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32 commits

Author SHA1 Message Date
Edward Hervey
2762ead5ef mpegtsdemux: New PCR<=>Offset estimation code
This allows:
* Better duration estimation
* More accurate PCR location
* Overall more accurate running-time location and calculation

Location and values of PCR are recorded in groups (PCROffsetGroup)
with notable PCR/Offset observations in them (when bitrate changed
for example). PCR and offset are stored as 32bit values to
reduce memory usage (they are differences against that group's
first_{pcr|offset}.

Those groups each contain a global PCR offset (pcr_offset) which
indicates how far in the stream that group is.

Whenever new PCR values are observed, we store them in a sliding
window estimator (PCROffsetGroupCurrent).

When a reset/wrapover/gap is detected, we close the current group with
current values and start a new one (the pcr_offset of that new group
is also calculated).

When a notable change in bitrate is observed (+/- 10%), we record
new values in the current group. This is a compromise between
storing all PCR/offset observations and none, while at the same time
providing better information for running-time<=>offset calculation
in VBR streams.

Whenever a new non-contiguous group is start (due to seeking for example)
we re-evaluate the pcr_offset of each groups. This allows detecting as
quickly as possible PCR wrapover/reset.

When wanting to find the offset of a certain running-time, one can
iterate the groups by looking at the pcr_offset (which in essence *is*
the running-time of that group in the overall stream).
Once a group (or neighbouring groups if the running-time is between two
groups) is found, once can use the recorded values to find the most
accurate offset.

Right now this code is only used in pull-mode , but could also
be activated later on for any seekable stream, like live timeshift
with queue2.

Future improvements:
* some heuristics to "compress" the stored values in groups so as to keep
  the memory usage down while still keeping a decent amount of notable
  points.
* After a seek compare expected and obtained PCR/Offset and if the
  difference is too big, re-calculate position with newly observed
  values and seek to that more accurate position.

Note that this code will *not* provide keyframe-accurate seeking, but
will allow a much more accurate PCR/running-time/offset location on
any random stream.
For past (observed) values it will be as accurate as can be.
For future values it will be better than the current situation.
Finally the more you seek, the more accurate your positioning will be.
2013-09-28 13:15:43 +02:00
Edward Hervey
5017ba84a7 mpegtspacketizer: No longer use a private struct
These are not public headers, it just adds complexity for no reason
2013-09-28 13:15:43 +02:00
Edward Hervey
ca77865bce mpegtspacketizer: More AFC flags
I should have put those in a previous commit. sorry :(
2013-07-29 09:42:11 +02:00
Edward Hervey
8c60e42070 mpegtsdemux: Add more flag debugging for PES and TS packets
Helps with debugging issues. And also remove unused variable (opcr)

This will also allow us in the future to properly detect:
* random-access location (to enable keyframe observation and
  potentially seeking
* discont location (to properly handle resets)
* splice location (to properly handle new stream changes)
2013-07-26 08:17:17 +02:00
Edward Hervey
61b30175b3 mpegtsdemux: Remove unneeded variables
* packet.origts is no longer used since the PCR refactoring done ages ago
* known_packet_size is a duplicate of packet_size != 0
* caps was never used outside of the packetizer
2013-07-09 12:25:11 +02:00
Edward Hervey
f58f13e874 mpegtsdemux: Fix multiple-SI detection/parsing
We had two issues with the previous code:
1) We were badly handling PUSI-flagged packets. We were discarding the
   initial data (if pointer != 0) whereas we should have been accumulating
   it with the previous data (if there was a continuity of course).
   => First series of information loss
2) We were not checking whether there were more sections after the end
   of one (i.e. when the following byte was not a stuff byte).

This fixes those two issues.

Fixes #677443

https://bugzilla.gnome.org/show_bug.cgi?id=677443
2013-07-07 08:29:37 +02:00
Edward Hervey
1f2bb15618 mpegtsdemux: GstMpegTS => GstMpegTs 2013-07-03 14:00:58 +02:00
Edward Hervey
92edd82c86 mpegtsdemux: Switch to MPEG-TS SI library
* Only mpeg-ts section packetization remains.
* Improve code to detect duplicated sections as early as possible
* Add FIXME for various issues that need fixing (but are not regressions)

https://bugzilla.gnome.org/show_bug.cgi?id=702724
2013-07-03 09:17:25 +02:00
Edward Hervey
9fd7f1c082 mpegtspacketizer: Speedup packet parsing
Avoid using bitshifting where not needed.

Speeds up packet parsing by 3% (this is *the* hotspot of mpeg-ts elements).
2013-06-24 07:49:34 +02:00
Edward Hervey
0592bcc3c9 mpegtspacketizer: Better detect already seen section
In some cases (NIT on highly-populated DVB-C operator for example), there
will be more than one section emitted for the same subtable and version
number.

In order not to lose those updates for the same version number, we checked
against the CRC of the previous section we parsed.

The problem is that, while it made sure we didn't lose any information, it
also meant that if the same section came back (same version, same CRC) later
on we would re-process it, re-parse it and re-emit it.

