Error Resilience in Video Decoding

A video decoder for decoding an encoded video stream, wherein decoding an encoded video stream comprises:

• when a sequence parameter set in the encoded video stream is lost, wherein the sequence parameter set comprises a frame number parameter, a picture order count parameter, a picture height parameter, a picture width parameter, and a plurality of non-critical parameters,
• assigning default values to the plurality of non-critical parameters;
• setting the picture height parameter and the picture width parameter based on a common pixel resolution;
• when a slice header of an instantaneous decoding refresh picture is available,
• determining the frame number parameter from the slice header, and
• determining the picture order count parameter using the frame number parameter, the default values, the pixel height parameter, and the picture width parameter;
• and
• using the picture order count parameter, the frame number parameter, the default values, the pixel height parameter, and the picture width parameter to decode a slice in the encoded video stream.

A digital system comprising:

• a processor;
• a memory;
• and
• a video decoder configured to decode an encoded video stream by:
• when a sequence parameter set in the encoded video stream is lost, wherein the sequence parameter set comprises a frame number parameter, a picture order count parameter, a picture height parameter, a picture width parameter, and a plurality of non-critical parameters,
• assigning default values to the plurality of non-critical parameters;
• setting the picture height parameter and the picture width parameter based on a common pixel resolution;
• when a slice header of an instantaneous decoding refresh picture is available,
• determining the frame number parameter from the slice header, and
• determining the picture order count parameter using the frame number parameter, the default values, the pixel height parameter, and the picture width parameter;
• when a slice header of an instantaneous decoding refresh picture is not available,
• determining the frame number parameter and the picture order count parameter using the default values, the pixel height parameter, and the picture width parameter;
• and
• using the picture order count parameter, the frame number parameter, the default values, the pixel height parameter, and the picture width parameter to decode a slice in the encoded video stream.