CN103795942B - Smear correction method of frame transfer CCD on basis of virtual reference lines - Google Patents
Smear correction method of frame transfer CCD on basis of virtual reference lines Download PDFInfo
- Publication number
- CN103795942B CN103795942B CN201410032174.6A CN201410032174A CN103795942B CN 103795942 B CN103795942 B CN 103795942B CN 201410032174 A CN201410032174 A CN 201410032174A CN 103795942 B CN103795942 B CN 103795942B
- Authority
- CN
- China
- Prior art keywords
- row
- line
- virtual reference
- clock
- reference lines
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 238000012546 transfer Methods 0.000 title claims abstract description 26
- 238000000034 method Methods 0.000 title claims abstract description 15
- 238000012937 correction Methods 0.000 title claims abstract description 9
- 238000003384 imaging method Methods 0.000 claims description 14
- 235000005035 Panax pseudoginseng ssp. pseudoginseng Nutrition 0.000 claims description 4
- 235000003140 Panax quinquefolius Nutrition 0.000 claims description 4
- 235000008434 ginseng Nutrition 0.000 claims description 4
- 230000003287 optical effect Effects 0.000 claims description 4
- 238000009825 accumulation Methods 0.000 claims description 3
- 230000006399 behavior Effects 0.000 claims description 3
- 238000001514 detection method Methods 0.000 abstract description 2
- 238000000605 extraction Methods 0.000 abstract 1
- 238000003702 image correction Methods 0.000 abstract 1
- 238000009795 derivation Methods 0.000 description 4
- 230000004313 glare Effects 0.000 description 4
- 240000002853 Nelumbo nucifera Species 0.000 description 2
- 235000006508 Nelumbo nucifera Nutrition 0.000 description 2
- 235000006510 Nelumbo pentapetala Nutrition 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Transforming Light Signals Into Electric Signals (AREA)
Abstract
The invention provides a smear correction method of a frame transfer CCD on the basis of virtual reference lines, and belongs to the technical field of photoelectric detection. In a technical route based on a reference line, dark reference lines are replaced by the virtual reference lines so as to solve the problem that the dark reference lines are prone to being polluted by stray light. When an image is read, an ROI reading technology is used so as to increase the number of the reference lines as much as possible to improve the signal to noise ratio of Smear signals; when the virtual reference lines are read, a multi-line in-chip combining technology is used so as to improve the signal to noise ratio for the largest possible, and meanwhile only one line of data need to be stored and processed additionally in the method. The method includes the specific steps of (1) frame transfer, wherein a first line which needs to be read out is transferred to the bottom end of a storage area, (2), register emptying and horizontal reading, (3) ROI image reading, (4) dumping of image lines and dark reference lines, wherein the image lines and dark reference lines do not need to be read, (5) register emptying and horizontal reading, (6) reading of the virtual reference lines after multi-line combining, (7) dark signal correction and (8) smear signal extraction and image correction.
Description
Technical field
The invention belongs to technical field of photoelectric detection, and in particular to a kind of Smear bearing calibrations of frame transfer CCD.
Background technology
The generation of Smear phenomenons be due to frame transfer CCD during frame transfer its photosensitive area（It is photosensitive in imaging area
Effective coverage, remainder are secretly to refer to pixel）Interior pixel is still caused photosensitive, and it is the intrinsic spy of frame transfer CCD
Property, it is particularly evident in the case of high light short exposure time.Increase mechanical shutter and can avoid Smear phenomenons, but this is clearly
A kind of retroversion that CCD is shifted to full frame；The frequency for improving frame transfer clock can weaken Smear phenomenons, but can not disappear completely
Remove.
