A method for transmitting point cloud data, the method comprising: encoding point cloud data, wherein the encoding the point cloud data includes: encoding geometry data of point cloud data; encoding attribute data of the point cloud data; encoding occupancy data of the point cloud data; encapsulating the encoded geometry data, the encoded attribute data and the encoded occupancy data into component tracks of a file based on a ISO base media file format, ISOBMFF; and transmitting the file, wherein the file further includes a timed metadata track including a sample entry and samples, wherein the sample entry includes bounding box information including: information for a number of bounding boxes carried in the timed metadata track, a first flag indicating whether an offset of each of the bounding boxes remains unchanged in all the samples referring to the sample entry or the offset is indicated in the sample, a second flag indicating whether scale factors of all axes of each of the bounding boxes remains unchanged in all the samples referring to the sample entry or the scale factors are indicated in the sample, a third flag indicating whether a width, a height or a depth of each of the bounding boxes remains unchanged in all the samples referring to the sample entry or the width, height or depth is indicated in the sample, a fourth flag indicating whether one or more rectangular regions where point cloud within each of the bounding boxes is projected in coded pictures remain unchanged in all the samples referring to the sample entry or the one or more rectangular regions where point cloud within each of the bounding boxes is projected in coded pictures are indicated in the sample, wherein an object in the spatial regions moves over time and the bounding box information is dynamically changing over time. encoding geometry data of point cloud data; encoding attribute data of the point cloud data; encoding occupancy data of the point cloud data; encapsulating the encoded geometry data, the encoded attribute data and the encoded occupancy data into component tracks of a file based on a ISO base media file format, ISOBMFF; and transmitting the file, wherein the file further includes a timed metadata track including a sample entry and samples, wherein the sample entry includes bounding box information including: information for a number of bounding boxes carried in the timed metadata track, a first flag indicating whether an offset of each of the bounding boxes remains unchanged in all the samples referring to the sample entry or the offset is indicated in the sample, a second flag indicating whether scale factors of all axes of each of the bounding boxes remains unchanged in all the samples referring to the sample entry or the scale factors are indicated in the sample, a third flag indicating whether a width, a height or a depth of each of the bounding boxes remains unchanged in all the samples referring to the sample entry or the width, height or depth is indicated in the sample, a fourth flag indicating whether one or more rectangular regions where point cloud within each of the bounding boxes is projected in coded pictures remain unchanged in all the samples referring to the sample entry or the one or more rectangular regions where point cloud within each of the bounding boxes is projected in coded pictures are indicated in the sample, information for a number of bounding boxes carried in the timed metadata track, a first flag indicating whether an offset of each of the bounding boxes remains unchanged in all the samples referring to the sample entry or the offset is indicated in the sample, a second flag indicating whether scale factors of all axes of each of the bounding boxes remains unchanged in all the samples referring to the sample entry or the scale factors are indicated in the sample, a third flag indicating whether a width, a height or a depth of each of the bounding boxes remains unchanged in all the samples referring to the sample entry or the width, height or depth is indicated in the sample, a fourth flag indicating whether one or more rectangular regions where point cloud within each of the bounding boxes is projected in coded pictures remain unchanged in all the samples referring to the sample entry or the one or more rectangular regions where point cloud within each of the bounding boxes is projected in coded pictures are indicated in the sample, wherein an object in the spatial regions moves over time and the bounding box information is dynamically changing over time.