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Seems to work for higher rates

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This commit is contained in:
Mike Brady
2018-10-19 22:14:23 +01:00
parent 6de64d5954
commit d2dba7cdba
4 changed files with 41 additions and 43 deletions
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rtp.c
+17 -21
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@@ -1034,13 +1034,14 @@ int have_timestamp_timing_information(rtsp_conn_info *conn) {
// right...
const int use_nominal_rate = 0; // specify whether to use the nominal input rate, usually 44100 fps
int sanitised_source_rate_information(int64_t *frames, uint64_t *time, rtsp_conn_info *conn) {
int sanitised_source_rate_information(uint32_t *frames, uint64_t *time, rtsp_conn_info *conn) {
int result = 1;
*frames = conn->input_rate;
*time = (uint64_t)(0x100000000); // one second in fp form
if ((conn->packet_stream_established) && (conn->initial_reference_time) &&
(conn->initial_reference_timestamp)) {
int64_t local_frames = conn->reference_timestamp - conn->initial_reference_timestamp;
// uint32_t local_frames = conn->reference_timestamp - conn->initial_reference_timestamp;
uint32_t local_frames = rtp_frame_offset(conn->initial_reference_timestamp, conn->reference_timestamp);
uint64_t local_time = conn->remote_reference_timestamp_time - conn->initial_reference_time;
if ((local_frames == 0) || (local_time == 0) || (use_nominal_rate)) {
result = 1;
@@ -1060,39 +1061,34 @@ int sanitised_source_rate_information(int64_t *frames, uint64_t *time, rtsp_conn
return result;
}
// we assume here that the timestamp is a timestamp calculated at the output rate, which could be an
// integer multiple of the input rate
// the timestamp is a timestamp calculated at the input rate
// the reference timestamps are denominated in terms of the input rate
int frame_to_local_time(int64_t timestamp, uint64_t *time, rtsp_conn_info *conn) {
int frame_to_local_time(uint32_t timestamp, uint64_t *time, rtsp_conn_info *conn) {
debug_mutex_lock(&conn->reference_time_mutex, 1000, 1);
int result = 0;
uint64_t time_difference;
int64_t frame_difference;
uint32_t frame_difference;
result = sanitised_source_rate_information(&frame_difference, &time_difference, conn);
int64_t timestamp_interval =
timestamp -
conn->reference_timestamp *
conn->output_sample_ratio; // we could be dealing with multiples of 44100 (nominally)
// debug(1, "Timestamp interval: %" PRId64 " frames with reference timestamp %" PRId64
// ".",timestamp_interval,conn->reference_timestamp);
uint64_t timestamp_interval_time;
uint64_t remote_time_of_timestamp;
if (timestamp_interval >= 0) {
uint32_t timestamp_interval = rtp_frame_offset(conn->reference_timestamp,timestamp);
if (timestamp_interval <= 44100*10) { // i.e. timestamp was really after the reference timestamp
timestamp_interval_time =
(timestamp_interval * time_difference) /
(frame_difference * conn->output_sample_ratio); // this is the nominal time, based on the
(frame_difference); // this is the nominal time, based on the
// fps specified between current and
// previous sync frame.
remote_time_of_timestamp = conn->remote_reference_timestamp_time +
timestamp_interval_time; // based on the reference timestamp time
// plus the time interval calculated based
// on the specified fps.
} else {
} else { // i.e. timestamp was actually after the reference timestamp
timestamp_interval = rtp_frame_offset(timestamp,conn->reference_timestamp); // fix the calculation
timestamp_interval_time =
((-timestamp_interval) * time_difference) /
(frame_difference * conn->output_sample_ratio); // this is the nominal time, based on the
(timestamp_interval * time_difference) /
(frame_difference); // this is the nominal time, based on the
// fps specified between current and
// previous sync frame.
remote_time_of_timestamp = conn->remote_reference_timestamp_time -
@@ -1105,12 +1101,12 @@ int frame_to_local_time(int64_t timestamp, uint64_t *time, rtsp_conn_info *conn)
return result;
}
int local_time_to_frame(uint64_t time, int64_t *frame, rtsp_conn_info *conn) {
int local_time_to_frame(uint64_t time, uint32_t *frame, rtsp_conn_info *conn) {
debug_mutex_lock(&conn->reference_time_mutex, 1000, 1);
int result = 0;
uint64_t time_difference;
int64_t frame_difference;
uint32_t frame_difference;
result = sanitised_source_rate_information(&frame_difference, &time_difference, conn);
// first, get from [local] time to remote time.
@@ -1129,10 +1125,10 @@ int local_time_to_frame(uint64_t time, int64_t *frame, rtsp_conn_info *conn) {
int64_t frame_interval = (time_interval * frame_difference) / time_difference;
if (remote_time >= conn->remote_reference_timestamp_time) {
// debug(1,"Frame interval is %" PRId64 " frames.",frame_interval);
*frame = (conn->reference_timestamp + frame_interval) * conn->output_sample_ratio;
*frame = (conn->reference_timestamp + frame_interval);
} else {
// debug(1,"Frame interval is %" PRId64 " frames.",-frame_interval);
*frame = (conn->reference_timestamp - frame_interval) * conn->output_sample_ratio;
*frame = (conn->reference_timestamp - frame_interval);
}
debug_mutex_unlock(&conn->reference_time_mutex, 3);
return result;