Correcting algorithm common at present has three kinds：The first is the position for going out Smear generations based on the statistical estimate to full figure
Put and size, other images are then difficult to be suitable for just for the certain types of image such as star chart effectively；Second is to be based on
Smear produces the full frame derivation algorithm of principle, the mathematical procedure that it is produced according to Smear phenomenons, is multiplied by after all rows are added
Scale factor obtains Smear signals（CCD is without electronic shutter）, or start to be solved according to scale factor line by line from the 1st row
Ideal image after Smear corrections（CCD has electronic shutter）.Smear signals accuracy that this algorithm is obtained and signal to noise ratio are all
It is very high, but the generation efficiency of time of exposure, the cycle of frame transfer clock and Smear electric charges is known in its requirement, and can not have
Pixel saturation, necessary whole frame all read；The third is the correcting algorithm based on dark reference line, and it directly make use of dark reference line
It is not photosensitive during exposing, this feature with photosensitive area pixel identical Smear signal has but been experienced in the process of frame transfer,
Simply Smear signals just can be directly solved after dark signal correction.The algorithm is simple and practical, it is not necessary to which full frame reads,
But as the number of dark reference line is generally all little, the Smear signal noises for solving are very big, and if the light in CCD image planes
Close from dark reference line according to region, that actually these dark reference line can all be subject to the pollution of veiling glare and have certain light exposure,
Calculated Smear signals are just no longer accurate, as shown in top curve in Fig. 2.
The content of the invention
Present invention solves the technical problem that being to overcome the shortcomings of existing algorithm, provided by the particular design of driver' s timing
A kind of Smear bearing calibrations based on virtual reference row.
The technical scheme of solve problem of the present invention：
Smear bearing calibrations of the frame transfer CCD based on virtual reference row, define virtual reference behavior dark reference line it
Afterwards, beyond CCD device, CCD is just transitioned into after virtual presence, end exposure during frame transfer line by line during exposing and opened
The reference line that beginning is truly present；If there is N imaging areaIThe photosensitive pixel of row, NDRow secretly refers to pixel, and there is N memory blockS=NI+NRRow picture
Unit；N of the ROI region from imaging areaY1OK（1≤NY1≤NI）Start, then be up to NR-ND+(NY1- 1) individual virtual reference row；House
Last three row is abandoned, N is takenV=NR-ND+(NY1- 1) -3 virtual reference rows；Comprise the following steps that：
The electric charge that imaging area exposes accumulation is rapidly transferred to memory block by step one, control frame shifted clock signal, is turned
The number of cycles for moving clock is NS+NY1-1；Simultaneously by be constantly transferred to during frame transfer horizontal readout register without electricity consumption
Lotus reads reset and falls or be poured off；
Step 2, controls horizontal readout register and continuously reads more than two rows, and period reads reseting pulse signal and remains
The high level state of reset, thoroughly to remove the unwanted charge that may be remained in horizontal readout register；
Step 3, controls row transfering clock, horizontal readout clock and reads reseting pulse signal by the pixel in ROI regionOne by one read line by line；
Step 4, control row transfering clock, horizontal readout clock and electric charge topple over grid control signal by ROI and virtual ginseng
The unwanted charge examined between row is all poured off；
Step 5, execution step two remove horizontal readout register；
Step 6, control row transfering clock is continuously by NVIndividual virtual reference row is transferred to horizontal readout register, realizes
Merge in multirow piece, then control horizontal readout clock and read reseting pulse signal read one by one pixel it is virtual after merging
Reference line
Step 7, the image and virtual reference row to reading do dark signal correction；
Step 8, by virtual reference row divided by NV, obtain the Smear signals after " multiple repairing weld-average " method noise reductionThe optical signal image I after it can be corrected is deducted from image line by line finallyi,j。
The positive effect of the present invention：
1st, the present invention have selected technology path based on reference line, it is to avoid in background technology, full frame derivation algorithm will be demanded perfection
The problems such as frame reads, cannot process saturation image, while having used for reference because the line number of its participation solution is more so the Smear letters for solving
Number little advantage of noise, employs ROI sensing techniques in method, to increase the number of reference line as much as possible, exponentially carries
The signal to noise ratio of the high Smear signals for solving.
