US5874988A
Expired / Lapsed
US
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System and methods for automated color correction
Assignee: Blackmagic Design Pty Ltd
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Filing: 1996-07-08
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Granted: 1999-02-23
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Expires: 2016-07-08
Abstract
Abstract A system and methods for automated color correction. A computer-based workstation is coupled to an image source such as a telecine or other graphic image generating device, an image processing system such as a color corrector, and a utilization device such as a tape recorder or digital storage device. A target image from the image source is displayed on a display monitor associated with the workstation. An image and data storage device stores images and prestored reference image information for a plurality of selectable reference images. A capture device captures a source image from the image source. An image analyzer software process computes statistical parameters of the source image and compares these statistical parameters to prestored statistical parameters of a selected one of the reference images. The statistical parameters include a color distribution or frequency histogram for various color parameters, e.g. gain, gamma, and black level for video signals. A control unit provides correction value outputs to the image source or to the image processing system, to control the color parameters. The correction value outputs are utilized to control image parameters of the source image in an iterative manner until there is a match between prestored statistical parameters of the reference image and the determined statistical parameters of the target image.
Inventors
- 👤 Xueming Henry Gu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:29
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/64; H04N9/74
Claims Analysis
Total Claims: 61
Claim 1
Independent Claim
132 words
A method for automatically processing color image signals, comprising the computer-implemented steps of: storing predetermined color parameter statistical data for a plurality of selectable reference images in a reference image memory device; receiving an operator selection of a particular one of the selectable reference images; retrieving the predetermined color parameter statistical data associated with the selected reference image from the reference image memory device; receiving signals associated with a source image from an image source; capturing the source image signals with a capture device in a source image memory device; determining color parameter statistical data associated with the captured source image; and modifying the source image signals to provide corrected source image signals that have color parameter statistical data that match the predetermined color parameter statistical data of the selected reference image.
Claim 2
Independent Claim
132 words
A method for automatically processing color image signals, comprising the computer-implemented steps of: storing predetermined color parameter statistical data for a plurality of selectable reference images in a reference image memory device; receiving an operator selection of a particular one of the selectable reference images; retrieving the predetermined color parameter statistical data associated with the selected reference image from the reference image memory device; receiving signals associated with a source image from an image source; capturing the source image signals with a capture device in a source image memory device; determining color parameter statistical data associated with the captured source image; and modifying the source image signals to provide corrected source image signals that have color parameter statistical data that match the predetermined color parameter statistical data of the selected reference image.
Claim 3
Dependent Claim
76 words
The method of claim 1, wherein the step of modifying comprises: comparing the predetermined color parameter statistical data of the selected reference image with the determined color parameter statistical data of the source image; and in response to the comparison step indicating a difference between the predetermined color parameter statistical data of the selected reference image and the determined color parameter statistical data of the source image, providing a control signal output to a utilization device.
Claim 4
Dependent Claim
14 words
The method of claim 1, wherein the color image signals are color video signals.
Claim 5
Dependent Claim
39 words
The method of claim 1, wherein the source image is provided by equipment selected from the group: a telecine, a television camera, video tape playback equipment, video signal digitizer, a digital video signal providing device, a graphics generating device.
Claim 6
Dependent Claim
27 words
The method of claim 1, wherein the predetermined color parameter statistical data comprises the highest value, the lowest value, and the peak value of an image signal.
Claim 7
Dependent Claim
24 words
The method of claim 5, wherein the predetermined color parameter statistical data is stored for each of the red, green, and blue video channels.
Claim 8
Dependent Claim
22 words
The method of claim 5, wherein the predetermined color parameter statistical data is stored for the parameters of hue, saturation, and luminance.
Claim 9
Dependent Claim
42 words
The method of claim 1, wherein the step of determining color parameter statistical data associated with the captured source image comprises determining the highest value, the lowest value, and the peak value of the color parameter having the greatest number of occurrences.
Claim 10
Dependent Claim
34 words
The method of claim 1, further comprising the step of displaying a histogram associated with the captured source image after the step of determining color parameter statistical data associated with the captured source image.
Claim 11
Dependent Claim
27 words
The method of claim 9, further comprising the step of displaying data corresponding to the determined statistical parameter of the source image on a workstation display monitor.
