rtmp

README

gortmp

一个简单的RTMP流媒体服务器包，整体包功能包括点播server端本地视频和摄像头实时推流点播两部分

run a simple rtmp server

package main

import (
    "github.com/gortmp"
)
func main() {
    rtmp.Serve()
}

点播

默认视频路径为"gortmp/video/"，使用vlc播放器或adobe Flash Player网页测试版输入点播url:"rtmp://IP/gortmp/视频名称"，即可开始播放视频，目前仅支持视频h264编码的flv文件

直播

使用第三方程序ffmpeg或etc文件夹中的LIVE视频采集程序采集本地USB摄像头或网络摄像头，选择视频编码方式为h264，音频编码方式AVC，将摄像头信号推送到"rtmp://IP/live/livestream"，客户端通过vlc或Adobe Flash Player网页测试版打开url即可看到直播画面

参考

SPEC

• Adobe官方RTMP协议Adobe's Real Time Messaging Protocol
  此协议属于应用层，被设计用来在合适的传输协议（如TCP）上复用和打包多媒体传输流（如音频、视频和互动内容），里面介绍了基础的定义，握手、连接和传输的方式
• AMF0格式协议Action Message Format -- AMF 0
  AMF是Adobe独家开发出来的通讯协议，它采用二进制压缩，序列化、反序列化、传输数据，从而为Flash 播放器与Flash Remoting网关通信提供了一种轻量级的、高效能的通信方式
• FLV文件协议Adobe Flash Video File Format Specification
  介绍了flv文件的封装格式，flv是一种流媒体常用的网络视频格式，被Adobe Flash Player原生支持

博客

• Adobe 官方公布的 RTMP 规范+未公布的部分
• 从流程上对rtmp协议经行总结
  介绍了RTMP的复杂握手模式，并通过抓包的方法对官方协议中没有介绍的消息命令进行解释
• 使用RTMP协议进行视频直播
  用实例分析了对一个flv文件解析并传输的过程
• 最简单的基于Flash的流媒体示例：网页播放器（HTTP，RTMP，HLS）

Documentation

Index

• Constants
• func Serve()

Constants

const (
	AMF_NUMBER  = 0x00
	AMF_BOOLEAN = 0x01
	AMF_STRING  = 0x02
	AMF_OBJECT  = 0x03
	AMF_NULL    = 0x05
	AMF_MAP     = 0x08
	AMF_OBJEND  = 0x09
	AMF_ARRAY   = 0x0a
)

AMF Object objType

const (
	HEADER_FMT_FULL                   = 0x00
	HEADER_FMT_SAME_STREAM            = 0x01
	HEADER_FMT_SAME_LENGTH_AND_STREAM = 0x02
	HEADER_FMT_CONTINUATION           = 0x03
)

Chunk Message Header - "fmt" field values

const (
	CS_ID_PROTOCOL_CONTROL = uint32(2) //Message Type ID must be 0
	CS_ID_COMMAND          = uint32(3)
	CS_ID_USER_CONTROL     = uint32(4)
)

Chunk stream ID

const (

	// The value of the chunk size is carried as 4-byte message payload. A
	// default value exists for chunk size, but if the sender wants to
	// change this value it notifies the peer about it through this
	// protocol message. For example, a client wants to send 131 bytes of
	// data and the chunk size is at its default value of 128. So every
	// message from the client gets split into two chunks. The client can
	// choose to change the chunk size to 131 so that every message get
	// split into two chunks. The client MUST send this protocol message to
	// the server to notify that the chunk size is set to 131 bytes.
	// The maximum chunk size can be 65536 bytes. Chunk size is maintained
	// independently for server to client communication and client to server
	// communication.
	//
	//  0                   1                   2                   3
	//  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	// |                          chunk size (4 bytes)                 |
	// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	// Figure 2 Pay load for the protocol message ‘Set Chunk Size’
	//
	// chunk size: 32 bits
	//   This field holds the new chunk size, which will be used for all
	//   future chunks sent by this chunk stream.
	SET_CHUNK_SIZE = uint8(1)

	// Abort Message
	//
	// Protocol control message 2, Abort Message, is used to notify the peer
	// if it is waiting for chunks to complete a message, then to discard
	// the partially received message over a chunk stream and abort
	// processing of that message. The peer receives the chunk stream ID of
	// the message to be discarded as payload of this protocol message. This
	// message is sent when the sender has sent part of a message, but wants
	// to tell the receiver that the rest of the message will not be sent.
	//
	//  0                   1                   2                   3
	//  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	// |                        chunk stream id (4 bytes)              |
	// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	// Figure 3 Pay load for the protocol message ‘Abort Message’.
	//
	//
	// chunk stream ID: 32 bits
	//   This field holds the chunk stream ID, whose message is to be
	//   discarded.
	ABORT_MESSAGE = uint8(2)

	// Acknowledgement
	//
	// The client or the server sends the acknowledgment to the peer after
	// receiving bytes equal to the window size. The window size is the
	// maximum number of bytes that the sender sends without receiving
	// acknowledgment from the receiver. The server sends the window size to
	// the client after application connects. This message specifies the
	// sequence number, which is the number of the bytes received so far.
	//  0                   1                   2                   3
	//  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	// |                        sequence number (4 bytes)              |
	// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	// Figure 4 Pay load for the protocol message ‘Acknowledgement’.
	//
	// sequence number: 32 bits
	//   This field holds the number of bytes received so far.
	ACKNOWLEDGEMENT = uint8(3)

