Video quality by controlling inter frame encoding according to frame position in GOP

摘要

In some embodiments, a video encoding method includes controlling a set of block encoding modes in a plurality of inter video frames in a group of pictures (GOP) according to a frame position in the group of pictures, to generally decrease a forward inter-encoded frame content with the frame position in the group of pictures. An encoding mode determination is made for inter-frame encoding blocks (e.g. macroblocks) according to the frame position in the group of pictures. The determination may include forcing a block encoding mode to an intra, backward inter-predicted, or backward strong-weighted bi-predicted mode. The determination may be performed according to a frame type (P/B), frame position in GOP, frame content, a selected temporal and spatial pattern, a bit cost of making an encoding mode decision, and an available bit rate. The fraction of mode-forced blocks is generally increased as the GOP frame position advances.

主权项

1. A video data encoding method for encoding a plurality of inter video frames, each frame comprising a plurality of non-overlapping blocks, in a group of pictures; said method comprising:
determining blocks eligible for mode-forcing in each of the plurality of inter video frames in the group of pictures; selecting a set of block encoding modes for the blocks eligible for mode-forcing, wherein a calculated or estimated rate cost of mode-forcing is within a pre-determined budget for the eligible blocks, wherein the rate cost is determined from a mode forcing fraction for bit processing applied to a prior frame of mode-forced blocks; controlling the set of block encoding modes within a video encoder for the blocks eligible for mode-forcing according to a frame position in the group of pictures, independent of content within the blocks, wherein a fraction of blocks within each frame is forced to a forward inter-encoded frame content, such that the fraction of forward inter-encoded blocks within each frame decreases as the frame position advances in the group of pictures; and encoding the plurality of inter frames according to the set of block encoding modes within the video encoder.