About compression keyframes

Compression keyframes are different from the keyframes placed in the Premiere Timeline window. Compression keyframes are automatically placed during export at regular intervals in the movie. During compression, they are stored as complete frames. The frames between the keyframes, called intermediate frames, are compared to the previous frame and only the changed data is stored. This process can greatly reduce file size, depending on the spacing of the keyframes. Fewer keyframes and more intermediate frames result in smaller file sizes, but produce lower-quality images and playback. More keyframes and fewer intermediate frames result in significantly larger file sizes, but produce higher-quality images and playback.

Choosing compression settings is a balancing act that varies depending on the type of video material, the target delivery format, and the intended audience. Often, the optimal compression setting is arrived at through trial and error.

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