The optical disk storage uses a laser to read on a magneto-optical material, which is non-volatility with good durability and high recording density. It is now used in computer systems as external storage. The contents of the storage unit can be freely taken out or stored as needed. Such a memory will lose its storage contents when the power is turned off, therefore, it mainly used to store programs for short-term use.

It is characterized by nonvolatile, that is, power loss then memory loss. There are two main types of RAM, one is called static RAM ( SRAM). SRAM is very fast, in other words, it is the fastest storage device for reading and writing, but it is also very expensive. So it is only used in demanding places, the primary buffer or secondary buffer of CPU, for example. DRAM keeps data for a short time and slower than SRAM, but it is faster than any ROM, but DRAM is cheaper than SRAM in terms of price. SRAM (static random access memory) does not need to be refreshed when power is applied, that is, data will not lost, and is generally not multiplexed with row and column addresses. DRAM (dynamic random access memory) requires constant refresh to save data. Moreover, its row and column addresses are multiplexed, and many have page mode. ROM usually refers to solidified computer memory (write once, read repeatedly), which is opposite to the RAM. Finally, from the drop down View box, select Final Result to see your final key.PROM is a programmable ROM, but it can be programmed once only, that is, after the software is written, it cannot be modified.There will be a thin gray outline around your subject (which is okay).

Decrease the Clip White until the subject is completely white.

Twirl the triangle next to Screen Matte and increase the Clip Black until your background is solid black.

We want the subject to be white and the background to be black. Black is transparent, white is opaque, and gray is in-between. You will now see what is transparent and what is opaque in your footage.

Then click on the little box that says Final Result and choose Status.

Then click on the footage where the color you wish to key out is the most prominent.

Now, in the Effect Controls window on the left of your screen, where it says Screen Colour, click on the little eye dropper.

Apply this effect to your footage by clicking, holding, and dragging this effect over the footage in the composition window.

In the effects panel search for the effect Keylight (1.2), which is under Keying.

Bring in your footage to a new composition.

This works with any color, but a properly lit green or blue screen will yield the best results. In this article, we will discuss how to chroma key out a background from your video.

Keylight 1.2 tutorial