The man carrying the wounded soldier was a Lancashire Fusilier, and can be identified from his uniform badges and insignia.
The Imperial War Museum recently conducted an enquiry into the identity of the soldier, after being supplied with a possible name. The film was forensically examined and a picture of the 'suspect' was superimposed over the top of the original footage.
This revealed that they were, in fact, two different people, so he remains unidentified.
It has been reported (as stated above) that the wounded soldier died about 30 minutes after the photograph was taken. How that has been established, is a mystery, as presumably, the identity of the soldier would be known, but his name is never disclosed.
In similar footage, an Officer can be seen supervising troops entering a trench system on their way into battle. The soldiers are coming head-on towards the camera, and then turning left (as you look at the screen) with the Officer, complete with Greatcoat and cap, to the right of the picture.
This Officer has now been positively identified. In fact a forensic lip-reader has analysed the footage and reported the conversation that takes place, as the troops pass by.
His grand=daughter was recently invited to examine the footage, and a film was made of the whole event.
Riveting stuff. 'We will remember them'