Motion Picture Film Image Stabilization Method and System
20250247492 ยท 2025-07-31
Inventors
Cpc classification
International classification
Abstract
The present invention provides a motion picture film image stabilization method that uses (a) a coincident exposure process to capture a predetermined number of marked frames of a film wherein each marked frame includes a marked image and fiducial mark(s); (b) developing the film; (c) digitizing the film to convert each of the marked frames into a digital marked scan having a digital image of the marked image and the digital fiducial mark(s); and repositioning each digital image of each digital marked scan using dimensional position of the digital fiducial marks. This method can be achieved via the present invention's system comprising a motion picture film camera, a fiducial system, a scanner, and a processor.
Claims
1. A motion picture film image stabilization method comprising: using a coincident exposure process to capture a predetermined number of marked frames of a film wherein each of the marked frames includes a marked image and at least one fiducial mark associated with the marked image, wherein the coincident exposure process to capture each of the marked frames includes: exposing an image of external environment onto exposed film portion of the film using a motion picture film camera during a film hold period resulting in the marked image contained within the marked frame; and exposing at least one fiducial marking means onto unexposed film portion of the film using a fiducial system during the film hold period resulting in the at least one fiducial mark also contained within the marked frame, thereby being associated with the marked image contained within the marked frame; developing the film having the marked frames; digitizing the film using a scanner resulting in digital marked scans of the marked frames wherein: the marked image of each of the marked frames is digitally converted into a digital image; and the least one fiducial mark associated with the marked image is digitally converted into the at least one digital fiducial mark; and repositioning the digital image contained within each of the digital marked scans translationally using dimensional position of the at least one digital fiducial mark shown on each of the digital marked scans to provide a 2-dimensional stabilization of the digital image.
2. The method of claim 1 wherein there are at least two of the digital fiducial marks and the digital image is stabilized by repositioning the digital image via translation and rotation of the digital image.
3. The method of claim 1 wherein the digital image is translated both vertically and horizontally.
4. The method of claim 1 wherein the film hold period is defined as the period of time while the film is being held motionless in a film gate of the camera resulting in the marked frame containing both the at least one fiducial mark and the marked image.
5. The method of claim 1 wherein during the film hold period, the exposing an image of external environment onto exposed film portion of the film process occurs before the exposing the at least one fiducial marking means onto unexposed film portion of the film process.
6. The method of claim 1 wherein during the film hold period, the exposing an image of external environment onto exposed film portion of the film process occurs after the exposing the at least one fiducial marking means onto unexposed film portion of the film process.
7. The method of claim 1 wherein during the film hold period, the exposing an image of external environment onto exposed film portion of the film process occurs simultaneously with the exposing the at least one fiducial marking means onto unexposed film portion of the film process.
8. The method of claim 1 wherein the at least one fiducial mark is located adjacent to the marked image.
9. The method of claim 1 wherein the at least one fiducial mark is not located adjacent to the marked image.
10. The method of claim 1 wherein the fiducial system is incorporated into a motion picture film camera; and the fiducial system includes at least one fiducial marking means and a light source assembly that provides light need for exposing the at least one fiducial mark onto the unexposed film portion of the film during the film hold period.
11. A motion picture film image stabilization system comprising a motion picture camera having a fiducial system wherein: during an image capturing process, the camera captures images of an external environment onto exposed portion of a film by exposing the exposed portion of the film to light coming from the external environment during film hold periods, resulting in marked images contained in marked frames; during a fiducial mark capturing process, the camera, assisted by the fiducial system having at least one fiducial marking means and a light source, captures at least one fiducial mark onto unexposed portion of the film during film hold periods by the camera, resulting in the at least one fiducial mark contained in each of the marked frames; the image capturing process and the fiducial mark capturing process for each of the marked frames are coincident resulting in each of the marked frames having both the marked image and the at least one fiducial mark associated with the marked image; and each of the film hold periods is a period of time when the film is being held motionless in a film gate of the camera for completion of both the image capturing process and the fiducial mark capturing process for each of the marked frames.
12. The system of claim 11 further comprising: a film development process system that develops the marked frames; a scanner that digitizes the marked frames into digital marked scans wherein each of the digital marked scans contains a digital image of the marked image, and a digital at least one fiducial mark that is a digital representation of the at least one fiducial mark corresponding to the marked image; and a processor that stabilizes the digital image of the marked image of each of the digital marked scans translationally by repositioning each of the digital marked scans based upon dimensional position of the digital at least one fiducial mark to provide a 2-dimensional stabilization of the digital image.
