[FFmpeg-cvslog] rtmpproto: Add getStreamLength call to query duration
Uwe L. Korn
git at videolan.org
Fri Oct 17 15:39:36 CEST 2014
ffmpeg | branch: master | Uwe L. Korn <uwelk at xhochy.com> | Tue Oct 14 17:16:21 2014 +0200| [e65c776d18dc14df8a279e017760862f9fc8763b] | committer: Martin Storsjö
rtmpproto: Add getStreamLength call to query duration
In (non-live) streams with no metadata, the duration of a stream can
be retrieved by calling the RTMP function getStreamLength with the
playpath. The server will return a positive duration upon the request if
the duration is known, otherwise either no response or a duration of 0
will be returned.
Signed-off-by: Martin Storsjö <martin at martin.st>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=e65c776d18dc14df8a279e017760862f9fc8763b
---
libavformat/rtmpproto.c | 106 +++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 106 insertions(+)
diff --git a/libavformat/rtmpproto.c b/libavformat/rtmpproto.c
index 44a9a0d..87d79bf 100644
--- a/libavformat/rtmpproto.c
+++ b/libavformat/rtmpproto.c
@@ -123,6 +123,7 @@ typedef struct RTMPContext {
int listen; ///< listen mode flag
int listen_timeout; ///< listen timeout to wait for new connections
int nb_streamid; ///< The next stream id to return on createStream calls
+ double duration; ///< Duration of the stream in seconds as returned by the server (only valid if non-zero)
char username[50];
char password[50];
char auth_params[500];
@@ -679,6 +680,30 @@ static int gen_delete_stream(URLContext *s, RTMPContext *rt)
}
/**
+ * Generate 'getStreamLength' call and send it to the server. If the server
+ * knows the duration of the selected stream, it will reply with the duration
+ * in seconds.
+ */
+static int gen_get_stream_length(URLContext *s, RTMPContext *rt)
+{
+ RTMPPacket pkt;
+ uint8_t *p;
+ int ret;
+
+ if ((ret = ff_rtmp_packet_create(&pkt, RTMP_SOURCE_CHANNEL, RTMP_PT_INVOKE,
+ 0, 31 + strlen(rt->playpath))) < 0)
+ return ret;
+
+ p = pkt.data;
+ ff_amf_write_string(&p, "getStreamLength");
+ ff_amf_write_number(&p, ++rt->nb_invokes);
+ ff_amf_write_null(&p);
+ ff_amf_write_string(&p, rt->playpath);
+
+ return rtmp_send_packet(rt, &pkt, 1);
+}
+
+/**
* Generate client buffer time and send it to the server.
*/
static int gen_buffer_time(URLContext *s, RTMPContext *rt)
@@ -2044,11 +2069,19 @@ static int handle_invoke_result(URLContext *s, RTMPPacket *pkt)
if ((ret = gen_publish(s, rt)) < 0)
goto fail;
} else {
+ if (rt->live != -1) {
+ if ((ret = gen_get_stream_length(s, rt)) < 0)
+ goto fail;
+ }
if ((ret = gen_play(s, rt)) < 0)
goto fail;
if ((ret = gen_buffer_time(s, rt)) < 0)
goto fail;
}
+ } else if (!strcmp(tracked_method, "getStreamLength")) {
+ if (read_number_result(pkt, &rt->duration)) {
+ av_log(s, AV_LOG_WARNING, "Unexpected reply on getStreamLength()\n");
+ }
}
fail:
@@ -2450,6 +2483,70 @@ static int rtmp_close(URLContext *h)
}
/**
+ * Insert a fake onMetadata packet into the FLV stream to notify the FLV
+ * demuxer about the duration of the stream.
+ *
+ * This should only be done if there was no real onMetadata packet sent by the
+ * server at the start of the stream and if we were able to retrieve a valid
+ * duration via a getStreamLength call.
+ *
+ * @return 0 for successful operation, negative value in case of error
+ */
+static int inject_fake_duration_metadata(RTMPContext *rt)
+{
+ // We need to insert the metdata packet directly after the FLV
+ // header, i.e. we need to move all other already read data by the
+ // size of our fake metadata packet.
+
+ uint8_t* p;
+ // Keep old flv_data pointer
+ uint8_t* old_flv_data = rt->flv_data;
+ // Allocate a new flv_data pointer with enough space for the additional package
+ if (!(rt->flv_data = av_malloc(rt->flv_size + 55))) {
+ rt->flv_data = old_flv_data;
+ return AVERROR(ENOMEM);
+ }
+
+ // Copy FLV header
+ memcpy(rt->flv_data, old_flv_data, 13);
+ // Copy remaining packets
+ memcpy(rt->flv_data + 13 + 55, old_flv_data + 13, rt->flv_size - 13);
+ // Increase the size by the injected packet
+ rt->flv_size += 55;
+ // Delete the old FLV data
+ av_free(old_flv_data);
+
+ p = rt->flv_data + 13;
+ bytestream_put_byte(&p, FLV_TAG_TYPE_META);
+ bytestream_put_be24(&p, 40); // size of data part (sum of all parts below)
+ bytestream_put_be24(&p, 0); // timestamp
+ bytestream_put_be32(&p, 0); // reserved
+
+ // first event name as a string
+ bytestream_put_byte(&p, AMF_DATA_TYPE_STRING);
+ // "onMetaData" as AMF string
+ bytestream_put_be16(&p, 10);
+ bytestream_put_buffer(&p, "onMetaData", 10);
+
+ // mixed array (hash) with size and string/type/data tuples
+ bytestream_put_byte(&p, AMF_DATA_TYPE_MIXEDARRAY);
+ bytestream_put_be32(&p, 1); // metadata_count
+
+ // "duration" as AMF string
+ bytestream_put_be16(&p, 8);
+ bytestream_put_buffer(&p, "duration", 8);
+ bytestream_put_byte(&p, AMF_DATA_TYPE_NUMBER);
+ bytestream_put_be64(&p, av_double2int(rt->duration));
+
+ // Finalise object
+ bytestream_put_be16(&p, 0); // Empty string
+ bytestream_put_byte(&p, AMF_END_OF_OBJECT);
+ bytestream_put_be32(&p, 40); // size of data part (sum of all parts below)
+
+ return 0;
+}
+
+/**
* Open RTMP connection and verify that the stream can be played.
*
* URL syntax: rtmp://server[:port][/app][/playpath]
@@ -2656,6 +2753,7 @@ reconnect:
rt->received_metadata = 0;
rt->last_bytes_read = 0;
rt->server_bw = 2500000;
+ rt->duration = 0;
av_log(s, AV_LOG_DEBUG, "Proto = %s, path = %s, app = %s, fname = %s\n",
proto, path, rt->app, rt->playpath);
@@ -2714,6 +2812,14 @@ reconnect:
if (rt->has_video) {
rt->flv_data[4] |= FLV_HEADER_FLAG_HASVIDEO;
}
+
+ // If we received the first packet of an A/V stream and no metadata but
+ // the server returned a valid duration, create a fake metadata packet
+ // to inform the FLV decoder about the duration.
+ if (!rt->received_metadata && rt->duration > 0) {
+ if ((ret = inject_fake_duration_metadata(rt)) < 0)
+ goto fail;
+ }
} else {
rt->flv_size = 0;
rt->flv_data = NULL;
More information about the ffmpeg-cvslog
mailing list