Which frame type uses both earlier and later frames for predictive image construction?

The B-Frame (bidirectional frame) is distinct in its function because it utilizes both earlier and later frames to predict and construct the current image. This allows for more efficient compression, as B-Frames take advantage of temporal redundancy by referencing data from both directions in the video sequence.

In the context of video coding, B-Frames can leverage the differences and similarities found in both preceding and subsequent frames. This type of frame is particularly effective in reducing the overall file size of a video while maintaining a high level of image quality, as it can achieve better data compression ratios by exploiting bidirectional motion.

P-Frames, unlike B-Frames, utilize only previous frames for their predictive construction, which makes them less efficient in certain scenarios where there is motion between frames. I-Frames (intra-coded frames) are independent and do not rely on any other frames for their data, making them crucial for scene changes or as reference points in the coding sequence, but they do not utilize predictive methods based on other frames.

Therefore, the B-Frame's capacity to use both prior and subsequent frames enhances its role in video encoding, making it an integral part of many video compression standards like H.264.