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Salient Stills has made great strides in simplifying the processes that often need to be applied to forensic, legal, or security video. The recently released VideoFOCUS Pro 3.0 demonstrates that real power is not in complexity; rather, its in high performance and deep functionality accessed through an easy-to-learn interface.
VFPro can acquire video that comes with or without audio tracks. The application requires nothing more than a Windows XP PC. It can capture DV direct from an OHCI compliant FireWire port or from a Direct Show compliant capture card. (Salient Stills recommends Blackmagic Design DeckLink cards.) You can import most common media file formats or use its screen capture function to grab video from proprietary digital video player applications.
I used a software only installation: All my test video was acquired by screen capture or file import. The acquisition process is straightforward, and the program as a whole is simple to use, early to learn for novice and expert alike.
VFPro has five menus, with most of what forensic video specialists will need in the Processing menu. Many sessions will use the Super Resolution feature to produce stills for use at trial or identification purposes.
The Create Still dialog does a number of things in a single operation. It displays seven frames, three preceding and three succeeding the frame of interest, and indicates the relative strength each image will play in averaging to get the final still. A slider allows you to control how much the adjacent frames will contribute.
The neatest part of the dialog is the Create Masks button, which allows you to create, size, move, and invert a mask to track, stabilize, and improve detail visibility of a moving object in the scene. It even does well with interlaced video where motion blur can totally obscure, for example, the license plate on a passing vehicle.
Click the Create Still button and it generates a huge picture (by default scaled for full-page printing at 300 dpi) so you can look for details not readily visible at standard video resolutions. If you prefer a different size and print density, you can set that in the dialog, then click Create Still again. Once you do this, a thumbnail of the still is placed in the Session Stills and Frames area of the main window, from which you can export or print it.
The other Processing sub-menu items are modify, filter, and demultiplex. The modify dialog provides a preview player, interlacing control, and panels for changing spatial and temporal properties. Because all processing is non-destructive to the acquired media, the dialog allows you to create a new media clip or session.
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WAYNE COLE
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The filter sub-menu offers selections for grayscale, sharpen, equalize, blur, stabilize, and levels adjust. All filter dialogs have side-by-side input and output viewers with basic transport controls, so you can gauge the filters
effect on the selected clip. Plus, all filters (except stabilize) feature mask tools that allow you to limit portions of the picture to which the filter will apply. Click the Save Video button on any of the filter dialogs to create a new session again, non-destructive processing is the key.
I have primarily used semi-automatic demuxers, where I have to seed the demux process by identifying one frame from each distinct view in the multiplexed source. It took me a little while to get used to VFPros fully automatic demuxing. Yes, you can manually demultiplex video, but the process works more efficiently if you recursively apply demuxing.
After a demuxing pass, there are usually some views with very few frames in them. You can either drag them to the views to which they belong (and VFPro automatically inserts them in the proper temporal order) or you can use the Reassign Frames to Existing Views option to automate the process. You can manually drag and drop individual frames or ranges of frames to any other existing view or to a new view. But for more than one or two errant frames, this is the least efficient approach given the power of VFPros automatic demuxing ability.
You are often challenged in court on what you did to produce an image months or years after you actually did the work. My memory certainly benefits from records of processing generated at the time the processing occurs. VFPro creates these records and stores them with each session and still you make. You can see a hierarchical audit report on the selected session or still and you can save the audit file and examine it later with a simple text editor.
VideoFOCUS Pro 3.0 is a winner. Its powerful, produces quality results, is non-destructive to the source media, and creates a detailed audit of your media processing. Plus, its not dependent on any specific editing system or image processing software. ★
Wayne M. Cole, CCV, CLVI, and member of the AGCV Board of Advisors, is also the owner of IHP, a video production company located Santa Barbara, CA. Contact him at wcole@ihpweb.com.
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