ENCODING VIDEO WITH EXTENDED LONG TERM REFERENCE PICTURE RETENTION
An encoder for video encoding and decoding with long term reference picture retention. The encoder generates an encoded bitream for a compliant decoder. At the decoder, coded pictures are decoded using a list of references pictures, of which at least one is a long term reference picture. A first picture is decoded using the long term reference picture. A second picture is decoded without using the long term reference picture which is inactive but is retained in a buffer. A subsequent picture is then decoded again using the long term reference picture.
1 . A non-transitory computer readable media storing a bitstream encoded by a video encoder configured to encode a bitstream, the bit stream including signaling information and a plurality of coded pictures including first coded picture, second coded picture, and a subsequent coded picture, the decoder performing a decoding method for decoding the plurality of pictures including the first, second and subsequent pictures and store the decoded pictures in a decoded picture buffer, where the decoding method comprises:
decoding the first picture by forming a first list of active reference pictures from the pictures in the buffer, one of the active reference pictures being a long term reference picture which is an Instantaneous Decoding Refresh (IDR) picture, and decoding a block of said first picture using the long term reference IDR picture;
decoding the second picture by forming a second list of active reference pictures from the pictures in the buffer, said second list not including the long term reference IDR picture and, in response to at least one parameter in the signaling information, indicating that the long term reference IDR picture is inactive as a reference picture while continuing to store the long term reference IDR picture in the buffer; and
decoding the subsequent picture by forming a subsequent list of active reference pictures from the pictures in the buffer including, in response to at least one parameter in the signaling information, changing the indication of the long term reference picture from inactive to active as a reference picture and including the long term reference IDR picture in the third list, and decoding a block from the subsequent picture using the long term reference IDR picture.
2 . The non-transitory computer readable media of claim 1 further configured to provide signaling information to mark the long term reference IDR picture as unused for reference and remove the long term reference picture from the buffer.
3 . The non-transitory computer readable media of claim 1 , wherein signaling information includes a time related parameter indicating that the long term reference IDR picture is inactive.
4 . The non-transitory computer readable media encoder of claim 1 , wherein the bitstream is a single view bitstream.
5 . The non-transitory computer readable media of claim 1 , wherein the bitstream includes a signal to remove the at least a first picture from the buffer.
6 . A video decoder comprising circuitry which is configured to:
receive a bit stream including signaling information and a plurality of coded pictures including first coded picture, second coded picture, and a subsequent coded picture;
decode the first coded picture by forming a first list of active reference pictures from the pictures in the buffer, one of the active reference pictures being a long term reference picture , and decoding a first inter-predicted block of said first picture using the long term reference picture and decoding a second block of the first picture using intra-prediction,
decode the second coded picture by forming a second list of active reference pictures from the pictures in the buffer, said second list not including the long term reference picture and, in response to at least one parameter in the signaling information, indicating that the long term reference picture is inactive as a reference picture while continuing to store the long term reference picture in the buffer; the second picture including a first inter-predicted block which is decoded using one of the reference pictures in the second list and a second block which is decoded using intra-prediction,
decode the subsequent coded picture by forming a subsequent list of active reference pictures from the pictures in the buffer including, in response to at least one parameter in the signaling information, changing the indication of the long term reference picture from inactive to active as a reference picture and including the long term reference picture in the subsequent list, and decoding a first inter-predicted block from the subsequent picture using the long term reference picture and decoding a second block of the subsequent picture using intra-prediction.
7 . The video decoder of claim 6 further configured to provide signaling information to mark the long term reference picture as unused for reference and remove the long term reference picture from the buffer.
8 . The video decoder of claim 6 , wherein signaling information includes a time related parameter indicating that the long term reference picture is inactive.
9 . The video decoder of claim 6 , wherein the bitstream is a single view bitstream.
10 . The video decoder of claim 6 , wherein the bitstream includes a signal to remove the at least a first coded picture from the buffer.
11 . A video encoder generating a coded bitstream including signaling information and a plurality of coded pictures including first coded picture, second coded picture, and a subsequent coded picture, the coded bitstream being decodable by a decoder performing a decoding method comprising:
receiving a bit stream including signaling information and a plurality of coded pictures including first coded picture, second coded picture, and a subsequent coded picture;
decoding the first coded picture by forming a first list of active reference pictures from the pictures in the buffer, one of the active reference pictures being a long term reference picture, and decoding a first inter-predicted block of said first picture using the long term reference picture and decoding a second block of the first picture using intra-prediction,
decoding the second coded picture by forming a second list of active reference pictures from the pictures in the buffer, said second list not including the long term reference picture and, in response to at least one parameter in the signaling information, indicating that the long term reference picture is inactive as a reference picture while continuing to store the long term reference picture in the buffer; the second picture including a first inter-predicted block which is decoded using one of the reference pictures in the second list and a second block which is decoded using intra-prediction,
decoding the subsequent coded picture by forming a subsequent list of active reference pictures from the pictures in the buffer including, in response to at least one parameter in the signaling information, changing the indication of the long term reference picture from inactive to active as a reference picture and including the long term reference picture in the subsequent list, and decoding a first inter-predicted block from the subsequent picture using the long term reference picture and decoding a second block of the subsequent picture using intra-prediction.
12 . The video encoder of claim 11 further configured to provide signaling information to mark the long term reference picture as unused for reference and remove the long term reference picture from the buffer.
13 . The video encoder of claim 11 , wherein signaling information includes a time related parameter indicating that the long term reference picture is inactive.
14 . The video encoder of claim 11 , wherein the bitstream is a single view bitstream.
15 . The video encoder of claim 11 , wherein the bitstream includes a signal to remove the at least a first picture from the buffer.
16 . A non-transitory computer readable media storing a bitstream encoded by a video encoder configured to encode a bitstream including signaling information and a plurality of coded pictures including first coded picture, second coded picture, and a subsequent coded picture, the decoder performing a decoding method comprising:
receiving the bit stream including signaling information and a plurality of coded pictures including first coded picture, second coded picture, and a subsequent coded picture;
decoding the first coded picture by forming a first list of active reference pictures from the pictures in the buffer, one of the active reference pictures being a long term reference picture, and decoding a first inter-predicted block of said first picture using the long term reference picture and decoding a second block of the first picture using intra-prediction,
decoding the second coded picture by forming a second list of active reference pictures from the pictures in the buffer, said second list not including the long term reference picture and, in response to at least one parameter in the signaling information, indicating that the long term reference picture is inactive as a reference picture while continuing to store the long term reference picture in the buffer; the second picture including a first inter-predicted block which is decoded using one of the reference pictures in the second list and a second block which is decoded using intra-prediction,
decoding the subsequent coded picture by forming a subsequent list of active reference pictures from the pictures in the buffer including, in response to at least one parameter in the signaling information, changing the indication of the long term reference picture from inactive to active as a reference picture and including the long term reference picture in the subsequent list, and decoding a first inter-predicted block from the subsequent picture using the long term reference picture and decoding a second block of the subsequent picture using intra-prediction.
17 . The non-transitory computer readable media of claim 16 further configured to provide signaling information to mark the long term reference picture as unused for reference and remove the long term reference picture from the buffer.
18 . The non-transitory computer readable media of claim 16 , wherein signaling information includes a time related parameter indicating that the long term reference picture is inactive.
19 . The non-transitory computer readable media encoder of claim 16 , wherein the bitstream is a single view bitstream.
20 . The non-transitory computer readable media of claim 16 , wherein the bitstream includes a signal to remove the at least a first picture from the buffer.