This information is coded in a standard MP4 KindBox and utilizes the
scheme and values as per the DASH role scheme defined in MPEG-DASH.
Other schemes are technically allowed, but where multiple schemes
define the same concepts, the DASH scheme should be utilized.
Such flagging is additionally utilized by the DASH-IF CMAF ingest
specification, enabling an encoder to inform the following component
of the roles of the incoming media streams.
A test is added for this functionality in a similar manner to the
matroska test.
Signed-off-by: Jan Ekström <jan.ekstrom@24i.com>
There can only be a maximum of 255 entries in a tfrf tag, so using
more makes no sense; moreover, several size computations can overflow
in this case. Fix this by limiting it to 255.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Includes basic support for both the ISMV ('dfxp') and MP4 ('stpp')
methods. This initial version also foregoes fragmentation support
in case the built-in sample squashing is to be utilized, as this
eases the initial review.
Additionally, add basic tests for both muxing modes in MP4.
Signed-off-by: Jan Ekström <jan.ekstrom@24i.com>
"frag_start" is redundant, and every occurance can be replaced with cluster[0].dts - start_dts
The proof of no behaviour changes: (All line number below is based on commit bff7d662d7)
"frag_start" is read at 4 place (with all possible call stacks):
mov_write_packet
...
mov_flush_fragment
mov_write_moof_tag
mov_write_moof_tag_internal
mov_write_traf_tag
mov_write_tfxd_tag (#1)
mov_write_tfdt_tag (#2)
mov_add_tfra_entries (#3)
mov_write_sidx_tags
mov_write_sidx_tag (#4)
mov_write_trailer
mov_auto_flush_fragment
mov_flush_fragment
... (#1#2#3#4)
mov_write_sidx_tags
mov_write_sidx_tag (#4)
shift_data
compute_sidx_size
get_sidx_size
mov_write_sidx_tags
mov_write_sidx_tag (#4)
All read happens in "mov_write_trailer" and "mov_write_moof_tag". So we need to prove no behaviour change in these two
functions.
Condition 1: for every track that have "trk->entry == 0", trk->frag_start == trk->track_duration.
Condition 2: for every track that have "trk->entry > 0", trk->frag_start == trk->cluster[0].dts - trk->start_dts.
Definition 1: "Before flush" means just before the invocation of "mov_flush_fragment", except for the auto-flush case in
"mov_write_single_packet", which means before L5934.
Lemma 1: If Condition 1 & 2 is true before flush, Condition 1 & 2 is still true after "mov_flush_fragment" returns.
Proof:
No update to the tracks that have "trk->entry == 0" before flushing, so we only consider tracks that have "trk->entry > 0":
Case 1: !moov_written and moov will be written in this iteration
trk->entry = 0 L5366
trk->frag_start == trk->cluster[0].dts - trk->start_dts Lemma condition
trk->frag_start += trk->start_dts + trk->track_duration - trk->cluster[0].dts; L5363
So trk->entry == 0 && trk->frag_start == trk->track_duration
Case 2: !moov_written and moov will NOT be written in this iteration
nothing changed
Case 3: moov_written
trk->entry = 0 L5445
trk->frag_start == trk->cluster[0].dts - trk->start_dts Lemma condition
trk->frag_start += trk->start_dts + trk->track_duration - trk->cluster[0].dts; L5444
So trk->entry == 0 && trk->frag_start == trk->track_duration
Note that trk->track_duration may be updated for the tracks that have "trk->entry > 0" (mov_write_moov_tag will
update track_duration of "tmcd" track, but it must have 1 entry). But in all case, trk->frag_start is also updated
to consider the new value.
Lemma 2: If Condition 1 & 2 is true before "ff_mov_write_packet" invocation, Condition 1 & 2 is still true after it returns.
Proof:
Only the track corresponding to the pkt is updated, and no update to relevant variables if trk->entry > 0 before invocation.
So we only need to prove "trk->frag_start == trk->cluster[0].dts - trk->start_dts" after trk->entry increase from 0 to 1.
