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46-492: The encoder and decoder have been part of the free, open-source library libavcodec in the project FFmpeg since June 2003. FFV1 is also included in ffdshow and LAV Filters , which makes the video codec available to Microsoft Windows applications that support system-wide codecs over Video for Windows (VfW) or DirectShow . FFV1 has been standardized at the IETF under RFC 9043. The European Broadcasting Union (EBU) lists FFV1 under

92-465: A zigzag scan pattern that shows how MPEG video codecs handle entropy encoding . On March 13, 2011, a group of FFmpeg developers decided to fork the project under the name Libav . The event was related to an issue in project management, in which developers disagreed with the leadership of FFmpeg. On January 10, 2014, two Google employees announced that over 1000 bugs had been fixed in FFmpeg during

138-838: A Call For Papers (CFP) or a Call For Abstracts, which is sent to prospective presenters and explains how to submit their abstracts or papers. It describes the broad theme and lists the meeting's topics and formalities such as what kind of abstract (summary) or paper has to be submitted, to whom, and by what deadline . A CFP is usually distributed using a mailing list or on specialized online services. Contributions are usually submitted using an online abstract or paper management service. Predatory conferences or predatory meetings are meetings set up to appear as legitimate scientific conferences but which are exploitative as they do not provide proper editorial control over presentations, and advertising can include claims of involvement of prominent academics who are, in fact, uninvolved. They are an expansion of

184-410: A conference is performed by active RFID that may indicate wilfully identified and relatively located upon approach via electronic tags. Conferences are usually organized either by a scientific society or by a group of researchers with a common interest. Larger meetings may be handled on behalf of the scientific society by a Professional Conference Organiser or PCO. The meeting is announced by way of

230-436: A short abstract of their presentation, which will be reviewed before the presentation is accepted for the meeting. Some organizers, and therefore disciplines require presenters to submit a paper, which is peer reviewed by members of the program committee or referees chosen by them. In some disciplines, such as English and other languages, it is common for presenters to read from a prepared script. In other disciplines such as

276-401: A simple media player, and ffprobe , a command-line tool to display media information. Among included libraries are libavcodec , an audio/video codec library used by many commercial and free software products, libavformat (Lavf), an audio/video container mux and demux library, and libavfilter, a library for enhancing and editing filters through a GStreamer -like filtergraph. FFmpeg

322-442: A suite of libraries and programs for handling video, audio, and other multimedia files and streams. At its core is the command-line ffmpeg tool itself, designed for processing video and audio files. It is widely used for format transcoding , basic editing (trimming and concatenation ), video scaling , video post-production effects, and standards compliance ( SMPTE , ITU ). FFmpeg also includes other tools: ffplay ,

368-655: A variety of application-specific integrated circuits (ASICs) for audio/video compression and decompression. These ASICs can partially or completely offload the computation from the host CPU. Instead of a complete implementation of an algorithm, only the API is required to use such an ASIC. The following APIs are also supported: DirectX Video Acceleration (DXVA2, Windows), Direct3D 11 (D3D11VA, Windows), Media Foundation (Windows), Vulkan (VKVA), VideoToolbox (iOS, iPadOS, macOS), RockChip MPP, OpenCL , OpenMAX , MMAL (Raspberry Pi), MediaCodec ( Android OS ), V4L2 (Linux). Depending on

414-408: A viable archival encoding and the U.S. Library of Congress began regarding it as a suitable option for preservation encoding in 2014. Compared to lossless JPEG 2000, FFV1 features comparable compression ratios and lower computing requirements. As of 2014, it is being used by archives, particularly where the collections do not feature extensive broadcast materials and instead consist of oral history and

460-402: Is a list of applications known to be able to read and/or write FFV1 video files, either natively or by installing codec packages. Entries marked with "-" means that they generally only support either encoding or decoding. The term "built-in" means that the application can handle FFV1 without the necessity to install additional codec packages. Applications that come with FFV1 support out of

506-433: Is a mix of pre-recorded and live presentations. Because virtual or hybrid events allow people from different time zones to participate simultaneously, some will have to participate during their night-time. Some virtual conferences try to mitigate this issue by alternating their schedule in a way so that everyone has the chance to participate at day time at least once. Prospective presenters are usually asked to submit

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552-446: Is also featured. The "Österreichische Mediathek" has also developed DVA-Profession a Free Software solution for archive-suitable mass video digitization, mainly using FFV1 as video encoding throughout the whole workflow, without transcoding. Additionally, they have initiated the development of "FFV1.3" (=version 3 of FFV1) together with Michael Niedermayer ( FFmpeg ), Peter Bubestinger-Steindl and Dave Rice; see #Versions below. Here

