Image Preservation Through PDFA
纸质阅读 英语作文
Reading on paper has been a tradition for centuries,and it continues to hold a special place in the hearts of many avid readers.Here are some points to consider when discussing the merits of reading from physical books:1.Tactile Experience:Holding a book and flipping through its pages provides a tactile experience that is unique to physical reading.The feel of the paper and the satisfaction of turning a page are elements that many readers find comforting and engaging.2.Focus and Concentration:Studies have shown that reading from a physical book can improve focus and concentration.The absence of digital distractions,such as notifications and the internet,allows readers to immerse themselves in the content without interruptions.3.Eyesight Preservation:Reading from paper is generally easier on the eyes compared to screens.The risk of eye strain and fatigue is reduced,which is particularly beneficial for long reading sessions.4.Aesthetic Pleasure:The design of a book,including its cover,font,and layout, contributes to the overall aesthetic pleasure of reading.Many readers appreciate the artistry involved in book design.5.Ownership and Collection:Owning a physical book gives a sense of possession that digital copies cannot replicate.Building a personal library can be a source of pride and a reflection of ones interests and personality.6.Nostalgia and Tradition:For many,reading a physical book is a nostalgic experience that connects them to a longstanding tradition of reading.It can evoke memories of childhood and a simpler time.7.Annotation and NoteTaking:Writing notes and underlining passages in a physical book is often easier and more satisfying than on a digital device.It also allows for a more personal interaction with the text.8.No Need for Power Source:Unlike ereaders and tablets,physical books do not requirea power source.This makes them convenient for reading in any environment,without the worry of battery life.9.Smell of Books:The scent of a new or old book is a sensory experience that many readers find enjoyable.It can evoke a sense of comfort and familiarity.10.GiftGiving:Physical books make thoughtful and personal gifts.They can be inscribed and shared in a way that digital copies cannot match.In conclusion,while digital reading offers convenience and portability,the experience of reading from a physical book remains unparalleled for many.The sensory,emotional, and practical benefits of paper reading continue to make it a cherished activity for book lovers around the world.。
显微镜光学配置图说明书
Supplementary MethodsOptical configuration:A diagram of the optical configuration used for the photobleaching experiments is shown insupplemental figure 1 below.Supplemental Figure 1. Diagram of the optical configuration of the side-port for photobleaching.e. he d or the YFP bleaching experiment shown in figure 1, the microscope filter cube used for bleaching rom 0DCSXscanning mirrorsView is from above, and the scanning mirrors are at the rear of a Nikon TE-300 inverted microscop The dichroic mirror near the tube lens is a long-pass extended reflection mirror (650 DCXRU). The light from an argon-ion laser (Coherent Sabre) was coupled into an optical fiber and connected to the side-port at the connector shown at the right side of the figure. To preview the fluorescence and select cells, an in-house developed fiber-optic coupled high-power blue light emitting diode (LED) source (patent pending) was connected in place of the laser coupling fiber. Depending on the experiment a band-pass filter was sometimes included before coupling the LED emission to the fiber. In some experiments an additional dichroic mirror, 440 nm long-pass (440DCLP), was included between t fiber-optic coupler and the divergence-correcting lens to allow the additional coupling of a liquid-fille light guide (Oriel) to permit the use of a xenon arc lamp (Cairn).F contained a 545nm long-pass dichroic (545DCLP) and a 540-600nm band-pass emission filter(HQ570/30). A portion of the YFP emission could be monitored visually while scattered light f the 514.5 nm laser excitation was blocked. For bleaching experiments using laser lines shorter than 514.5, a filter cube containing a 510 long pass dichroic and a 510-560 band-pass emission filter (510DCLP and HQ535/50 respectively) was used. The filter cube for the 2-photon excitationcontained a 700 nm short-pass, UV reflecting, dichroic and a 710 short pass emission filter (70and E710SP respectively).YFP photoconversion revisited: confirmation of the CFP-like speciesMichael T Kirber, Kai Chen & John F Keaney JrIn experiments to check if the fluorescent decay product was visible with arc lamp illumination, a filter experiments to check if bleaching using arc lamp illumination produced the fluorescent decay ht , and en rlabs. ther than observing that the fluorescent decay product of YFP could be excited using a configuration ell culture and plasmid transfection: cube containing a 405-445 band-pass excitation filter, a 455 long-pass, extended reflection dichroic, and a 460-500 nm band-pass emission filter (D425/40X, 455DCXRU, and D480/40M respectively) was used. Infrared light was removed from the arc lamp output using a short wavelength visible and UV reflecting cold mirror (Thorlabs).In product, the fiber coupler was removed from the side port and the output from the liquid-filled lig guide and a collimating lens were coupled directly in place of the fiber-optic coupler. The 440DCLP dichroic was left in place. The filter cube used for bleaching contained, a 460-500nm band passemission filter inserted in reverse direction in the excitation position, a 510 nm long-pass dichroic a 510-560 nm band-pass emission filter ( HQ480/40M, 510DCLP, and HQ535/50M respectively) Bleaching YFP about 50% took 2 hours and when the 440DCLP mirror was removed and the CFP filter cube (D425/40X, 455DCXRU, and D480/40M) selected, the fluorescent decay product was se with the arc lamp illumination. All filters and dichroic mirrors were purchased from ChromaTechnology. Optical fiber, lenses, and optomechanical components were purchased from ThoO appropriate for exciting CFP using single photon (arc lamp) or 2-photon excitation, we did not try to determine the excitation spectrum of this byproduct. Such experiments might well be worthwhile but we are not presently set up to carry them out.Cvitrogen) and transfection with overexpression plasmids was ) was age acquisition and display:COS-7 cells were cultured in DMEM (In carried out using Fugene 6 (Roche) in cells at 70% confluency according to the manufacturer’sinstructions. PTP1B trapping mutant expression vector pcDNA6.2/YFP-PTP1B (D181A/Q262A constructed by using PCR subcloning technique with pcDNA6.2/N-YFP vector (Invitrogen) and pJ3H-PTP1B (D181A/Q262A)(kindly provided by Dr. Zhong-Yin Zhang, Indiana University). Cells were grown on glass cover slides and fixed with 4% paraformaldehyde.Imas designed and built in-house in collaboration with the laboratory of inal irror d between the number of counted photons and the brightness of the display.The 2-photon microscope used w Dr. Peter So at the Massachusetts Institute of Technology. The optical microscope portion of the system was a Nikon TE300 and the objective used was a 100X, 1.3 NA, oil-immersion type. Orig images obtained with 2-photon excitation (800 or 916 nm excitation) were 384x384 pixels with each pixel imaging 130 by 130 nm in the sample, which is beyond the resolution capability of the system. The