Introduction
Type of subscriber end devices are increasing according to demand and comfort of subscribers like Smartphones ,Tablets , 4K STBs and Android Tv etc. To fulfill all the requirements compression algorithm are improving by implementing new ideas of saving more information in frames etc.
So in this articles we will cover What Is AVC , How does it work and Supported Browsers for it.
What Is AVC
AVC stands for Advanced Video Coding. It is also known as H.264 or MPRG 4 Part 10. AVC is most widely used compression standard introduced by MPEG and ITU-T. It is the successor of MPEG 2 and MPEG 4 visual. It provides the same quality with lower bitrate in compare with its predecessors like H.263 and MPEG 2. It reduces the bandwidth near about 50 percent by providing same quality of its previous version.
H.264 is highly adopted for its better compression techniques that is why today its running in more than 1 billion devices. It is adopted by small resolution devices like mobiles and tablets as well as with Standard Definition videos and High Definition Video content. Technical giants uses H.264 video codec today like Apple and Microsoft etc. It is adopted in streaming media for example YouTube and Vimeo etc.
Working Of AVC or H.264
As shown above in the figure there is a professional lady. We are considering here a frame only. Now this frame is divided by linings into small “Chunks“. These chunks are known as “MacroBlocks“. There are various size of MacroBlocks in this frame. But the maximum size of one MacroBlock is 16*16 pixel. This is the property of Advance Video Coding algorithm.
Intra-Frame Compression
In intra-frame compression AVC compression algorithm consider only one frame. As shown above in the figure of professional lady. This frame is divided into MacroBlocks upto 16*16 pixels. But you can see background color of this frame is white only from top to bottom of image.
So at the time of AVC encoding instead of capturing the whole white MacroBlocks in background, it capture only one white MacroBlock and repeat it in whole background color. By doing so we need not to capture the whole number of white MacroBlocks of background so lesser is the capturing information lower is the bitrate of data. Thus our encoded data is saved which enable us to send this data at lower bitrate by maintaining same quality of data.. This is the working of Intra-frame compression.
Inter-Frame Compression
When there are more than one frame is considered then Inter-Frame Compression take place. In other words it is the comparison between two or more than two frames.
As shown above in the figure we considered only one frame. But in capturing the video there will be more frames. So suppose this professional lady is speaking something. In the next frames its lips and body will move only while background is still the same.
So this encoding algorithm will capture only moving part of frames or moving information of next frame only. While rest information it will copy into the next frames. This depends on the lady how long she is speaking sometimes this information is repeated in next 100 frames or can be more than it. So it save lots of information which enable us to send this information in lower bitrate.
In other words we can say repeated information is captured once only and discarded for next frames which reduces the amount of data by maintaining the same quality.
Advanced Video Coding algorithm uses 9 Intra-Prediction Direction means it gives potential reference to pixel blocks in 9 different directions. Which enable it to compress the frame more efficiently.
AVC Supported Browsers
Chrome 4+ Version
Internet Explorer 9+ Version
Safari 3.2+ Version
Firefox Partial Support 2.1+
Conclusion
Advanced Video Coding is widely adopted and efficient compression standard introduced by MPEG and ITU-T. It is upgraded version of H.263 and it is also known as H.264. It provides same quality by reducing its bandwidth near about 50 %. It requires a bit more computational power than its previous versions. It is highly adopted in streaming media like YouTube and Vimeo etc.
Know More About What Is HEVC H.265
