Apart from the obvious drawbacks of hardcoding, the drawback here was
that, if we subtracted 2 frames (instead of 2.6) from the target running
time, we'd request the next keyframe a bit too far into the future,
which would make our files split at the wrong position.
https://bugzilla.gnome.org/show_bug.cgi?id=797293
Flv does not support various channels in AAC stream format, for example
flvdemux detect an audio channels of 2(stereo) when the AAC really is 1(mono).
https://bugzilla.gnome.org/show_bug.cgi?id=797275
Flv does support changing the stream type and stream properties
after the headers were started to be written, and for example H264
codec_data changes can be supported.
https://bugzilla.gnome.org/show_bug.cgi?id=797256
For drop-frame framerates, when the expected next max timecode wraps
around at the end of the day, we have to subtract the offset of the
daily jam, otherwise we end up with a duration that's a few frames too
long.
https://bugzilla.gnome.org/show_bug.cgi?id=797270
This commit:
1. Reads the WebM and Matroska ContentEncryption subelements.
2. Creates a GST_PROTECTION event for each ContentEncryption, which
will be sent before pushing the first source buffer.
The DRM system id field in this event is set to GST_PROTECTION_UNSPECIFIED_SYSTEM_ID,
because it isn't specified neither by Matroska nor by the WebM spec.
3. Reads the protection information of encrypted Block/SimpleBlock and
extracts the IV and the partitioning format (subsamples).
4. Creates the metadata protection for each encrypted Block/SimpleBlock,
with those informations: KeyID (extracted from ContentEncryption element),
IV and partitioning format.
5. Adds a new caps for WebM encrypted content named "application/x-webm-enc",
with the following new fields:
"encryption-algorithm": The encryption algorithm used.
values: "None", "DES", "3DES", "Twofish", "Blowfish", "AES".
"encoding-scope": The field that describes which Elements have been modified.
Values: "frame", "codec-data", "next-content".
"cipher-mode": The cipher mode used in the encryption.
Values: "None", "CTR".
https://bugzilla.gnome.org/show_bug.cgi?id=765275
Strip ADTS headers if we detect any, apparently some Sony cameras
send AAC with ADTS headers. We could also change the stream-format
in the output caps, but that would be unexpected to pipeline builders
and would not exactly be backwards compatible.
qtdemux_update_streams() is only ever called after checking
`qtdemux->streams_aware` is TRUE. There is no need to check for that
condition again.
`qtdemux->streams_aware` is only modified when the demuxer is
hard-resetted, which is mutually exclusive with demuxing, so it cannot
be modified during the call.
https://bugzilla.gnome.org/show_bug.cgi?id=797191
Currently matroskademux does not emit no-more-pads until the first
Cluster is parsed, even though the Tracks have already been parsed and
from that point on there can be no more tracks.
This is important in MSE because the browser needs to know when the MSE
initialization segment has been completely parsed so that it can expose
the tracks to the user. Some applications depend on this been done
before they feed frames to the demuxer.
As a consequence, historically WebKit has relied on hacks such as
listening to the `pad-added` event, which made impossible to support
multiple tracks in the same file. Let's fix that.
https://bugzilla.gnome.org/show_bug.cgi?id=797187
This patch allows matroskademux to parse a second Tracks element,
erroring out if the tracks are not compatible (different number, type or
codec) and emitting new caps and tag events should they have changed.
https://bugzilla.gnome.org/show_bug.cgi?id=793333
This splits gst_matroska_demux_add_stream() into:
* gst_matroska_demux_parse_stream(): will read the Matroska bytestream
and fill a GstMatroskaTrackContext.
* gst_matroska_demux_parse_tracks(): will check there are no repeated
tracks.
* gst_matroska_demux_add_stream(): creates and sets up the pad for the
track.
https://bugzilla.gnome.org/show_bug.cgi?id=793333
This is necessary for MSE, where a new MSE initialization segment may be
appended at any point. These MSE initialization segments consist of an
entire WebM file until the first Cluster element (not included). [1]
Note that track definitions are ignored on successive headers, they must
match, but this is not checked by matroskademux (look for
`(!demux->tracks_parsed)` in the code).
Source pads are not altered when the new headers are read.
This patch has been splitted from the original patch from eocanha in [2].
[1] https://www.w3.org/TR/mse-byte-stream-format-webm/
[2] https://bug334082.bugzilla-attachments.gnome.org/attachment.cgi?id=362212https://bugzilla.gnome.org/show_bug.cgi?id=793333
The behaviour of split-now is to output the current GOP after
starting a new file.
