FREQUENTLY ASKED QUESTIONS
Can you describe the process?
- A digital copy of the original recording is created and the original returned to the source for evidence and storage. It is important to work from a digital backup, since original recordings are degraded by continuous replay. With our methods, the original recording is never altered or damaged in any way. When we start any enhancement, it is critical that we start with original recording. Even a first generation copy involves the loss of thousands of critical pixels that it can never be available for processing.
- The part of the tape containing the important subject matter is isolated; the frame sequences are mapped and converted into digital stills.
- All usable frames are resized and reoriented to isolate the subject matter. This is necessary when either the subject or camera is in motion, or the zoom feature of the camera was in use at the time of the filming.
- Every pixel within every frame is analyzed and recorded into a database. Using DoubleTake's proprietary software, pixels from successive frames are either averaged, eliminated or ignored.
- The software then reconstitutes a single frame based on the best information available on all the analyzed frames.
- The final frame is then enhanced with traditional sharpening and gamma curve modification.
- An 8x10 photographic print onto Kodak paper is produced and returned to investigators.
Does the use of a zoom lens make successive frames unusable?
Generally not. Because the use of a zoom lens does not involve any change of perspective of the subject (only its magnification), the software can identify and compensate for this movement.
Does camera shake or movement make successive frames unusable?
If the movement is due to incidental or mild camera shake where the perspective has not significantly changed, the software can compensate. If the shake is severe, resulting in blurred images within a frame however, that particular frame is likely to be unusable and will be automatically eliminated from the procedure.
Does the movement of the subject degrade the analysis process?
Sometimes. When resolving finer details of a person's face, it is necessary to find at least ten successive frames in which the subject has moved relatively little. Slight camera movement and subject movement can be compensated for, but if the subject is rapidly turning his head or changing perspective relative to the camera, this can be a problem.
Can you improve blurred or out of focus images?
Generally not. There is no reliable technology that is able to replace pixels that have been severely blurred. However, we do use conventional sharpening techniques that can improve images between 10% and 20%
Are results predictable?
No. The results depend on too many factors. The type of film or tape used, type of equipment, types of lenses, subject movement, camera movement, lighting conditions etc. Depending on these variables, results are unpredictable, but almost always, we can reveal details that were otherwise invisible. Paradoxically, the higher the image quality of the original recording, the more difficult it is to improve. The most dramatic results come from low light, high noise videotape which has many frames of the subject.