Data storage device and method for progressive fading for video surveillance systems
A data storage device and method for progressive fading for video surveillance systems are provided. In one embodiment, a data storage device is provided comprising a memory and a controller. The controller is configured to store a plurality of digital video frames in the memory over time; and create free space in the memory by deleting some of the plurality of digital video frames across a plurality of subsets of digital video frames, wherein fewer digital video frames are deleted from a subset stored more recently in time than from a subset stored less recently in time. Other embodiments are provided.
1. A data storage device comprising:
a memory; and
a controller configured to:
store 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:
calculate a number of digital video frames to be deleted from the memory based on an amount of incoming data from the host;
respectively identify a plurality of progressively-higher frequencies of digital video frame deletion for a plurality of subsets 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
delete 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
store the additional digital video frames in free space in the memory created by the deleting of the calculated number of digital video frames.
2. The data storage device of claim 1 , wherein the controller is further configured to update a frame map identifying which frames of the plurality of digital video frames to play after the calculated number of digital video frames has been deleted.
3. The data storage device of claim 2 , wherein the controller is further configured to:
use the frame map to identify which digital video frames to play.
4. The data storage device of claim 3 , wherein the controller is further configured to play the identified digital video frames.
5. The data storage device of claim 1 , wherein the plurality of digital video frames comprises a surveillance video.
6. The data storage device of claim 1 , wherein the memory comprises a three-dimensional memory.
7. The data storage device of claim 1 , wherein the controller is further configured to dynamically determine a number of subsets in the plurality of subsets of the plurality of digital video frames based on the calculated number of digital video frames to be deleted.
8. The data storage device of claim 1 , wherein the host comprises a computer.
9. The data storage device of claim 1 , wherein the host comprises a mobile phone.
10. The data storage device of claim 1 , wherein the host comprises a tablet.
11. The data storage device of claim 1 , wherein the host comprises a wearable device.
12. The data storage device of claim 1 , wherein the host comprises a digital video recorder.
13. The data storage device of claim 1 , wherein the host comprises a surveillance system.
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.
15. The method of claim 14 , wherein the plurality of digital video frames comprises a surveillance video.
16. The method of claim 14 , further comprising updating a frame map identifying which frames of the plurality of digital video frames to play after the calculated number of digital video frames has been deleted.
17. The method of claim 16 , further comprising:
using the frame map to identify which digital video frames to play.
18. The method of claim 17 , further comprising playing the identified digital video frames.
19. The method of claim 14 , further comprising determining a number of subsets in the plurality of subsets of the plurality of digital video frames based on the calculated number of digital video frames to be deleted.
20. A data storage device comprising:
a memory;
means for 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;
means for performing the following 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 of the plurality of subsets of the plurality of digital video frames at its identified frequency of digital video frame deletion; and
means for storing the additional digital video frames in free space in the memory created by the deleting of the calculated number of digital video frames.