A method for providing video stream data, comprising: accessing a multi-view image stream encoded with a plurality of primary image streams and a plurality of secondary image streams, wherein the plurality of primary image streams comprises a plurality of sequences of single-view images generated from image data captured with a plurality of cameras, wherein each sequence of single-view images in the plurality of sequences of single-view images comprises a plurality of groups of pictures, GOPs, wherein a GOP in the plurality of GOPs comprises I- and non-I-frames, wherein the plurality of secondary image streams comprises a plurality of sequences of reconstructed I-frames each of which is derived from a corresponding non-I-frame as well as preceding I- and non-I-frame(s) in the same GOP of the primary image stream; receiving, from a recipient decoding device, viewpoint data of a viewer collected in real time while the viewer is viewing video content derived from a subset of image data in the multi-view image stream, wherein the viewpoint data indicates the viewer's viewpoint has changed starting from a specific time point; selecting, based on the viewer's changed viewpoint, a camera from among a plurality of cameras, wherein a video content portion derived from an image data portion captured by the selected camera is to be rendered in the viewer's viewport after the specific time point; in response to determining that the specific time point corresponds to a non-I-frame in a GOP of a primary image stream generated from image data captured by the selected camera, transmitting, to the recipient decoding device, an I-frame from a secondary image stream corresponding to the non-I-frame at the specific time point in the GOP of the primary image stream generated from image data captured by the selected camera; in response to determining that the specific time point corresponds to an I-frame in the GOP of the primary image stream generated from image data captured by the selected camera, transmitting, to the recipient decoding device, the I-frame; and transmitting, to the recipient decoding device, one or more subsequent non-I-frames in the GOP of the primary image stream. accessing a multi-view image stream encoded with a plurality of primary image streams and a plurality of secondary image streams, wherein the plurality of primary image streams comprises a plurality of sequences of single-view images generated from image data captured with a plurality of cameras, wherein each sequence of single-view images in the plurality of sequences of single-view images comprises a plurality of groups of pictures, GOPs, wherein a GOP in the plurality of GOPs comprises I- and non-I-frames, wherein the plurality of secondary image streams comprises a plurality of sequences of reconstructed I-frames each of which is derived from a corresponding non-I-frame as well as preceding I- and non-I-frame(s) in the same GOP of the primary image stream; receiving, from a recipient decoding device, viewpoint data of a viewer collected in real time while the viewer is viewing video content derived from a subset of image data in the multi-view image stream, wherein the viewpoint data indicates the viewer's viewpoint has changed starting from a specific time point; selecting, based on the viewer's changed viewpoint, a camera from among a plurality of cameras, wherein a video content portion derived from an image data portion captured by the selected camera is to be rendered in the viewer's viewport after the specific time point; in response to determining that the specific time point corresponds to a non-I-frame in a GOP of a primary image stream generated from image data captured by the selected camera, transmitting, to the recipient decoding device, an I-frame from a secondary image stream corresponding to the non-I-frame at the specific time point in the GOP of the primary image stream generated from image data captured by the selected camera; in response to determining that the specific time point corresponds to an I-frame in the GOP of the primary image stream generated from image data captured by the selected camera, transmitting, to the recipient decoding device, the I-frame; and transmitting, to the recipient decoding device, one or more subsequent non-I-frames in the GOP of the primary image stream.