The newly-added split-after signal will output the current GOP
to the old file if possible once a new GOP is opened.
https://bugzilla.gnome.org/show_bug.cgi?id=796982
For 59.94 FPS, it's common to set 60000 as timescale. For that
timescale, if the audio is late by as little as 0:00:00.000016666
(definitely less than one audio sample), lateness gets rounded to 1.
Added a safeguard that allows lateness up to 1 sample with the specific
trak's timescale, to make sure that values less than e.g. one audio
sample won't break the prefill mode. What will happen in this case is
that the audio will get squeezed back to the video's timestamp, which in
practice means that the audio will be 0.000016666 seconds early (with
the patch).
https://bugzilla.gnome.org/show_bug.cgi?id=797133
Accept wavpack correction streams (.wvc) on sink pad, so
that wavpackparse can also be used to packetise correction
streams.
Fix parsing of subblock ID tags - the higher bits are
flags and are not part of the ID. This resulted in
correction blocks not being recognised properly and
the output not having the right (correction) caps.
Currently, whenever we generate a 128-bit UID, we store it in a list and
return 0 if we ever encounter a collision. This is so mathematically
improbable that it's not worth checking for, so we can save memory and
time by not tracking the UID. Even if a collision happened, a list of
only 10 UIDs would be unlikely to detect it.
This article has a good description of how improbable a collision is:
https://en.wikipedia.org/wiki/Universally_unique_identifier#Collisionshttps://bugzilla.gnome.org/show_bug.cgi?id=797086
This patch clears the sample table whenever the demuxing of a new
fragment begins. This avoids increasing memory usage for long videos.
This behavior was already present when upstream_format_is_time; this
patch extends it to all push mode operation (e.g. Media Source
Extensions).
https://bugzilla.gnome.org/show_bug.cgi?id=796899
Both rtpmp4vpay and rtpmp4gpay support MPEG4 elementary streams. But
the most supported variant is the video-specific one (rtpmp4vpay),
therefore increase the rank of that one so that auto-plugging of
payloaders for MPEG4 elementary streams ends up picking that one
and not the generic one.
If we have cluster prev size (GStreamer muxer will write it by default),
we can go back to the previous cluster efficiently, but if we don't then
just search backwards until we find a cluster ebml identifier, like we
do when searching for clusters in the bisection loop.
Add property instead of hardcoding it in the code.
In some scenarios such as CCTV variable fps and extra long GOPs are
used to minimise storage space, for example. In those cases there might
not be any keyframes for many minutes, so provide a property to override
the max allowed distance.
https://bugzilla.gnome.org/show_bug.cgi?id=790696
When seeking in pull mode without an index (because there is no index
or the file is still being written to) we bisect to find the right
cluster to jump to. However, it's possible the cluster we found doesn't
start with a keyframe, which leads to decoding errors, so if we know
that the found cluster starts with a delta frame try to scan back to
previous clusters until we find one that starts with a keyframe or
we are back at the beginning. Theoretically it's possible that all
clusters but the first one do not start with a keyframe and the
keyframes are in the middle of clusters, but this is extremely
unusual, so we will cover this case with a basic sanity check.
This problem is especially problematic with content recorded with
dynamic GOP and FPS, where long GOP lengths and low FPS may cause a
large set of clusters to lack key frames. Playback would then be
started on a non-keyframe cluster, and the large number of such frames
would make the content impossible to decode fo a long stretch of time.
Based on patch by: Mats Lindestam <matslm@axis.com>
https://bugzilla.gnome.org/show_bug.cgi?id=790696
This is useful for reverse playback/trickmodes
without an index, and will also be useful in the
seek handler if we need to scan back to find a cluster
that starts with a keyframe.
https://bugzilla.gnome.org/show_bug.cgi?id=790696
This is an enum not a boolean, and a value of 2 signals
that the video is progressive, but we would mistakenly set
interlace-mode=mixed on the output caps.
https://bugzilla.gnome.org/show_bug.cgi?id=787206
On Linux, the kernel returns twice the size as it will allocate extra
space for accouting. We devides this value by two in order to ensure
that get/set value now match. This fixes the set buffer size validation
and allow having a nice warning when the size if surpassed and the
process does not have CAP_NET_ADMIN capabilities.
https://bugzilla.gnome.org/show_bug.cgi?id=727067
The udp buffer size is limited to a maximum of around 100K.
Some apps need to set the force bufsize for their own operation.
Use the SO_RCVBUFFORCE option in order to override the rmem_max limit
of linux kernel. Require user to have the CAP_NET_ADMIN privilege to
work.
Original patch from Kyungnam Bae <kyungnam.bae@lge.com>
https://bugzilla.gnome.org/show_bug.cgi?id=727067