This version improves on that by keeping a list of previously observed CRC
for identical PID/subtable/version-number and will only process sections if
they really were never seen in the past (as opposed to just before).

On a 30s clip, this brings down the number of NIT section parsing from 4541
down to 663.

https://bugzilla.gnome.org/show_bug.cgi?id=614479
2013-06-23 09:06:15 +02:00
Josep Torra
28a2902a7b tsdemux: fixes seeking in pull mode
Preserve the current segment and observations in pull mode seeks with
flushing.

https://bugzilla.gnome.org/show_bug.cgi?id=698050
2013-06-12 08:01:06 +02:00
Tim-Philipp Müller
9e1b75fda3 Fix FSF address
https://bugzilla.gnome.org/show_bug.cgi?id=687520
2012-11-04 00:09:59 +00:00
Edward Hervey
8b80114101 mpegts: Use G_GNUC_INTERNAL 2012-08-14 19:07:24 +02:00
Edward Hervey
4f55cc12ae tsdemux: Calculate pcr/time/offset separately per program
Avoids quite a few issues with multi-program streams
2012-08-14 19:05:48 +02:00
Edward Hervey
e2576f0e86 mpegtsdemux: Also parse TOT (Time Offset Section)
It's the same as TDT, except with descriptors at the end
2012-06-05 10:54:27 +02:00
Edward Hervey
f0867c7247 mpegtspacketizer: Avoid alloc/free where possible
Helps for streams with a lot of sections, like EIT
2012-06-05 10:54:26 +02:00
Edward Hervey
63f8b970af mpegtsbase/packetizer: Add CAT section handling
Allows reporting the global EMM
2012-06-05 10:54:25 +02:00
Edward Hervey
c6035d403c mpegtspacketizer: Avoid usage of GstBuffer internally
The overhead of creating/using 188 byte GstBuffer from GstAdapter
is too expensive.
We now peek the next packet, and provide a data/size which is only
valid until the packetizerpacket is cleared.

In addition, cleanup all the internal code to deal with that new
behaviour and remove double-checks which are no longer needed.

The section_length is now the corrected section_length (i.e. with
the additional 3 bytes).

Avoid using gst_adapter_prev_timestamp and instead track
the timestamp ourself.
2012-05-22 17:43:38 +02:00
Edward Hervey
6d01f5f1b3 mpegtspacketizer: Detect PCR wraparound in skew code
If the received PCR is going backwards (by a safe margin), include
that wraparound for further calculation.

