Method and device for adapting encoding of image frames of a video

A non-transitory computer readable storage medium having stored thereon instructions for implementing a method, when executed in a device having processing capabilities, the method for adapting encoding of image frames of a video, wherein the image frames are arranged in a sequence of groups of pictures, GOPs, and wherein each GOP contains an intra frame and a plurality of successive inter frames, the method comprising:

• determining a start of a second GOP subsequent to a first GOP in the sequence of GOPs;
• and
• adapting encoding of each of, or a subset of, a predetermined number of inter frames of the first GOP which immediately precede the determined start of the second GOP, such that the total size of the predetermined number of inter frames of the first GOP with adapting encoding is smaller than the size of the predetermined number of inter frames of the first GOP would have been without adapting encoding,
• adapting encoding of an intra frame of the second GOP by increasing a compression of the intra frame of the second GOP such that the total size of the intra frame of the second GOP is smaller than the size of the intra frame of the second GOP would have been without adapting encoding,
• adapting encoding of one or more inter frames of the second GOP which immediately succeed the intra frame of the second GOP by increasing a compression of the one or more inter frames of the second GOP, such that the total size of the one or more inter frames of the second GOP is smaller than the size of the one or more inter frames of the second GOP would have been without adapting encoding,
• the method further comprising enabling cancellation of quantized transform coefficients when encoding inter frames of the first GOP, and wherein adapting encoding of one or more inter frames of the second GOP which immediately succeed the intra frame of the second GOP further comprises disabling cancellation of quantized transform coefficients.

A device for adapting encoding of image frames of a video, wherein the image frames are arranged in a sequence of groups of pictures, GOPs, and wherein each GOP contains an intra frame and a plurality of successive inter frames, the device comprising circuitry configured to execute functions for implementing a method comprising:

• determining a start of a second GOP subsequent to a first GOP in the sequence of GOPs;
• and
• adapting encoding of each of, or a subset of, a predetermined number of inter frames of the first GOP which immediately precede the determined start of the second GOP, such that the total size of the predetermined number of inter frames of the first GOP with adapting encoding is smaller than the size of the predetermined number of inter frames of the first GOP would have been without adapting encoding,
• adapting encoding of an intra frame of the second GOP by increasing a compression of the intra frame of the second GOP such that the total size of the intra frame of the second GOP is smaller than the size of the intra frame of the second GOP would have been without adapting encoding,
• adapting encoding of one or more inter frames of the second GOP which immediately succeed the intra frame of the second GOP by increasing a compression of the one or more inter frames of the second GOP, such that the total size of the one or more inter frames of the second GOP is smaller than the size of the one or more inter frames of the second GOP would have been without adapting encoding,
• the method further comprising enabling cancellation of quantized transform coefficients when encoding inter frames of the first GOP, and wherein adapting encoding of one or more inter frames of the second GOP which immediately succeed the intra frame of the second GOP further comprises disabling cancellation of quantized transform coefficients.