13. The system of claim 12 wherein the fiducial system provides at least two of the digital fiducial marks, and the digital image of the marked image of each of the digital marked scans is stabilized by repositioning each of the digital marked scans via translation and rotation.
14. The system of claim 11 wherein the fiducial system is incorporated into the camera; and the fiducial system includes at least one fiducial marking means and a light source assembly having a light source having an illuminant that provides light needed for exposing the at least one fiducial mark onto the unexposed film portion of the film during the film hold periods.
15. The system of claim 14 wherein the illuminant is selected from the group consisting of a light emitting diode LED, a laser diode, an electroluminescent device, an incandescent bulb, and a fluorescent bulb.
16. The system of claim 14 wherein the light source assembly further includes an electrical control means and the illuminant is electrically modulated by the electrical control means.
17. The system of claim 14 wherein the illuminant is unmodulated.
18. The system of claim 17 wherein the light source assembly further includes a light modulator that modulates the light coming from the illuminant, wherein the light modulator is selected from a group consisting of: an electrically controlled light modulator controlled by the electrical control means; and a mechanical light modulator that allows the light coming from the illuminant to pass intermittently.
19. The system of claim 14 wherein the light source includes an optical fiber having a first end that is illuminated by the illuminant and having a second end that provides the light needed for exposing the at least one fiducial mark onto the unexposed film portion of the film during the film hold periods, wherein the second end of the optical fiber also acts as the at least one fiducial marking means.
20. The system of claim 14 wherein the light source further includes a lens to focus light provided by the illuminant.
Description
BRIEF DESCRIPTION OF THE DRAWING
[0014] The present invention will be more clearly understood when considering the accompanying drawing of which:
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DESCRIPTION OF THE PREFERRED EMBODIMENT
[0034] The present invention provides a motion picture film image stabilization method 100 that does not rely on the positional accuracy of the perforations 16 and/or edges 18, or the captured image's 12 content (e.g., no need for the content to have a selected element 62). Instead, and referring to
[0035] During the film hold period for the marked frame 74, the film 10 is being held motionless in the film gate 32 so it is also motionless with respect to the camera lens 24. The marked image 72 is basically the same as the image 12 captured during the conventional motion picture filming process. The novel process of capturing both the fiducial mark 70 and its associated marked image 72 during the film hold period is hereinafter referred to as coincident exposure process 110.
[0036] The shape and sharpness of the at least one fiducial mark 70 are not critical. For example, the fiducial mark's 70 shape could be a circle, rectangle, cross, etc. While it is preferable for the fiducial mark 70 to have relatively sharp edges, it is not critical because modern image analysis techniques as known in the art can accurately determine the center of an isolated captured fiducial mark 70 with an accuracy that far exceeds the sharpness of the edges of the fiducial mark 70 itself (e.g., by using image processing techniques such as centroid determination which are well known in the art).
[0037] While the method 100 can be done with only one fiducial mark 70 being associated with the marked image 72, the image repositioning process 116 of the marked image 72 discussed below is more effective using two or more fiducial marks 70. Accordingly, the discussion hereinafter and the corresponding
[0038] It should be noted that the fiducial marks 70 don't necessarily need to be exposed/captured at exactly the same time as its associated marked image 72 for that the marked frame 74 as long as the fiducial marks 70 are exposed/captured while the film 10 is held motionless in the film gate 32 (i.e., during the film hold period) for the marked frame 74. Accordingly, during the film hold period, the fiducial marks 70 can be exposed/captured before, during, or a little after its associated marked image 72 is exposed/captured.
[0039] Referring to
[0040] As noted above, the capturing of the fiducial marks 70 for the marked frame 74 must occur while the film 10 is in the same fixed position that it will be in for the capturing of the marked image 72 of such marked frame 74 (i.e., during the film hold period), resulting in the fiducial marks 70 being associated with the marked image 72. Basically, this fixed position requires no advancement of the film 10 to the next film frame position. The key here is that the film 10 does not move between the time that the marked image 72 is exposed/captured and the time that the fiducial marks 70 are exposed/captured for the marked frame 74.
[0041] After this coincident exposure process 110, the method 100 further includes developing of the film 10 containing the marked frames 74 using conventional method(s) well known in the arts.