https://bugzilla.gnome.org/show_bug.cgi?id=674536
2012-05-22 16:51:25 +02:00
Gil Pedersen
fcd8155d87 mpegtsdemux: port to 0.11
Fixes https://bugzilla.gnome.org/show_bug.cgi?id=674397
2012-04-20 11:25:31 +02:00
Sebastian Dröge
a1c291ebb6 mpegtsdemux: Revert to 0.10 state as this is unmergeable, also put it into the non-ported plugins again 2012-03-29 17:55:09 +02:00
Sebastian Dröge
860ccd414d Merge remote-tracking branch 'origin/0.10'
Conflicts:
	NEWS
	RELEASE
	common
	configure.ac
	docs/libs/gst-plugins-bad-libs-sections.txt
	docs/plugins/gst-plugins-bad-plugins.args
	docs/plugins/gst-plugins-bad-plugins.hierarchy
	docs/plugins/gst-plugins-bad-plugins.interfaces
	docs/plugins/inspect/plugin-adpcmdec.xml
	docs/plugins/inspect/plugin-adpcmenc.xml
	docs/plugins/inspect/plugin-assrender.xml
	docs/plugins/inspect/plugin-audiovisualizers.xml
	docs/plugins/inspect/plugin-autoconvert.xml
	docs/plugins/inspect/plugin-bayer.xml
	docs/plugins/inspect/plugin-bz2.xml
	docs/plugins/inspect/plugin-camerabin2.xml
	docs/plugins/inspect/plugin-celt.xml
	docs/plugins/inspect/plugin-dataurisrc.xml
	docs/plugins/inspect/plugin-debugutilsbad.xml
	docs/plugins/inspect/plugin-dtmf.xml
	docs/plugins/inspect/plugin-dtsdec.xml
	docs/plugins/inspect/plugin-dvbsuboverlay.xml
	docs/plugins/inspect/plugin-dvdspu.xml
	docs/plugins/inspect/plugin-faac.xml
	docs/plugins/inspect/plugin-faad.xml
	docs/plugins/inspect/plugin-gsm.xml
	docs/plugins/inspect/plugin-h264parse.xml
	docs/plugins/inspect/plugin-mms.xml
	docs/plugins/inspect/plugin-modplug.xml
	docs/plugins/inspect/plugin-mpeg2enc.xml
	docs/plugins/inspect/plugin-mpegdemux2.xml
	docs/plugins/inspect/plugin-mpegtsdemux.xml
	docs/plugins/inspect/plugin-mpegvideoparse.xml
	docs/plugins/inspect/plugin-mplex.xml
	docs/plugins/inspect/plugin-pcapparse.xml
	docs/plugins/inspect/plugin-rawparse.xml
	docs/plugins/inspect/plugin-rtpmux.xml
	docs/plugins/inspect/plugin-rtpvp8.xml
	docs/plugins/inspect/plugin-scaletempo.xml
	docs/plugins/inspect/plugin-schro.xml
	docs/plugins/inspect/plugin-sdp.xml
	docs/plugins/inspect/plugin-segmentclip.xml
	docs/plugins/inspect/plugin-shm.xml
	docs/plugins/inspect/plugin-videomaxrate.xml
	docs/plugins/inspect/plugin-videoparsersbad.xml
	docs/plugins/inspect/plugin-vp8.xml
	docs/plugins/inspect/plugin-y4mdec.xml
	ext/celt/gstceltdec.c
	ext/dts/gstdtsdec.c
	ext/modplug/gstmodplug.cc
	ext/opus/gstopusenc.c
	gst-libs/gst/video/gstbasevideocodec.c
	gst-libs/gst/video/gstbasevideocodec.h
	gst-libs/gst/video/gstbasevideodecoder.c
	gst-libs/gst/video/gstbasevideodecoder.h
	gst-libs/gst/video/gstbasevideoencoder.c
	gst-libs/gst/video/gstbasevideoencoder.h
	gst/adpcmdec/Makefile.am
	gst/audiovisualizers/gstbaseaudiovisualizer.c
	gst/h264parse/gsth264parse.c
	gst/mpegdemux/mpegtsparse.c
	gst/mpegtsdemux/mpegtsbase.c
	gst/mpegtsdemux/mpegtspacketizer.c
	gst/mpegtsdemux/mpegtsparse.c
	gst/mpegtsdemux/tsdemux.c
	gst/mpegtsdemux/tsdemux.h
	gst/mxf/mxfdemux.c
	gst/rawparse/gstaudioparse.c
	gst/videoparsers/gsth263parse.c
	gst/videoparsers/gsth264parse.c
	sys/d3dvideosink/d3dvideosink.c
	sys/decklink/gstdecklinksink.cpp
	sys/dvb/gstdvbsrc.c
	sys/shm/gstshmsrc.c
	sys/vdpau/h264/gstvdph264dec.c
	sys/vdpau/mpeg/gstvdpmpegdec.c
	tests/examples/opencv/gst_element_print_properties.c
	win32/common/config.h
2012-03-29 17:41:53 +02:00
Edward Hervey
416b10b991 mpegtspacketizer: Handle rollover in offset calculations 2012-03-05 12:46:13 +01:00
Edward Hervey
a4899af8d6 mpegtspacketizer: Offset calculation
Allows PCR<=>PTS<=>offset estimation/calculation
Right now the calculation is very naive, but can be extended later on
without disrupting the code in tsdemux/mpegtsbase
2012-03-01 18:15:51 +01:00
Edward Hervey
39cc29a7d2 mpegtspacketizer: clock fix and minor addition
* Don't take into account packets that arrived at the same time as
  previous ones for clock skew estimation
* Add convenience method for processing the next ts packet
2012-03-01 18:15:51 +01:00
Edward Hervey
4bc7cd04c1 mpegtspacketizer: Fix issues with skew code
* Always try to get a timestamp for the algorithm
* Remove dead variable
* Return proper default value
2012-02-24 17:47:38 +01:00
Thibault Saunier
6a8d2c45f6 mpegtspacketizer: Estimate clock skew and retimestamps buffers more precisly
Apply the EPTLA algotithm to estimate clock skew.
Reusing code from  -good/gst/rtpmanager/rtpjitterbuffer.c
2012-02-24 10:57:09 +01:00
Wim Taymans
21073e98cf port to new memory API 2012-01-25 14:51:25 +01:00
Edward Hervey
6abe2134bf tsdemux/tsparse: Port to 0.11
This is a naive port that somewhat works but is inefficient.
I need to rethink how to make the best out of GstMemory/GstBuffer
2011-10-12 18:06:16 +02:00
Janne Grunau
15391b29e1 mpegtsdemux: push based seeking based on PCR
buffer timestamps are converted to GstClockTime to cover pcr/pts wraps.
multiple pcr/pts wraps are handled with an index which ensures at most
a single pcr wraparound between two entries.
the last seen pcr is recorded to have a nearby index point for short seeks
resuming playback might be delayed if the postion is not a keyframe

TODO: replace manual packet scanning and parsing in the initial duration estimation
2011-06-07 20:50:34 +02:00
Janne Grunau
f89a0abca0 mpegtsdemux: create function for pcr parsing 2011-06-07 20:50:34 +02:00
Janne Grunau
22ecf13e42 mpegtsdemux: add MPEG TS demuxer rewrite from Edward Hervey
with contributions from Miquel Angel Farre Guiu and Zaheer Abbas Merali
2011-02-17 17:56:59 +01:00