	// User Control Message
	//
	// The client or the server sends this message to notify the peer about
	// the user control events. This message carries Event type and Event
	// data.
	// +------------------------------+-------------------------
	// |     Event Type ( 2- bytes ) | Event Data
	// +------------------------------+-------------------------
	// Figure 5 Pay load for the ‘User Control Message’.
	//
	//
	// The first 2 bytes of the message data are used to identify the Event
	// type. Event type is followed by Event data. Size of Event data field
	// is variable.
	USER_CONTROL_MESSAGE = uint8(4)

	// Window Acknowledgement Size
	//
	// The client or the server sends this message to inform the peer which
	// window size to use when sending acknowledgment. For example, a server
	// expects acknowledgment from the client every time the server sends
	// bytes equivalent to the window size. The server updates the client
	// about its window size after successful processing of a connect
	// request from the client.
	//
	//  0                   1                   2                   3
	//  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	// |                   Acknowledgement Window size (4 bytes)       |
	// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	// Figure 6 Pay load for ‘Window Acknowledgement Size’.
	WINDOW_ACKNOWLEDGEMENT_SIZE = uint8(5)

	// Set Peer Bandwidth
	//
	// The client or the server sends this message to update the output
	// bandwidth of the peer. The output bandwidth value is the same as the
	// window size for the peer. The peer sends ‘Window Acknowledgement
	// Size’ back if its present window size is different from the one
	// received in the message.
	//  0                   1                   2                   3
	//  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	// |                   Acknowledgement Window size                 |
	// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	// | Limit type    |
	// +-+-+-+-+-+-+-+-+
	// Figure 7 Pay load for ‘Set Peer Bandwidth’
	//
	// The sender can mark this message hard (0), soft (1), or dynamic (2)
	// using the Limit type field. In a hard (0) request, the peer must send
	// the data in the provided bandwidth. In a soft (1) request, the
	// bandwidth is at the discretion of the peer and the sender can limit
	// the bandwidth. In a dynamic (2) request, the bandwidth can be hard or
	// soft.
	SET_PEER_BANDWIDTH = uint8(6)

	// Audio message
	//
	// The client or the server sends this message to send audio data to the
	// peer. The message type value of 8 is reserved for audio messages.
	AUDIO_TYPE = uint8(8)

	// Video message
	//
	// The client or the server sends this message to send video data to the
	// peer. The message type value of 9 is reserved for video messages.
	// These messages are large and can delay the sending of other type of
	// messages. To avoid such a situation, the video message is assigned
	// the lowest priority.
	VIDEO_TYPE = uint8(9)

	// Aggregate message
	//
	// An aggregate message is a single message that contains a list of sub-
	// messages. The message type value of 22 is reserved for aggregate
	// messages.
	AGGREGATE_MESSAGE_TYPE = uint8(22)

	// Shared object message
	//
	// A shared object is a Flash object (a collection of name value pairs)
	// that are in synchronization across multiple clients, instances, and
	// so on. The message types kMsgContainer=19 for AMF0 and
	// kMsgContainerEx=16 for AMF3 are reserved for shared object events.
	// Each message can contain multiple events.
	SHARED_OBJECT_AMF0 = uint8(19)
	SHARED_OBJECT_AMF3 = uint8(16)

	// Data message
	//
	// The client or the server sends this message to send Metadata or any
	// user data to the peer. Metadata includes details about the
	// data(audio, video etc.) like creation time, duration, theme and so
	// on. These messages have been assigned message type value of 18 for
	// AMF0 and message type value of 15 for AMF3.
	DATA_AMF0 = uint8(18)
	DATA_AMF3 = uint8(15)

	// Command message
	//
	// Command messages carry the AMF-encoded commands between the client
	// and the server. These messages have been assigned message type value
	// of 20 for AMF0 encoding and message type value of 17 for AMF3
	// encoding. These messages are sent to perform some operations like
	// connect, createStream, publish, play, pause on the peer. Command
	// messages like onstatus, result etc. are used to inform the sender
	// about the status of the requested commands. A command message
	// consists of command name, transaction ID, and command object that
	// contains related parameters. A client or a server can request Remote
	// Procedure Calls (RPC) over streams that are communicated using the
	// command messages to the peer.
	COMMAND_AMF0 = uint8(20)
	COMMAND_AMF3 = uint8(17) // Keng-die!!! Just ignore one byte before AMF0.
)

Message type ID

const (
	EVENT_STREAM_BEGIN       = uint16(0)
	EVENT_STREAM_EOF         = uint16(1)
	EVENT_STREAM_DRY         = uint16(2)
	EVENT_SET_BUFFER_LENGTH  = uint16(3)
	EVENT_STREAM_IS_RECORDED = uint16(4)
	EVENT_PING_REQUEST       = uint16(6)
	EVENT_PING_RESPONSE      = uint16(7)
	EVENT_REQUEST_VERIFY     = uint16(0x1a)
	EVENT_RESPOND_VERIFY     = uint16(0x1b)
	EVENT_BUFFER_EMPTY       = uint16(0x1f)
	EVENT_BUFFER_READY       = uint16(0x20)
)

User Control Message Event Type

const (
	BINDWIDTH_LIMIT_HARD    = uint8(0)
	BINDWIDTH_LIMIT_SOFT    = uint8(1)
	BINDWIDTH_LIMIT_DYNAMIC = uint8(2)
)

Set peer bandwidth 的 limited type

Functions

func Serve

func Serve()