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66-673: PDF files of current and past Snell standards are available on the Snell Web site. To qualify for Snell certification, the helmet must pass a series of tests. The tests are determined depending on the application and the requirements of the standard. Snell Standards significantly surpass those set by the United States Department of Transportation (DOT), the American National Standards Institute (ANSI), ASTM International (ASTM) and

132-631: A page description . PDF has (as of version 2.0) 25 graphics state properties, of which some of the most important are: As in PostScript, vector graphics in PDF are constructed with paths . Paths are usually composed of lines and cubic Bézier curves , but can also be constructed from the outlines of text. Unlike PostScript, PDF does not allow a single path to mix text outlines with lines and curves. Paths can be stroked, filled, fill then stroked, or used for clipping . Strokes and fills can use any color set in

198-496: A PDF are: In later PDF revisions, a PDF document can also support links (inside document or web page), forms, JavaScript (initially available as a plugin for Acrobat 3.0), or any other types of embedded contents that can be handled using plug-ins. PDF combines three technologies: PostScript is a page description language run in an interpreter to generate an image. It can handle graphics and has standard features of programming languages such as branching and looping . PDF

264-455: A PDF. Within text strings, characters are shown using character codes (integers) that map to glyphs in the current font using an encoding . There are several predefined encodings, including WinAnsi , MacRoman , and many encodings for East Asian languages and a font can have its own built-in encoding. (Although the WinAnsi and MacRoman encodings are derived from the historical properties of

330-420: A PostScript file could be accurately rendered only as the cumulative result of executing all preceding commands to draw all previous pages—any of which could affect subsequent pages—plus the commands to draw that particular page, and there was no easy way to bypass that process to skip around to different pages. Traditionally, to go from PostScript to PDF, a source PostScript file (that is, an executable program)

396-477: A Web browser plugin without waiting for the entire file to download, since all objects required for the first page to display are optimally organized at the start of the file. PDF files may be optimized using Adobe Acrobat software or QPDF . Page dimensions are not limited by the format itself. However, Adobe Acrobat imposes a limit of 15 million by 15 million inches, or 225 trillion in (145,161 km ). The basic design of how graphics are represented in PDF

462-502: A computational method influenced by the sciences of cybernetics, autopoiesis and system theories, and challenging notions of reason and cognition, perception and memory, emotions and affection. Any form of interface between the end user / audience and the medium may be considered interactive. Interactive media is not limited to electronic media or digital media. Board games , pop-up books , flip books and constellation wheels are all examples of printer interactive media. Books with

528-593: A critical role in building relationships. Organizations also use interactive media to go further than basic marketing and develop more positive behavioral relationships. The use of interactive media, alongside immersive media, also has the additional benefit to providing further realism to creating relational bonds in virtual settings. Through the use of this technology, new types of relationships can be formed as well as strengthening preexisting ones. Interactive media has given way to new distractions which can lead to public safety issues. Digital distractions are heightened by

594-437: A daily basis is Delta Airlines 's "Photon Shower". This device was developed as a collaboration between Delta Airlines and Professor Russell Foster of Cambridge University . The device is designed to reduce the effect of jet lag on customers that often take long flights across time zones. The interactivity is evident because of how it solves this problem. By observing what time zones a person has crossed and matching those to

660-693: A learning environment helps children increase communication skills and their attitudes about learning. Children who use educational computer software are often found using more complex speech patterns and higher levels of verbal communication. A study found that basic interactive books that simply read a story aloud and highlighted words and phrases as they were spoken were beneficial for children with lower reading abilities. Children have different styles of learning, and interactive media helps children with visual, verbal, auditory, and tactile learning styles. Furthermore, studies conducted using interactive, immersive media (such as virtual reality ) has proven effects on

726-452: A page description as an inline image .) Images are typically filtered for compression purposes. Image filters supported in PDF include the following general-purpose filters: Normally all image content in a PDF is embedded in the file. But PDF allows image data to be stored in external files by the use of external streams or Alternate Images . Standardized subsets of PDF, including PDF/A and PDF/X , prohibit these features. Text in PDF

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792-417: A paper for a project then code-named Camelot, in which he proposed the creation of a simplified version of PostScript called Interchange PostScript (IPS). Unlike traditional PostScript, which was tightly focused on rendering print jobs to output devices, IPS would be optimized for displaying pages to any screen and any platform. Adobe Systems made the PDF specification available free of charge in 1993. In

858-439: A printing device. PostScript was not intended for long-term storage and real-time interactive rendering of electronic documents to computer monitors , so there was no need to support anything other than consecutive rendering of pages. If there was an error in the final printed output, the user would correct it at the application level and send a new print job in the form of an entirely new PostScript file. Thus, any given page in

924-469: A result, files that use a small amount of transparency might be viewed acceptably by older viewers, but files making extensive use of transparency could be viewed incorrectly by an older viewer. The transparency extensions are based on the key concepts of transparency groups , blending modes , shape , and alpha . The model is closely aligned with the features of Adobe Illustrator version 9. The blend modes were based on those used by Adobe Photoshop at

990-501: A simple table of contents or index may be considered interactive due to the non-linear control mechanism in the medium, but are usually considered non-interactive since the majority of the user experience is non-interactive reading. Interactive media is helpful in the four development dimensions in which young children learn: social and emotional, language development, cognitive and general knowledge, and approaches toward learning. Using computers and educational computer software in

1056-473: A stream may be used instead of the ASCII cross-reference table and contains the offsets and other information in binary format. The format is flexible in that it allows for integer width specification (using the /W array), so that for example, a document not exceeding 64  KiB in size may dedicate only 2 bytes for object offsets. At the end of a PDF file is a footer containing If a cross-reference stream

1122-440: A technical critique and rebuttal to the article, available at their Web site, which asserts that there are no viable data to indicate that a softer liner or a softer shell could result in less severe head injuries. In September 2009, New York Times published a follow-up article which cited the 2005 Motorcyclist article; SMF rebutted it as well. Snell Memorial Foundation's 2010 standard for motorcycle helmets now conforms to one of

1188-428: A unique problem or set of problems. Interactive media is not limited to a professional environment, it can be used for any technology that responds to user actions. This can include the use of JavaScript and AJAX in web pages, but can also be used in programming languages or technology that has similar functionality. One of the most recent innovations to use interactivity that solves a problem that individuals have on

1254-502: A variety of content besides flat text and graphics including logical structuring elements, interactive elements such as annotations and form-fields, layers, rich media (including video content), three-dimensional objects using U3D or PRC , and various other data formats . The PDF specification also provides for encryption and digital signatures , file attachments, and metadata to enable workflows requiring these features. The development of PDF began in 1991 when John Warnock wrote

1320-415: Is a subset of PostScript, simplified to remove such control flow features, while graphics commands remain. PostScript was originally designed for a drastically different use case : transmission of one-way linear print jobs in which the PostScript interpreter would collect a series of commands until it encountered the showpage command, then execute all the commands to render a page as a raster image to

1386-464: Is also a shading pattern , which draws continuously varying colors. There are seven types of shading patterns of which the simplest are the axial shading (Type 2) and radial shading (Type 3). Raster images in PDF (called Image XObjects ) are represented by dictionaries with an associated stream. The dictionary describes the properties of the image, and the stream contains the image data. (Less commonly, small raster images may be embedded directly in

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1452-469: Is called an embedded font while the former is called an unembedded font . The font files that may be embedded are based on widely used standard digital font formats: Type 1 (and its compressed variant CFF), TrueType , and (beginning with PDF 1.6) OpenType . Additionally PDF supports the Type 3 variant in which the components of the font are described by PDF graphic operators. Fourteen typefaces, known as

1518-410: Is empirically observed with motorcycle crashes) for repeated hard impact on the same section of helmet. This is not what happens in an actual crash the standard actually poses a threat to safety. Helmet standards call out various tests to evaluate helmet performance in reducing preventable brain injuries and fatalities. Helmet testing in a lab is not a simulation of a real crash. The most essential part of

1584-418: Is not being used, the footer is preceded by the trailer keyword followed by a dictionary containing information that would otherwise be contained in the cross-reference stream object's dictionary: Within each page, there are one or multiple content streams that describe the text, vector and images being drawn on the page. The content stream is stack-based , similar to PostScript. There are two layouts to

1650-544: Is not required in situations where a PDF file is intended only for print. Since the feature is optional, and since the rules for tagged PDF were relatively vague in ISO 32000-1, support for tagged PDF among consuming devices, including assistive technology (AT), is uneven as of 2021. ISO 32000-2, however, includes an improved discussion of tagged PDF which is anticipated to facilitate further adoption. An ISO-standardized subset of PDF specifically targeted at accessibility, PDF/UA ,

1716-485: Is one demonstrated way in which interactive media is able to meet commercial needs and provide alternative revenue for business. Studies show that through the use of immersive, interactive media business are expected greater marketing impacts. Media in which information is provided in interactive means. An example would be Geographic Information Systems , like those built upon the ArcGIS framework which provides users with

1782-434: Is organized using ASCII characters, except for certain elements that may have binary content. The file starts with a header containing a magic number (as a readable string) and the version of the format, for example %PDF-1.7 . The format is a subset of a COS ("Carousel" Object Structure) format. A COS tree file consists primarily of objects , of which there are nine types: Comments using 8-bit characters prefixed with

1848-477: Is related to the concepts interaction design , new media , interactivity , human computer interaction , cyberculture , digital culture , interactive design , and can include augmented reality and virtual reality . An essential feature of interactivity is that it is mutual: user and machine each take an active role. Most interactive computing systems are for some human purpose and interact with humans in human contexts. Interactive media are an instance of

1914-402: Is represented by text elements in page content streams. A text element specifies that characters should be drawn at certain positions. The characters are specified using the encoding of a selected font resource . A font object in PDF is a description of a digital typeface . It may either describe the characteristics of a typeface, or it may include an embedded font file . The latter case

1980-439: Is used as the basis for generating PostScript-like PDF code (see, e.g., Adobe Distiller ). This is done by applying standard compiler techniques like loop unrolling , inlining and removing unused branches, resulting in code that is purely declarative and static. The end result is then packaged into a container format , together with all necessary dependencies for correct rendering (external files, graphics, or fonts to which

2046-447: Is very similar to that of PostScript, except for the use of transparency, which was added in PDF 1.4. PDF graphics use a device-independent Cartesian coordinate system to describe the surface of a page. A PDF page description can use a matrix to scale , rotate , or skew graphical elements. A key concept in PDF is that of the graphics state , which is a collection of graphical parameters that may be changed, saved, and restored by

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2112-662: The Hurt Report , who described the Snell standards as "a little bit excessive," and Dr. Jim Newman, former head of Snell Memorial Foundation, who characterized the then-current Snell Memorial Foundation standard as a "marketing gimmick." The article reported that a softer absorption material would transfer less g-force to the head in the most common motorcycle accidents than the stiffer absorption material required in Snell-certified helmets. Snell Memorial Foundation released

2178-566: The PostScript language, each PDF file encapsulates a complete description of a fixed-layout flat document, including the text, fonts , vector graphics , raster images and other information needed to display it. PDF has its roots in "The Camelot Project" initiated by Adobe co-founder John Warnock in 1991. PDF was standardized as ISO 32000 in 2008. The last edition as ISO 32000-2:2020 was published in December 2020. PDF files may contain

2244-410: The U.S. Consumer Product Safety Commission 's 16 CFR Part 1203. Industry consensus standards such as ASTM and ANSI, and government mandatory standards such as ECE, DOT and CPSC, are all minimum standards. Snell Standards are voluntary and call for premium level of protection in headgear while satisfying the minimum requirements set for different jurisdictions. Research shows that in higher severity tests,