dwell time at each pixel was 2 ms. Images shown in figure 1 are cropped from the originals and are 280 by 280 pixels. The fluorescence at each channel was measured with photon counting photomultiplier tubes (Hamamatsu R4700P-01 for the green channel and R4700P for the bluechannel). The green channel was separated from the red using an extended reflection dichroic m 565 nm long-pass (565DCXR) and the blue and green channels were separated using a 500nm long-pass extended reflection dichroic mirror (500DCXR). The pass-bands of the filters are given in the body of the text. The number of counts at each location in the sample was stored as a 16 bit unsigne integer. Images were imported into ImageJ as raw data. The colors for images in figure 1a-f were chosen to approximate the actual color of the fluorescence. The scale bars indicate the relationshipColocalization:In quantitatively assessing the degree of colocalization of two distinctly fluorescently labeled (or the different colored images each as a sample of a e or expressed) compounds in a cell, it is useful to treat random process which accurately represents it statistically (ergodicity). The normalized covarianc correlation coefficient between 2 sets of data, which in this case are images E and F which are N i x N j in size and contain elements e ij and f ij respectively, can be written as}Where E{ } denotes the “expected value” and E ¯ is the arithmetic mean of the pixel values in image E nd F ¯ is the mean of image F. This calculation has been applied to quantitatively assess colocalization E ()()ij ij e E f F ρ−−a (Vereb et al .). Because expectation is a linear operator, this expression can be rearranged so that the contribution at each pixel pair to the correlation coefficient is clear.ρ==We can then display an image G* with pixel values g*ij , the sum of all the pixels being the correlationoefficient. c*ij ij ij e f E F N N g −=or simplicity we normalize this so that we display images where the mean of all of the pixels, G ¯, is e correlation coefficient.F thij g =ll of the values can be easily calculated using ImageJ (Wayne Rasband, NIH).this manner we can easily compare different size sets of images and not lose the quantitative ove comparing the degree of colocalization under different experimental conditions some caution is oth ference:atko J, Vamosi G, Ibrahim SM, Magyar E, Varga S, Szollosi J, Jenei A, Gaspar R Jr, AIn information. Areas where the normalized covariance image is positive indicate colocalization ab that predicted by random uniform distributions of the 2 fluorescent species. Additionally, there are generally some regions where the pixels have a negative value. These regions correspond to areas where the colocalization of the 2 labeled compounds is less than would be predicted by a uniform random distribution.In needed. For example the regions for which the computation is performed should be similar under b sets of conditions (i.e. ratio of area of background to area of cell interior).re Vereb G, M Waldmann TA, Damjanovich S. Proc Natl Acad Sci U S A. 2000 May 23;97(11):6013-8.。
摄影定格瞬间的英语作文
Photography,an art form that captures the essence of a moment,has the power to freeze time and immortalize memories.It is a medium that allows us to preserve the fleeting beauty of life in a single frame.From the majestic landscapes to the intimate moments shared among loved ones,photography has the unique ability to encapsulate the world around us in a way that transcends the limitations of our own perception.The art of photography has evolved significantly over the years,from the early days of film to the digital age we find ourselves in today.With the advent of smartphones and advanced camera technology,photography has become more accessible to the masses, allowing anyone with a passion for capturing lifes moments to do so with ease and precision.This democratization of the art form has led to a surge in creativity and innovation,as photographers from all walks of life explore new ways to express themselves through the lens.One of the most compelling aspects of photography is its ability to tell a story.A single image can convey a myriad of emotions and narratives,inviting the viewer to delve into the world captured within the frame.Whether its the joy of a childs laughter,the sorrow of a tear,or the quiet contemplation of a solitary figure,photography has the power to evoke a visceral response from those who view it.Moreover,photography serves as a powerful tool for documentation and historical preservation.It allows us to look back on the past and gain insight into the lives of those who came before us.From wartorn battlefields to the peaceful moments of everyday life, photographs serve as a testament to the resilience and adaptability of the human spirit.In addition to its storytelling capabilities,photography also plays a crucial role in shaping our understanding of the world around us.It can raise awareness about social issues, promote environmental conservation,and inspire change on a global scale.Through the lens of a camera,photographers can bring attention to the plight of endangered species, the beauty of our natural landscapes,and the injustices faced by marginalized communities.The process of creating a photograph is an art in itself.It requires a keen eye for composition,an understanding of light and shadow,and the ability to anticipate the perfect moment.Photographers must be patient,often waiting for hours or even days to capture the ideal scene.This dedication to the craft is what sets apart the truly great photographers from the rest.In conclusion,photography is a multifaceted art form that offers a unique perspective on the world around us.It allows us to freeze time,tell stories,and document history in away that is both personal and universal.As technology continues to advance and the accessibility of photography increases,we can only anticipate the incredible ways in which this art form will continue to evolve and inspire.。
A开头英语单词-精选.pdf
单词词汇（1）Aabsent-minded adj. 心不在焉的absorb vt. 吸收；吸引absorbed adj. 投入的，专注的，全神贯注的absurd adj. 荒唐的，荒诞的，怪诞的academic adj. 学习良好的，学术的acceptable adj. 可接受的acre n. 英亩addition n. 加，增加in addition 另外admit vt&vi 承认adolescent adj. 青春期的n. 青少年adopt vt. 收养，领养advance n. 进步，前进advise vt. 建议，劝告advocate vt. 提倡，倡导afterwards adv. 然后，后来agency n. 服务机构，代理agricultural adj. 农业的agriculture n. 农业ahead adv. 往前，向前Push ahead with 义无反顾地进行，努力推进algebra n. 代数alternative n. 可供选择的办法或事物adj. 可供选择的amusement n. 娱乐，消遣amusement park 游乐场announcement n. 宣告，通告，通知anti-desertification n. 抗沙漠化anxiety n. 忧虑，焦虑，不安anxious adj. 焦急的，焦虑的，渴望的apartment n. 房间，公寓apologize vi. 道歉apparently adv. 明显地，显然地appreciate vt. 赞赏，欣赏，赏识approach vt&vi. 接近，靠近area n. 地区，区域argue vt&vi. 争辩arithmetic n. 算术arrest vt&n. 逮捕，拘捕arrival n. 到达者，到达物，到达，到来as a result 结果assess vt. 评估，评价athletic adj. 适合做运动员的，健壮的，强健的，充满活力的atmosphere n. 大气，空气，气氛，氛围attitude n. 态度，看法awful adj. 可怕的awkward adj. 别扭的，不自然的，笨拙的Bbadminton n. 羽毛球beast n. 兽类，畜生behave vi. 举止，行为表现behaviour n. 行为，举止beneficial adj. 有益的，有利的，有帮助的benefit vt. 有利于，使。
摄影存美好记忆的英语作文