2nd, the concept of " virtual reference row " is proposed, the correcting algorithm based on dark reference line is solved and is easily made by veiling glare pollution
The problems such as declining, cause Smear signal noises big less with reference to line number into accuracy.
3rd, when virtual reference row is read, folding is employed in pixel piece to improve signal to noise ratio most possibly, together
When also to cause this method to need extra storage and processing data amount be only a line.
Description of the drawings
Fig. 1 is the frame transfer CCD pixel layouts with virtual reference row.
Fig. 2 is dark reference line, virtual reference row and the Smear signal drawn with full frame derivation algorithm after black level offset compensation
One comparative result.The dark reference line of 1025th～1027 behavior, the 1028th row start as virtual reference row.Can see, even if
It is, from the 3rd farthest dark reference line of photosensitive area, and have considerable light exposure, cannot be used at all calculating Smear
Signal.And the signal of virtual reference row and the Smear signals drawn with full frame derivation algorithm have goodish concordance.
Specific embodiment
Below by embodiment, the invention will be further described.
As shown in figure 1, virtual reference row is after dark reference line, beyond CCD device, the virtual presence during exposing
Reference line.These virtual reference rows just transition into CCD after end exposure line by line and start truly to deposit during frame transfer
Subsequently as dark reference line, experiencing and accumulating and imaging area pixel identical Smear signal.As they are in exposure period
Between be virtual presence, time of exposure is zero in other words, thus by veiling glare pollution problem.And as available virtual is joined
The increase of row number is examined, the signal to noise ratio of the Smear signals for extracting exponentially can be improved.
The technical scheme of solve problem of the present invention is as follows：
In frame transfer by ROI in imaging area（RegionOfInterest, middle finger of the present invention reading region interested）
The first row in region is transferred to the lowermost end of memory block, then line by line read ROI region in image, be poured off ROI with it is virtual
Useless row between reference line, finally reads virtual reference row, and now multirow only reads a phase by the way of merging in the piece
Plus row, to improve signal to noise ratio and reduce data volume.
As shown in figure 1, setting imaging area has NIThe photosensitive pixel of row, NDRow secretly refers to pixel, and there is N memory blockS=NI+NRRow pixel.
N of the ROI region from imaging areaY1OK（1≤NY1≤NI）Start, then can have up to NR-ND+(NY1- 1) individual virtual reference row.
It is possible to be polluted by veiling glare in view of last rows when reading near imaging area, gives up last 3 row, finally have NV=NR-ND+
(NY1- 1) -3 virtual reference rows can use.
Concrete steps are described as follows：
The electric charge that imaging area exposes accumulation is rapidly transferred to memory block by step one, control frame shifted clock signal, is turned
The number of cycles for moving clock is NS+NY1-1；Simultaneously by be constantly transferred to during frame transfer horizontal readout register without electricity consumption
Lotus reads reset and falls or be poured off；
Step 2, controls horizontal readout register and continuously reads more than 2 rows, and period reads reseting pulse signal and remains again
The high level state of position, thoroughly to remove the unwanted charge that may be remained in horizontal readout register；
Step 3, controls row transfering clock, horizontal readout clock and reads reseting pulse signal by the pixel in ROI regionOne by one read line by line；
Step 4, control row transfering clock, horizontal readout clock and electric charge topple over grid control signal by ROI and virtual ginseng
The unwanted charge examined between row is all poured off；
2. step 5, execution step remove horizontal readout register；
Step 6, control row transfering clock is continuously by NVIndividual virtual reference row is transferred to horizontal readout register, realizes
Merge in multirow piece, then control horizontal readout clock and read reseting pulse signal read one by one pixel it is virtual after merging
Reference line
Step 7, the image and virtual reference row to reading do dark signal correction；
Step 8, by virtual reference row divided by NV, obtain the Smear signals after " multiple repairing weld-average " method noise reductionThe optical signal image I after it can be corrected is deducted from image line by line finallyi,j。
Embodiment：
The frame transfer CCD47-20 of e2v companies, effective pixel 1024 × 1024, i.e. NI=1024, ND=3 dark reference lines, deposit
Storage area has NS=1024+9 rows, i.e. NRIt is the 50th～974 row, i.e. N that=9, ROI read regionY1=50, finally there is NV=9-3+(50-1)-
3=52 virtual reference row can use.