Claim 12
Dependent Claim
21 words
The method of claim 1, wherein the method is carried out in a computer based workstation including a workstation display monitor.
Claim 13
Dependent Claim
28 words
The method of claim 11, further comprising the step of displaying, on the workstation display monitor, a plurality of selectable icons representing the plurality of selectable reference images.
Claim 14
Dependent Claim
41 words
The method of claim 12, wherein the step of receiving an operator selection of a particular one of the selectable reference images comprises indication by the operator on a particular one of the plurality of selectable icons with an input device.
Claim 15
Dependent Claim
30 words
The method of claim 1, wherein the utilization device is selected from the group: an image processing system, a color corrector, a parameter controllable image source, an image destination device.
Claim 16
Dependent Claim
119 words
The method of claim 2, further comprising the steps of: utilizing the control signal output at the utilization device to adjust a color parameter; repeating the steps of receiving signals, capturing the source image, determining the color parameter statistical data associated with the captured source image, comparing the predetermined color parameter statistical data associated with the selected reference image with the determined color parameter statistical data of the source image, and providing the control signal output until the difference between the predetermined color parameter statistical data of the selected reference image and the determined color parameter statistical data of the source image is less than a predetermined amount, whereby the signals associated with the source image are automatically adjusted.
Claim 17
Independent Claim
327 words
A method for automatically processing image signals, comprising the computer-implemented steps of: storing predetermined color parameter statistical data for a plurality of selectable reference images in a reference image memory device; receiving signals associated with a source image from an image source; capturing the source image signals with a capture device; digitizing the captured source image signals; storing the digitized captured source image signals in a source image memory device; determining color parameter statistical data associated with the source image; displaying data corresponding to the determined statistical parameter of the source image; displaying a plurality of selectable icons representing the plurality of selectable reference images; receiving an operator selection of one of the selectable reference images by indication on a particular one of the plurality of selectable icons with an input device; retrieving the predetermined color parameter statistical data associated with the selected reference image from the reference image memory device; comparing the predetermined color parameter statistical data of the selected reference image with the determined color parameter statistical data of the source image; in response to the comparison step indicating a difference between the predetermined color parameter statistical data of the selected reference image and the determined color parameter statistical data of the source image, providing a control signal output to a utilization device; utilizing the control signal output at the utilization device to adjust a parameter at the image source; repeating the steps of capturing the source image, determining the color parameter statistical data of the source image, comparing the predetermined color parameter statistical data associated with the selected reference image with the determined color parameter statistical data of the source image, and providing a control signal output until the difference between the predetermined color parameter statistical data of the selected reference image and the determined color parameter statistical data of the source image is less than a predetermined amount, whereby the signals associated with the source image are automatically adjusted at the image source.
Claim 18
Independent Claim
327 words
A method for automatically processing image signals, comprising the computer-implemented steps of: storing predetermined color parameter statistical data for a plurality of selectable reference images in a reference image memory device; receiving signals associated with a source image from an image source; capturing the source image signals with a capture device; digitizing the captured source image signals; storing the digitized captured source image signals in a source image memory device; determining color parameter statistical data associated with the source image; displaying data corresponding to the determined statistical parameter of the source image; displaying a plurality of selectable icons representing the plurality of selectable reference images; receiving an operator selection of one of the selectable reference images by indication on a particular one of the plurality of selectable icons with an input device; retrieving the predetermined color parameter statistical data associated with the selected reference image from the reference image memory device; comparing the predetermined color parameter statistical data of the selected reference image with the determined color parameter statistical data of the source image; in response to the comparison step indicating a difference between the predetermined color parameter statistical data of the selected reference image and the determined color parameter statistical data of the source image, providing a control signal output to a utilization device; utilizing the control signal output at the utilization device to adjust a parameter at the image source; repeating the steps of capturing the source image, determining the color parameter statistical data of the source image, comparing the predetermined color parameter statistical data associated with the selected reference image with the determined color parameter statistical data of the source image, and providing a control signal output until the difference between the predetermined color parameter statistical data of the selected reference image and the determined color parameter statistical data of the source image is less than a predetermined amount, whereby the signals associated with the source image are automatically adjusted at the image source.
