Method for low memory footprint compressed video decoding
This invention is a method of memory saving in compressed video decoding. For each group of pictures the method determines whether less than the maximum number N reference frames are needed for decoding. If so, then a memory is configuring for the needed number M reference frames less than N. If not, the memory is configured for N reference frames. The group of pictures is decoding the group of pictures using the configured number of reference frames.
1. A computer implemented method of compressed video decoding comprising the steps of:
for each group of pictures determining a number of reference frames M needed for decoding including considering stream properties of the group of pictures and frame types of pictures of the group of pictures from among the frame types including non-predicted frames (I), predicted frames (P) and bidirectionally predicted frames (B);
if M is less than N, where N is the maximum number of reference frames needed for decoding video any group of pictures of the current pixel resolution, configuring a memory for M reference frames;
if M is not less than N, configuring a memory for N reference frames; and
allocating an amount of memory to store the configured number of reference frames;
decoding the group of pictures using the configured number of reference frames.
2. The computer implemented method of claim 1 , wherein:
the maximum number of reference frames needed for decoding video of the current pixel resolution N for HD frames of 1920 pixels by 1080 pixels resolution is 5.
3. The computer implemented method of claim 1 , wherein:
the maximum number of reference frames needed for decoding video of the current pixel resolution N for D1 frames of 720 pixels by 480 pixels resolution is 6.
4. The computer implemented method of claim 1 , wherein:
the maximum number of reference frames needed for decoding video of the current pixel resolution N for CIF frames of 352 pixels by 288 pixels resolution is 16.
5. The computer implemented method of claim 1 , wherein:
said step of determining a number of reference frames M needed for decoding determines a single reference frame is needed to decode a group of frames having sequential frame types I, P, P, P, P.
6. The computer implemented method of claim 1 , wherein:
said step of determining a number of reference frames M needed for decoding determines two reference frames are needed to decode a group of frames having sequential frame types I, B, P, B, P, B, P.