp4/Boxs/TimeToSampleBox.cs
+++ b/src/JT1078.FMp4/Boxs/TimeToSampleBox.cs
@@ -6,8 +6,16 @@ using System.Text;
 
 namespace JT1078.FMp4
 {
+    /// <summary>
+    /// stts
+    /// </summary>
     public class TimeToSampleBox : FullBox, IFMp4MessagePackFormatter
     {
+        /// <summary>
+        /// stts
+        /// </summary>
+        /// <param name="version"></param>
+        /// <param name="flags"></param>
         public TimeToSampleBox(byte version = 0, uint flags = 0) : base("stts", version, flags)
         {
         }
@@ -18,7 +26,22 @@ namespace JT1078.FMp4
 
         public void ToBuffer(ref FMp4MessagePackWriter writer)
         {
-            throw new NotImplementedException();
+            Start(ref writer);
+            WriterFullBoxToBuffer(ref writer);
+            if(TimeToSampleInfos!=null && TimeToSampleInfos.Count > 0)
+            {
+                writer.WriteUInt32((uint)TimeToSampleInfos.Count);
+                foreach (var item in TimeToSampleInfos)
+                {
+                    writer.WriteUInt32(item.SampleCount);
+                    writer.WriteUInt32(item.SampleDelta);
+                }
+            }
+            else
+            {
+                writer.WriteUInt32(0);
+            }
+            End(ref writer);
         }
 
         public class TimeToSampleInfo
diff --git a/src/JT1078.FMp4/Boxs/TrackBox.cs b/src/JT1078.FMp4/Boxs/TrackBox.cs
index 4c08eae..6464972 100644
--- a/src/JT1078.FMp4/Boxs/TrackBox.cs
+++ b/src/JT1078.FMp4/Boxs/TrackBox.cs
@@ -1,4 +1,6 @@
-using System;
+using JT1078.FMp4.Interfaces;
+using JT1078.FMp4.MessagePack;
+using System;
 using System.Collections.Generic;
 using System.Text;
 
@@ -7,7 +9,7 @@ namespace JT1078.FMp4
     /// <summary>
     /// trak
     /// </summary>
-    public class TrackBox : Mp4Box
+    public class TrackBox : Mp4Box, IFMp4MessagePackFormatter
     {
         /// <summary>
         /// trak
@@ -25,5 +27,13 @@ namespace JT1078.FMp4
         /// mdia
         /// </summary>
         public MediaBox MediaBox { get; set; }
+
+        public void ToBuffer(ref FMp4MessagePackWriter writer)
+        {
+            Start(ref writer);
+            TrackHeaderBox.ToBuffer(ref writer);
+            MediaBox.ToBuffer(ref writer);
+            End(ref writer);
+        }
     }
 }
diff --git a/src/JT1078.FMp4/Boxs/TrackExtendsBox.cs b/src/JT1078.FMp4/Boxs/TrackExtendsBox.cs
index 2fcbbfe..6fc6017 100644
--- a/src/JT1078.FMp4/Boxs/TrackExtendsBox.cs
+++ b/src/JT1078.FMp4/Boxs/TrackExtendsBox.cs
@@ -1,10 +1,12 @@
-using System;
+using JT1078.FMp4.Interfaces;
+using JT1078.FMp4.MessagePack;
+using System;
 using System.Collections.Generic;
 using System.Text;
 
 namespace JT1078.FMp4
 {
-    public class TrackExtendsBox : FullBox
+    public class TrackExtendsBox : FullBox, IFMp4MessagePackFormatter
     {
         public TrackExtendsBox(byte version=0, uint flags=0) : base("trex", version, flags)
         {
@@ -15,5 +17,17 @@ namespace JT1078.FMp4
         public uint DefaultSampleDuration { get; set; }
         public uint DefaultSampleSize { get; set; }
         public uint DefaultSampleFlags { get; set; }
+
+        public void ToBuffer(ref FMp4MessagePackWriter writer)
+        {
+            Start(ref writer);
+            WriterFullBoxToBuffer(ref writer);
+            writer.WriteUInt32(TrackID);
+            writer.WriteUInt32(DefaultSampleDescriptionIndex);
+            writer.WriteUInt32(DefaultSampleDuration);
+            writer.WriteUInt32(DefaultSampleSize);
+            writer.WriteUInt32(DefaultSampleFlags);
+            End(ref writer);
+        }
     }
 }
diff --git a/src/JT1078.FMp4/JT1078.FMp4.xml b/src/JT1078.FMp4/JT1078.FMp4.xml
index b947e02..bb40784 100644
--- a/src/JT1078.FMp4/JT1078.FMp4.xml
+++ b/src/JT1078.FMp4/JT1078.FMp4.xml
@@ -747,7 +747,7 @@
             </summary>
             <param name="writer"></param>
         </member>
-        <!-- Badly formed XML comment ignored for member "P:JT1078.FMp4.Samples.AudioSampleEntry.Samplerate" -->
+        <!-- Badly formed XML comment ignored for member "P:JT1078.FMp4.Samples.AudioSampleEntry.SampleRate" -->
         <member name="T:JT1078.FMp4.Samples.AVC1SampleEntry">
             <summary>
             avc1
diff --git a/src/JT1078.FMp4/Samples/AudioSampleEntry.cs b/src/JT1078.FMp4/Samples/AudioSampleEntry.cs
index a92abb9..9be46b0 100644
--- a/src/JT1078.FMp4/Samples/AudioSampleEntry.cs
+++ b/src/JT1078.FMp4/Samples/AudioSampleEntry.cs
@@ -1,4 +1,5 @@
-using System;
+using JT1078.FMp4.MessagePack;
+using System;
 using System.Collections.Generic;
 using System.Text;
 
@@ -15,8 +16,22 @@ namespace JT1078.FMp4.Samples
         public ushort PreDefined { get; set; } = 0;
         public ushort Reserved2 { get; set; } = 0;
         /// <summary>
-        /// { default samplerate of media}<<16;
+        /// 
+        ///  default samplerate of media << 16;
         /// </summary>
-        public uint Samplerate{ get; set; }
+        public uint SampleRate{ get; set; }
+
+        protected void WriterAudioSampleEntryToBuffer(ref FMp4MessagePackWriter writer)
+        {
+            foreach(var item in Reserved1)
+            {
+                writer.WriteUInt32(item);
+            }
+            writer.WriteUInt16(ChannelCount);
+            writer.WriteUInt16(SampleSize);
+            writer.WriteUInt16(PreDefined);
+            writer.WriteUInt16(Reserved2);
+            writer.WriteUInt32(SampleRate<<16);
+        }
     }
 }