Photography is an art form that allows us to capture and preserve precious moments in our lives.It is a powerful tool that can evoke emotions,tell stories,and transport us back to a specific time and place.Here are some reasons why photography is essential in preserving beautiful memories.1.Capturing Fleeting Moments:Life is full of fleeting moments that are gone as quickly as they come.Photography allows us to freeze these moments in time,providing us with a tangible reminder of these instances.2.Emotional Connection:Photos can evoke strong emotions.A picture of a loved one,a cherished pet,or a memorable event can bring back the feelings associated with that moment,making us laugh,cry,or feel nostalgic.3.Documenting Lifes Journey:As we grow and change,photographs serve as a visual diary of our lives.They document our physical changes,the places weve been,and the experiences weve had.4.Preserving Family History:Family photos are a treasure trove of information for future generations.They provide a visual record of our ancestors,their lifestyles,and the times they lived in.5.Artistic Expression:Photography is a form of creative expression.It allows photographers to capture the world from their unique perspective,sharing their vision with others through their images.6.Cultural Preservation:Photography plays a crucial role in documenting and preserving cultural heritage.It helps in recording traditions,architecture,and art forms that might otherwise be lost over time.cational Tool:Photos can be used as educational tools to teach history,science, and art.They provide a visual context that can make learning more engaging and memorable.8.Social Connection:Sharing photos on social media has become a way for people to connect with others,share experiences,and build relationships.Its a modern form of communication that bridges distances.9.Personal Growth:The process of learning photography and improving ones skills can be a journey of personal growth.It teaches patience,attention to detail,and the ability to see beauty in everyday life.10.Economic Value:In some cases,photography can have economic value.Professional photographers can make a living from their art,and historical or rare photographs can be sold for significant amounts.In conclusion,photography is more than just a hobby its a way of life that enriches our experiences and helps us to remember the beauty and significance of our lives.Whether its a simple snapshot from a smartphone or a carefully composed shot from a professional camera,each photograph has the power to capture a moment in time,preserving it for us to revisit and cherish.。
KODAK VISION3 50D 色彩肤色胶片 5203 7203的PDF文件说明书
KODAK VISION3 50DCOLOR NEGATIVE FILM 5203 / 7203TECHNICAL DATA / COLOR NEGATIVE FILM MARCH 2022H-1-5203 KODAK VISION3 50D Color Negative Film 5203/7203 is alow-speed daylight-balanced film. It is Kodak’s finest grainmotion picture film and ensures a pristine, clean imagesthat are full of color and detail.Like other films in the VISON3 Film family, VISION3 50D Filmfeatures unrivaled highlight latitude, flexibility inpostproduction, and proven archival stability. The expandeddynamic range allows for increased creative control in theextremes of exposure, especially high contrast daylightexteriors. Advances in grain and sharpness along withincreased exposure latitude also make this film ideal forrecorder output.Experience the improved extreme exposure performanceand consistent VISION3 Film family look along withunsurpassed image quality, real-world flexibility, and digitalpostproduction compatibility. Enjoy the benefits of thefinest grain capture film with the color and tonereproduction of the VISION3 Film portfolioBaseKODAK VISION3 50D Color Negative Films 5203 and 7203have an acetate safety base with rem-jet backing.StorageStore unexposed film at 13 C (55 F) or lower. For extendedstorage, store at -18 C (0 F) or lower. Process exposed filmpromptly.Store processed film according to the recommendations inISO 18911:2010, Imaging Materials - Processed SafetyPhotographic Films - Storage Practices.Short Term (less than 6 months)Long Term (more than 6 months)Unexposed film in original, sealedpackage13 C (55 F)RH below 60%-18 C(0 F)RH below 50%Exposed film, unprocessed-18 C(0 F)RH below 20%Not recommended.Process filmpromptly.Process film21 C (70 F)RH 20 to 50%2 C (36 F)RH 20 to 30%This relates to optimized film handling rather than preservation; static, dust-attraction and curl-related problems are generally minimized at the higher relative humidity. After usage, the film should be returned to the appropriate medium- or long-term storage conditions as soon as possible. Warm-up TimesTo prevent film telescoping, moisture condensation, and spotting, allow your film to warm to room temperature (21C/70F) before use:Film PackageRecommended Warm-up Time (Hours)8 C (15 F) Rise 39 C (70 F) Rise8 mm 1 1 ½16 mm 1 1 ½35 mm 3 5For more information about film storage and handling, see ANSI/PIMA ISO-18911, SMPTE RP131-2002, andKODAK Publication No. H-845, The Essential Reference Guide for Filmmakers, available online at/go/referenceguide.Darkroom RecommendationsDo not use a safelight. Handle unprocessed film in total darkness.ExposureExposure IndexesDaylight (5500K): 50Tungsten (3200K): 12 (with 80A filter)Use these indexes with incident or reflected light exposure meters and cameras marked for ISO or ASA speeds or exposure indexes. These indexes apply for meter readings of average subjects made from the camera position or for readings made from a gray card of 18 percent reflectance held close to and in front of the subject. For unusually light or dark colored subjects, decrease or increase the exposure i ndicated by the meter accordingly.Color BalanceThese films are balanced for exposure with daylight illumination (5500K). For other light sources, use the correction filters in the table that follows.Daylight (5500 K)None50 Metal Halide None50H.M.I.None50 KINO FLO 55None50 Tungsten (3000 K)WRATTEN 2 OpticalFilter / 80A12Tungsten (3200 K)WRATTEN 2 OpticalFilter / 80A 12KINO FLO 29 KINO FLO 32WRATTEN 2 OpticalFilter / 80A12Fluorescent, WarmWhite †Color CompensatingCC20M + CC05R25Fluorescent, CoolWhite †Color CompensatingCC40B20* These are approximate corrections only. Make final corrections during printing.† These are starting-point recommendations for trial exposures. If the kind of lamp is unknown, a KODAK Color Compensating Filter CC20M + CC10B can be used with an exposure index (EI) of 25.Note: Consult the manufacturer of high-intensity ultraviolet lamps for safety information on ultraviolet radiation and ozone generation.Exposure Table-Daylight IlluminationAt 24 frames per second (fps), 180-degree shutter opening, use this table for average subjects that contain a combination of light, medium, and dark colors:Lens Aperture f/1.4f/2f/2.8f/4f/5.6f/8f/11f/16FootcandlesRequired50100 200400800160032006400Reciprocity CharacteristicsYou do not need to make any filter corrections or exposure adjustments for exposure times from 1/1000 of a secondto 1 second.ProcessingProcess in Process ECN-2.Most commercial motion-picture laboratories provide a processing service for these films. See KODAK Publication No. H-24.07, Processing KODAK Color Negative Motion Picture Films, Module 7 available online at/go/h24, for more information on the solution formulas and the procedure for machine processing these films. There are also pre-packaged kits available for preparing the processing solutions. For more information on the KODAK ECN-2 Kit Chemicals, check Using KODAK Kit Chemicals in Motion Picture Film Laboratories KODAK Publication No. H-333, availableonline at /go/h333.IdentificationAfter processing, the product code numbers 5203, or 7203 emulsion, roll, and strip number identification, KEYKODE Numbers, and manufacturer/film identification code (ER) are visible along the length of the film.Post-ProductionScanningThe wider exposure latitude in KODAK VISION3 Films differentiate film capture from