CCD47-20 realizes that the reading control sequential with virtual reference row is as follows：
1. control frame shifted clock signalWithImaging area exposure is accumulated
Tired electric charge is rapidly transferred to memory block, and the number of cycles of transfering clock is NS+NY1-1=1033+50-1=1082；Same time control
The flat readout clock of controlling the water circulationWithState is read for continuous, reseting pulse signal is readRemain reset
High level state, the unwanted charge that frame transfer process is constantly transferred to horizontal readout register is fallen with " read-reset ", or
Electric charge is toppled over into gate clock DG and is set to height, unwanted charge is poured off；
2. control horizontal readout clockWithState is read for continuous, reseting pulse signal is readThe high level state of reset is remained, it is continuous to read more than 2 rows, may be remained with thoroughly removing in horizontal readout register
Unwanted charge；
3. control row shifted clock signalWithA line pixel electric charge transfer to level is read and is posted
Storage, then control horizontal readout clockWith reading reseting pulse signalBy pixel electric charge one by one
Read；
4. circulate execution step and 3. read 974-50+1=925 row view data altogether；
5. control row transfering clockHorizontal readout clockRead
Go out reseting pulse signalGate clock DG being toppled over electric charge, the 975th～1027 row is amounted to into the electric charge that 53 rows need not read
Horizontal readout register is transferred to line by line from memory block and rapid dumps fall；
6. 2. execution step removes horizontal readout register；
7. control row shifted clock signalWithContinuously 52 row virtual reference pixel electric charge transfers are arrived
Horizontal readout register, completes to merge in the piece of virtual reference row；
8. 3. execution step reads the virtual reference row after merging；
9. the image and virtual reference row to reading does dark signal correction；
10. virtual reference row is obtained into the Smear signals after " multiple repairing weld-average " method noise reduction, finally from figure divided by 52
The optical signal image after it can be corrected is deducted line by line as in.
Claims (1)
1. Smear bearing calibrations of the frame transfer CCD based on virtual reference row, is characterized in that, defines virtual reference behavior and is secretly joining
After examining row, beyond CCD device, just it is transferred into line by line during frame transfer after virtual presence, end exposure during exposing
Enter the reference line that CCD starts truly to exist；If there is N imaging areaIThe photosensitive pixel of row, NDRow secretly refers to pixel, and there is N memory blockS=
NI+NRRow pixel；N of the ROI region from imaging areaY1Row starts, 1≤NY1≤NI, then be up to NR-ND+(NY1- 1) individual virtual ginseng
Examine row；Give up last three row, take NV=NR-ND+(NY1- 1) -3 virtual reference rows；Comprise the following steps that：
The electric charge that imaging area exposes accumulation is rapidly transferred to memory block by step one, control frame shifted clock signal, during transfer
The number of cycles of clock is NS+NY1-1；Simultaneously the unwanted charge that horizontal readout register is constantly transferred to during frame transfer is read
Go out reset to fall or be poured off；
Step 2, controls horizontal readout register and continuously reads more than two rows, and period reads reseting pulse signal and remains reset
High level state, with thoroughly remove in horizontal readout register may residual unwanted charge；
Step 3, controls row transfering clock, horizontal readout clock and reads reseting pulse signal by the pixel in ROI regionBy
Row one by one reads；
Step 4, control row transfering clock, horizontal readout clock and electric charge topple over grid control signal by ROI region and virtual ginseng