598-483: Is also listed as a format option for long-term preservation of moving images on sites of the U.S. Library of Congress ', State Records NSW and others. The Society of American Archivists has published a paper in August 2014, suggesting only FFV1 as preservation codec for video. The Digital Preservation project at the U.S. Library of Congress identified AVI and Matroska as common container formats for FFV1. Within

644-478: Is done as follows: The third value, Top + Left - TopLeft , is effectively equivalent to applying the "top" predictor to the current and the left sample, followed by applying the left predictor to the prediction residual of the top predictor. This method, also known as the gradient, exploits both horizontal and vertical redundancy. So in simple terms the prediction is the median of the top, left, and gradient prediction methods. For improved performance and simplicity,

690-484: Is no longer being actively developed, but still maintained. In summer 2010, FFmpeg developers Fiona Glaser, Ronald Bultje, and David Conrad, announced the ffvp8 decoder. Through testing, they determined that ffvp8 was faster than Google's own libvpx decoder. Starting with version 0.6, FFmpeg also supported WebM and VP8 . In October 2013, a native VP9 decoder and OpenHEVC, an open source High Efficiency Video Coding (HEVC) decoder, were added to FFmpeg. In 2016

736-535: Is part of the workflow of many other software projects, and its libraries are a core part of software media players such as VLC , and has been included in core processing for YouTube and Bilibili . Encoders and decoders for many audio and video file formats are included, making it highly useful for the transcoding of common and uncommon media files. FFmpeg is published under the LGPL-2.1-or-later or GPL-2.0-or-later , depending on which options are enabled. The project

782-638: Is sent to Earth. Academic conference#Organization An academic conference or scientific conference (also congress , symposium , workshop , or meeting ) is an event for researchers (not necessarily academics ) to present and discuss their scholarly work. Together with academic or scientific journals and preprint archives, conferences provide an important channel for exchange of information between researchers. Further benefits of participating in academic conferences include learning effects in terms of presentation skills and "academic habitus ", receiving feedback from peers for one's own research,

828-784: The European Union , for example. Patents for many older codecs, including AC3 and all MPEG-1 and MPEG-2 codecs, have expired. FFmpeg is licensed under the LGPL license, but if a particular build of FFmpeg is linked against any GPL libraries (notably x264 ), then the entire binary is licensed under the GPL. FFmpeg is used by software such as Blender , Cinelerra-GG Infinity , HandBrake , Kodi , MPC-HC , Plex , Shotcut , VirtualDub2 (a VirtualDub fork), VLC media player , xine and YouTube . It handles video and audio playback in Google Chrome and

874-564: The U.S. Library of Congress says: "[...] for video, there are many choices when it comes to codecs (the way the bits are encoded/decoded to represent the visual data, e.g., ffv1, H.264, Apple ProRes) [...]" In January 2013, the possible use and adoption of FFV1 as an archiving codec was addressed in the issue of PrestoCentre's AV Insider magazine: "FFV1 has many beneficial technical features [...], but adoption rates are relatively low compared with alternatives, for example JPEG2000. [...] But holding back too long only serves to self-perpetuate

920-461: The predatory publishing business model, which involves the creation of academic publications built around an exploitative business model that generally involves charging publication fees to authors without providing the editorial and publishing services associated with legitimate journals. BIT Life Sciences and SCIgen are some of the conferences labeled as predatory. Academic conferences are criticized for being environmentally unfriendly, due to

966-424: The sciences , presenters usually base their talk around a visual presentation that displays key figures and research results. A large meeting will usually be called a conference, while a smaller is termed a workshop. They might be single track or multiple track , where the former has only one session at a time, while a multiple track meeting has several parallel sessions with speakers in separate rooms speaking at

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1012-570: The CABAC Arithmetic coder from H.264, but due to the uncertain patent/royalty situation, as well as its slightly worse performance, CABAC was replaced by range coding. On April 16, 2006, a commit-message by Michael Niedermayer confirmed that the bitstream of FFV1 (version 1) is frozen: "ffv1 and ffvhuff haven't changed since a long time and no one proposed any changes within 1 month after my warning so they are officially no longer experimental and we will guarantee decodability of files encoded with

1058-627: The Linux version of Firefox. GUI front-ends for FFmpeg have been developed, including Multimedia Xpert and XMedia Recode. FFmpeg is used by ffdshow , FFmpegInterop, the GStreamer FFmpeg plug-in , LAV Filters and OpenMAX IL to expand the encoding and decoding capabilities of their respective multimedia platforms. As part of NASA 's Mars 2020 mission, FFmpeg is used by the Perseverance rover on Mars for image and video compression before footage

