Multi-resolution pyramid for georeferenced video
Examples of systems and methods for delivering overhead video to a computing device are provided. Delivering the overhead video can include generating multiple versions of the overhead video having respective resolutions, bitrates, or frame rates. The system can then generate georeferenced video data for each version by incorporating georeferencing coordinates and time synchronization information. The georeferenced video data can be stored in transcoded video files. In response to a request from a computing device for video data of a geographical region, the system can transmit a primary video stream comprising georeferenced video data of a relatively high quality and a secondary video stream comprising georeferenced video data of a relatively low quality, wherein the primary video stream includes the geographical region and the secondary video stream includes a proximal geographical region.
1. A method for delivering overhead video to a computing device, the method comprising:
under control of an overhead video delivery system comprising computing hardware:
receiving overhead video from an overhead imaging platform;
generating a first version of the overhead video having a first resolution;
generating a second version of the overhead video having a second resolution, the second resolution being less than the first resolution;
creating first georeferenced video data and second georeferenced video data by incorporating georeferencing coordinates and time synchronization information into the first version of the overhead video data and the second version of the overhead video data, respectively;
storing the first georeferenced video data and the second georeferenced video data in one or more transcoded video files; and
transmitting to the computing device a primary video stream comprising the first georeferenced video data and a secondary video stream comprising the second georeferenced video data,
wherein the primary video stream includes images of a geographical region and the secondary video stream includes images of a proximal geographical region.
2. The method of claim 1 , wherein transmitting to the computing device is accomplished using less than or equal to about 512 kilobits per second (kbps) of bandwidth over a network connection.
3. The method of claim 1 , wherein the primary video stream comprises a transcoded video file with a data rate that is less than or equal to 100 kilobits per second (kbps).
4. The method of claim 3 , wherein the secondary video stream comprises a transcoded video file with a data rate that is less than or equal to 50 kilobits per second (kbps).
5. The method of claim 1 , wherein the secondary video stream comprises at least 8 transcoded video files comprising imagery adjacent to the imagery of the geographical region in the primary video stream.
6. The method of claim 1 , wherein the first resolution is at least about 1920 pixels by 1080 pixels.
7. The method of claim 6 , wherein the second resolution is at least about 640 pixels by 360 pixels.
8. The method of claim 1 , wherein a ratio of the second resolution to the first resolution is less than or equal to ½.
9. The method of claim 8 , wherein the ratio is less than ⅓.
10. The method of claim 1 , wherein the overhead video comprises orthorectified overhead video.
11. The method of claim 1 , wherein the overhead imaging platform comprises an imaging satellite.
12. A system for delivering overhead video to a computing device, the system comprising:
non-transitory data storage configured to store overhead video;
computing hardware in communication with the non-transitory data storage, the computing device configured with instructions to execute:
a transcoding module configured to generate a transcoded video from the overhead video, the transcoded video having a multi-scale, pyramidal data format and including georeferencing coordinates and time synchronization information;
a rendered video storage module configured to store the transcoded video in one or more transcoded video files on the non-transitory data storage; and
a caching module configured to respond to requests for overhead video data from the computing device by:
retrieving a primary video stream comprising transcoded video files for a geographical region;
caching a secondary video stream comprising transcoded video files from geographical regions proximal to the geographical region; and
transmitting to the computing device the primary video stream and at least one of the cached transcoded video files of the secondary video stream.
13. The system of claim 12 , wherein a resolution of the cached transcoded video files of the secondary video stream is less than a resolution of the transcoded video files of the primary video stream.
14. The system of claim 12 , wherein a frame rate of the cached transcoded video files of the secondary video stream is less than a frame rate of the transcoded video files of the primary video stream.
15. The system of claim 12 , wherein an image compression ratio of the cached transcoded video files of the secondary video stream is greater than an image compression ratio of the transcoded video files of the primary video stream.
16. The system of claim 12 , wherein the cached transcoded video files of the secondary video stream comprises overhead video of regions adjacent to the geographical region.
17. The system of claim 12 , wherein the transcoding module is further configured to generate a resolution pyramid for the overhead video data.
18. The system of claim 12 , wherein the caching module is further configured to drop one or more frames from the cached transcoded video files while maintaining synchronization of the primary video stream and the secondary video stream through the time synchronization information.
19. Non-transitory computer storage configured with executable instructions for delivering overhead video data, the executable instructions comprising:
a transcoding module configured to transcode overhead video into multiple video streams and to encode the multiple video streams with georeferencing coordinates and time synchronization information;
a caching module configured to retrieve a primary video stream comprising a video stream that includes overhead video of a geographical region and to retrieve a plurality of secondary video streams comprising video streams that include imagery of geographical regions adjacent to the geographical region; and
a transmission module configured to send the primary video stream and the plurality of secondary video streams over a network to a receiving computing device,
wherein the primary video stream has a frame rate that is greater than a frame rate of each of the plurality of secondary video streams.
20. The non-transitory computer storage of claim 19 , wherein a bitrate of the primary video stream is greater than a bitrate of each of the plurality of secondary video streams.
21. The non-transitory computer storage of claim 19 , wherein a resolution of the primary video stream is greater than a resolution of each of the plurality of secondary video streams.
22. The non-transitory computer storage of claim 19 , wherein the caching module is further configured to:
retrieve at least one different secondary video stream during transmission of the primary video stream and the plurality of secondary video streams; and
send to the receiving computing device over the network the at least one different secondary video stream,
wherein the transmission module is configured to utilize the time synchronization information to send the at least one different secondary video stream synchronized in time with the primary video stream.
23. The non-transitory computer storage of claim 19 , wherein the caching module is further configured to select the primary video stream and the plurality of secondary video streams such that a data rate transmitted over the network is less than a bandwidth of the receiving computing device.