Dynamically determining group of picture size during encoding of video sequence

A method for encoding a sequence of video frames, said method comprising:

• (a) encoding the sequence of video frames to produce an encoded bitstream;
• (b) during said encoding (a), dynamically determining, as a function of frame variation between a frame and a reference frame within the sequence of video frames, a group of picture (GOP) length for at least one GOP of the encoded bitstream;
• and
• wherein said dynamically determining (b) comprises determining said GOP length by directing said encoding (a) to encode a frame of the sequence of video frames as an I frame, said I frame comprising said reference frame, and to encode subsequent frames of the sequence of video frames using motion estimation based on said I frame, and wherein said dynamically determining (b) further comprises beginning a new GOP when an encoded frame of said subsequent frames has a predefined picture degradation compared with said I frame.

A system for encoding a sequence of video frames, said system comprising:

• an encoder coupled to receive the sequence of video frames, said encoder producing therefrom an encoded bitstream;
• means coupled to said encoder for dynamically determining, as a function of frame variation between a frame and a reference frame within the sequence of video frames, a group of picture (GOP) length for at least one GOP of the encoded bitstream produced by said encoder;
• wherein said encoder comprises means for encoding a frame of the sequence of video frames as an intra-coded (I) frame and means for employing forward prediction motion estimation based on said encoded I frame for each frame of a variable number of frames temporally subsequent to said I frame, said I frame and said variable number of frames temporally subsequent thereto comprising said GOP length of said at least one GOP, and wherein said means for dynamically determining comprises means for dynamically determining said variable number of frames temporally subsequent to said I frame to be encoded employing forward prediction motion estimation based on said encoded I frame, said encoded I frame comprising said reference frame;
• and
• wherein said encoder comprises means for encoding each frame of said variable number of frames temporally subsequent to said I frame as a B frame, and wherein said GOP length comprises said encoded I frame and said variable number of encoded B frames only.

A system for encoding a sequence of video frames, said system comprising:

• an encoder coupled to receive the sequence of video frames, said encoder producing therefrom an encoded bitstream;
• means coupled to said encoder for dynamically determining, as a function of frame variation between a frame and a reference frame within the sequence of video frames, a group of picture (GOP) length for at least one GOP of the encoded bitstream produced by said encoder;
• and
• wherein said means for dynamically determining comprises means for determining said GOP length by directing said encoder to encode a frame of the sequence of video frames as an I frame, said I frame comprising said reference frame, and to encode subsequent frames of the sequence of video frames using motion estimation based on said I frame, and wherein said means for dynamically determining further comprises means for beginning a new GOP when an encoded frame of the subsequent frames has a predefined picture degradation compared with said I frame.

An article of manufacture, comprising:

• a computer usable medium having a computer-readable program code means embodied therein for causing a computer to affect encoding of a sequence of video frames, the computer-readable program code means in said article of manufacture comprising:
• computer-readable program code means for causing a computer to affect encoding the sequence of video frames to produce an encoded bitstream;
• computer-readable program code means for causing a computer to affect dynamically determining, as a function of frame variation between a frame and a reference frame within the sequence of video frames, a group of picture (GOP) length for at least one GOP of the encoded bitstream, said dynamically determining occurring during said encoding;
• wherein said computer-readable program code means for causing a computer to affect encoding comprises computer-readable program code means for causing a computer to affect encoding a frame of the sequence of video frames as an intra-coded (I) frame and employing forward prediction motion estimation based on said encoded I frame for each frame of a variable number of frames temporally subsequent to said encoded I frame, said I frame and said variable number of frames temporally subsequent thereto comprising said GOP length of said at least one GOP, and wherein said computer-readable program code means for causing a computer to affect dynamically determining comprises computer-readable program code means for causing a computer to affect dynamically determining said variable number of frames temporally subsequent to said I frame to be encoded employing forward prediction motion estimation based on said encoded I frame, said encoded I frame comprising said reference frame;
• and
• wherein said computer-readable program code means for causing a computer to affect encoding comprises computer-readable program code means for causing a computer to affect encoding each frame of said variable number of frames temporally subsequent to said I frame as a B frame, and wherein said GOP length comprises said encoded I frame and said variable number of encoded B frames only.

An article of manufacture, comprising:

• a computer usable medium having a computer-readable program code means embodied therein for causing a computer to affect encoding of a sequence of video frames, the computer-readable program code means in said article of manufacture comprising:
• computer-readable program code means for causing a computer to affect encoding the sequence of video frames to produce an encoded bitstream;
• computer-readable program code means for causing a computer to affect dynamically determining, as a function of frame variation between a frame and a reference frame within the sequence of video frames, a group of picture (GOP) length for at least one GOP of the encoded bitstream, said dynamically determining occurring during said encoding;
• and
• wherein said computer-readable program code means for causing a computer to affect dynamically determining comprises computer-readable program code means for causing a computer to affect dynamically determining said GOP length by directing said encoding to encode a frame of the sequence of video frames as an I frame, said I frame comprising said reference frame, and to encode subsequent frames of the sequence of video frames using motion estimation based on said I frame, and wherein said computer-readable program code means for causing a computer to affect dynamically determining further comprises computer-readable program code means for causing a computer to affect beginning a new GOP when an encoded frame of said subsequent frames has a predefined picture degradation compared with said I frame.