In some cases like virtualization one processor has exactly one core. But there is s strict number of MAX_PROCESSOR_GROUP which is 16. https://github.com/OpenVisualCloud/SVT-VP9/blob/master/Source/Lib/Codec/EbEncHandle.c#L137 The suggestion is to increase this value to 1024. Also it is better to replace this line https://github.com/OpenVisualCloud/SVT-VP9/blob/master/Source/Lib/Codec/EbEncHandle.c#L406 with ```text if (socket_id < 0 || socket_id > MAX_PROCESSOR_GROUP - 1) { ```