Method and device for generating a description file, and corresponding streaming method

Abstract

The present invention relates to a method and device for generating a description file about a video sequence at a server device for a client device, to retrieve a video segment and containing a region of interest. The method comprising for each video segment, determining a time interval during which the detected region of interest is spatially included in a same frame region in the video sequence; and generating a description file comprising spatial information describing the frame region and temporal information describing a duration at least equal to the determined time interval.

1 . A communication apparatus for transmitting a video having a plurality of image frames to another communication apparatus, the communication apparatus comprising:
 a reception unit configured to receive from the another communication apparatus a request for description data;   a first transmission unit configured to transmit, to the another communication apparatus which transmits the request for description data received by the reception unit, description data including first positional information indicating a spatial position of a partial region in a first image frame among the plurality of image frames; and   a second transmission unit configured to transmit image data which is encapsulated in order to allow an independent transmission of an image of the partial region to the another communication apparatus based on a request from the another communication apparatus which receives the description data transmitted by the first transmission unit,   wherein the first positional information is represented by top left corner position followed by width and height.   
     
     
         2 . The communication apparatus according to  claim 1 , wherein the description data includes second positional information indicating a spatial position of a partial region in a second image frame among the plurality of image frames. 
     
     
         3 . The communication apparatus according to  claim 1 , further comprising:
 a detection unit configured to detect an object from an image frame of the video, and   a generation unit configured to generate the description data based on a detection result obtained by the detection unit.   
     
     
         4 . The communication apparatus according to  claim 1 , further comprising:
 a detection unit configured to detect an object from an image frame of the video;   a specifying unit configured to specify a time period during which the detected object is spatially included in a same frame region of the video; and   a generation unit configured to generate the description data based on the time period specified by the specifying unit.   
     
     
         5 . The communication apparatus according to  claim 1 , wherein the description data is Media Presentation Description defined by MPEG-DASH. 
     
     
         6 . The communication apparatus according to  claim 3 , wherein the first positional information included in the description data is coordinate data representing the spatial position of the partial region. 
     
     
         7 . A communication method to transmit a video having a plurality of image frames from a first communication apparatus to another communication apparatus, wherein the first communication apparatus:
 receive, by a reception unit, from the another communication apparatus a request for description data;   transmit, by a first transmission unit, to the another communication apparatus which transmits the request for description data received by the reception unit, description data including first positional information indicating a spatial position of a partial region in a first image frame among the plurality of images frames; and   transmit, by a second transmission unit, image data which is encapsulated in order to allow an independent transmission of an image of the partial region to the another communication apparatus based on a request from the another communication apparatus which receives the description data transmitted by the transmission unit,   wherein the first positional information is represented by top left corner position followed by width and height.   
     
     
         8 . The communication method according to  claim 7 , wherein the description data includes second positional information indicating a spatial position of a partial region in a second image frame among the plurality of image frames. 
     
     
         9 . The communication method according to  claim 7 , further comprising:
 detect, by a detection unit, an object from an image frame of the video; and   generate, by a generation unit, the description data based on a detection result obtained by the detection unit.   
     
     
         10 . The communication method according to  claim 8 , further comprising:
 detect, by a detection unit, an object from an image frame of the video;   specify, by a specifying unit, a time period during which the detected object is spatially included in a same frame region of the video; and   generate, by a generation unit, the description data based on the time period specified by the specifying unit.   
     
     
         11 . The communication method according to  claim 7 , wherein the description data is Media Presentation Description defined by MPEG-DASH. 
     
     
         12 . The communication method according to  claim 9 , wherein the first positional information included in the description data is coordinate data representing the spatial position of the partial region. 
     
     
         13 . A communication apparatus that receives a video having a plurality of image frames from another communication apparatus, the communication apparatus comprising:
 a transmission unit configured to transmit to the another communication apparatus a request for description data;   a reception unit configured to receive, from the another communication apparatus which receives the request for description data transmitted by the transmission unit, description data including first positional information indicating a spatial position of a partial region in a first image frame among the plurality of image frames; and   wherein the transmission unit is further configured to transmit a request for the independent transmission of an image of the partial region determined in the first image frame, and   wherein the first positional information is represented by top left corner position followed by width and height.   
     
     
         14 . The communication apparatus according to  claim 13 , wherein the description data includes second positional information indicating a spatial position of a partial region in a second image frame among the plurality of image frames. 
     
     
         15 . The communication apparatus according to  claim 1 , wherein the description data is Media Presentation Description defined by MPEG-DASH. 
     
     
         16 . A communication method to receive, by a communication apparatus, a video having a plurality of image frames from another communication apparatus, wherein the communication apparatus:
 transmit, by a transmission unit, to the another communication apparatus a request for description data;   receive, by a reception unit, from the another communication apparatus which receives the request for description data transmitted by the transmission unit, description data including first positional information indicating a spatial position of a partial region in a first image frame among the plurality of image frames; and   transmit, by the transmission unit, a request for the independent transmission of an image of the partial region determined in the first image frame,   wherein the first positional information is represented by top left corner position followed by width and height.   
     
     
         17 . The communication apparatus according to  claim 16 , wherein the description data includes second positional information indicating a spatial position of a partial region in a second image frame among the plurality of image frames. 
     
     
         18 . The communication apparatus according to  claim 1 , wherein the description data is Media Presentation Description defined by MPEG-DASH. 
     
     
         19 . A computer-readable storage medium storing instructions of a computer program for implementing a method according to  claim 7 . 
     
     
         20 . A computer-readable storage medium storing instructions of a computer program for implementing a method according to  claim 16 .