1104-711: The amount of airplane traffic generated by them. A correspondence on Nature.com points out the "paradox of needing to fly to conferences" despite increased calls for sustainability by environmental scientists. The academic community's carbon footprint is comprised in large parts by emissions caused by air travel. Few conferences enacted practices to reduce their environmental impact by 2017, despite guidelines being widely available: An analysis of academic conferences taking place in 2016 showed that only 4% of 116 conferences sampled offered carbon offset options and only 9% of these conferences implemented any form of action to their reduce environmental impact. More conferences included

1150-406: The box , usually use FFmpeg 's or Libav 's libraries in order to do so. The list is far from being complete, and will be augmented over time: FFV1 is not strictly an intra-frame format; despite not using inter-frame prediction, it allows the context model to adapt over multiple frames. This can be useful for compression due to the very large size of the context table, but can be disabled to force

1196-472: The codec-family index "31" in their combined list of video codec references. For long-term preservation of digital video sustainable container formats as well as audio/video codecs are necessary. There is no consensus as of 2013 among the archival community as to which file format or codecs should be used for preservation purposes for digital video. The previously proclaimed encodings were Motion JPEG 2000 (lossless) and uncompressed video. FFV1 proved to be

1242-516: The conference proceedings . Usually a conference will include keynote speakers (often, scholars of some standing, but sometimes individuals from outside academia). The keynote lecture is often longer, lasting sometimes up to an hour and a half, particularly if there are several keynote speakers on a panel . In addition to presentations, conferences also feature panel discussions , round tables on various issues, poster sessions and workshops. Some conferences take more interactive formats, such as

1288-513: The current ffv1/ffvhuff in the future" The current authoritative documentation was started in April 2012, and stayed in a very basic state until 2015. In 2015, as part of the IETF standardization process, the documentation is now improved and reviewed by the CELLAR working group in close cooperation with Michael Niedermayer. FFmpeg FFmpeg is a free and open-source software project consisting of

1334-552: The edges of the frame are assumed to be zero to avoid special cases. The prediction in encoding and decoding is managed using a ring buffer . The residuals are coded using either Golomb-Rice coding or range coding . Both options use a very large context model. The "small" context model uses (11×11×11+1)/2=666 contexts based on the neighboring values of ( Left − TopLeft ) , (TopLeft-Top) , and ( Top − TopRight ) . The "large" context model uses (11×11×5×5×5+1)/2=7563 contexts based on

1380-403: The encoder to generate a strictly intra-frame bitstream. As the gained compression seems to decrease with later versions of FFV1 (version 2,3), the use of GOP size greater than "1" might disappear in the future. During progressive scanning of a frame, the difference between a current pixel and its predicted value, judging by neighboring pixels, is sent to the entropy-coding process. The prediction

1426-622: The environment, these APIs may lead to specific ASICs, to GPGPU routines, or to SIMD CPU code. FFmpeg supports many common and some uncommon image formats. The PGMYUV image format is a homebrew variant of the binary (P5) PGM Netpbm format . FFmpeg also supports 16-bit depths of the PGM and PPM formats, and the binary (P7) PAM format with or without alpha channel, depth 8 bit or 16 bit for pix_fmts monob, gray, gray16be, rgb24, rgb48be, ya8, rgba, rgb64be . In addition to FFV1 and Snow formats, which were created and developed from within FFmpeg,

FFV1 - Misplaced Pages Continue

1472-519: The following filters. FFmpeg supports the following devices via external libraries. FFmpeg contains more than 100 codecs, most of which use compression techniques of one kind or another. Many such compression techniques may be subject to legal claims relating to software patents . Such claims may be enforceable in countries like the United States which have implemented software patents, but are considered unenforceable or void in member countries of

1518-658: The like. Since around 2015, the European PREFORMA Project started working on the standardisation of FFV1 through the Internet Engineering Task Force (IETF) . It was standardised in August 2021 as RFC 9043. The PERFORMA Project also implemented a conformance checker for FFV1 in the Matroska container. Details of FFV1's standardization plan have been prepared by MediaArea (authors of MediaInfo ) as part of their conformance checking tool "Media CONCH". It

1564-897: The native AAC encoder was considered stable, removing support for the two external AAC encoders from VisualOn and FAAC . FFmpeg 3.0 (nicknamed "Einstein" ) retained build support for the Fraunhofer FDK AAC encoder. Since version 3.4 "Cantor" FFmpeg supported the FITS image format. Since November 2018 in version 4.1 "al-Khwarizmi" AV1 can be muxed in MP4 and Matroska incl. WebM . FFmpeg encompasses software implementations of video and audio compressing and decompressing algorithms. These can be compiled and run on diverse instruction sets. Many widespread instruction sets are supported by FFmpeg, including x86 ( IA-32 and x86-64 ), PPC ( PowerPC ), ARM , DEC Alpha , SPARC , and MIPS . There are

