A fully-annotated imagery dataset of sublittoral benthic species in South Eastern Baltic Sea reefs

The data presented here was collected in SE Baltic Sea coastal and offshore reefs during the sampling seasons of 2020-2021 summer-autumn and 2013 June. Offshore data consists of two 30 s long video samples (DE01-1, DE01-2) that were filmed with ROV mounted Full HD (1920 × 1080) resolution camera with lighting system consisting of 16 bright LED in 4 × 4 stations. Coastal data consists of five 10 m transects (SM02-1, SM02-2, SM07-1, SM07-2, SM08) filmed by SCUBA divers with GoPro camera. The provided dataset consists of three types of data: annotated frames, annotated 2D video mosaics and raw data consisting of video samples and 2D video mosaics. All video samples were converted into still images (video mosaics or frames), that were visually analysed by marine biologists. Mosaic SM08 was divided into two equal parts (SM08-1, SM08-02). Four biological and four geological features were targeted for annotation: red algae Furcellaria lumbricalis and Vertebrata fucoides, green algae Cladophora sp., blue mussel Mytilus edulis trossulus, Boulders (>25 cm), Cobbles (6-25 cm), Pebbles (0.2-6 cm) and Sand (