US 11,941,282 B2
Data storage device and method for progressive fading for video surveillance systems
Rohit Prasad, Karnataka (IN); and Ronak Jain, Karnataka (IN)
Assigned to Western Digital Technologies, Inc., San Jose, CA (US)
Filed by Western Digital Technologies, Inc., San Jose, CA (US)
Filed on Jun. 21, 2021, as Appl. No. 17/352,874.
Prior Publication US 2022/0404998 A1, Dec. 22, 2022
Int. Cl. G06F 3/06 (2006.01); H04N 7/18 (2006.01)
CPC G06F 3/0652 (2013.01) [G06F 3/0604 (2013.01); G06F 3/0679 (2013.01); H04N 7/18 (2013.01)] 20 Claims
OG exemplary drawing
 
14. A method comprising:
performing the following in a data storage device comprising a memory:
storing a plurality of digital video frames in the memory over time, wherein all of the digital video frames of the plurality of digital video frames are initially stored for playback at a same frame rate;
each time a free-up request is received from a host to create free space to store additional digital video frames:
calculating a number of digital video frames to be deleted from the memory based on an amount of incoming data from the host;
respectively identifying a plurality of progressively-higher frequencies of digital video frame deletion for a plurality of subsets of the plurality of digital video frames, wherein the plurality of subsets of the plurality of digital video frames are stored in time order and the frequency of digital video frame deletion of a given subset of the plurality of subsets of the plurality of digital video frames is higher than the frequency of digital video frame deletion of a subset of the plurality of subsets of the plurality of digital video frames that is stored earlier in the time order; and
deleting the calculated number of digital video frames by deleting digital video frames from each subset of the plurality of subsets of the plurality of digital video frames at its identified frequency of digital video frame deletion; and
storing the additional digital video frames in free space in the memory created by the deleting of the calculated number of digital video frames.