the limited dynamic range of digital capture. Digital "dodging and burning," a very powerful tool in the colorists' toolkit, is now even more powerful—up to two stops more image information canbe extracted from scene highlights in VISION3 Films.If traditional 10-bit scanner data encoding schemes are used to digitize films having this extended density range, highlight information captured on these films could be lost. Kodak has recommendations for extracting the full density range stored on highdynamic range films in a technical document titled Scanning Recommendations for Extended Dynamic Range Camera Films, available online at/go/scanning.Laboratory Aim Densities (LAD)To maintain optimum quality and consistency in the final prints, the laboratory must carefully control the color timing, printing, and duplicating procedures. To aid in color t iming and curve placement, negative originals should be t imed relative to Laboratory Aim Density (LAD) Control Film. The LAD Control Film provides both objective sensitometric control a nd subjective verification of the duplicating procedures used by the laboratory.In the LAD Control Method, the electronic color analyzer used for color timing is set-up with the LAD Control Film to produce a gray video display of the LAD patch, corresponding to 1.0 neutral density (gray) on the print. The negative printing original is then scene-to-scene timed. There are specific LAD values for each type of print or duplicating film that the original can be printed on. For print films, the LAD patch is printed to a neutral gray of 1.0 visual density. For duplicating films, the specified aims are at the center of the usable straight-line portion of the sensitometric curve of the film.Due to normal variations in exposure and processing of color negative films, particular scenes may not print exactly at the same printer lights as the LAD Control Film. The LAD Control Film is intended as a set-up tool for electronic color analyzers and printers. It is NOT a reference that every scene must match. Normal film-to-film and scene-to-scene exposure variability is accommodated by the color timing (grading) process, on an electronic color analyzer set up with the LAD Control Film. Normally exposed and processed color negatives will typically print well within the range of an additive printer setup with the LAD Control Film, although SIGNIFICANT or UNEXPECTED departures from this center point balance may indicate an exposure/filtration problem with the cinematography or with the process control. Some specialized films and/or specialized negative processing techniques (push-processing, pull-processing, "skip-bleach" processing, etc.) may require more extreme adjustment from the LAD printing condition to attain desired results.More information is contained in KODAK Publication H-61,Image StructureFor more information on image-structure characteristics, see KODAK Publication No. H-845, The Essential Reference Guide for Filmmakers available online at /go/referenceguide .Modulation Transfer FunctionThe "perceived" sharpness of any film depends on various components of the motion picture production system. The camera and projector lenses and film printers, among other factors, all play a role. But the specific sharpness of a film can be measured and is charted in the Modulation Transfer Function Curve.This graph shows a measure of the visual sharpness of this film. The x-axis, “Spatial Frequency,” refers to the number of sine waves per millimeter that can be resolved. The y-axis, “Response,”corresponds to film sharpness. The longer and flatter the line, the more sine waves per millimeter that can be resolved with a high degree of sharpness — and the sharper the film.rms GranularityThe “perception” of the graininess of any film is highly dependent on scene content, complexity, color, and density. Other factors, such as film age, processing,exposure conditions, and telecine transfer may also have significant effects.Read with a microdensitometer, using a 48-micrometre aperture. To find the rms Granularity value for a given density, find the density on the left vertical scale and follow horizontally to the characteristic curve and then go vertically (up or down) to the granularity curve. At that point, follow horizontally to theGranularity Sigma D scale on the right. Read the number and multiply by 1000 for the rms value.Note: This curve represents granularity based on modified measuringtechniques. Sensitometric and Diffuse RMS Granularity curves are produced on different equipment. A slight variation in curve shape may be noticed.SensitometryThe curves describe this film's response to red, green, and blue light. Sensitometric curves determine the change in density on the film for a given change in log exposure.Spectral SensitivityThese curves depict the sensitivity of this film to the spectrum of light. They are useful for determining,modifying, and optimizing exposure for blue- and green-screen special-effects work.Spectral Dye-Density CurvesThese curves depict the spectral absorption of the dyesformed when the film is processed. They are useful for adjusting or optimizing any device that scans or prints the film.Note: Cyan, Magenta, and Yellow Dye Curves are peak-normalized.Note: The sensitometric curves and data in this publication represent product tested under the conditions of exposure and processing specified. They are representative of production coatings, and therefore do not apply directly to a particular box or roll of photographic material. They do not represent standards or specifications that must be met by Eastman Kodak Company. The company reserves the right to change and improve product characteristics at any time.Available Roll Lengths and FormatsSee Kodak Motion Picture Products Catalog at /go/mpcatalog To order film in the United States and Canada, call 1- 800-356-3259, prompt 3.Worldwide customers can find the nearest sales office at /go/salesofficesKODAK VISION3 50D Color Negative Film 5203 / 7203KODAK Publication No. H-1-5203 Kodak, Keykode, Vision, and Wratten and the Kodak logo are trademarks.Revised 3-22© 2022 EASTMAN KODAK COMPANY。
介绍照片里的人用英语作文
In this photograph, we are presented with a group of individuals who, through their expressions and body language, reveal a sense of camaraderie and shared experience. The composition of the image is thoughtfully arranged, allowing each person to be recognized and appreciated for their unique presence.At the center of the group stands a tall, distinguished gentleman with a warm smile. His posture is confident, and his eyes sparkle with a sense of humor and wisdom. He is dressed in a tailored suit, which accentuates his stature and gives off an air of professionalism. His name is Mr. Johnson, a respected businessman who has made significant contributions to the community.To Mr. Johnsons right is a young woman with a vibrant aura. Her eyes are bright and full of life, and her smile is genuine and infectious. She is dressed in a smart casual outfit, which reflects her youthful energy and enthusiasm. This is Emily, a recent graduate who has just embarked on her career journey and is eager to make her mark in the world.On the left side of the photograph, we find an older woman with a gentle and nurturing demeanor. Her eyes are kind, and her posture exudes a sense of calm and serenity. She is adorned in a traditional dress that reflects her cultural heritage. This is Mrs. Thompson, a beloved teacher who has dedicated her life to educating and inspiring the next generation.In the background, we can see a few more individuals who add to the dynamic of the group. There is a young man with a thoughtful expression, perhaps contemplating the conversation at hand. Next to him is a woman with a determined look, suggesting that she is a strong and independent individual.The setting of the photograph is a welllit room with a warm and inviting atmosphere. The walls are adorned with artwork that adds a touch of elegance and sophistication to the space. The group is gathered around a large table, which is indicative of a meeting or a gathering of likeminded individuals.Overall, this photograph captures the essence of a diverse and dynamic group of people who come together to share ideas, experiences, and support one another. Each person brings their unique qualities and perspectives, creating a rich tapestry of human interaction that is both inspiring and heartwarming.。