2310-538: The Windows and Macintosh operating systems, fonts using these encodings work equally well on any platform.) PDF can specify a predefined encoding to use, the font's built-in encoding or provide a lookup table of differences to a predefined or built-in encoding (not recommended with TrueType fonts). The encoding mechanisms in PDF were designed for Type 1 fonts, and the rules for applying them to TrueType fonts are complex. For large fonts or fonts with non-standard glyphs,

2376-419: The standard 14 fonts , have a special significance in PDF documents: These fonts are sometimes called the base fourteen fonts . These fonts, or suitable substitute fonts with the same metrics, should be available in most PDF readers, but they are not guaranteed to be available in the reader, and may only display correctly if the system has them installed. Fonts may be substituted if they are not embedded in

2442-603: The DOT-only helmets transmitted significantly greater shocks than Snell certified helmets. Snell Standards are updated about every five years. These updates are based on new scientific research and improved, available manufacturing technologies. As such, and in addition to other factors such as typical use wear and tear, Snell recommends that helmets be replaced approximately every five years to ensure good safety. For motorcycle safety Snell standards are inferior to ECE and FIM equivalents, they disregard crumple and "softness" (that

2508-429: The PDF files: non-linearized (not "optimized") and linearized ("optimized"). Non-linearized PDF files can be smaller than their linear counterparts, though they are slower to access because portions of the data required to assemble pages of the document are scattered throughout the PDF file. Linearized PDF files (also called "optimized" or "web optimized" PDF files) are constructed in a manner that enables them to be read in

2574-554: The adults to believe that it distracts children more than it benefits them. The media which allows several geographically remote users to interact synchronously with the media application/system is known as Distributed Interactive Media. Some common examples of this type of Media include Online Gaming, Distributed Virtual Environment, Whiteboards which are used for interactive conferences and many more. Interactive medias assist in commercial ventures, such as those incorporating media using virtual and augmented technologies. Virtual tours

2640-431: The basic known sleep cycles of the individual, the machine is able to predict when a person's body is expecting light, and when it is expecting darkness. It then stimulates the individual with the appropriate light source variations for the time, as well as an instructional card to inform them of what times their body expects light and what times it expects darkness. Growth of interactive media continues to advance today, with

2706-508: The contents. PDF 2.0 defines 256-bit AES encryption as the standard for PDF 2.0 files. The PDF Reference also defines ways that third parties can define their own encryption systems for PDF. PDF files may be digitally signed, to provide secure authentication; complete details on implementing digital signatures in PDF are provided in ISO 32000-2. PDF files may also contain embedded DRM restrictions that provide further controls that limit copying, editing, or printing. These restrictions depend on

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2772-411: The document refers), and compressed . Modern applications write to printer drivers that directly generate PDF rather than going through PostScript first. As a document format, PDF has several advantages over PostScript: Its disadvantages are: PDF since v1.6 supports embedding of interactive 3D documents: 3D drawings can be embedded using U3D or PRC and various other data formats. A PDF file

2838-411: The document root. This dictionary contains an array of Optional Content Groups (OCGs), each describing a set of information and each of which may be individually displayed or suppressed, plus a set of Optional Content Configuration Dictionaries, which give the status (Displayed or Suppressed) of the given OCGs. A PDF file may be encrypted , for security, in which case a password is needed to view or edit

2904-538: The early years PDF was popular mainly in desktop publishing workflows, and competed with several other formats, including DjVu , Envoy , Common Ground Digital Paper, Farallon Replica and even Adobe's own PostScript format. PDF was a proprietary format controlled by Adobe until it was released as an open standard on July 1, 2008, and published by the International Organization for Standardization as ISO 32000-1:2008, at which time control of

