Sony and Panasonic have announced plans for a successor to Blu-ray discs.
The firms say they want to develop an optical disc capable of holding at least 300 gigabytes of data by the end of 2015.
By contrast, dual-layer Blu-rays can only hold up to 50GB.
Sony has previously said that 4K ultra-high-definition movies - which offer four times the resolution of 1080p video - were likely to take up more than 100GB of space.
It recently launched a device that allows 4K films to be streamed over the internet, but that will be impractical for people with slow internet access or accounts with data-use limits.
BBC News - Blu-ray successor plan unveiled by Sony and Panasonic
The firms say they want to develop an optical disc capable of holding at least 300 gigabytes of data by the end of 2015.
By contrast, dual-layer Blu-rays can only hold up to 50GB.
Sony has previously said that 4K ultra-high-definition movies - which offer four times the resolution of 1080p video - were likely to take up more than 100GB of space.
It recently launched a device that allows 4K films to be streamed over the internet, but that will be impractical for people with slow internet access or accounts with data-use limits.
BBC News - Blu-ray successor plan unveiled by Sony and Panasonic