Fixes crash when writting trailer without any previous packets.

cbs_mpeg2_free_slice() calls av_buffer_unref() on extra_information_ref,
meaning allocating with av_malloc() was not the intention.
Signed-off-by: James Almer <jamrial@gmail.com>

Up until now, things that are merely unsupported by cbs_mpeg2 have been
declared to be invalid input. This has been changed.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

The frame_centre_horizontal/vertical_offset values contained in picture
display extensions are actually signed values (i.e. it is possible to
indicate that the display device should add black bars/pillars).

The files sony-ct3.bs and tcela-6.bits (which are both used in fate
tests for mpeg2_metadata) contain picture display extensions; the former
even contains a negative frame_centre_vertical_offset. Fortunately, the
old code did not damage the picture display extensions when one did a
cycle of reading and writing. For the same reason the fate tests needn't
be updated either.

Furthermore these fields now use the trace output for matrices.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

MPEG-2 contains several elements that mustn't be zero according to the
specifications: horizontal/vertical_size_value, aspect_ratio_information,
frame_rate_code, the quantiser matrices, the colour_description
elements, picture_coding_type, the f_code[r][s] values and
quantiser_scale_code. It is now checked that the invalid values don't
occur.

The colour_description elements are treated specially in this regard:
Given that there are files in the wild which use illegal values for the
colour_description elements (some of them created by mpeg2_metadata),
they will be corrected to the value meaning "unknown" (namely 2) during
reading. This has been done in such a way that trace_headers will
nevertheless report the original value, together with a message about
the fixup.

Furthermore, the trace_headers output of user_data has been beautified.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

At present, if the outer stream extradata is empty but first packet
has extradata as a side data element, then only the first segment's
muxer instance may be able to extract this side data and use it.
For all other segments, extradata in packet side data could be missing
and generated segments may be invalid or unplayable in some apps
e.g. for an ADTS AAC stream segmented to MP4, the adtstoasc BSF will
add extradata to the first packet. The MOV muxer for the first segment
will add this to codecpar for the inner stream and write
Decoder Specific Information within the esds box. For other segments,
their esds' will not have this decSpecificInfo and they can't be opened
in Quicktime player or by services like nginx-vod-module.

native and tensorflow is exclusive, so change the type from
flags to int.
Signed-off-by: Jun Zhao <barryjzhao@tencent.com>

sr didn't enable the slice threading, so remove the flag
Signed-off-by: Jun Zhao <barryjzhao@tencent.com>

Document eld_v2 option for libfdk_aac encoder.
Signed-off-by: Jun Zhao <barryjzhao@tencent.com>

Document checkheaders/alltools and consistency fixes
Signed-off-by: Jun Zhao <barryjzhao@tencent.com>

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Fixes: Timeout (54sec -> 188ms)
Fixes: 14585/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_DIRAC_fuzzer-5649933052411904

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: Michael Niedermayer <michael@niedermayer.cc>

Fixes: signed integer overflow: -1877966852 + -469491713 cannot be represented in type 'int'
Fixes: 14561/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_TRUEMOTION2_fuzzer-5167608359288832

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: Michael Niedermayer <michael@niedermayer.cc>

Fixes: Timeout (14sec -> 9sec)
Fixes: 13398/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_FFV1_fuzzer-5664106709778432

decode_line() becomes 1% faster for fate/vsynth2-ffv1.avi
for another fate sample there is a 0.5% speedup
the effect should be bigger for files with "flat" colored areas
the new faster branch is used in 97-100% of the cases in fate samples
compared to the older more complex (which i tested)

vsynth3-ffv1-v3-bgr0.avi had the lowest percentual useage of about 97%

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: James Almer <jamrial@gmail.com>

Explain that the default Lanczos filter parameter is 3 and that it can be
changed by the param0 option.
Signed-off-by: Werner Robitza <werner.robitza@gmail.com>

To ensure the custom allocator is effectively used.
Signed-off-by: James Almer <jamrial@gmail.com>

Signed-off-by: James Almer <jamrial@gmail.com>

Slightly modified by Marton Balint to produce valid json as well.
Signed-off-by: Marton Balint <cus@passwd.hu>

In function ff_dct_unquantize_mpeg2_intra_mmi,
addr0 shoudn't be changed before storage operation.
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Fixes: Timeout (23sec -> 0.5sec)
Fixes: 14329/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_LSCR_fuzzer-5679252923482112

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegReviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Marton Balint <cus@passwd.hu>

Fixes infinte loop with -vf loop=loop=1 and also fixes looping when the input
is less frames than the specified loop size.

Possible regressions since ef1aadff.
Signed-off-by: Marton Balint <cus@passwd.hu>

Fixes Coverity CID 1441461.
Signed-off-by: Marton Balint <cus@passwd.hu>

Fixes Coverity CID 1441460.
Signed-off-by: Marton Balint <cus@passwd.hu>

Fixes a regression introduced in dbfd0429.
Signed-off-by: Marton Balint <cus@passwd.hu>