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X264
x264 is a free and open-source software library and a command-line utility developed by VideoLAN for encoding video streams into the H.264/MPEG-4 AVC video coding format. It is released under the terms of the GNU General Public License. History x264 was originally developed by Laurent Aimar, who stopped development in 2004 after being hired by ATEME. Loren Merritt then took over development. Later, in 2008, Fiona Glaser joined the project. They both stopped contributing in 2014. Today, x264 is primarily developed by Anton Mitrofanov and Henrik Gramner. Capabilities x264 provides a command line interface as well as an API. The former is used by many graphical user interfaces, such as Staxrip and MeGUI. The latter is used by many other interfaces, such as HandBrake and FFmpeg. x264 implements a large number of features compared to other H.264 encoders. x264 contains some psychovisual enhancements which aim to increase the subjective video quality of the encoded video. * Adapt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variance Adaptive Quantization
Variance Adaptive Quantization (VAQ) is a video encoding algorithm that was first introduced in the open source video encoder x264. According to Xvid Builds FAQ: "It's an algorithm that tries to optimally choose a quantizer for each macroblock using advanced math algorithms." It was later ported to programs which encode video content in other video standards, like MPEG-4 ASP or MPEG-2. In the case of Xvid Xvid (formerly "XviD") is a video codec library following the MPEG-4 video coding standard, specifically MPEG-4 Part 2 Advanced Simple Profile (ASP). It uses ASP features such as b-frames, global and quarter pixel motion compensation, lumi mas ..., the algorithm is intended to make up for the earlier limitations in its Adaptive Quantization mode. The first Xvid library containing this improvement was released in February 2008. References External links Implementation of variance-based adaptive quantization in x264 {{Tv-tech-stub Signal processing Video compression ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FFmpeg
FFmpeg is a free and open-source software project consisting of 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 of 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, 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 is part of the workflow of many other software projects, and its libraries are a core part of software media players such as VLC, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Assembly Language
In computer programming, assembly language (or assembler language, or symbolic machine code), often referred to simply as Assembly and commonly abbreviated as ASM or asm, is any low-level programming language with a very strong correspondence between the instructions in the language and the architecture's machine code instructions. Assembly language usually has one statement per machine instruction (1:1), but constants, comments, assembler directives, symbolic labels of, e.g., memory locations, registers, and macros are generally also supported. The first assembly code in which a language is used to represent machine code instructions is found in Kathleen and Andrew Donald Booth's 1947 work, ''Coding for A.R.C.''. Assembly code is converted into executable machine code by a utility program referred to as an '' assembler''. The term "assembler" is generally attributed to Wilkes, Wheeler and Gill in their 1951 book '' The Preparation of Programs for an Electronic Di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sum Of Absolute Transformed Differences
The sum of absolute transformed differences (SATD) is a block matching criterion widely used in fractional motion estimation for video compression. It works by taking a frequency transform, usually a Hadamard transform, of the differences between the pixels in the original block and the corresponding pixels in the block being used for comparison. The transform itself is often of a small block rather than the entire macroblock. For example, in x264, a series of 4×4 blocks are transformed rather than doing the more processor-intensive 16×16 transform. Comparison to other metrics SATD is slower than the sum of absolute differences (SAD), both due to its increased complexity and the fact that SAD-specific MMX and SSE2 instructions exist, while there are no such instructions for SATD. However, SATD can still be optimized considerably with SIMD instructions on most modern CPUs. The benefit of SATD is that it more accurately models the number of bits required to transmit the re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VideoLAN
VideoLAN is a non-profit organization which develops software for playing video and other media formats. It originally developed two programs for media streaming, VideoLAN Client (VLC) and VideoLAN Server (VLS), but most of the features of VLS have been incorporated into VLC, with the result renamed VLC media player. The VideoLAN project began as a student endeavor at École Centrale Paris (France), but after releasing the software under the free software/open source GNU General Public License, the project is now multinational with a development team spanning 40 nations. The project has been completely separated from École Centrale Paris since 2009 when it was constituted as a non-profit organization. The current President of the VideoLAN non-profit organization is Jean-Baptiste Kempf, who is also one of the project's developers. Projects VLC VLC (standing for VideoLAN Client) is a portable multimedia player, encoder, and streamer supporting many audio and video codecs an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rate–distortion Optimization
