From the course: Premiere Pro Guru: Compositing and Masks

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Two types of alpha channels: Straight and premultiplied

Two types of alpha channels: Straight and premultiplied - Premiere Pro Tutorial

From the course: Premiere Pro Guru: Compositing and Masks

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Two types of alpha channels: Straight and premultiplied

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- Straight and pre-multiplied alpha channels are two different methods of encoding transparency information shown in an image or video. They are used to represent how transparent each pixel is and determine how that transparent elements interact with the background. Let's explore each type. Let's go ahead and open the sequence named 1.2, two types of alpha channels straight and pre-multiplied. The first set of clips represents the straight alpha channel. In a straight alpha channel, the transparency values are stored independently from the color values of the pixel. This means that it doesn't affect the color values of the pixels. Pre-multiplied channels store transparency information by blending the color values of each one of the pixels with the transparency value. In other words, the color values are pre-multiplied by the alpha value. The second set of clips represents pre-multiplied alpha channels pre-multiplied…

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