2970-1054: The educational impacts of students diagnosed with autism spectrum disorder. Through the use of additional sensors and specialized equipment, immersive medias have been questioned on their effectiveness to include students who may be considered neurodivergent . Interactive media can often be considered as highly stimulating, which raised concerns for overstimulation and potential triggers of reaction for particular students. Interactive media has also been used under multiple professions to provide training opportunities, such as its use in medical training and education. Interactive media makes technology more intuitive to use. Interactive products such as smartphones, iPad's/iPod's, interactive whiteboards and websites are all easy to use. The easy usage of these products encourages consumers to experiment with their products rather than reading instruction manuals. Interactive media promotes dialogic communication. This form of communication allows senders and receivers to build long term trust and cooperation. This plays

3036-406: The full implementation of the ISO 32000-1 specification. These proprietary technologies are not standardized, and their specification is published only on Adobe's website. Many of them are not supported by popular third-party implementations of PDF. ISO published version 2.0 of PDF, ISO 32000-2 in 2017, available for purchase, replacing the free specification provided by Adobe. In December 2020,

3102-402: The graphics state, including patterns . PDF supports several types of patterns. The simplest is the tiling pattern in which a piece of artwork is specified to be drawn repeatedly. This may be a colored tiling pattern , with the colors specified in the pattern object, or an uncolored tiling pattern , which defers color specification to the time the pattern is drawn. Beginning with PDF 1.3 there

3168-494: The imaging model. A tagged PDF (see clause 14.8 in ISO 32000) includes document structure and semantics information to enable reliable text extraction and accessibility . Technically speaking, tagged PDF is a stylized use of the format that builds on the logical structure framework introduced in PDF 1.3. Tagged PDF defines a set of standard structure types and attributes that allow page content (text, graphics, and images) to be extracted and reused for other purposes. Tagged PDF

3234-459: The impact that it will have on their family lives. This is not necessarily because they are opposed to technology, but because they fear that it will lessen the time that they get to spend with their children. Studies have shown that although interactive media is able to connect families together when they are unable to physically, the dependence on these media also continues to persist even when there are opportunities for family time, which often leads

3300-527: The industry, displaying mass examples of interactive medias and their impacts such as those in the Digital Humanities space where interactive media was able to be used for research purposes. Interactive media can be implemented using a variety of platforms and applications that use technology. Some examples include mobile platforms such as touch screen smartphones and tablets, as well as other interactive mediums that are created exclusively to solve

3366-432: The magazine's criticisms, that a larger head will also be a heavier head. Portable Document Format This is an accepted version of this page Portable Document Format ( PDF ), standardized as ISO 32000 , is a file format developed by Adobe in 1992 to present documents , including text formatting and images, in a manner independent of application software , hardware , and operating systems . Based on

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3432-465: The means to interact with locational data in various ways such as collecting, storing and manipulating. A couple of basic examples of interactive media are websites and mobile applications. Websites, especially social networking websites provide the interactive use of text and graphics to its users, who interact with each other in various ways such as chatting, posting a thought or picture and so forth. The ImmersiveMe convention brings together those in

3498-607: The necessity for user input and response to media requests. Smartphones are a prevalent form of interactive media, and their excessive use can lead to bedtime procrastination . Mobile phone use that keeps individuals up at night causes adverse health effects such as fatigue and headaches. The introduction of interactive media has greatly affected the lives and inner workings of families, with many family activities having integrated with technology quite seamlessly, allowing both children and parents to adapt to it as they see fit. However, parents have also become increasingly worried about

3564-440: The objects in the file, and also allows for small changes to be made without rewriting the entire file ( incremental update ). Before PDF version 1.5, the table would always be in a special ASCII format, be marked with the xref keyword, and follow the main body composed of indirect objects. Version 1.5 introduced optional cross-reference streams , which have the form of a standard stream object, possibly with filters applied. Such

3630-552: The percent sign ( % ) may be inserted. Objects may be either direct (embedded in another object) or indirect . Indirect objects are numbered with an object number and a generation number and defined between the obj and endobj keywords if residing in the document root. Beginning with PDF version 1.5, indirect objects (except other streams) may also be located in special streams known as object streams (marked /Type /ObjStm ). This technique enables non-stream objects to have standard stream filters applied to them, reduces

