Analysis on Mogujie.com live broadcasting architecture (1)

About live broadcasting
The primary features of live broadcasting are its real-timeliness and interactiveness, which also differentiate live broadcasting from on-demand video streaming. It can transmit video information from the broadcaster side to the audience side with low latency. At the same time, the audience can interact with the broadcaster through group chats or by sending gifts.
Figure 1
Live broadcasting is composed of the following major procedures (see Figure 1):
1. Video capture on the broadcaster side
2. Processing: Beautify, watermarks, face-recognizing animated stickers;
3. Encoding: The videos are mainly H264-encoded;
4. Pushing stream: RTP is adopted, such as RTSP, RTMP and HLS;
5. Network transmission: Empowered by CDN services;
6. Pulling stream: Transcoding required on the service side. Multi resolutions and RTP are supported;
7. Decoding: Hardware decoding or software decoding is enabled;
8. Playing.
A vast majority of the above procedures are undertaken by cloud services. The face-recognizing animated stickers feature independently developed by Mogujie.com is incorporated in the pre-processing. Both the pre-processing and playing are empowered by the open-source GPUImage library.
Mobile live broadcasting form
The live broadcasting form and framework
Currently, the mobile live broadcasting forms can be divided into the following categories: Live broadcasting for all, live broadcasting for social-networking, live broadcasting for e-businesses and live broadcasting for mobile games. Mogujie.com mainly offers the live broadcasting for e-businesses. Next we will mainly introduce the composition of Mogujie.com live broadcasting.
Figure 2 outlines the composition of Mogujie.com live broadcasting in three major modules, namely the media module, the service module and the management module.
1) Media module
This module is composed of live broadcasting and live broadcasting playback. The playback of live broadcasting has two objectives: one is to accumulate high-quality content on the platform; the other is to enrich the platform content by providing the playback of some live broadcasts during the periods when there are less new broadcasts.
2) Service module
It is also called the business module, including e-business, payment, chat, gift, operation, lucky draws, safety and statistics systems.
Among them, the e-business system (see Figure 3) is a system unique to Mogujie.com and serves to enable sellers to launch new products and issue discount coupons during live broadcasts. It focuses on the commodity channel and the audience will be able to browse commodities, add commodities to the shopping cart, place an order, make the payment and get the discount coupons. The window size on the audience's side can be switched at will, facilitating convenient consumption for the audience. They can watch the video while making purchases. This module is successful, both product-wise and technically. The statistical data shows most of the deals made in the live broadcasting rooms are from the purchasing orders when the audience switches from the live broadcasting room to the details page.
3) Management module
The management module is mainly used for background management.
Live broadcasting pages of Mogujie.com can be primarily divided into the broadcaster side pages and the audience side pages. Figure 4 comprehensively shows the broadcaster side page of Mogujie.com live broadcasting.
Figure 5 is the broadcaster information page, below which displays the featured products and their prices.
At the bottom of the page in Figure 6 lists the modules for the face recognition/sticker, e-business, resolution-switch and beautify functions. Among them, the e-business module is mainly used by the broadcaster to display products. Regarding the resolution, the default setting is Standard Definition (960P). Viewers can switch to High Definition (1280P)/Smooth (640P).
Figure 7 comprehensively shows the audience side page of Mogujie.com live broadcasting.
As shown in Figure 8, the major difference between the audience side and the broadcaster side is the switching of window sizes (the second module from left at the page bottom). When this feature is enabled, the video window will be switched to a smaller window which can be dragged to a desired place on the screen.
Click to open the e-business module (Figure 9) and the complete commodity information can be displayed (price, name and specification). Viewers can add commodities to the shopping cart and place an order immediately. For example, if you click on the commodity information, the page will directly jump to the details page and the video will be played in a small window. At this time, the audience not only can watch the broadcaster introducing his/her own products, but also check out the major product features intuitively and clearly through images and text. This is also why most of the deals or orders made during the live broadcasting are from the details pages on the Mogujie.com platform.