Abstract

At this stage, compared to the situation before 2010, documentaries in China are what video production practitioners call "three high" content (the viewing group is mostly high class, high education, high income), with a high barrier to integration into the circle. The difference with the popularity of documentaries on the internet is that before the onslaught on video sites and UGC platforms, documentaries were basically the "exclusive content" of television stations. This continued downturn was reversed in 2012 and has led to a shift in the audience for documentaries towards the masses. It is worth exploring how traditional television platforms have broken down the barriers and what the reasons for this turnaround are. Unlike the traditional TV media, B-site is a commercial short-form video streaming platform that gathers a large number of secondary culture users and has a fixed cultural circle, so it is worthwhile to analyse and learn from the reasons why B-site, which has a fixed cultural circle, was able to break the culture of the circle and achieve cross-circle communication with a documentary film on food with vertical content, "A String of Life", and win traffic for itself. It is worthwhile for us to analyse and learn from this.

This paper takes the commercial short video medium "Bilibili", referred to as "B-site", as the research object, and selects a food-themed online documentary "A String of Life" produced by B-site and Banner

Media as the key research object. This paper takes the commercial short video medium "Bilibili" as the research object, and selects a food documentary "Life in a String", which is produced by B-site and Banner Media, as the key research object. Through the method of literature review, for a large number of relevant journals, papers, writings and other literature to read and organize, article integration, and to summarize them, to recognize the development process and the current situation of web-based documentary film, to lay the foundation for a proper background study of this paper. The methods of the content quality assessment are used to categorize the existing B-site web-based documentaries into different sections and classes according to their contents and themes. Focusing on the innovative creation of the video content of the first and second seasons of "A String of Life", collating and analysing its content creation points, and exploring the content innovation points of the B website online new school documentary "A String of Life". Firstly, a survey was conducted to summarise the exposure channels and needs of university students for documentaries, secondly, the phenomenon of the circle communication presentation of the food pendant documentary "A String of Life" was studied by using the theory of circle communication, followed by an analysis of what are the communication performances of the web-based documentary "A String of Life", again, the reasons why "A String of Life" can successfully achieve