[0042] Referring to
[0043] This digitizing process 114 of the method 100 is achieved using the scanner 50 or any other art-disclosed motion picture film scanning system (see e.g.,
[0044] The method 100 may optionally include having the scanner 50 to also use traditional physical and/or digital image stabilization techniques to approximately stabilize the digital marked scan 76 with respect to the perforations 17 and/or the edges 19.
[0045] The method 100 includes using a digital image repositioning process 116 provided by an art-disclosed processor 81 to process each of the digital marked scans 76 by using conventional methods and techniques to reposition and stabilize the digital marked scan 76 (thus also the digital image 80 contained within the digital marked scan 76) based the dimensional position of the digital fiducial marks 78. The method 100 finds the digital fiducial marks 78 and translates and optionally rotates each digital marked scan 76 so that the digital fiducial marks 78 are moved to their fixed reference positions. Because the fiducial marks 70 are placed in a fixed position relative to the marked images 72 during the coincident exposure process 110 discussed above, the digital images 80 of the marked images 72 will also be stabilized from one digital marked scan 76.sub.(n) to the next digital marked scan 76.sub.(n+1).
[0046] Referring to
[0047] The coincident exposure process 110 can be achieved by incorporating a fiducial system 86 into the camera 14 to capture the fiducial marks 70 onto the unexposed film portion 48 of the film during each of the film hold periods. Referring to
[0048] The fiducial marking means 66 can be any art-disclosed device or method to assist the light source 90 in exposing/capturing the fiducial marks 70 onto the unexposed film portion 48 of the film 10 during the film hold period.
[0049] The marker lens 94 can be any art-disclosed lens suitable for focusing the light source 90 onto the unexposed film portion 48 (e.g. a conventional lens, a gradient index (GRIN) lens, or any other light focusing mechanism). During the coincident exposure process 110, the marker lens 94 focuses the desired light 95 provided by the light source 90 onto the unexposed film portion 48 of the film 10 through the small marker aperture 96 (which acts as the fiducial marking means 66). Typically, light source 90 is electrically modulated by the controller 92 allowing the light source 90 to flash the light 95 for a predetermined amount of time resulting in appropriate exposure on the unexposed film portion 48. The timing of the exposure flash of the light 95 is controlled by a synchronization signal 98 received from the camera's (14) motor control 102 which is responsible for the camera's (14) synchronous operation of its rotating shutter 42 and claw mechanism 40.
[0050] A typical sequence of the coincident exposure process 110 involves the camera 14 holding the film motionless in film gate 32, rotating the shutter 42 to its open position to allow the light 44 to expose the exposed film portion 46 of the marked frame 74.sub.(n) to capture the marked image 72.sub.(n) while the light source 90 flashes the light 95 to expose the fiducial marking means 66 (e.g., the small marker aperture(s) 96) onto the unexposed film portion 48 of the marked frame 74.sub.(n). Thereafter, the camera 14 rotates the shutter 42 to its closed position to block the light 44 and actuates the claw mechanism 40 to advance the film 10 to the next image position 72.sub.(n+1). This process is repeated every time that the camera 14 is used to capture the external environment. The coincident exposure process 110 results in the position of the fiducial marks 70 being captured in a fixed position relative to their associated marked images 72. Accordingly, the fiducial marks 70 are in a fixed position relative to all the associated marked images 72. A modification of this sequence allows for the possibility that the light source 90 can flash a little before, during, or after the associated exposure of the marked image 72.sub.(n).
[0051] In another variation of this sequence of the coincident exposure process 110 and referring to
[0052] In another exemplary embodiment of the fiducial system 86, the light source 90 is placed sufficiently far that the light 95 simply casts a shadow of the marker aperture 96 (i.e., the fiducial marking means 66) in the film gate aperture plate 38 onto the unexposed film portion 48 of the film 10. This is done without needing the marker lens 94.
[0053] Referring to
[0054] Referring to
[0055] If only one fiducial mark 70 of the marked frame 74 is captured by the method 100 resulting in one digital fiducial mark 78, then the associated digital image 80 of the same marked frame 74 can be translated in two dimensions. A single digital fiducial mark 78 limits easy access to rotation information required to rotate the digital image 80.
