Techniques and systems are provided for processing video data. In one example, a media file associated with 360-degree video data can be obtained. The 360-degree video data may include a spherical representation of a scene. The media file may include first signaling information and second signaling information of a viewport region corresponding to a region of interest (ROI) in the spherical representation. The first signaling information may include a center position and a dimension of the viewport region measured in a spherical space associated with the spherical representation. The second signaling information may indicate a region of a picture comprising the viewport region, the picture being formed by projecting the spherical representation including the ROI onto a plane. Pixels corresponding to the viewport region from the data of the picture can be extracted based on the first signaling information and second signaling information, and can be provided for rendering.