  This paper introduces the fourth oriental language recognition (OLR)
challenge AP19-OLR, including the data profile, the tasks and the evaluation
principles. The OLR challenge has been held successfully for three consecutive
years, along with APSIPA Annual Summit and Conference (APSIPA ASC). The
challenge this year still focuses on practical and challenging tasks, precisely
(1) short-utterance LID, (2) cross-channel LID and (3) zero-resource LID. The
event this year includes more languages and more real-life data provided by
SpeechOcean and the NSFC M2ASR project. All the data is free for participants.
Recipes for x-vector system and back-end evaluation are also conducted as
baselines for the three tasks. The participants can refer to these
online-published recipes to deploy LID systems for convenience. We report the
baseline results on the three tasks and demonstrate that the three tasks are
worth some efforts to achieve better performance.