海报英语作文
When it comes to writing an essay about a poster,there are several key elements to consider in order to create a wellrounded and engaging piece.Here are some steps and tips to guide you through the process:1.Introduction:Start your essay by introducing the poster.Mention the title,the artist or designer,and the context in which you encountered the poster.For example,The Save the Oceans poster,designed by renowned environmental artist Jane Doe,caught my attention at the local community center.2.Description:Provide a detailed description of the posters visual elements.Describe the colors,images,typography,and e sensory language to help the reader visualize the poster.For instance,The poster features a striking blue and green color palette, symbolizing the oceans depths,with bold white typography that commands attention.3.Content Analysis:Analyze the content of the poster.What message is it trying to convey?How does the imagery and text work together to communicate this message?For example,The central image of a sea turtle entangled in plastic waste is a powerful visual metaphor for the environmental crisis our oceans face.4.Design Critique:Evaluate the effectiveness of the posters design.Does the design support the message?Are there any elements that could be improved?For example, While the poster is visually compelling,the small print at the bottom could be made larger to ensure the call to action is not overlooked.5.Impact and Influence:Discuss the potential impact of the poster on its audience.How might it influence peoples attitudes or behaviors?For example,The posters emotional appeal could inspire viewers to take immediate action,such as reducing their plastic use or supporting ocean conservation efforts.6.Personal Reflection:Reflect on your personal reaction to the poster.How did it make you feel?Did it change your perspective on the issue?For example,Upon seeing the poster,I was deeply moved by the plight of marine life and felt a renewed sense of urgency to contribute to environmental preservation.7.Conclusion:Summarize your analysis and reiterate the posters effectiveness.End witha final thought or a call to action.For example,In conclusion,the Save the Oceans poster is a poignant reminder of our responsibility to protect our planets oceans,and it serves as a powerful tool for raising awareness and inspiring change.8.Citations and References:If you have referenced specific studies,statistics,or othersources in your essay,be sure to include proper citations and a reference list according to the citation style you are using e.g.,APA,MLA,Chicago.Remember to maintain a formal tone throughout your essay and to proofread your work for clarity,coherence,and grammatical accuracy.By following these steps,you can craft an insightful and persuasive essay about a poster.。
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Image Preservation Through PDF/A Frank L. Walker and George R. ThomaLister Hill National Center for Biomedical CommunicationsNational Library of MedicineBethesda, MarylandAbstractThe preservation of image collections is a goal of many libraries and organizations. Among the considerations for long-term preservation is the choice of file format. An emerging file format for preservation is PDF/A, which is a proposed international standard for long-term electronic document preservation. Since this file format can be used for image preservation, there are a number of considerations to be followed for converting image files to PDF/A, and also for ultimately migrating from PDF/A to successor file formats. As a result of research and development in electronic document delivery and file conversion, an Internet-based file migration system called MyMorph has been created at the National Library of Medicine. MyMorph was developed as a file migration service that allows the bulk conversion of electronic documents to PDF in a manner that minimizes certain aspects of the migration cost. The user interface permits file migration to proceed in batch mode, requiring minimal user interaction regardless of the number of files converted. After more than two years of use, the system is being modified to facilitate the creation of PDF/A files from source files consisting of scanned images. This paper details the design decisions for extending MyMorph to create image-based PDF/A files.IntroductionThe preservation of image collections into the distant future depends on a number of factors, including the cost of collection acquisition, storage, file replication and file migration. Among the considerations for preservation is the choice of the file format, one that is likely to be maintained and supported in the future. An emerging file format for preservation is PDF/A, a proposed international standard for long-term electronic document preservation.1PDF/A defines a subset of PDF version 1.4 features that would be mandatory, allowed or prohibited.2Mandatory features include an XML-based metadata object that provides important metadata for the document, such as author, subject, creator, creation date and modification date. If a document is modified for preservation purposes in the future, the metadata object would also be modified to record the history of how and why the file was changed. While many features of PDF version 1.4 are allowed in PDF/A, others are restricted or prohibited. Also, PDF/A prohibits the inclusion of movies, sounds and JavaScript (executable code).Two levels of conformance are possible for PDF/A: Level A and Level B. A file that meets Level A conformance is one that includes the full set of PDF/A features, including the document’s logical structure and content text stream in natural reading order. These two features facilitate navigation of the document, and the possible migration of the PDF/A file to a future file format. The logical structure specifies the document’s structure, which may include chapters, sections, footnotes, headers, figures and tables. This makes it possible for reader software to provide a user interface for easy navigation through the document. By maintaining the content text stream in natural reading order it is possible to present the text to physically impaired users. It also allows conversion of the content in its proper order for migration. Level A-conformant files also include a Unicode character map, which allows the retrieval of semantic properties of each character referenced in the file.A PDF/A file meets LevelB conformance if it satisfies all requirements except perhaps the logical structure, content text stream in logical reading order, and Unicode character map. A