Claim 19
Dependent Claim
203 words
In a color correction system including an image source, an image processing system coupled to the image source for imparting color corrections to signals provided by the image source, and a computer based workstation for controlling the image processing system, a method for automated color correction, comprising the steps of: storing predetermined color parameter statistical data for a plurality of selectable reference images in a reference image memory device; receiving an operator selection of a particular one of the selectable reference images; retrieving the predetermined color parameter statistical data associated with the selected reference image from the reference image memory device; receiving signals associated with a source image from the image source; capturing the source image signals with a capture device in a source image memory device; determining color parameter statistical data associated with the captured source image; comparing the predetermined color parameter statistical data of the selected reference image with the determined color parameter statistical data of the source image; in response to the comparison step indicating a difference between the predetermined color parameter statistical data of the selected reference image and the determined color parameter statistical data of the source image, providing a control signal output to the image processing system.
Claim 20
Dependent Claim
203 words
In a color correction system including an image source, an image processing system coupled to the image source for imparting color corrections to signals provided by the image source, and a computer based workstation for controlling the image processing system, a method for automated color correction, comprising the steps of: storing predetermined color parameter statistical data for a plurality of selectable reference images in a reference image memory device; receiving an operator selection of a particular one of the selectable reference images; retrieving the predetermined color parameter statistical data associated with the selected reference image from the reference image memory device; receiving signals associated with a source image from the image source; capturing the source image signals with a capture device in a source image memory device; determining color parameter statistical data associated with the captured source image; comparing the predetermined color parameter statistical data of the selected reference image with the determined color parameter statistical data of the source image; in response to the comparison step indicating a difference between the predetermined color parameter statistical data of the selected reference image and the determined color parameter statistical data of the source image, providing a control signal output to the image processing system.
Claim 21
Dependent Claim
40 words
The method of claim 17, wherein the source image is provided by equipment selected from the group: a telecine, a television camera, video tape playback equipment, video signal digitizer, a digital video signal providing device, a graphic image gererating device.
Claim 22
Dependent Claim
27 words
The method of claim 17, wherein the predetermined color parameter statistical data comprises the highest value, the lowest value, and the peak value of an image signal.
Claim 23
Dependent Claim
24 words
The method of claim 19, wherein the predetermined color parameter statistical data is stored for each of the red, green, and blue video channels.
Claim 24
Dependent Claim
22 words
The method of claim 19, wherein the predetermined color parameter statistical data is stored for the parameters of hue, saturation, and luminance.
Claim 25
Dependent Claim
42 words
The method of claim 17, wherein the step of determining color parameter statistical data associated with the captured source image comprises determining the highest value, the lowest value, and the peak value of the color parameter having the greatest number of occurrences.
Claim 26
Dependent Claim
34 words
The method of claim 17, further comprising the step of displaying a histogram associated with the captured source image after the step of determining color parameter statistical data associated with the captured source image.
Claim 27
Dependent Claim
27 words
The method of claim 23, further comprising the step of displaying data corresponding to the determined statistical parameter of the source image on a workstation display monitor.
Claim 28
Dependent Claim
23 words
The method of claim 17, further comprising the step of displaying a plurality of selectable icons representing the plurality of selectable reference images.
Claim 29
Dependent Claim
41 words
The method of claim 25, wherein the step of receiving an operator selection of a particular one of the selectable reference images comprises indication by the operator on a particular one of the plurality of selectable icons with an input device.
Claim 30
Dependent Claim
125 words
The method of claim 17, further comprising the steps of: utilizing the control signal output at the image processing system to adjust a color parameter; repeating the steps of receiving signals, capturing the source image, determining the video parameter statistical data associated with the captured source image, comparing the predetermined color parameter statistical data associated with the selected reference image with the determined color parameter statistical data of the source image, and providing the control signal output until the difference between the predetermined color parameter statistical data of the selected reference image and the determined color parameter statistical data of the source image is less than a predetermined amount, whereby the signals associated with the source image are automatically adjusted by the image processing system.
Claim 31
Independent Claim
257 words
A system for the automated correction of image signals, comprising: a computer based workstation including a memory, a workstation display monitor, a data input port, a data output port, and an operator input device; an image source device for providing image signals; an image processing system for imparting color corrections to an input signal received from said image source device and providing a color corrected output signal; a utilization device coupled to said image processing system; the workstation being operative to: store predetermined color parameter statistical data for a plurality of selectable reference images in the memory; display a window on the display monitor including a plurality of selectable icons associated with the plurality of selectable reference images; receive an operator selection of a particular one of the selectable reference images with the operator input device; retrieve the predetermined color parameter statistical data associated with the selected reference image from the memory; receive signals associated with a source image from the image source device at the data input port; capture the source image signals in the memory; determine color parameter statistical data associated with the captured source image; compare the predetermined color parameter statistical data of the selected reference image with the determined color parameter statistical data of the source image; in response to the comparison step indicating a difference between the predetermined color parameter statistical data of the selected reference image and the determined color parameter statistical data of the source image, provide a control signal output to the utilization device on the data output port.
Claim 32
Independent Claim
257 words
A system for the automated correction of image signals, comprising: a computer based workstation including a memory, a workstation display monitor, a data input port, a data output port, and an operator input device; an image source device for providing image signals; an image processing system for imparting color corrections to an input signal received from said image source device and providing a color corrected output signal; a utilization device coupled to said image processing system; the workstation being operative to: store predetermined color parameter statistical data for a plurality of selectable reference images in the memory; display a window on the display monitor including a plurality of selectable icons associated with the plurality of selectable reference images; receive an operator selection of a particular one of the selectable reference images with the operator input device; retrieve the predetermined color parameter statistical data associated with the selected reference image from the memory; receive signals associated with a source image from the image source device at the data input port; capture the source image signals in the memory; determine color parameter statistical data associated with the captured source image; compare the predetermined color parameter statistical data of the selected reference image with the determined color parameter statistical data of the source image; in response to the comparison step indicating a difference between the predetermined color parameter statistical data of the selected reference image and the determined color parameter statistical data of the source image, provide a control signal output to the utilization device on the data output port.
Claim 33
Dependent Claim
29 words
The system of claim 28, wherein each of the selectable icons comprises a visual scene representation (VSR) of an image for which predetermined video parameter statistical data is available.
Claim 34
Dependent Claim
65 words
The system of claim 28, wherein the workstation is operative to obtain a visual scene representation (VSR) of a source image provided by the source image device, and further operative, during the determination of color parameter statistical data associated with the captured source image, to display a window on the display monitor including said VSR and a histogram corresponding to the color parameter statistical data.
Claim 35
Dependent Claim
21 words
The system of claim 28, wherein the workstation is further operative to display selection controls for a selectable color control parameter.
Claim 36
Dependent Claim
19 words
The system of claim 31, wherein the selectable color control parameter is selected from the group: gain, gamma, black.
Claim 37
Dependent Claim
28 words
The system of claim 28, further comprising a signal switching device for switching the workstation data input port between the image source device and the image processing system.
Claim 38
Dependent Claim
14 words
The system of claim 28, further comprising a target image display for displaying images.
Claim 39
Dependent Claim
15 words
The system of claim 34, wherein the target image display is a second display monitor.
Claim 40
Dependent Claim
45 words
The system of claim 34, wherein the workstation is further operative to display a spot size control for controlling selection of a predetermined region on the target image display; and utilize the predetermined region on the target image display to determine the source image signals.
Claim 41
Dependent Claim
40 words
The system of claim 36, wherein the size and location of the predetermined region are dynamically adjustable during the step of obtaining a reference image as well as during the workstation operations for comparing and providing a control signal output.
Claim 42
Dependent Claim
174 words
The system of claim 34, wherein the workstation is further operative to: display a first control screen on the workstation display monitor comprising a plurality of selectable visual scene representation (VSR) icons, each selectable VSR icon representing one of a plurality of selectable reference images for which predetermined color parameter statistical data is available; in response to first user command, display a second control screen on the workstation display monitor including a visual scene representation (VSR) region; in response to a second user command, capture a visual scene representation of the image displayed on the target image display and displaying the visual scene representation in the VSR region of the second control screen; in response to a third user command, determine color parameter statistical data associated with the image represented by the captured VSR; store the captured VSR and its associated color parameter statistical data in said memory as said predetermined color parameter statistical data; and display the captured VSR on said first control screen as one of the plurality of selectable VSR icons.