[0056] However, the fiducial system 86 can capture more than one fiducial mark 70 with more than one fiducial marking means 66 and/or additional light source (e.g., two LEDs 90 as shown in
[0057] It should be noted that the method 100 is applicable to all motion picture film formats (e.g., 8 mm, Super 8 mm, 16 mm, 35 mm, 65 mm, 70 mm, etc.) and to all image sizes on those formats (e.g., Super 16 mm, 4-perforation 35 mm, Super 35 mm, VistaVision, 5-perforation 65 mm, IMAX 8-perforation 65 mm, IMAX 15-perforation 65 mm, etc.).
[0058] The method 100 of the present invention provides many advantages including but not limited to: (i) the accuracy of the image stabilization can be increased to levels which are not attainable through the use of physical film features such as the location of perforations 16 and edges 18, (ii) the manufacturing tolerances for the perforation and cutting of film during manufacture can be relaxed resulting in lower costs, (iii) the tolerances of the motion picture camera film handling mechanism can be relaxed to allow more variability in the frame to frame film position resulting in lower costs and reduced camera noise, (iv) the tolerances of the film scanner mechanism can be relaxed resulting in lower cost, (v) the stabilization process is fully automated, requiring no manual intervention at any point in the process.
[0059] While fiducial marks have been placed on photographic films during their manufacturing process to assist later digital scanning of still photographic images (see U.S. Pat. No. 6,278,482B1hereinafter referred to as the Sartor patent), fiducial marks have not been used for motion picture film image stabilization including the coincident exposure process 110 described above. The Sartor patent's teaching cannot provide the desired motion picture film image stabilization because it teaches that the fiducial markers are exposed at the film factory during its manufacturing process, while the images are exposed at a different and later time thus only approximately positioned relative to the fiducial marks. In contrast, the method 100 captures the fiducial marks 70 in the motion picture camera 14 during the film holding period (defined hereinafter as coincident) that each associated marked image 72 is captured on the film 10. This allows the relative position between the marked image 72 and the fiducial marks 70 to be extremely accurate. The Strator patent is applicable to still photographic cameras where inter-frame image jitter is irrelevant. Strator patent does not solve inter-frame jitter of motion picture film. The method 100 of the present invention solves the inter-frame jitter of motion picture film by using the coincident exposure process 110 to capture the fiducial marks 70 during the film hold period of the associated marked image 72 and using the fiducial marks 70 via its subsequently converted digital fiducial marks 78 to stabilize the digital images 80 via the digital realignment image process 116 described above.
[0060] As discussed above and referring to
[0061] As discussed above and referring to
[0062] The coincident exposure process 110 to capture each of the marked frames 74 includes exposing an image of external environment onto the exposed film portion 46 of the film 10 using the camera 14 during the film hold period resulting in the marked image 72 contained within the marked frame 74; and exposing the fiducial marking means 66 onto the unexposed film portion 48 of the film 10 using the fiducial system 86 during the same film hold period resulting in the fiducial marks 70 being also contained within the marked frame 74. Accordingly, the coincident exposure process 110 allows the fiducial marks 70 to be associated with the marked image 72 contained within that specific marked frame 74.
[0063] After coincident exposure process 110 has been completed, the method 100 includes the film developing process 112 wherein the film 10 having the marked frames 74 is developed.
[0064] After the film developing process 112 is completed, the method 100 further includes the film digitizing process 114 to digitize each of the marked frames 74 into the digital marked scan 76 wherein the marked image 72 and the fiducial marks 70 contained within each of the marked frames 74 are digitally converted to the digital image 80 and the digital fiducial marks 78 of the digital marked scan 76.
[0065] Once the digitizing process 114 has converted the marked frames 74 into the digital marked scans 76, the method further includes repositioning the digital image 80 of each digital marked scan 76 using dimensional position of the digital fiducial marks 78 shown on each digital marked scan 76. This digital image repositioning process 116 can be completed for each digital marked scan 76 at any time, including but not limited to, immediately after completion of the digitizing process 114 for that specific digital marked scan 76. It is not required to wait until all of the marked frames 74 of the film 10 have been digitized into digital marked scans 76 before starting the digital image repositioning process 116 of a particular digital marked scan 76.
[0066] Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the invention, and other dimensions or geometries are possible. Plural structural components can be provided by a single integrated structure. Alternatively, a single integrated structure might be divided into separate plural components. In addition, while a feature of the present invention may have been described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present invention.