goal of PDF/A is to define an electronic document that retains its appearance over time. While an electronic document stored in PDF/A format may never change, the software tools for rendering it evolve over time. It is expected that a PDF/A file meeting Level A conformance will allow future software tools to render the document in its original appearance. Level A conformance also promises to allow migration of the file to future formats with little or no change in appearance. A file that meets Level B conformance should also retain its visual appearance as rendering tools change. However, the lack of logical structure, natural reading order of the text stream and Unicode character map may, in some cases, make it more difficult to migrate to future file formats.Organizations that want to create image archives may choose PDF/A as the preservation file format. A primary reason for choosing PDF/A as the archival format is the widespread availability of the Acrobat reader on many computing platforms. The Acrobat reader provides a userinterface that makes it easy to view monochrome, grayscaleand color images on a computer screen, and to print them. Images stored in many non-PDF formats, such as TIFF, can be converted to PDF/A without loss of information, and made viewable through the Acrobat reader. Since this reader is far more ubiquitous than viewers for most other image formats, PDF/A becomes a practical choice for image file format. This paper describes a prototype file migration system called MyMorph, developed at the National Library of Medicine, currently for creating PDF files via the Internet. It also describes the design considerations for modifying MyMorph to enable the creation of image-only PDF/A files.Considerations for PDF/A Image Archives There are a number of considerations to be taken into account when creating an image-only PDF/A archive. To migrate an existing image archive to PDF/A, or to create a PDF/A archive from newly scanned images, the first decision to be made is whether the PDF/A file should meet Level A or Level B conformance, denoted PDF/A-1A and PDF/A-1B respectively. It is probably not practical to achieve Level A conformance, since capture devices such as digital cameras or scanners that create raster images do not determine the logical structure, information flow, or Unicode character map. Adding these items manually would be costly. Level A conformance is primarily suitable for files containing text, rather than images. Files to be converted to PDF/A-1A would generally originate from word processors or other text-handling programs. This leaves PDF/A-1B the most practical alternative for a PDF/A image archive.The next question is whether PDF/A-1B is satisfactory for maintaining an image archive for the very long term. Suppose an organization creates an image-only PDF/A archive today. Will it be usable decades from now? If so, what would be necessary for a future generation to use it? First, we must assume that during this time an archivist would replicate the archive on new media simply because physical media decay with time. In order to use the archive, it would be necessary to have two things. One is the specification describing how the archive was created. The second would be the specification describing how the images would be used, whether for migration to a new file format, or for display on a specific device. A future programmer would have to understand both the PDF/A specifications, and the specifications for the new format. The specifications for PDF/A list a number of references that contain information necessary for understanding and using PDF/A files. The list of references is quite long, but some of the references are needed only for using PDF/A-1A files, not those that meet level B conformance. Table 1 is a typical list of documents needed by a future generation for migrating or using PDF/A-1B files that contain only images.1. PDF Reference version 1.4, Adobe2. Errata for above PDF Reference3. ISO specification for PDF/A4. Date and Time Formats, W3C5. ICC.1:1998-09 File Format for Color Profiles6. ICC.1A:1999-04 Addendum 2 to above7. ISO/IEC 646, Information technology – ISO 7-bitcoded character set for information exchange8. Extensible Markup Language (XML) 1.0, 3rdEdition, W3C9. RDF/XML Syntax Specification, W3C10. XMP Specification, Adobe11. Specifications for the internal storage format forimages stored in the file.Table 1. References for using PDF/A-1B Image Files The task for migrating the archive at a distant point in the future could be formidable, and it could take a future archivist/programmer several years to create software for using the archive, if it does not exist. However, if programmers of the future are at least as capable of current programmers, then the task seems manageable.MyMorphOne of the expectations for PDF/A is that software tools for creating, reading, rendering and verifying PDF/A files will become available once PDF/A becomes an ISO standard. One tool called MyMorph, developed as a file migration service at the Lister Hill National Center for Biomedical Communications, an R&D division of the National Library of Medicine (NLM), is currently used for creating PDF files via the Internet.3,4,5MyMorph is a technique for bulk file migration that is intended to minimize certain aspects of the migration cost. It is a Web-based approach that allows the conversion of a potentially large collection of electronic documents to PDF. It consists of client and server software that employ Simple Object Access Protocol (SOAP), a technology utilizing extensible markup language (XML) sent over the Internet via the Hypertext Transfer Protocol (HTTP). The MyMorph service relies on client software running on the user’s computer to send files via SOAP to a system at NLM called DocMorph, which can convert more than fifty different file formats to PDF, and return the results to the user. After two years of beta testing, version 1.0 of the MyMorph client software was released in July 2004. MyMorph currently has more than 4,000 registered users, who have converted thousands of files to PDF. The beta test confirmed that users found the software easy to learn, and the conversion to be fast. The bulk of the user population consists of small libraries that use MyMorph as part of their document delivery operation, and they tend to convert up to ten files at a time, but there are also a few users who have done large-scale migration of document collections to PDF.The software is designed to minimize the cost of migration for users in two ways. First, since MyMorph is freely available, anybody with a Windows-based computer and access to the Internet can use it. Second, the user interface permits file migration to proceed in batch mode with minimal user interaction regardless of whether a single file or hundreds at a time are converted. MyMorph is available through the DocMorph Web site at /docmorph.Figure 1 shows the architecture of the MyMorph/DocMorph system. There are six processors comprising the DocMorph server, with one processor designated as the Permission computer, and the five others as Worker computers. Users can access the system via Web browsers or MyMorph clients running on their computers. The browser or MyMorph client is granted permission to use the system by the Permission computer, which then routes the browser or MyMorph client to a Worker computer where the files are converted. DocMorph provides five conversion functions to Web browser users, including creating TIFF files, splitting multi-page TIFF files, creating PDF files, extracting text from files, or “reading aloud” the file using speech synthesis. MyMorph users are limited to the creation of PDF files. The advantage of using MyMorph over a browser for creating PDF files is that it requires very little user interface time, and this time is independent of the number of files to be converted.Figure 1. DocMorph/MyMorph System Architecture Since MyMorph is designed for converting potentially large collections of files to PDF, it is a candidate for creating archives of PDF/A files. After a thorough review of the proposed specifications for PDF/A, it was determined that MyMorph would be suitable for modification to create PDF/A-1B files from image files. While the system handles many types of files, including image files and word processing files, the immediate development will focus on image-only files. These file formats include BMP, DCM, DCX, DIB, FPX, GIF, ICO, JBIG, JPEG, MTV, PDB, PDM, PCD, PCX, PCM, PIX, PNG, PNM, PPM, PSD, RAS, TIFF, XBM and Ariel system GEDI files.The DocMorph software consists mainly of a combination of in-house designed C++ code, and two software packages, ImageMagick and Ghostscript, freely available on the Internet for a variety of computer platforms. ImageMagick is a collection of image processing utilities capable of handling over 90 different image file formats.6 DocMorph uses ImageMagick’s Convert utility to process most image file formats submitted to the system. As an example, it uses Convert to change a BMP format file to a color RGB format that is stored inside the PDF file.Design Considerations for PDF/AFour primary considerations were taken into account for redesigning the MyMorph/DocMorph system to create PDF/A-1B files from image files: image downsampling, lossy compression, color spaces and metadata. Because downsampling reduces the image resolution, the PDF/A specification recommends that images not be downsampled during conversion to PDF/A. Choice of a suitable compression algorithm for storing the image favors selecting lossless algorithms over lossy ones. Colors in PDF/A are specified in a device-independent manner to increase the flexibility for conversion to future file formats. Finally, PDF/A allows a complete description and history of the file to be stored within its XML-based metadata object. These four considerations are discussed next.Image downsampling is addressed in an appendix of the PDF/A specification. Although the specification does not prohibit image downsampling, it recommends that, as a best practice, images should not be downsampled when converted to PDF/A. The specification favors image quality over image size, and stresses the importance of preventing loss of information. Downsampling, the process of reducing the image size by eliminating data, is normally done to scale an image for display on a lower resolution device. If, for example, an image consists of bits 1, 2, 3, 4, 5, 6, and so on, then downsampling by a factor of 4 results in an image with bits 1, 5, 9 and so on. Other methods of downsampling may include linear interpolation and use of low pass filters with subsampling. While downsampling reduces the size of the image, it may reduce the image quality on high-resolution display devices. Even though current display hardware may not be capable of displaying the full resolution of an image, a future generation device may be capable of a more legible display. Since retaining image quality is of primeDocMorph Permission Computer DocMorph Worker Computer(s)importance in preservation, downsampling is not recommended. Preservationists still have to deal with image size and the capability of storage media for archiving an image collection, but trends in recent years tend to predict that storage density will continue to increase for some time to come. The DocMorph conversion software was redesigned to ensure that it did not downsample images during conversion to PDF/A.In addition to discouraging downsampling, the PDF/A specification also recommends against using lossy compression when converting images to PDF/A. Compression can be lossless, as in Group 4 compression for black and white images, or it can be lossy, as in JPEG. The PDF version 1.4 specification allows images to be stored within the PDF file using several image compression methods: JPEG compression for color and grayscale images; run-length compression, ITU-T Group 3, ITU-T Group 4 or JBIG2 compression for monochrome images; and Lempel-Ziv-Welch (LZW) and Flate compression for color, grayscale or black and white images. The PDF/A specification excludes LZW compression, since up until recently its use had legal ramifications. JPEG compression always results in loss of image quality, although the quality can be determined at the time the image is stored in JPEG format. Images in JPEG format tend to lose sharpness at edge boundaries (for example, a row of black pixels adjacent to a row of white pixels). Sharp edges tend to be blurred unless the image quality is selected to be high, i.e., compression ratio is low, which offsets the advantage of compression. To prevent loss of information during the conversion process to PDF/A, the specification’s “best practices” section would rule out JPEG compression. This leaves run-length compression, Group 3, Group4, JBIG2 and Flate as the choices for image compression, since they are all lossless. For monochrome images DocMorph uses Group 4 compression. Group 4 uses a two-dimensional compression algorithm that results in better compression than either run-length compression or Group 3 compression. Another possibility for compression of monochrome images is JBIG2, which promises to yield three to five times better compression than Group 4. Since the ImageMagick software does not handle JBIG2, this technique is not currently included in DocMorph.The only viable method for compressing color images in PDF/A is Flate. Newer versions of PDF allow lossless JPEG2000 compression, but since this recent standard is not available in version 1.4, it is also not permitted in PDF/A. Flate, also called ZIP, is a compression method that works well on images with large areas of single colors or repeating patterns. Flate uses a combination of the LZ77 algorithm (a non-proprietary precursor to LZW) and Huffman coding.7,8 For the PDF/A development, DocMorph was modified to use Flate compression to compress grayscale and color images using the freely available ZLIB library of software compression routines.9A third consideration for modifying DocMorph to create PDF/A files is the use of color spaces. A color space, which can be device-dependent or device-independent, is the range of colors in which color images can be represented. A device-dependent color space is a way of describing the colors in an image that allows it to be displayed on a specific device, whether a hardcopy printer or softcopy monitor. While PDF version 1.4 supports three types of device-dependent color spaces (DeviceGray, DeviceRGB and DeviceCMYK), four types of device-independent color spaces (CalGray, CalRGB, Lab and ICCBased), and four special color spaces (Index, Pattern, Separation and DeviceN), PDF/A restricts the color space to be one of the four device-independent color spaces. Using a device-independent color space allows more flexibility in converting the PDF/A file to future file formats, and for display on a variety of devices. If an ICCBased color space is used, then PDF/A requires the color space