|
Video Compression Format
A video coding format (or sometimes video compression format) is a content representation format 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 computer software or hardware component that compresses or decompresses a specific video coding format is 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. There are ''de facto'' standards and formal standards. Video content encoded using a particular video coding format is normally bundled with an audio stream (encoded using an audio coding format) inside a multimedia container format such as AVI, MP4, FLV, RealMedia, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Advanced Video Coding
Advanced Video Coding (AVC), also referred to as H.264 or MPEG-4 Part 10, is a video compression standard based on block-oriented, motion-compensated coding. It is by far the most commonly used format for the recording, compression, and distribution of video content, used by 84–86% of video industry developers . It supports a maximum resolution of 8K UHD. The intent of the H.264/AVC project was to create a standard capable of providing good video quality at substantially lower bit rates than previous standards (i.e., half or less the bit rate of MPEG-2, H.263, or MPEG-4 Part 2), without increasing the complexity of design so much that it would be impractical or excessively expensive to implement. This was achieved with features such as a reduced-complexity integer discrete cosine transform (integer DCT), variable block-size segmentation, and multi-picture inter-picture prediction. An additional goal was to provide enough flexibility to allow the standard to be applied ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Container Format (digital)
A container format (informally, sometimes called a wrapper) or metafile is a file format that allows multiple data streams to be embedded into a single computer file, file, usually along with metadata for identifying and further detailing those streams. Notable examples of container formats include archive files (such as the ZIP (file format), ZIP format) and formats used for multimedia playback (such as Matroska, MPEG-4 Part 14, MP4, and Audio Video Interleave, AVI). Among the earliest cross-platform container formats were Distinguished Encoding Rules and the 1985 Interchange File Format. Design Although containers may identify how data or metadata is encoded, they do not actually provide instructions about how to decode that data. A Computer program, program that can open a container must also use an appropriate codec to decode its contents. If the program doesn't have the required algorithm, it can't use the contained data. In these cases, programs usually emit an error mess ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C (programming Language)
C (''pronounced'' '' – like the letter c'') is a general-purpose programming language. It was created in the 1970s by Dennis Ritchie and remains very widely used and influential. By design, C's features cleanly reflect the capabilities of the targeted Central processing unit, CPUs. It has found lasting use in operating systems code (especially in Kernel (operating system), kernels), device drivers, and protocol stacks, but its use in application software has been decreasing. C is commonly used on computer architectures that range from the largest supercomputers to the smallest microcontrollers and embedded systems. A successor to the programming language B (programming language), B, C was originally developed at Bell Labs by Ritchie between 1972 and 1973 to construct utilities running on Unix. It was applied to re-implementing the kernel of the Unix operating system. During the 1980s, C gradually gained popularity. It has become one of the most widely used programming langu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OpenH264
OpenH264 is a free software library for real-time encoding and decoding video streams in the H.264/MPEG-4 AVC format. It is released under the terms of the Simplified BSD License." History Move to free-to-use binaries On October 30, 2013, Rowan Trollope from Cisco Systems announced that Cisco would release both binaries and source code of an H.264 video codec called OpenH264 under the Simplified BSD license, and pay all royalties for its use to MPEG LA themselves for any software projects that use Cisco's precompiled binaries (thus making Cisco's OpenH264 ''binaries'' free to use); any software projects that use Cisco's source code instead of its binaries would be legally responsible for paying all royalties to MPEG LA themselves, however. Current target CPU architectures are x86 and ARM, and current target operating systems are Linux, Windows XP and later, Mac OS X, Android and iOS. Although the source code for OpenH264 already existed in October 2013 and was used interna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Codec
A codec is a computer hardware or software component that encodes or decodes a data stream or signal. ''Codec'' is a portmanteau of coder/decoder. In electronic communications, an endec is a device that acts as both an encoder and a decoder on a signal or data stream, and hence is a type of codec. ''Endec'' is a portmanteau of encoder/decoder. A coder or encoder encodes a data stream or a signal for transmission or storage, possibly in encrypted form, and the decoder function reverses the encoding for playback or editing. Codecs are used in videoconferencing, streaming media, and video editing applications. History Originally, in the mid-20th century, a codec was a hardware device that coded analog signals into digital form using pulse-code modulation (PCM). Later, the term was also applied to software for converting between digital signal formats, including companding functions. Examples An audio codec converts analog audio signals into digital signals for transmissi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Firmware
In computing Computing is any goal-oriented activity requiring, benefiting from, or creating computer, computing machinery. It includes the study and experimentation of algorithmic processes, and the development of both computer hardware, hardware and softw ..., firmware is software that provides low-level control of computing device Computer hardware, hardware. For a relatively simple device, firmware may perform all control, monitoring and data manipulation functionality. For a more complex device, firmware may provide relatively low-level control as well as hardware abstraction Service (systems architecture), services to higher-level software such as an operating system. Firmware is found in a wide range of computing devices including personal computers, smartphones, home appliances, vehicles, computer peripherals and in many of the integrated circuits inside each of these larger systems. Firmware is stored in non-volatile memory either read-only memory (ROM) or progra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opus (audio Format)