3696-448: The reader software to obey them, so the security they provide is limited. Rich media Interactive media normally refers to products and services on digital computer-based systems which respond to the user's actions by presenting content such as text , moving image , animation , video and audio . Since its early conception, various forms of interactive media have emerged with impacts on educational and commercial markets. With

3762-481: The rise of decision-driven media, concerns surround the impacts of cybersecurity and societal distraction. Interactive media is a method of communication in which the output from the media comes from the input of the users. Interactive media works with the user's participation. The media still has the same purpose but the user's input adds interaction and brings interesting features to the system for better enjoyment. The analogue videodisc developed by NV Philips

3828-502: The second edition of PDF 2.0, ISO 32000-2:2020, was published, with clarifications, corrections, and critical updates to normative references (ISO 32000-2 does not include any proprietary technologies as normative references). In April 2023 the PDF Association made ISO 32000-2 available for download free of charge. A PDF file is often a combination of vector graphics , text, and bitmap graphics . The basic types of content in

3894-423: The size of files that have large numbers of small indirect objects and is especially useful for Tagged PDF . Object streams do not support specifying an object's generation number (other than 0). An index table, also called the cross-reference table, is located near the end of the file and gives the byte offset of each indirect object from the start of the file. This design allows for efficient random access to

3960-432: The special encodings Identity-H (for horizontal writing) and Identity-V (for vertical) are used. With such fonts, it is necessary to provide a ToUnicode table if semantic information about the characters is to be preserved. A text document which is scanned to PDF without the text being recognised by optical character recognition (OCR) is an image, with no fonts or text properties. The original imaging model of PDF

4026-577: The specification passed to an ISO Committee of volunteer industry experts. In 2008, Adobe published a Public Patent License to ISO 32000-1 granting royalty-free rights for all patents owned by Adobe necessary to make, use, sell, and distribute PDF-compliant implementations. PDF 1.7, the sixth edition of the PDF specification that became ISO 32000-1, includes some proprietary technologies defined only by Adobe, such as Adobe XML Forms Architecture (XFA) and JavaScript extension for Acrobat, which are referenced by ISO 32000-1 as normative and indispensable for

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4092-477: The testing is an assessment of the helmet’s total impact energy management capability. Snell Standards demand premium level of head protection above government minimum standard requirements set by DOT and ECE. In 2005, Motorcyclist magazine wrote an in-depth article discussing helmet testing and safety. The article included criticism of Snell Memorial Foundation standards by prominent head injury and helmet design experts, including Dr. Harry Hurt , author of

4158-448: The time. When the PDF 1.4 specification was published, the formulas for calculating blend modes were kept secret by Adobe. They have since been published. The concept of a transparency group in PDF specification is independent of existing notions of "group" or "layer" in applications such as Adobe Illustrator. Those groupings reflect logical relationships among objects that are meaningful when editing those objects, but they are not part of

4224-481: Was opaque, similar to PostScript, where each object drawn on the page completely replaced anything previously marked in the same location. In PDF 1.4 the imaging model was extended to allow transparency. When transparency is used, new objects interact with previously marked objects to produce blending effects. The addition of transparency to PDF was done by means of new extensions that were designed to be ignored in products written to PDF 1.3 and earlier specifications. As

4290-514: Was first published in 2012. With the introduction of PDF version 1.5 (2003) came the concept of Layers. Layers, more formally known as Optional Content Groups (OCGs), refer to sections of content in a PDF document that can be selectively viewed or hidden by document authors or viewers. This capability is useful in CAD drawings, layered artwork, maps, multi-language documents, etc. Basically, it consists of an Optional Content Properties Dictionary added to

4356-401: Was the pioneering technology for interactive media. Additionally, there are several elements that encouraged the development of interactive media including the following: All of the prior elements contributed in the development of the main hardware and software systems used in interactive media. Though the word media is plural, the term is often used as a singular noun. Interactive media

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