The unwanted charge examined between row is all poured off；
Step 5, execution step two remove horizontal readout register；
Step 6, control row transfering clock is continuously by NVIndividual virtual reference row is transferred to horizontal readout register, realizes multirow piece
Interior merging, then controls horizontal readout clock and reads reseting pulse signal to read the virtual reference row after merging one by one pixel
Step 7, the image and virtual reference row to reading do dark signal correction；
Step 8, by virtual reference row divided by NV, obtain the Smear signals after " multiple repairing weld-average " method noise reduction
The optical signal image I after it can be corrected is deducted from image line by line finallyi,j。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410032174.6A CN103795942B (en) | 2014-01-23 | 2014-01-23 | Smear correction method of frame transfer CCD on basis of virtual reference lines |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410032174.6A CN103795942B (en) | 2014-01-23 | 2014-01-23 | Smear correction method of frame transfer CCD on basis of virtual reference lines |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103795942A CN103795942A (en) | 2014-05-14 |
| CN103795942B true CN103795942B (en) | 2017-04-12 |
Family
ID=50671180
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410032174.6A Expired - Fee Related CN103795942B (en) | 2014-01-23 | 2014-01-23 | Smear correction method of frame transfer CCD on basis of virtual reference lines |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103795942B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110375785A (en) * | 2019-06-14 | 2019-10-25 | 中国科学院西安光学精密机械研究所 | A kind of response accumulated error bearing calibration of high frame frequency large area array frame transfer detector |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104486563B (en) * | 2014-12-19 | 2017-10-31 | 中国科学院长春光学精密机械与物理研究所 | The electrically charged frame transfer CCD time for exposure for toppling over function is as short as zero implementation method |
| CN104486556B (en) * | 2014-12-19 | 2018-01-05 | 中国科学院长春光学精密机械与物理研究所 | A kind of implementation method of frame transfer CCD electronic shutters |
| CN104949677A (en) * | 2015-05-20 | 2015-09-30 | 苏州科技学院 | Real-time orbit determination method for drift scanning geosynchronous satellite |
| CN105611197B (en) * | 2015-12-23 | 2018-08-17 | 中国科学院长春光学精密机械与物理研究所 | The anti-saturation reading method of nonreactive overflow-resisting function frame transfer CCD |
| CN106601767B (en) * | 2016-12-02 | 2019-06-04 | 中国电子科技集团公司第四十四研究所 | The positive of electrode signal delay can be reduced and shine frame transfer CCD |
| CN108111785B (en) * | 2017-12-28 | 2020-05-15 | Oppo广东移动通信有限公司 | Image processing method and device, computer readable storage medium and computer device |
| CN110412060B (en) * | 2019-08-05 | 2021-08-17 | 重庆大学 | Smear correction method for CT scanning full-frame CCD type x-ray detector |
| CN112217959B (en) * | 2020-09-25 | 2022-08-09 | 中国科学院合肥物质科学研究院 | Smear noise elimination method of satellite-borne adjacent CCD detector and storage medium |
| CN112763442A (en) * | 2020-12-25 | 2021-05-07 | 中国科学院合肥物质科学研究院 | Processing method for rapidly reducing inversion error of imaging spectrometer |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005159564A (en) * | 2003-11-21 | 2005-06-16 | Sony Corp | Method for correcting smear of ccd solid state imaging device and electronic apparatus |
| JP2009100283A (en) * | 2007-10-17 | 2009-05-07 | Canon Inc | Imaging apparatus and control method for imaging apparatus |
| CN101715644A (en) * | 2007-06-15 | 2010-05-26 | 普廷数码影像控股公司 | Imagers with high speed digital frame transfer and frame processing |
| CN101853501A (en) * | 2010-05-13 | 2010-10-06 | 西北工业大学 | Smear effect processing method of CCD (Charge-Coupled Device) sensor |