Claim 43
Independent Claim
227 words
A method for the automated correction of color image signal parameters, the method being carried out on a computer based workstation coupled to an image source that provides source image signals, comprising the steps of: displaying a first control screen on a display monitor comprising a plurality of selectable icons, each selectable icon representing one of a plurality of selectable reference images; storing color parameter statistical data associated with each of the selectable reference images; displaying a match control on the first control screen; and in response to operator actuation of the match control, capturing the source image signals with a capture device in a source image memory device, determining color parameter statistical data associated with the captured source image, comparing the predetermined color parameter statistical data of the selected reference image with the determined color parameter statistical data of the source image, in response to the comparison step indicating a difference between the predetermined color parameter statistical data of the reference image and the determined color parameter statistical data of the source image, providing a control signal output to a utilization device, utilizing the control signal output at the utilization device to control a color parameter of the image source as the source image signals are provided; and repeating the steps of capturing, determining, comparing, and providing a control signal output until a predetermined terminating event.
Claim 44
Independent Claim
227 words
A method for the automated correction of color image signal parameters, the method being carried out on a computer based workstation coupled to an image source that provides source image signals, comprising the steps of: displaying a first control screen on a display monitor comprising a plurality of selectable icons, each selectable icon representing one of a plurality of selectable reference images; storing color parameter statistical data associated with each of the selectable reference images; displaying a match control on the first control screen; and in response to operator actuation of the match control, capturing the source image signals with a capture device in a source image memory device, determining color parameter statistical data associated with the captured source image, comparing the predetermined color parameter statistical data of the selected reference image with the determined color parameter statistical data of the source image, in response to the comparison step indicating a difference between the predetermined color parameter statistical data of the reference image and the determined color parameter statistical data of the source image, providing a control signal output to a utilization device, utilizing the control signal output at the utilization device to control a color parameter of the image source as the source image signals are provided; and repeating the steps of capturing, determining, comparing, and providing a control signal output until a predetermined terminating event.
Claim 45
Dependent Claim
19 words
The method of claim 39, further comprising the step of displaying selection controls for a selectable color control parameter.
Claim 46
Dependent Claim
19 words
The method of claim 40, wherein the selectable color control parameter is selected from the group: gain, gamma, black.
Claim 47
Dependent Claim
60 words
The method of claim 39, further comprising the step of displaying the image produced by the image source on a target image display for viewing by an operator; displaying a spot size control for controlling selection of a predetermined region on the target image display; utilizing the predetermined region on the target image display to determine the source image signals.
Claim 48
Dependent Claim
30 words
The method of claim 39, wherein the terminating event comprises completion of a predetermined number of iterations of the steps of capturing, determining, comparing, and providing a control signal output.
Claim 49
Dependent Claim
42 words
The method of claim 39, wherein the terminating event comprises determination that the difference between the predetermined color parameter statistical data of the reference image and the determined color parameter statistical data of the source image is less than a predetermined amount.
Claim 50
Dependent Claim
31 words
The method of claim 39, further comprising the step of utilizing the control signal output to control a color parameter of the image source as the source image signals are provided.
Claim 51
Dependent Claim
27 words
The method of claim 39, further comprising the step of utilizing the control signal output at color correction equipment to control a parameter of the source image.
Claim 52
Dependent Claim
19 words
The method of claim 39, further comprising the step of displaying the source image on a target image display.
Claim 53
Dependent Claim
47 words
The method of claim 47, wherein the workstation includes means for selecting between signals provided by the image source and signals provided by the color correction equipment, and further comprising the step of selecting the image source or the color correction equipment to display signals being corrected.
Claim 54
Dependent Claim
42 words
The method of claim 39, wherein the workstation is coupled to an image processing system operative to impart color corrections to input signals provided by the image source, and wherein the workstation includes color correction software for controlling the image processing system.
