obfp += 2;
};
*obfp = 0;
-
-
+
+
// get raw timestamp information
// I think that a good way to understand these timestamps is that
// (1) the rtlt below is the timestamp of the frame that should be playing at the
// Thus, (3) the latency can be calculated by subtracting the second from the
// first.
// There must be more to it -- there something missing.
-
+
// In addition, it seems that if the value of the short represented by the second
// pair of bytes in the packet is 7
// then an extra time lag is expected to be added, presumably by
// the AirPort Express.
-
+
// Best guess is that this delay is 11,025 frames.
-
+
uint32_t rtlt = nctohl(&packet[4]); // raw timestamp less latency
uint32_t rt = nctohl(&packet[16]); // raw timestamp
-
+
uint32_t fl = nctohs(&packet[2]); //
-
+
debug(1,"Sync Packet of %d bytes received: \"%s\", flags: %d, timestamps %u and %u,
giving a latency of %d frames.",plen,obf,fl,rt,rtlt,rt-rtlt);
//debug(1,"Monotonic timestamps are: %" PRId64 " and %" PRId64 "
// valid for some minimum time (and thus may not be reliable), we need to invalidate
// last_anchor_info
+ if ((conn->airplay_stream_type == buffered_stream) &&
+ ((clock_id != conn->anchor_clock) || (conn->anchor_rtptime != rtptime) ||
+ (conn->anchor_time != networktime))) {
+ uint64_t master_clock_id = 0;
+ ptp_get_clock_info(&master_clock_id, NULL, NULL);
+ debug(1,
+ "Connection %d: Note: anchor parameters have changed. Old clock: %" PRIx64
+ ", rtptime: %u, networktime: %" PRIu64 ". New clock: %" PRIx64
+ ", rtptime: %u, networktime: %" PRIu64 ". Current master clock: %" PRIx64 ".",
+ conn->connection_number, conn->anchor_clock, conn->anchor_rtptime, conn->anchor_time,
+ clock_id, rtptime, networktime, master_clock_id);
+ }
+
if ((clock_id == conn->anchor_clock) &&
((conn->anchor_rtptime != rtptime) || (conn->anchor_time != networktime))) {
uint64_t time_now = get_absolute_time_in_ns();
int64_t last_anchor_validity_duration = time_now - conn->last_anchor_validity_start_time;
if (last_anchor_validity_duration < 5000000000) {
- debug(1,
- "Connection %d: Note: anchor parameters have changed before clock %" PRIx64
- " has stabilised.",
- conn->connection_number, clock_id);
+ if (conn->airplay_stream_type == buffered_stream)
+ debug(1,
+ "Connection %d: Note: anchor parameters have changed before clock %" PRIx64
+ " has stabilised.",
+ conn->connection_number, clock_id);
conn->last_anchor_info_is_valid = 0;
}
}
+
conn->anchor_remote_info_is_valid = 1;
+
+ // these can be modified if the master clock changes over time
conn->anchor_rtptime = rtptime;
conn->anchor_time = networktime;
conn->anchor_clock = clock_id;
+
+ // these are used to identify when the master clock becomes equal to the
+ // actual anchor clock information, so it can be used to avoid accumulating errors
+ conn->actual_anchor_rtptime = rtptime;
+ conn->actual_anchor_time = networktime;
+ conn->actual_anchor_clock = clock_id;
}
void reset_ptp_anchor_info(rtsp_conn_info *conn) {
// here we adjust the time of the anchor rtptime
// we know its local time, so we use the new clocks's offset to
// calculate what time that must be on the new clock
- conn->anchor_time = conn->last_anchor_local_time + actual_offset;
- conn->anchor_clock = actual_clock_id;
+
+ // but if the master clock has become equal to the actual anchor clock
+ // then we can reinstate it all
+ if (actual_clock_id == conn->actual_anchor_clock) {
+ debug(1, "Master clock has become equal to the anchor clock");
+ conn->anchor_clock = conn->actual_anchor_clock;
+ conn->anchor_time = conn->actual_anchor_time;
+ conn->anchor_rtptime = conn->actual_anchor_rtptime;
+ } else {
+ conn->anchor_time = conn->last_anchor_local_time + actual_offset;
+ conn->anchor_clock = actual_clock_id;
+ }
}
} else {
response = clock_not_valid; // no current clock information and no previous clock info
enum AVSampleFormat av_format;
switch (config.output_format) {
- case SPS_FORMAT_S32:
- case SPS_FORMAT_S32_LE:
- case SPS_FORMAT_S32_BE:
- case SPS_FORMAT_S24:
- case SPS_FORMAT_S24_LE:
- case SPS_FORMAT_S24_BE:
- case SPS_FORMAT_S24_3LE:
- case SPS_FORMAT_S24_3BE:
- av_format = AV_SAMPLE_FMT_S32;
- conn->input_bytes_per_frame = 8; // the output from the decoder will be input to the player
- conn->input_bit_depth = 32;
- debug(1,"32-bit output format chosen");
- break;
- case SPS_FORMAT_S16:
- case SPS_FORMAT_S16_LE:
- case SPS_FORMAT_S16_BE:
- av_format = AV_SAMPLE_FMT_S16;
- conn->input_bytes_per_frame = 4;
- conn->input_bit_depth = 16;
- break;
- case SPS_FORMAT_U8:
- av_format = AV_SAMPLE_FMT_U8;
- conn->input_bytes_per_frame = 2;
- conn->input_bit_depth = 8;
- break;
- default:
- debug(1,"Unsupported DAC output format %u. AV_SAMPLE_FMT_S16 decoding chosen. Good luck!", config.output_format);
- av_format = AV_SAMPLE_FMT_S16;
- conn->input_bytes_per_frame = 4; // the output from the decoder will be input to the player
- conn->input_bit_depth = 16;
- break;
+ case SPS_FORMAT_S32:
+ case SPS_FORMAT_S32_LE:
+ case SPS_FORMAT_S32_BE:
+ case SPS_FORMAT_S24:
+ case SPS_FORMAT_S24_LE:
+ case SPS_FORMAT_S24_BE:
+ case SPS_FORMAT_S24_3LE:
+ case SPS_FORMAT_S24_3BE:
+ av_format = AV_SAMPLE_FMT_S32;
+ conn->input_bytes_per_frame = 8; // the output from the decoder will be input to the player
+ conn->input_bit_depth = 32;
+ debug(1, "32-bit output format chosen");
+ break;
+ case SPS_FORMAT_S16:
+ case SPS_FORMAT_S16_LE:
+ case SPS_FORMAT_S16_BE:
+ av_format = AV_SAMPLE_FMT_S16;
+ conn->input_bytes_per_frame = 4;
+ conn->input_bit_depth = 16;
+ break;
+ case SPS_FORMAT_U8:
+ av_format = AV_SAMPLE_FMT_U8;
+ conn->input_bytes_per_frame = 2;
+ conn->input_bit_depth = 8;
+ break;
+ default:
+ debug(1, "Unsupported DAC output format %u. AV_SAMPLE_FMT_S16 decoding chosen. Good luck!",
+ config.output_format);
+ av_format = AV_SAMPLE_FMT_S16;
+ conn->input_bytes_per_frame = 4; // the output from the decoder will be input to the player
+ conn->input_bit_depth = 16;
+ break;
};
av_opt_set_sample_fmt(swr, "out_sample_fmt", av_format, 0);
ssize_t nread;
int finished = 0;
- int pcm_buffer_size =
- (1024 + 352) * conn->input_bytes_per_frame;
+ int pcm_buffer_size = (1024 + 352) * conn->input_bytes_per_frame;
uint8_t pcm_buffer[pcm_buffer_size];
int pcm_buffer_occupancy = 0;
new_buffer_needed = 1;
if (pcm_buffer_read_point != 0) {
// debug(1,"pcm_buffer_read_point (frames): %u, pcm_buffer_occupancy (frames): %u",
- // pcm_buffer_read_point/conn->input_bytes_per_frame, pcm_buffer_occupancy/conn->input_bytes_per_frame);
- // if there is anything to move down to the front of the buffer, do it now;
+ // pcm_buffer_read_point/conn->input_bytes_per_frame,
+ // pcm_buffer_occupancy/conn->input_bytes_per_frame); if there is anything to move down
+ // to the front of the buffer, do it now;
if ((pcm_buffer_occupancy - pcm_buffer_read_point) > 0) {
// move the remaining frames down to the start of the buffer
// debug(1,"move the remaining frames down to the start of the pcm_buffer");
debug(2,
"samples remaining before flush: %d, number of samples %d. "
"flushFromTS: %u, pcm_buffer_read_point_rtptime: %u.",
- samples_remaining, dst_bufsize / conn->input_bytes_per_frame, flush_from_timestamp,
- pcm_buffer_read_point_rtptime);
+ samples_remaining, dst_bufsize / conn->input_bytes_per_frame,
+ flush_from_timestamp, pcm_buffer_read_point_rtptime);
dst_bufsize = samples_remaining * conn->input_bytes_per_frame;
}
}
debug(1,
"pcm_buffer_read_point (frames): %u, pcm_buffer_occupancy "
"(frames): %u",
- pcm_buffer_read_point / conn->input_bytes_per_frame, pcm_buffer_occupancy / conn->input_bytes_per_frame);
+ pcm_buffer_read_point / conn->input_bytes_per_frame,
+ pcm_buffer_occupancy / conn->input_bytes_per_frame);
pcm_buffer_size = dst_bufsize + pcm_buffer_occupancy;
debug(1, "fatal error! pcm buffer too small at %d bytes.",
pcm_buffer_size);
projects / thirdparty / shairport-sync.git / commitdiff