Case 1: trk->start_dts == AV_NOPTS_VALUE
Case 1.1: trk->frag_discont && use_editlist
trk->cluster[0].dts = pkt->dts at L5741
trk->frag_start = pkt->pts at L5785
trk->start_dts = pkt->dts - pkt->pts at L5786
So trk->frag_start == trk->cluster[0].dts - trk->start_dts
Case 1.2: trk->frag_discont && !use_editlist
trk->cluster[0].dts = pkt->dts at L5741
trk->frag_start = pkt->dts at L5790
trk->start_dts = 0 at L5791
So trk->frag_start == trk->cluster[0].dts - trk->start_dts
Case 1.3: !trk->frag_discont
trk->cluster[0].dts = pkt->dts at L5741
trk->frag_start = 0 init
trk->start_dts = pkt->dts at L5779
So trk->frag_start == trk->cluster[0].dts - trk->start_dts
Case 2: trk->start_dts != AV_NOPTS_VALUE
Case 2.1: trk->frag_discont
trk->cluster[0].dts = pkt->dts at L5741
trk->frag_start = pkt->dts - trk->start_dts at L5763
So trk->frag_start == trk->cluster[0].dts - trk->start_dts
Case 2.2: !trk->frag_discont
trk->cluster[0].dts = trk->start_dts + trk->track_duration at L5749
trk->track_duration == trk->frag_start Lemma condition
So trk->frag_start == trk->cluster[0].dts - trk->start_dts
Lemma 3: Condition 1 & 2 is true in all case before and after "ff_mov_write_packet" invocation, before flush and after
"mov_flush_fragment" returns.
Proof: All updates to relevant variable happen either in "ff_mov_write_packet", or during flush. And Condition 1 & 2
is true initially. So with lemma 1 & 2, we can prove this use induction.
Noticed that all read of "frag_start" only happen in "trk->entry > 0" branch. Now we need to prove Condition 2 is true
before each read.
Because no update to variables relevant to Condition 2 between "before flush" and "mov_write_moof_tag" invocation, we
can conclude Condition 2 is true before every invocation of "mov_write_moof_tag". No behaviour change in
"mov_write_moof_tag" is proved.
In "mov_write_trailer", No update to relevant variables after the last flush and before the invocation of
"mov_write_sidx_tag". So no behaviour change to "mov_write_trailer" is proved.
Q.E.D.
Signed-off-by: Hu Weiwen <sehuww@mail.scut.edu.cn>
Signed-off-by: Martin Storsjö <martin@martin.st>
track->mdat_buf can be not NULL while the track is still empty if the
last packet write failed.
Signed-off-by: Hu Weiwen <sehuww@mail.scut.edu.cn>
Signed-off-by: Martin Storsjö <martin@martin.st>
If autoflushing on a new packet (e.g. due to the frag_every_frame
flag being set), there's no samples to be written in the new fragment,
so we can't overwrite the track duration in order to make it line
up with the next packet to be written.
Signed-off-by: Martin Storsjö <martin@martin.st>
The child_class_next API relied on different (de)muxers to use
different AVClasses; yet this API has been replaced by
child_class_iterate.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
There are cases where using 1000 as the MP4 timescale is not
accurate enough, for example when one needs sample-accurate audio
handling.
This adds a new AVOption to the MOV/MP4 muxer to override the
movie timescale, but it still defaults to 1000 to maintain current
default behavior.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
This is possible now that the next-API is gone.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Signed-off-by: James Almer <jamrial@gmail.com>
Deprecated in ddef3d902f.
(The reference file of the mov-zombie test needed to be updated, because
a rotate metadata tag is no longer exported; the side-data is of course
still present.)
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>
Don't blindly copy all bytes in extradata past ChannelMappingFamily. Instead
check if ChannelMappingFamily is not 0 and then only write the correct amount
of bytes from ChannelMappingTable, as defined in the spec[1].
Fixes part of ticket #9190.
[1] https://opus-codec.org/docs/opus_in_isobmff.html#4.3.2
Signed-off-by: James Almer <jamrial@gmail.com>
And make it const, so the caller doesn't attempt to change it.
ff_get_muxer_ts_offset() should be used to get the muxer timestamp offset.
Signed-off-by: James Almer <jamrial@gmail.com>
These made sense before 3ebf449766
when the creation of these boxes was specifically requested by the
user, but now they have become unnecessary as they are just like
many other boxes: If the input has the information required, they
are written, otherwise they are not.
