Learn Linux dlna with cainiao

About the dlna framework

 

1. Networking & connectivity

To solve the connectivity problem of physical devices,

It mainly depends on Ethernet, 802.11, IPv4 protocol stack, and IPv6 protocol stack.

The TCP/IP protocol stack must contain IPv4, TCP, UDP, DHCP, auto-IP, ARP, and ICMP.

2. device discovery & Control

To solve device discovery and interoperability problems, the so-called "device Zero Configuration" is implemented ". For example, when playing PC media through a TV, the TV device needs to "automatically know" the existence of the PC Media Server and what services it can provide.

It mainly depends on UPnP Device architecture standards, XML, SOAP, and HTTP.

3. Media Management

Manage and distribute media logos.

Depends mainly on the UPnP AV V1.0 Specification

Contentdirectory (DMS ):

Browse/find all media files

Including metadata, such as title, creator, and resolution.

Manage content, such as creating a playlist and adding a new project.

Renderingcontrol (DMP ):

Controls the features of rendering, such as volume and backlight.

Connectionmanager (DMP, DMS ):

List supported transmission protocols and data formats

List existing UPnP AV streams

AV transport (DMP, DMS ):

Control activities and locations, such as playing, pausing, fast forward, and fast return.

4. Media transport

The solution is to "stream" media content on the server to the media presentation end.

Depending on http1.1, the media stream is closed by closing the TCP connection.

 

5. Media Formats

It solves the problem of how to encode and flag media content.

Media Format profiles and media interaction rules are defined.

The specific process of miniserver is as follows:

DMR callback Handler

DMS callback Handler