1610-538: The participant driven " unconference " or various conversational formats. Academic conferences have been held in three general formats: in-person, virtual or online and hybrid (in-person and virtual). Conferences have traditionally been organized in-person. Since the COVID-19 pandemic many conferences have either temporarily or permanently switched to a virtual or hybrid format. Some virtual conferences involve both asynchronous and synchronous formats. For example, there

1656-457: The possibility to engage in informal communication with peers about work opportunities and collaborations, and getting an overview of current research in one or more disciplines . Conferences usually encompass various presentations . They tend to be short and concise, with a time span of about 10 to 30 minutes; presentations are usually followed by a discussion . The work may be bundled in written form as academic papers and published as

1702-418: The previous two years by means of fuzz testing . In January 2018, the ffserver command-line program – a long-time component of FFmpeg – was removed. The developers had previously deprecated the program citing high maintenance efforts due to its use of internal application programming interfaces . The project publishes a new release every three months on average. While release versions are available from

1748-489: The program. Business meetings for learned societies , interest groups , or affinity groups can also be part of the conference activities. Academic conferences typically fall into three categories: Increasing numbers of amplified conferences are being provided which exploit the potential of WiFi networks and mobile devices in order to enable remote participants to contribute to discussions and listen to ideas. Advanced technology for meeting with any yet unknown person in

1794-446: The project also supports the following formats: Output formats (container formats and other ways of creating output streams) in FFmpeg are called "muxers". FFmpeg supports, among others, the following: FFmpeg does not support IMC1-IMC4, AI44, CYMK, RGBE , Log RGB and other formats. It also does not yet support ARGB 1:5:5:5 , 2:10:10:10 , or other BMP bitfield formats that are not commonly used. FFmpeg supports, among others,

1840-507: The proprietary codecs from this list, only a few are left. [...] This basically leaves heritage institutions that want to use a lossless codec, with only two options: Jpeg2000 and FFV1." In 2015, the International Federation of Television Archives (FIAT/IFTA) mentioned FFV1 explicitly in their call-for-presentations for their annual World Conference , asking "Is FFV1 the new JPEG2000 "?. A workshop titled "FFV1 for Preservation"

1886-489: The same time. However, there are no commonly shared definitions even within disciplines for each event type. There might be no conceivable difference between a symposium, a congress or a conference. The larger the conference, the more likely it is that academic publishing houses may set up displays. Large conferences also may have a career and job search and interview activities. At some conferences, social or entertainment activities such as tours and receptions can be part of

FFV1 - Misplaced Pages Continue

1932-457: The same values as before, but also ( TopTop − Top ) and ( LeftLeft − Left ) , where TopTop is the pixel two above the current one vertically, and LeftLeft is the pixel two to the left of the current one. In range coding, each "context" actually has 32 sub-contexts used for various portions of coding each residual, resulting in a grand total of 242,016 contexts for the "large" model. Early experimental versions of FFV1 used

1978-652: The status of FFV1. The adoption by Archivematica and the Austrian Mediathek with their active promotion of FFV1 along with others may start to break this vicious circle. This could lead to a virtuous circle of wider take-up, to shared development, to incorporation into commercial products and a host of other benefits for the community." PACKED - the "Centre of Expertise in Digital Heritage" in Belgium, say in an article about video formats for archiving: "When removing

2024-844: The video archiving domain, the interest in FFV1 is increasing, as can be seen in a thread on the AMIA-L mailing list, the PrestoCentre Forum or the Archivematica mailing list. Companies are also picking up FFV1 support. For example, NOA (formerly "NOA Audio Solutions"), announced support for the FFV1 in their product line in July 2013 and KEM-Studiotechnik released a film-scanner with FFV1 output in November 2013. In an interview for The New York Times magazine about "Tips on Archiving Family History", Bertram Lyons from

2070-564: The website for download, FFmpeg developers recommend that users compile the software from source using the latest build from their source code Git version control system . Two video coding formats with corresponding codecs and one container format have been created within the FFmpeg project so far. The two video codecs are the lossless FFV1 , and the lossless and lossy Snow codec. Development of Snow has stalled, while its bit-stream format has not been finalized yet, making it experimental since 2011. The multimedia container format called NUT

2116-500: Was started by Fabrice Bellard (using the pseudonym "Gérard Lantau") in 2000, and was led by Michael Niedermayer from 2004 until 2015. Some FFmpeg developers were also part of the MPlayer project. The name of the project is inspired by the MPEG video standards group, together with "FF" for "fast forward", so FFmpeg stands for "Fast Forward Moving Picture Experts Group". The logo represents

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