Opus is a Lossy audio compression, lossy audio coding format developed by the Xiph.Org Foundation and standardized by the Internet Engineering Task Force, designed to efficiently speech coding, code speech and general audio in a single format, while remaining latency (audio), low-latency enough for real-time interactive communication and low-complexity enough for low-end embedded processors. Opus replaces both Vorbis and Speex for new applications. Opus combines the speech-oriented Linear predictive coding, LPC-based SILK algorithm and the lower-latency Modified discrete cosine transform, MDCT-based CELT algorithm, switching between or combining them as needed for maximal efficiency. Bitrate, audio bandwidth, complexity, and algorithm can all be adjusted seamlessly in each frame. Opus has the low algorithmic delay (26.5 ms by default) necessary for use as part of a real-time communication link, networked music performances, and live lip sync; by trading off quality or bitrat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vorbis
Vorbis is a free and open-source software project headed by the Xiph.Org Foundation. The project produces an audio coding format and software reference encoder/decoder ( codec) for lossy audio compression, libvorbis. Vorbis is most commonly used in conjunction with the Ogg container format and it is therefore often referred to as Ogg Vorbis. Version 1.0 of Vorbis was released in May 2000. Since 2013, the Xiph.Org Foundation has stated that the use of Vorbis should be deprecated in favor of the Opus codec, an improved and more efficient format that has also been developed by Xiph.Org. Name Vorbis is named after the character Exquisitor Vorbis in the '' Discworld'' novel '' Small Gods'' by Terry Pratchett. The Ogg format is named after ''ogging'', jargon from the computer game '' Netrek''. Development Vorbis is a continuation of audio compression development started in 1993 by Chris Montgomery. Intensive development began following a September 1998 letter from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WebM
WebM is an audiovisual media file format. It is primarily intended to offer a royalty-free alternative to use in the HTML video and the HTML audio elements. It has a sister project, WebP, for images. The development of the format is sponsored by Google, and the corresponding software is distributed under a BSD licenses, BSD license. The WebM Digital container format, container is based on a Profile (engineering), profile of Matroska. WebM initially supported VP8 video and Vorbis audio streams. In 2013, it was updated to accommodate VP9 video and Opus (audio format), Opus audio. It also supports the AV1 codec. Vendor support Software Native WebM support by Firefox, Mozilla Firefox, Opera (web browser), Opera, and Google Chrome was announced at the 2010 Google I/O conference. Internet Explorer 9 requires third-party WebM software. In 2021, Apple Inc., Apple released Safari (web browser), Safari 14.1 for macOS, which added native WebM support to the browser. , QuickTime does n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MPEG-2 Part 2
H.262 or MPEG-2 Part 2 (formally known as ITU-T Recommendation H.262 and ISO/IEC 13818-2, also known as MPEG-2 Video) is a video coding format standardised and jointly maintained by ITU-T Study Group 16 Video Coding Experts Group (VCEG) and ISO/ IEC Moving Picture Experts Group (MPEG), and developed with the involvement of many companies. It is the second part of the ISO/IEC MPEG-2 standard. The ITU-T Recommendation H.262 and ISO/IEC 13818-2 documents are identical. The standard is available for a fee from the ITU-T and ISO. MPEG-2 Video is very similar to MPEG-1, but also provides support for interlaced video (an encoding technique used in analog NTSC, PAL and SECAM television systems). MPEG-2 video is not optimized for low bit-rates (e.g., less than 1 Mbit/s), but somewhat outperforms MPEG-1 at higher bit rates (e.g., 3 Mbit/s and above), although not by a large margin unless the video is interlaced. All standards-conforming MPEG-2 Video decoders are also fully capab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Advanced Audio Coding
Advanced Audio Coding (AAC) is an audio coding standard for lossy digital audio compression. It was developed by Dolby, AT&T, Fraunhofer and Sony, originally as part of the MPEG-2 specification but later improved under MPEG-4.ISO (2006ISO/IEC 13818-7:2006 – Information technology — Generic coding of moving pictures and associated audio information — Part 7: Advanced Audio Coding (AAC), Retrieved on 2009-08-06ISO (2006, Retrieved on 2009-08-06 AAC was designed to be the successor of the MP3 format (MPEG-2 Audio Layer III) and generally achieves higher sound quality than MP3 at the same bit rate. AAC encoded audio files are typically packaged in an MP4 container most commonly using the filename extension .m4a. The basic profile of AAC (both MPEG-4 and MPEG-2) is called AAC-LC (''Low Complexity''). It is widely supported in the industry and has been adopted as the default or standard audio format on products including Apple's iTunes Store, Nintendo's Wii, DSi and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Video File
A video file format is a type of file format for storing digital video data on a computer system. Video is almost always stored using lossy compression to reduce the file size. A video file normally consists of a container (e.g. in the Matroska format) containing visual (video without audio) data in a video coding format (e.g. VP9) alongside audio data in an audio coding format (e.g. Opus). The container can also contain synchronization information, subtitles, and metadata such as title. A standardized (or in some cases de facto standard) video file type such as .webm is a profile specified by a restriction on which container format and which video and audio compression formats are allowed. The coded video and audio inside a video file container (i.e. not headers, footers, and metadata) is called the essence. A program (or hardware) which can decode compressed video or audio is called a codec; playing or encoding a video file will sometimes require the user to insta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
