Projection Protocol Summary

Dlna, short for digital living network alliance, is intended to address multimedia sharing (audio, video, and image) within the LAN of PCs, household appliances, and mobile devices ). It is too far-fetched to say that dlna is a multi-screen interaction. Specifically, it should be media sharing technology. The following conditions must be met when using the dlna function:
The device must be in the same LAN;
At least one DMS and one DMP are required.
Dlna products:
1. DMS stands for digital media server. It refers to the multimedia files in the device (which files need to be shared by itself) to the dlna server,
2. DMP, short for Digital Media Player, can search for all multimedia content provided by DMS in the LAN and play it on this device.
3. DMC, short for digital mediacontroller, is used as the control DMP to search and play the content of DMS. Unlike DMP, DMC can control the interaction between DMS and DMP of other devices in the LAN. For example, pad is used as DMS, set-top box is used as DMP, and mobile phone is used as DMC. The three devices are in the same LAN, and the mobile phone can directly control the multimedia shared in the set-top box playing pad.
DMR, short for digital render. function: DMP + DMr.
Common Product Planning: set-top boxes are used as DMP, audio devices, mobile phones, and tablets as DMS, and mobile phones as dmns. In fact, DMR is generally developed on mobile phones. This is the common DMS + DMR development on the market. Applications with complete functions should include these two functions.
Part 2. Main body: the development process of dlna in Android. This document ignores some details and only describes the core steps:
1. dlna is based on the UPnP protocol, so you should select an open-source third-party UPnP SDK to use the core processing of dlna. URL: Success .. Yes
2. Refer to the UPnP SDK documentation for the corresponding core development. The general process of those sdks is to compile a JNI library.
3. Use the JNI library for Android Application Layer Development.
4. Here I will talk about the development of DMP separately. For various reasons, the video that dlna can transmit is very limited and Android has been very criticized for video processing, google's video processing API mediaplayr is very weak in video processing. If you want your application to provide excellent support for various videos, you are advised to keep a video player and FFMPEG gstream VLC.
The entire development process is the JNI development under ndk. Of course, except for some sdks, there are sdks specially processed by Java.
We recommend several good UPnP sdks below:
Cling platinum cybergarage (This SDK is used by hith)
The specific development technology is included in the corresponding SDK development documentation. Below are some good blogs:
1. For the implementation tutorial of the DMS application layer with platinum, The JNI library does not have the source code and can be compiled by itself:
Http://blog.csdn.net/lancees/article/details/9865411
Good introduction to UPnP and development of dlna ideas
Http://blog.csdn.net/bao_jinyu/article/category/1149905
Developers must know how to select good items on GitHub
Https://github.com/
Dlna applications developed based on cling
Http://www.it165.net/pro/html/201303/4968.html
5. dlna development based on the cybergarage library. This SDK is used by The Hais dlna application.
Http://luochao0913.blog.163.com/blog/static/6409386120133104208719/
Part 3. Other knowledge about dlna
Differences between dlna, miracast, and airplay protocols, advantages and disadvantages, and implementation methods
Dnla was initiated by Sony, Intel, and Microsoft. At that time, Apple was also a member of the dlna alliance, and later withdrew and made a stand-alone portal. Dlna and Apple's airplay functions are similar, and the Protocols are similar. They all allow media content on your mobile phone to be delivered to the TV screen. The difference is that the dlna on the mobile phone does not have the airplay image function similar to Apple TV, nor does it have the dual-screen game experience supported by Apple TV. Currently, dlna can only send photos and videos from mobile phones to large screens.
Miracast is a wireless display standard based on Wi-Fi direct connection established by the Wi-Fi Alliance in 2012. Devices that support this standard can share video images wirelessly. For example, a mobile phone can use miracast to directly share videos or photos on a TV or other device. Unlike dlna, miracast also has an image function similar to airplay, which allows you to directly place the screen content on a mobile phone to a HDTV screen, so that you can play games on a TV screen. As this technology is relatively new, devices supporting this technology are very rare so far. In addition, the technology is not mature, and even the miracast of Xiaomi box is still under development.
Airplay is a wireless technology developed by Apple, you can transmit images, audios, and videos from IOS devices such as iPhone, iPad, and iPod Touch to airplay devices wirelessly through WiFi. Airplay also has a special feature called airplay image, which works with Apple TV to wirelessly transmit pictures on the iPhone or iPad to the TV, that is to say, what TV screen is displayed on your device, not just pictures and videos. Therefore, it is cool to use this function to play games. You can use iPad as the steering wheel and watch the screen play games. In addition, the most powerful aspect of airplay images is that they can implement dual-screen games and allow more interaction between your games.
Dlna Protocol: This Protocol is applicable only to audio, video, and image pushing. It transfers multimedia files to a TV or projector wirelessly.
Miracast Protocol: it is a wireless display standard based on WiFi direct connection. Devices that support this standard can share video images wirelessly. For example, a mobile phone can use miracast to directly play a video or photo on a TV or other device without being affected by the length of the connection cable. Miracast and airplay are the same image functions. They can direct the screen content on a mobile phone to a HDTV screen. You can also play games and play online videos on a TV screen.
Airplay Protocol: currently, Apple airplay only applies to authenticated Apple devices, currently, Apple's devices support this technology, including iPad, iPhone, and Apple TV. In addition, there are some devices authorized by Apple's partners, for example, provide technology-authorized audios to pioneer and Sony.

==== Dlna protocol problem ===== http://blog.csdn.net/lancees/article/details/18269109