|
AMV Video Format
AMV (Actions Media Video) is a proprietary video file format designed for portable media players (often marketed as "MP4 players"), as well as S1 MP3 players with video playback. There are two different versions of this format: an older one for Actions chips, and a newer one for ALi's M5661 chip, sometimes called ALIAVI. Format The container is a modified version of AVI. The video format is a variant of Motion JPEG, with fixed rather than variable quantisation tables. The audio format is a variant of IMA ADPCM, where the first 8 bytes of each frame are origin (16 bits), index (16 bits) and number of encoded 16-bit samples (32 bits); all known AMV files run sound at 22050 samples/second. Low decoder overhead is paramount as the S1 MP3 players have very low-end processors (a Z80 variant). Video compression ratio is low – around 4 pixels/byte, compared with over 10 pixels/byte for MPEG-2 – though as the files are of low resolution (96×96 up to 208×176) and frame rate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Audio Video Interleave
Audio Video Interleave (also Audio Video Interleaved and known by its initials and filename extension AVI, usually pronounced ) is a proprietary multimedia container format and Windows standard introduced by Microsoft in November 1992 as part of its Video for Windows software. AVI files can contain both audio and video data in an uncompressed file container that allows synchronous audio-with-video playback. Like the DVD video format, AVI files support multiple streaming audio and video, although these features are seldom used. Codecs popularly used for AVI include DivX and Xvid, although many other codecs can also be contained in an AVI file. Many AVI files use the file format extensions developed by the Matrox OpenDML group in February 1996. These files are supported by Microsoft, and are unofficially called AVI 2.0. In 2010 the US government's National Archives and Records Administration defined AVI as the official wrapper for preserving digital video. History ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADPCM
Adaptive differential pulse-code modulation (ADPCM) is a variant of differential pulse-code modulation (DPCM) that varies the size of the quantization step, to allow further reduction of the required data bandwidth for a given signal-to-noise ratio. Typically, the adaptation to signal statistics in ADPCM consists simply of an adaptive scale factor before quantizing the difference in the DPCM encoder. ADPCM was developed for speech coding by P. Cummiskey, Nikil S. Jayant and James L. Flanagan at Bell Labs in 1973. In telephony In telephony, a standard audio signal for a single phone call is encoded as 8000 analog samples per second, of 8 bits each, giving a 64 kbit/s digital signal known as DS0. The default signal compression encoding on a DS0 is either μ-law (mu-law) PCM (North America and Japan) or A-law PCM (Europe and most of the rest of the world). These are logarithmic compression systems where a 13- or 14-bit linear PCM sample number is mapped into an 8-bit value ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Google Code
Google Developers (previously Google Code) , application programming interfaces (APIs), and technical resources. The site contains documentation on using Google developer tools and APIs—including discussion groups and blogs for developers using Google's developer products. There are APIs offered for almost all of Google's popular consumer products, like Google Maps, YouTube, Google Apps, and others. The site also features a variety of developer products and tools built specifically for developers. Google App Engine is a hosting service for web apps. Project Hosting gives users version control for open source code. Google Web Toolkit (GWT) allows developers to create Ajax applications in the Java programming language.(All languages) The site contains reference information for community based developer products that Google is involved with like Android from the Open Handset Alliance and OpenSocial from the OpenSocial Foundation. Google APIs Google offers a variety of API ... [...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 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 V ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reverse Engineering
Reverse engineering (also known as backwards engineering or back engineering) is a process or method through which one attempts to understand through deductive reasoning how a previously made device, process, system, or piece of software accomplishes a task with very little (if any) insight into exactly how it does so. Depending on the system under consideration and the technologies employed, the knowledge gained during reverse engineering can help with repurposing obsolete objects, doing security analysis, or learning how something works. Although the process is specific to the object on which it is being performed, all reverse engineering processes consist of three basic steps: information extraction, modeling, and review. Information extraction is the practice of gathering all relevant information for performing the operation. Modeling is the practice of combining the gathered information into an abstract model, which can be used as a guide for designing the new object or syst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frame Rate
Frame rate, most commonly expressed in frame/s, or FPS, is typically the frequency (rate) at which consecutive images (Film frame, frames) are captured or displayed. This definition applies to film and video cameras, computer animation, and motion capture systems. In these contexts, frame rate may be used interchangeably with and refresh rate, which are expressed in hertz. Additionally, in the context of computer graphics performance, FPS is the rate at which a system, particularly a GPU, is able to generate frames, and refresh rate is the frequency at which a display shows completed frames. In electronic camera specifications frame rate refers to the maximum possible rate frames could be captured, but in practice, other settings (such as exposure time) may reduce the actual frequency to a lower number than the frame rate. Human vision The temporal sensitivity and resolution of human vision varies depending on the type and characteristics of visual stimulus, and it differs betw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MPEG-2