| CN102081793A (en) * | 2011-01-06 | 2011-06-01 | 西北工业大学 | Method for eliminating smear effect bright line of starry sky background image frame transfer type CCD sensor |
| US8189077B2 (en) * | 2009-08-10 | 2012-05-29 | Altek Corporation | Method for reducing smear effect of dynamic image |
-
2014
- 2014-01-23 CN CN201410032174.6A patent/CN103795942B/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005159564A (en) * | 2003-11-21 | 2005-06-16 | Sony Corp | Method for correcting smear of ccd solid state imaging device and electronic apparatus |
| CN101715644A (en) * | 2007-06-15 | 2010-05-26 | 普廷数码影像控股公司 | Imagers with high speed digital frame transfer and frame processing |
| JP2009100283A (en) * | 2007-10-17 | 2009-05-07 | Canon Inc | Imaging apparatus and control method for imaging apparatus |
| US8189077B2 (en) * | 2009-08-10 | 2012-05-29 | Altek Corporation | Method for reducing smear effect of dynamic image |
| CN101853501A (en) * | 2010-05-13 | 2010-10-06 | 西北工业大学 | Smear effect processing method of CCD (Charge-Coupled Device) sensor |
| CN102081793A (en) * | 2011-01-06 | 2011-06-01 | 西北工业大学 | Method for eliminating smear effect bright line of starry sky background image frame transfer type CCD sensor |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110375785A (en) * | 2019-06-14 | 2019-10-25 | 中国科学院西安光学精密机械研究所 | A kind of response accumulated error bearing calibration of high frame frequency large area array frame transfer detector |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103795942A (en) | 2014-05-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103795942B (en) | Smear correction method of frame transfer CCD on basis of virtual reference lines | |
| Gu et al. | Coded rolling shutter photography: Flexible space-time sampling | |
| CN105721797B (en) | Method and system for rolling shutter barcode imaging | |
| CN103248840B (en) | Picture pick-up device, X-ray detector and image capture method | |
| CN104486563B (en) | The electrically charged frame transfer CCD time for exposure for toppling over function is as short as zero implementation method | |
| CN107710415B (en) | Interline charge coupled device | |
| JP2013538518A5 (en) | ||
| CN107347142B (en) | For implementing the method and system of H striping removal in the image sensor | |
| CN105794203A (en) | High dynamic-range image sensor | |
| CN108600658B (en) | Exposure time adjusting method for image motion matching of earth observation frame transfer area array CCD | |
| TW200525495A (en) | Graphic image signal processing device | |
| CN106231210A (en) | A kind of radioscopic image sensor and the method eliminating afterimage of image | |
| CN104365084B (en) | Pixel processing circuit | |
| CN102055915B (en) | Driving time sequence implementation method of frame transfer CCD (Charge Coupled Device) short exposure time | |
| CN101569174B (en) | Image quality improving apparatus and image quality improving method | |
| CN106937063A (en) | Method and system for reducing the analog/digital conversion time of dark signal | |
| TW201607319A (en) | Image sensor and sunspot removing method and device thereof | |
| CN102316283A (en) | Real-time light leak phenomenon removing device for space and line space transfer CCD (charge coupled device) camera | |
| CN102497516B (en) | Acceleration method for light measurement of high-resolution charge coupled device (CCD) imaging system | |
| CN105590294A (en) | Image-processing method and electronic equipment | |
| US20110157401A1 (en) | Method for reading out a high dynamic range image and device using the same | |
| CN108495065B (en) | Driving time sequence control method of frame transfer type area array CCD | |
| CN106308834A (en) | X-ray image sensor and method for eliminating ghost image by X-ray image sensor | |
| CN102256047B (en) | Filtering-based 2*2 digital BINNING system | |
| JP5481230B2 (en) | Imaging device and solid-state imaging device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20170412 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |