Footage of a groom playing a video of his bride apparently cheating with her brother-in-law has gone viral in China.

The man had the five-minute sex tape played out on a big screen in front of family and friends to humiliate his unfaithful fiancée after discovering her affair with her pregnant sister's husband, according to online accounts.

The unverified footage, believed to be filmed by a guest at the nuptials, has sparked an outcry among web users. While some believe the incident to be real, others argue that the clips have been used by a video app as a marketing stunt.

Trending footage shows the couple walking down the aisle and then standing on a stage at their wedding banquet. Then the groom allegedly humiliated his partner with a sex tape

The trending topic, comprising three clips, has been widely reported by major Chinese-language media outlets, including Sina from mainland China, Apple Daily from Hong Kong and Ettoday from Taiwan.

According to various reports, the wedding took place in the province of Fujian in south-eastern China last Thursday.

One of the clips shows the lovebirds walking down the aisle and then standing on a stage at their wedding banquet.

An emcee is heard telling the crowd 'now we are going to show you the videos of how the newlyweds grew up'. But seconds later, an X-rated video starts playing from the projector.

The clip then shows the groom accusing the bride on stage 'you thought I didn't know?' and the bride throwing her bouquet at her partner. They are separated by their family members and friends shortly after.

The lewd footage (circled) capture by a security camera was played out in front of the couple's family and friends, it is claimed. The lovebirds had a fight on stage and had to be separated

The two other clips, running five minutes in total, are explicit films said to be of the bride and her brother-in-law.

Apple Daily reported that the couple had been in a relationship for two years and was engaged six months ago, citing accounts from insiders.

It is said that the groom found out about his bride's affair after installing a security camera in their future home during a renovation project.

The report also suggested that the bride's sister was six months pregnant.

According to an influential Chinese entertainment blogger, known as 'Jiang Zhe Hu Ba Jie', the clips first emerged on a short-video app called 'Aubergine Video', therefore the incident was billed as the 'aubergine brother-in-law gate'.

Reports suggest the bride was accused of having an affair with her pregnant sister's husband

The blogger also claimed that the bride cheated on her fiancé after suffering from domestic violence from him.

She allegedly agreed to marry him after he had promised to pay for a flat and a car for their union.

The blogger added that the bride admitted the affair. It is said that she and her brother-in-law developed feelings for each other after the latter started to mediate between her and her fiancé during their dispute over domestic violence.

The bride has demanded her partner withdraw all video clips from the internet, according to the post.

However, another gossip columnist, Mr Zha, believes the whole incident was a marketing stunt.

The writer wondered how the video app had obtained the footage 'exclusively'.

'Who would air their dirty laundry on a video website?' Mr Zha argued.

He also pointed out that the clip played out at the wedding bore the logo of the video app.

'To summarise, there is only one explanation, this is a malicious marketing stunt,' he criticised.

As of writing, clips involving the incident have been removed from Chinese social media platform Weibo, but are still circulating on Twitter and messaging app WeChat.