Coastal Marine Geology Program Video and Photograph Portal

Formatting: After video and/or photographic imagery is acquired from its source (the principal investigator of a survey, survey technicians, archives or other USGS databases), the imagery is manipulated and reviewed to ensure it is “portal-ready.” Videos and photos containing extraneous frames, such as boat deck shots, extensive water column sequences, blank or distorted imagery from equipment malfunction, and other content not directly relevant to seafloor and coastal understanding is removed. The imagery must also be edited to meet proper file formatting and resolution for its publication in the portal. Raw video files recorded during surveys may be too large and/or an unsuitable format for web-streaming. Video are compressed to a standard codec (such as MPEG-4) and uploaded in a suitable container (such as MP4) so that the videos meet the necessary YouTube specifications. Compressing the video reduces the file size, thus making web-streaming feasible, while only slightly reducing video quality of the original recording. Other video processing steps may include stripping audio tracks and creating video text overlays displaying survey information such as survey ID, date, and station. Older video collected on film is converted to digital format to enable it to be uploaded to the portal. Video stored in DVD format, which contains multiple different files (such as VOB files) for a single video, is reformatted to a single video file with the standard codec and container. File type reformatting is generally not required for photographs, as Picasa, the web-hosting platform for photographs in the portal, accepts a wide range of standard image file types. Photographs published in the portal contain exchangeable image file format (Exif) metadata tags. These tags are either created during collection by the recording equipment or are added during processing stages. During processing, photographs are checked for Exif information including: credit for creation, contact information, geographic coordinates, and tags may also contain summary information about the survey. This metadata can be used to identify, locate, and provide contact information for a given image. Photographs that do not already contain the proper Exif metadata for the portal are updated using a set of processing tools described below.

Imagery formatting tools: Multiple tools are used to edit, format, review, and upload imagery to the portal. These include video and photograph editing software, command-line tools, and computer scripts. Editing, formatting and compressing videos is accomplished using command-line functionality from the free software project FFmpeg. The software meets most processing requirements for the videos, and can trim extraneous video frames, remove or edit audio tracks, create text overlays, cut a single video into multiple videos, concatenate videos, as well as convert codecs, containers, filters and compress videos as required by the data. ExifTool, another free software project, provides command-line functionality to edit a photo’s Exif metadata tags. For this purpose, the ExifTool has been incorporated into Python scripts, allowing large numbers of photos to be edited with data from spreadsheets containing geographic coordinates, citations and summary text. Other Python computer scripts have been written that also utilize ExifTool, FFmpeg, as well as standard operating system tools, to edit, name, catalog and organize video files.

Uploading: After navigation records are compiled and completed for all imagery, the photographs and videos are uploaded using scripts written and provided by the portal’s web developing contractors. Additional structured query language (SQL) scripts then create a final spreadsheet record containing internet links to imagery (such as YouTube IDs and Picasa Album and image IDs), latitude, longitude, and the number of seconds into a video for every row in the record. This final record with imagery and location is shared with the contractors, and the data is added to the interactive portal. Additionally, metadata and a summary of the survey with links to publications and funding programs is uploaded for each YouTube video, and a summary of the data with links is added to the portal’s data catalog web pages. Surveys in the portal’s data catalog are organized and grouped according to geographic regions and survey themes.

Keywords section of metadata edited for consistency across the USGS Pacific Coastal and Marine Science Center and to further optimize discovery in search engines and data catalogs. Metadata was modified to bring up to current USGS PCMSC standards. Minor typos were corrected. No data information was changed.

Edited metadata to add keywords section with USGS persistent identifier as theme keyword. No data were changed.