Rate-distortion optimization (RDO) is a method of improving video quality in video compression. The name refers to the optimization of the amount of ''distortion'' (loss of video quality) against the amount of data required to encode the video, the ''rate''. While it is primarily used by video encoders, rate-distortion optimization can be used to improve quality in any encoding situation (image, video, audio, or otherwise) where decisions have to be made that affect both file size and quality simultaneously. Background The classical method of making encoding decisions is for the video encoder to choose the result which yields the highest quality output image. However, this has the disadvantage that the choice it makes might require more bits while giving comparatively little quality benefit. One common example of this problem is in motion estimation, and in particular regarding the use of quarter pixel-precision motion estimation. Adding the extra precision to the motion of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Video Coding Format
A video coding format (or sometimes video compression format) is a content representation format for storage or transmission of digital video content (such as in a data file or bitstream). It typically uses a standardized video compression algorithm, most commonly based on discrete cosine transform (DCT) coding and motion compensation. A specific software, firmware, or hardware implementation capable of compression or decompression to/from a specific video coding format is called a video codec. Some video coding formats are documented by a detailed technical specification document known as a video coding specification. Some such specifications are written and approved by standardization organizations as technical standards, and are thus known as a video coding standard. The term 'standard' is also sometimes used for ''de facto'' standards as well as formal standards. Video content encoded using a particular video coding format is normally bundled with an audio stream (encoded ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Media Player
A digital media player (also sometimes known as a streaming device or streaming box) is a type of consumer electronics device designed for the storage, playback, or viewing of digital media content. They are typically designed to be integrated into a home cinema configuration, and attached to a television and/or AV receiver. The term is most synonymous with devices designed primarily for the consumption of content from streaming media services such as internet video, including subscription-based over-the-top content services. These devices usually have a compact form factor (either as a compact set-top box, or a dongle designed to plug into an HDMI port), and contain a 10-foot user interface with support for a remote control and, in some cases, voice commands, as control schemes. Some services may support remote control on digital media players using their respective mobile apps, while Google's Chromecast ecosystem is designed around integration with the mobile apps of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Warner Bros
Warner Bros. Entertainment Inc. (commonly known as Warner Bros. or abbreviated as WB) is an American film and entertainment studio headquartered at the Warner Bros. Studios complex in Burbank, California, and a subsidiary of Warner Bros. Discovery. Founded in 1923 by four brothers, Harry, Albert, Sam, and Jack Warner, the company established itself as a leader in the American film industry before diversifying into animation, television, and video games and is one of the "Big Five" major American film studios, as well as a member of the Motion Picture Association (MPA). The company is known for its film studio division the Warner Bros. Pictures Group, which includes Warner Bros. Pictures, New Line Cinema, the Warner Animation Group, Castle Rock Entertainment, and DC Studios. Among its other assets, stands the television production company Warner Bros. Television Studios. Bugs Bunny, a cartoon character created by Tex Avery, Ben Hardaway, Chuck Jones, Bob Givens and Robe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ARM Architecture
ARM (stylised in lowercase as arm, formerly an acronym for Advanced RISC Machines and originally Acorn RISC Machine) is a family of reduced instruction set computer (RISC) instruction set architectures for computer processors, configured for various environments. Arm Ltd. develops the architectures and licenses them to other companies, who design their own products that implement one or more of those architectures, including system on a chip (SoC) and system on module (SOM) designs, that incorporate different components such as memory, interfaces, and radios. It also designs cores that implement these instruction set architectures and licenses these designs to many companies that incorporate those core designs into their own products. There have been several generations of the ARM design. The original ARM1 used a 32-bit internal structure but had a 26-bit address space that limited it to 64 MB of main memory. This limitation was removed in the ARMv3 series, which h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