Claim 55
Dependent Claim
223 words
In a video signal color correction system, a method for capturing reference information associated with an image produced by an image source, comprising the steps of: displaying an image produced by the image source on a display monitor; displaying a first control screen on the display monitor comprising a plurality of selectable visual scene representation (VSR) icons, each selectable VSR icon representing one of a plurality of selectable reference images for which captured reference information is available; in response to first user command, displaying a second control screen on the display monitor including a visual scene representation (VSR) region; in response to a second user command, capturing a visual scene representation of the image displayed on the display monitor and displaying the visual scene representation in the VSR region of the second control screen; in response to a third user command, determining color parameter statistical data associated with the image represented by the captured VSR; storing the captured VSR and its associated color parameter statistical data in a memory device as said reference information; and displaying the captured VSR on the first control screen as one of the plurality of selectable VSR icons, wherein the image produced by the image source is displayed on a target image display monitor. and the first and second control scenes are displayed on a separate display monitor.
Claim 56
Dependent Claim
223 words
In a video signal color correction system, a method for capturing reference information associated with an image produced by an image source, comprising the steps of: displaying an image produced by the image source on a display monitor; displaying a first control screen on the display monitor comprising a plurality of selectable visual scene representation (VSR) icons, each selectable VSR icon representing one of a plurality of selectable reference images for which captured reference information is available; in response to first user command, displaying a second control screen on the display monitor including a visual scene representation (VSR) region; in response to a second user command, capturing a visual scene representation of the image displayed on the display monitor and displaying the visual scene representation in the VSR region of the second control screen; in response to a third user command, determining color parameter statistical data associated with the image represented by the captured VSR; storing the captured VSR and its associated color parameter statistical data in a memory device as said reference information; and displaying the captured VSR on the first control screen as one of the plurality of selectable VSR icons, wherein the image produced by the image source is displayed on a target image display monitor. and the first and second control scenes are displayed on a separate display monitor.
Claim 57
Dependent Claim
34 words
The method of claim 50, further comprising the step of storing color parameter statistical data associated with each of the selectable reference images in the memory device for use by the color correction equipment.
Claim 58
Dependent Claim
41 words
The method of claim 50, wherein the user commands are provided by an operator input device; the first user command is a set command; the second user command is a capture command; and the third user command is an initialize command.
Claim 59
Dependent Claim
32 words
The method of claim 50, in further response to the third user command, displaying a graphical representation of the color parameter statistical data on a third control screen on the display monitor.
Claim 60
Dependent Claim
220 words
In a video signal color correction system, a method for capturing reference information associated with an image produced by an image source, comprising the steps of: displaying an image produced by the image source on a display monitor; displaying a first control screen on the display monitor comprising a plurality of selectable visual scene representation (VSR) icons, each selectable VSR icon representing one of a plurality of selectable reference images for which captured reference information is available; in response to first user command, displaying a second control screen on the display monitor including a visual scene representation (VSR) region; in response to a second user command, capturing a visual scene representation of the image displayed on the display monitor and displaying the visual scene representation in the VSR region of the second control screen; in response to a third user command, determining color parameter statistical data associated with the image represented by the captured VSR; in further response to the third user command, displaying a graphical representation of the color parameter statistical data on a third control screen on the display monitor; storing the captured VSR and its associated color parameter statistical data in a memory device as said reference information; and displaying the captured VSR on the first control screen as one of the plurality of selectable VSR icons.
Claim 61
Dependent Claim
220 words
In a video signal color correction system, a method for capturing reference information associated with an image produced by an image source, comprising the steps of: displaying an image produced by the image source on a display monitor; displaying a first control screen on the display monitor comprising a plurality of selectable visual scene representation (VSR) icons, each selectable VSR icon representing one of a plurality of selectable reference images for which captured reference information is available; in response to first user command, displaying a second control screen on the display monitor including a visual scene representation (VSR) region; in response to a second user command, capturing a visual scene representation of the image displayed on the display monitor and displaying the visual scene representation in the VSR region of the second control screen; in response to a third user command, determining color parameter statistical data associated with the image represented by the captured VSR; in further response to the third user command, displaying a graphical representation of the color parameter statistical data on a third control screen on the display monitor; storing the captured VSR and its associated color parameter statistical data in a memory device as said reference information; and displaying the captured VSR on the first control screen as one of the plurality of selectable VSR icons.
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