Transcoding ultra-high-definition panoramic videos

Abstract

In one example, a processing system including at least one processor may obtain viewport information of a mobile computing device associated with a panoramic video, map the viewport information to a plurality of blocks of a frame of the panoramic video in accordance with a cube map projection of the frame, encode the plurality of blocks into a projected frame, and transmit the projected frame to the mobile computing device. In another example, a processing system of a mobile computing device including at least one processor may obtain viewport information of the device associated with a panoramic video, transmit to a server the viewport information, obtain from the server a projected frame of the panoramic video comprising a plurality of blocks of a frame of the panoramic video that are associated with the viewport information in accordance with a cube map projection of the frame, and buffer the projected frame.

What is claimed is: 
     
         1 . A method comprising:
 obtaining, by a processing system including at least one processor, viewport information of a mobile computing device associated with a panoramic video;   mapping, by the processing system, the viewport information to a plurality of blocks of a frame of the panoramic video in accordance with a cube map projection of the frame;   encoding, by the processing system, the plurality of blocks into a projected frame; and   transmitting, by the processing system, the projected frame to the mobile computing device.   
     
     
         2 . The method of  claim 1 , wherein the cube map projection of the frame comprises six faces, wherein each of the six faces is divided into an equal set of blocks. 
     
     
         3 . The method of  claim 1 , wherein the viewport information comprises a predicted viewport of the mobile computing device. 
     
     
         4 . The method of  claim 3 , wherein the mapping comprises:
 identifying the plurality of blocks of the frame in accordance with the predicted viewport and a viewport-to-block identification mapping.   
     
     
         5 . The method of  claim 1 , wherein the viewport information comprises identifications of the plurality of blocks of the frame. 
     
     
         6 . The method of  claim 5 , wherein the mobile computing devices identifies the plurality of blocks of the frame in accordance with a predicted viewport of the mobile computing device and a viewport-to-block identification mapping. 
     
     
         7 . The method of  claim 1 , wherein the mapping comprises:
 determining a predicted viewport of the mobile computing device from the viewport information; and   identifying the plurality of blocks of the frame in accordance with the predicted viewport and a viewport-to-block identification mapping.   
     
     
         8 . The method of  claim 1 , wherein the projected frame includes identifications of the plurality of blocks. 
     
     
         9 . The method of  claim 8 , wherein the mobile computing device is to present at least a portion of the projected frame in accordance with the identifications of the plurality of blocks. 
     
     
         10 . The method of  claim 1 , wherein the viewport information comprises viewport trajectory information of the mobile computing device, wherein the plurality of blocks comprises blocks that overlap with a predicted viewport of the mobile computing device in accordance with the viewport information, and wherein the plurality of blocks further comprises blocks that are outside of the predicted viewport in a direction in accordance with the viewport trajectory. 
     
     
         11 . The method of  claim 1 , wherein the frame is of a 16K resolution and the projected frame is of an 8K resolution, or wherein the frame is of an 8K resolution and the projected frame is of a 4K resolution. 
     
     
         12 . The method of  claim 1 , wherein the projected frame is encoded according to at least one of:
 a H.264 encoding; or   a H.265 encoding.   
     
     
         13 . The method of  claim 1 , wherein the panoramic video comprises a 360-degree video. 
     
     
         14 . A non-transitory computer-readable medium storing instructions which, when executed by a processing system including at least one processor, cause the processing system to perform operations, the operations comprising:
 obtaining viewport information of a mobile computing device associated with a panoramic video;   mapping the viewport information to a plurality of blocks of a frame of the panoramic video in accordance with a cube map projection of the frame;   encoding the plurality of blocks into a projected frame; and   transmitting the projected frame to the mobile computing device.   
     
     
         15 . The non-transitory computer-readable medium of  claim 14 , wherein the cube map projection of the frame comprises six faces, wherein each of the six faces is divided into an equal set of blocks. 
     
     
         16 . The non-transitory computer-readable medium of  claim 14 , wherein the viewport information comprises a predicted viewport of the mobile computing device. 
     
     
         17 . A method comprising:
 obtaining, by a processing system of a mobile computing device including at least one processor, viewport information of the mobile computing device associated with a panoramic video;   transmitting, by the processing system to a server, the viewport information of the mobile computing device;   obtaining, by the processing system from the server, a projected frame of the panoramic video, the projected frame comprising a plurality of blocks of a frame of the panoramic video that are associated with the viewport information in accordance with a cube map projection of the frame; and   buffering, by the processing system, the projected frame at the mobile computing device.   
     
     
         18 . The method of  claim 17 , further comprising:
 presenting, by the processing system, at least a portion of the projected frame via the mobile computing device.   
     
     
         19 . The method of  claim 17 , wherein the projected frame includes identifications of the plurality of blocks. 
     
     
         20 . The method of  claim 19 , further comprising:
 presenting, by the processing system, at least a portion of the projected frame via the mobile computing device, in accordance with the identifications of the plurality of blocks.