diff options
Diffstat (limited to 'src/xine-engine/spu_decoder.h')
| -rw-r--r-- | src/xine-engine/spu_decoder.h | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/src/xine-engine/spu_decoder.h b/src/xine-engine/spu_decoder.h index d4bd691f1..24afd745b 100644 --- a/src/xine-engine/spu_decoder.h +++ b/src/xine-engine/spu_decoder.h @@ -114,4 +114,31 @@ struct spu_decoder_s { void *node; /* used by plugin loader */ }; + +/* SPU decoders differ from video and audio decoders in one significant + * way: unlike audio and video, SPU streams are not continuous; + * this results in another difference, programmers have to consider: + * while both audio and video decoders are automatically blocked in + * their get_buffer()/get_frame() methods when the output cannot take + * any more data, this does not work for SPU, because it could take + * minutes before the next free slot becomes available and we must not + * block the decoder thread for that long; + * therefore, we provide a convenience function for SPU decoders which + * implements a wait until a timestamp sufficiently close to the VPTS + * of the next SPU is reached, but the waiting will end before that, + * if some outside condition requires us to release the decoder thread + * to other tasks; + * if this functions returns with 1, noone needs the decoder thread and + * you may continue waiting; if it returns 0, finish whatever you are + * doing and return; + * the usual pattern for SPU decoders is this: + * + * do { + * spu = prepare_spu(); + * int thread_vacant = _x_spu_decoder_sleep(this->stream, spu->vpts); + * int success = process_spu(spu); + * } while (!success && thread_vacant); + */ +int _x_spu_decoder_sleep(xine_stream_t *, int64_t next_spu_vpts); + #endif /* HAVE_SPUDEC_H */ |