to be embedded in the PDF/A file. The International Color Consortium, or ICC, is an industry consortium of about 70 member organizations whose goal is to promote use of a vendor-neutral cross-platform color management system. It has developed a number of ICC Profiles that contain transforms to and from device color spaces to the Profile Connection Space, which is device-independent. Because of the general-purpose nature of DocMorph and MyMorph, the user is not required to specify how the colors in the submitted file are rendered, i.e., whether the colors are device-dependent (such as RGB or CMYK), or device-independent. For initial development, it is assumed that color images have been rendered using sRGB, which is the default color space for multimedia applications and images posted on Web sites, and was developed through work at Microsoft and Hewlett-Packard.10Images rendered using sRGB can be displayed on most uncalibrated monitors fairly accurately. It may be incorrect to assume that images submitted to the system are rendered as sRGB. Because this may cause some colors to be displayed inaccurately, our design will allow the user to choose the color space prior to submitting the files for conversion.The chief modification to DocMorph to accommodate the sRGB color space consists of using an OutputIntents dictionary located in the Catalog object that has GTS_PDFA1 as the value of its S key, and the sRGB profile stream as the value of the DestOutputProfile key. Figure 2 is a typical example of the OutputIntents array and dictionary.28 0 obj % ICC Profile Stream<</N 3/Length 3144>>stream00 00 0C 48 4C …endstreamendobj/OutputIntents[<</Type /OutputIntent/S /GTS_PDFA1/DestOutputProfile 28 0 obj/OutputConditionIdentifier (sRGB)/RegistryName ()>>]Figure 2. Example OutputIntents Array and Dictionary The final consideration for modifying DocMorph to handle PDF/A files is metadata. The requirement for PDF/A files to contain a metadata object is critical for preservation, since the metadata object includes pertinent information about who created the file, when it was created, when it was modified, and the reasons for modification. Thus the metadata object contains the complete history of the file. Prior to its current redesign, DocMorph created PDF files containing a Document Information Dictionary object, consisting of the name of the creator and date of creation. The PDF/A specification requires synchronization between the metadata object and Document Information Dictionary, so that the information in the latter must also exist in the metadata object. DocMorph was modified to satisfy this requirement, so that when it creates the PDF/A file the entries in the Document Information Dictionary and the metadata object are consistent. To ensure that it creates a valid metadata object, DocMorph software uses the XMP Toolkit from Adobe Systems, Inc. This toolkit provides source code for implementing the Extensible Metadata Platform, a specification from Adobe that provides an XML-based framework for working effectively with metadata.11 DocMorph was modified to create a minimal metadata object, containing the CreatorTool, Producer, CreateDate, ModifyDate, DocumentID, part and conformance fields.In addition to the four considerations for DocMorph modification, several minor modifications were necessary, one of which was to include the ID parameter in the file trailer dictionary. The ID parameter uniquely identifies the file, and consists of an array of two uniquely created strings that are initially identical. While the first string is fixed, the second string changes whenever the file is modified. The new value of the second string is based on the file’s contents at the time the file is modified. This is what a typical ID looks like when first created:[<83f48392eefa8bc9028793748495833a><83f48392eefa8bc9028793748495833a>]The Next StepsIt is expected that tools for creating and validating PDF/A files will become available after PDF/A becomes an accepted standard. We are waiting for PDF/A validation tools to appear before finalizing our modifications to MyMorph/DocMorph. This will allow us to verify that the files created by the system are valid PDF/A files, and conform to PDF/A-1B. We are also considering giving the user options for selecting the color space to be used in the file. Finally, we plan to explore modifying the system to store black and white images in JBIG2 format within PDF/A files, which should result in three to five times better compression than Group 4 compression. This would be of interest to image preservationists concerned with collection size.SummaryPDF/A is an emerging file format specification for preserving electronic documents. It permits two levels of conformance, each of which promises to provide long-term preservation. An analysis of the specification reveals that image files preserved through PDF/A are best suited for level B conformance. An existing system for migrating files to PDF via the Internet called MyMorph is being modified to permit migration of image files to PDF/A files with level B conformance. The design factors considered for system modification include image downsampling, lossy compression, color spaces and metadata.References1. ISO/DIS 19005-1, Document management – Electronicdocument file format for long-term preservation – Part 1: Use of PDF 1.4 (PDF/A-1).2. Adobe Systems Incorporated, PDF Reference: AdobePortable Document Format, Version 1.4, Addison-Wesley, Boston, 3rd edition (2001).3. Frank L. Walker and George R. Thoma, Web-basedDocument Image Processing. Proceedings of IS&T/SPIE Conference on Internet Imaging, San Jose, California, 268-277 (January 2000).4. Frank L. Walker and George R. Thoma, A SOAP-EnabledSystem for an Online Library Service. Proceedings of InfoToday 2002. Medford N.J.: Information Today, 320-329 (2002).5. Frank L. Walker and George R. Thoma, A Web-BasedParadigm for File Migration. Proceedings of IS&T’s 2004 Archiving Conference. SpringField, VA: IS&T: The Society for Imaging Science and Technology, 93-97 (April 2004).6. ImageMagick is available at .7. RFC 1950, ZLIB Compressed Data Format SpecificationVersion 3.3, /rfcs/rfc1950.html.8. RFC 1951, DEFLATE Compressed Data Format Specification,Version 1.3, available at/rfcs/rfc1951.html.9. ZLIB is available at /zlib.10. Mary Nielsen and Michael Stokes, The Creation of the sRGBICC Profile. IS&T/SID Sixth Color Imaging Conference:Color Science, Systems and Applications. Scottsdale,Arizona, 253-257 (November 1998).11. Adobe Systems Incorporated, XMP Specification (2004).BiographyFrank L. Walker received his B.S. and M.S. degrees in electrical engineering from the University of Maryland. Since he joined the National Library of Medicine in 1979, he has designed, developed, performed research and published a number of papers on computer systems utilizing electronic imaging, primarily for the purpose of electronic document storage, retrieval, transmission and use. His current interest is in developing software and systems for improving the delivery and use of biomedical library information.George R. Thoma is a Branch Chief at an R&D division of the U.S. National Library of Medicine. He directs R&D programs in document image analysis, biomedical image processing, animated virtual books, and related areas. He earned a B.S. from Swarthmore College, and the M.S. and Ph.D. from the University of Pennsylvania, all in electrical engineering. Dr. Thoma is a Fellow of the SPIE, the International Society for Optical Engineering.。