Mrs Smith, in Phuket on a work trip, was stabbed to death during a botched bag snatch in Kata Noi last Wednesday evening.
She died within minutes of the stabbing, which pierced her heart.
Police today issued a sketch of the man they believe killed her, putting his age at 25 to 30, and his height at 175 to 180 cm.
The video shows two women, Mrs Smith (in a white dress) and fellow travel agent Tammee Lynn, who was also slashed in the attack, walking down the road.
Two men riding a motorbike pull up and the passenger grabs Mrs Smith’s handbag.
Mrs Smith is seen struggling with the thief as Ms Lynn comes to her aid. The bag-snatcher gets off the bike and is seen slashing at the two women.
The killer then runs out of camera view to the motorbike and the pair drive away empty-handed.
The women are seen walking away out of camera view, apparently unaware at that point that they have been injured, though after a few steps Mrs Smith can be seen checking her chest.
She died very soon afterwards, at the service entrance to her resort. Her funeral is to be held on Saturday (June 30) in Australia.
Police held a reenactment of the attack yesterday (June 23) in the hope that it might jog local memories,and a B300,000 reward is being offered for information leading to the man’s capture.
Anyone with information can call any police station or call Phuket Police Commander Maj Gen Chonasit Wattanavrangkul at 081 844 9559.