They were moved to verbose verbosity level (which happens to be
the last level still relatively usable), and now appear either once
(normal MP4 muxing), or thrice (with the faststart flag set) in
any normal MP4 usage, without giving much useful information. Thus,
remove them in their current form.
If the edit lists remove parts of the output timeline, or add a
delay to it, this should be included in the mvhd/tkhd/mdhd durations,
which should correspond to the edit lists.
For tracks starting with pts < 0, the edit list trims out the segment
before pts=0. For tracks starting with pts > 0, a delay element is
added in the edit list, delaying the start of the track data.
In both cases, the practical effect is that the post-edit output
is as if the track had started with pts = 0. Thus calculate the range
from pts=0 to end_pts, for the purposes of mvhd/tkhd/mdhd, unless
edit lists explicitly are disabled.
mov_write_edts_tag needs to operate on the actual pts duration of
the track samples, not the duration that already takes the edit
list effect into account.
Signed-off-by: Martin Storsjö <martin@martin.st>
The 'alac' identifier has been registered to ISO and thus towards
ISOBMFF at the MP4 registration authority. The existing non-MOV
mux mode matches the official ALAC-in-MP4 specification.
The buffers used when fragmented output is enabled have up until now not
been freed in the deinit function; they leak e.g. if one errors out of
mov_write_trailer() before one reaches the point where they are normally
written out and freed. This can e.g. happen if allocating new vos_data
fails at the beginning of mov_write_trailer().
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Otherwise the old data leaks whenever extradata needs to be rewritten
(e.g. when encoding FLAC with our encoder that sends an updated
extradata packet at the end).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
When remuxing an rtp hint stream (or any stream with the tag "rtp "),
the mov muxer treats this as one of the rtp hint tracks it creates
internally when ordered to do so; yet this track lacks the
AVFormatContext for the hinting rtp muxer, leading to segfaults in
mov_write_udta_sdp() if a "trak" atom is written for this stream; if not,
the stream's codecpar is freed by mov_free() as if the mov muxer owned
it (it does for the internally created "rtp " tracks), but without
resetting st->codecpar, leading to double-frees lateron. This commit
therefore ignores said tag which makes rtp hint streams unremuxable.
This fixes tickets #8181 and #8186.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
There are two possible kinds of timecode tracks (with tag "tmcd") in the
mov muxer: Tracks created internally by the muxer and timecode tracks
sent by the user. If any of the latter exists, the former are
deactivated. The former all belong to another track, the source
track; the latter don't have a source track set, but the index of the
source track is initially zeroed by av_mallocz_array(). This is a
problem since 3d894db700cc1e360a7a75ab9ac8bf67ac6670a3: Said commit added
a function that calculates the duration of tracks and the duration of
timecode tracks is calculated by rescaling the duration (calculated by
the very same function) of the source track. This gives an infinite
recursion if the first track (the one that will be treated as source
track for all timecode tracks) is a timecode track itself, leading to a
stack overflow.
This commit fixes this by not using the nonexistent source track
when calculating the duration of timecode tracks not created internally
by the mov muxer.
Reviewed-by: Martin Storsjö <martin@martin.st>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
If the average bit rate cannot be calculated, such as in the case
of streamed fragmented mp4, utilize various available parameters
in priority order.
Tests are updated where the esds or btrt or ISML manifest boxes'
output changes.
This is utilized by various media ingests to figure out the bit
rate of the content you are pushing towards it, so write it for
video, audio and subtitle tracks in case at least one nonzero value
is available. It is only mentioned for timed metadata sample
descriptions in QTFF, so limit it only to ISOBMFF (MODE_MP4) mode.
Updates the FATE tests which have their results changed due to the
20 extra bytes being written per track.
Limin Wang
Jan Ekström
Derek Buitenhuis
Andreas Rheinhardt
Hu Weiwen
Martin Storsjö
Vadym Bezdushnyi
Joel Linn
Michael Niedermayer
Justin Ruggles
James Almer
Andreas Rheinhardt
Anton Khirnov
Jan Ekström
Leo Izen