MPEG-2 (a.k.a. H.222/H.262 as was defined by the ITU) is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods, which permit storage and transmission of movies using currently available storage media and transmission bandwidth. While MPEG-2 is not as efficient as newer standards such as H.264/AVC and H.265/HEVC, backwards compatibility with existing hardware and software means it is still widely used, for example in over-the-air digital television broadcasting and in the DVD-Video standard. Main characteristics MPEG-2 is widely used as the format of digital television signals that are broadcast by terrestrial (over-the-air), cable, and direct broadcast satellite TV systems. It also specifies the format of movies and other programs that are distributed on DVD and similar discs. TV stations, TV receivers, DVD players, and other equipment are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zilog Z80
The Zilog Z80 is an 8-bit computing, 8-bit microprocessor designed by Zilog that played an important role in the evolution of early personal computing. Launched in 1976, it was designed to be Backward compatibility, software-compatible with the Intel 8080, offering a compelling alternative due to its better Integrated circuit, integration and increased performance. Along with the 8080's seven Processor register, registers and flags register, the Z80 introduced an alternate register set, two 16-bit index registers, and additional instructions, including bit manipulation and block copy/search. Originally intended for use in embedded systems like the 8080, the Z80's combination of compatibility, affordability, and superior performance led to widespread adoption in video game systems and home computers throughout the late 1970s and early 1980s, helping to fuel the personal computing revolution. The Z80 was used in iconic products such as the Osborne 1, TRS-80, Radio Shack TRS-80, Col ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interactive Multimedia Association
The Interactive Multimedia Association (IMA) was an industry association which developed a set of audio algorithms. The most important is the ADPCM algorithm which is in use by Apple and Microsoft Microsoft Corporation is an American multinational corporation and technology company, technology conglomerate headquartered in Redmond, Washington. Founded in 1975, the company became influential in the History of personal computers#The ear .... The Interactive Multimedia Association ceased operations around 1998. An archived copy of the document IMA Recommended Practices for Enhancing Digital Audio Compatibility in Multimedia Systems (version 3.0), which describes the IMA ADPCM algorithm, is available. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motion JPEG
Motion JPEG (M-JPEG or MJPEG) is a video compression format in which each video frame or interlaced field of a digital video sequence is compressed separately as a JPEG image. Originally developed for multimedia PC applications, Motion JPEG enjoys broad client support: most major web browsers and players provide native support, and plug-ins are available for the rest. Software and devices using the M-JPEG standard include media players, game consoles, digital cameras, IP cameras, webcams, streaming servers, video cameras, and non-linear video editors. History Motion JPEG was originally developed for multimedia PC applications. Early implementations of MJPEG were generally implemented in Hardware. C-Cube was an early proponent with their CL550 JPEG codec been used in several hardware implementations. It was announced that the NeXTdimension from NeXT would ship with an onboard CL550 to implement MJPEG. This was however later shelved and wasn't included in the final product ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantization (image Processing)
Quantization, involved in image processing, is a lossy compression technique achieved by compressing a range of values to a single quantum (discrete) value. When the number of discrete symbols in a given stream is reduced, the stream becomes more compressible. For example, reducing the number of colors required to represent a digital image makes it possible to reduce its file size. Specific applications include DCT data quantization in JPEG and DWT data quantization in JPEG 2000. Color quantization Color quantization reduces the number of colors used in an image; this is important for displaying images on devices that support a limited number of colors and for efficiently compressing certain kinds of images. Most bitmap editors and many operating systems have built-in support for color quantization. Popular modern color quantization algorithms include the nearest color algorithm (for fixed palettes), the median cut algorithm, and an algorithm based on octrees. It is common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acer Laboratories Incorporated
ALi Corporation (formerly Acer Laboratories Incorporated or Acer Labs Inc., and commonly known as ALi) is a major designer and manufacturer of Embedded system, embedded systems Integrated circuit, integrated circuits, and a former manufacturer of personal computer integrated circuits. It is based in Taiwan, and is a subsidiary of the Acer (company), Acer group. The company was founded in 1987, its president is Teddy Lu. Part of ALi including the personal computer integrated circuits business was spun off as ULi Electronics Inc. in June 2003. ULi was acquired by Nvidia in 2006 for $52 million. Products Chipsets 80X86 Chipsets Pentium and Socket 7 Chipsets Slot 1 and Socket 370 Chipsets Slot A and Socket A Chipsets Socket 478 Chipsets Socket 754/Socket 939, 939/Socket 940, 940 Chipsets Southbridge Chips Gigabyte GA-5AX rev. 3.0 20081118.jpg, ALi M1541-based motherboard with AMD K6-2 300 MHz processor Ali M1535.jpg, ALi M1535 Southbridge (computing), southbridge c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
