![]() ![]() Deblocking Filtering:ĭeblocking filtering is used to reduce the blocking artifacts that can occur in compressed video. The predicted values are then subtracted from the actual values to obtain the residual, which is then compressed using the same techniques used for intra-frame coding. Spatial prediction uses neighboring pixels to predict the value of the current pixel, while temporal prediction uses the previously-encoded frames to predict the value of the current frame. Spatial and temporal prediction are used to further reduce redundancy in the video. The motion vectors are then encoded and transmitted along with the residual data. It works by comparing the current frame to a reference frame and estimating the motion of each macroblock. Motion estimation and compensation is used to track the movement of objects in the video and reduce the amount of data that needs to be stored or transmitted. The difference between the predicted frame and the actual frame, known as the prediction error or residual, is then compressed using the same techniques used for intra-frame coding.ĪVC uses several inter-frame coding techniques, including motion estimation and compensation, spatial and temporal prediction, and deblocking filtering. It exploits temporal redundancy by using the information from previously-encoded frames to predict the contents of the current frame. ![]() Inter-frame coding is used to compress the differences between frames. The entropy coding is based on the statistical properties of the coefficients and assigns shorter codes to more probable values and longer codes to less probable values. The quantized transform coefficients are then entropy coded using a variable-length coding (VLC) scheme to further reduce the amount of data. The quantization process introduces some loss of information, but the amount of loss can be controlled by adjusting the quantization parameter. These transform blocks are transformed using a mathematical algorithm called the discrete cosine transform (DCT) to reduce spatial redundancy.Īfter the DCT, the resulting transform coefficients are quantized to further reduce the amount of data that needs to be stored or transmitted. Each frame is divided into a number of macroblocks, which are further divided into smaller blocks called transform blocks. Intra-frame coding is used to compress individual frames of video. It uses a combination of intra-frame and inter-frame coding to reduce redundancy and achieve high compression ratios. Technical Specifications:ĪVC is a block-based video compression standard that uses a variety of techniques to achieve high compression efficiency while maintaining high video quality. In 2004, Apple added support for AVC in QuickTime 7, which helped to further increase its popularity. ![]() It quickly gained popularity and became the most widely-used video codec in the world. The JVT included experts from both organizations and was responsible for developing the technical specifications for what would become AVC.Īfter several years of development, the first version of AVC was released in 2003. In 2001, the ITU-T Video Coding Experts Group (VCEG) and the ISO/IEC Moving Picture Experts Group (MPEG) formed a joint team, known as the Joint Video Team (JVT), to develop a new video compression standard. The goal was to develop a standard that could deliver high-quality video at low bitrates while also being flexible enough to support a wide range of applications and devices. The development of AVC began in the late 1990s when the need for a more efficient video compression standard was recognized. This article provides a detailed explanation of AVC, including its history, technical specifications, and applications. It provides significant improvements over its predecessors, such as MPEG-2 and MPEG-4 Part 2, in terms of video quality, compression efficiency, and flexibility. AVC was first introduced in 2003 by the Joint Video Team (JVT), a collaborative effort between the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC).ĪVC was designed to deliver high-quality video at low bitrates, making it ideal for use in a variety of applications, including mobile devices, video conferencing, and surveillance systems. The AVC (Advanced Video Codec), also known as H.264 or MPEG-4 Part 10, is a widely-used video compression standard that is currently the most commonly-used video codec for streaming, Blu-ray discs, and digital television broadcasting. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |