This will be used to select the appropriate decoders. We also only attach the
GstVideoCodecAlphaMeta if the AlphaMode element is set, this is to stay on the
safe side and mimic what browsers (verified in Firefox and Chromium code) do.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/968>
The old code had a couple of issues that all lead to potential memory
safety bugs.
- Use a constant for the Wavpack4Header size instead of using sizeof.
It's written out into the data and not from the struct and who knows
what special alignment/padding requirements some C compilers have.
- gst_buffer_set_size() does not realloc the buffer when setting a
bigger size than allocated, it only allows growing up to the maximum
allocated size. Instead use a GstAdapter to collect all the blocks
and take out everything at once in the end.
- Check that enough data is actually available in the input and
otherwise handle it an error in all cases instead of silently
ignoring it.
Among other things this fixes out of bounds writes because the code
assumed gst_buffer_set_size() can grow the buffer and simply wrote after
the end of the buffer.
Thanks to Natalie Silvanovich for reporting.
Fixes https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/issues/859
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/902>
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
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
TOC support in mastroskamux has been deactivated for a couple of years. This commit updates it to recent GstToc evolutions and introduces toc unit tests for both matroska-mux and matroska-demux.
There are two UIDs for Chapters in Matroska's specifications:
- The ChapterUID is a mandatory unsigned integer which internally refers to a given chapter. Except for title & language which use dedicated fields, this UID can also be used to add tags to the Chapter. The tags come in a separate section of the container.
- The ChapterStringUID is an optional UTF-8 string which also uniquely refers to a chapter but from an external perspective. It can act as a "WebVTT cue identifier" which "can be used to reference a specific cue, for example from script or CSS".
During muxing, the ChapterUID is generated and checked for unicity, while the ChapterStringUID receives the user defined UID. In order to be able to refer to chapters from the tags section, we maintain an internal Toc tree with the generated ChapterUID.
When demuxing, the ChapterStringUIDs (if available) are assigned to the GstTocEntries UIDs and an internal toc mimicking the toc is used to keep track of the ChapterUIDs and match the tags with the appropriate GstTocEntries.
https://bugzilla.gnome.org/show_bug.cgi?id=790686
... and forward colorimetry to downstream. The Colour element describes
various color information (similar to 'colr' box in isobmff).
Note that, due to the comparatively limited syntax for color information
in vpx codecs, the color information in mkv/wemb container level
should be used for sophisticated color handling (e.g., HDR video).
https://bugzilla.gnome.org/show_bug.cgi?id=790023
Re-arrange order of index entry struct members to avoid padding
bytes in the middle of the struct, thus potentially reducing the
overall size of the struct and reducing memory used by the index.
On Linux x86_64 the size goes down from 32 bytes to 24 bytes for
each index entry.
Implement support for the packed video formats WebM
uses, not all the values that Matroska might use.
In practice, it's really hard to find any samples in the
wild of any.
Supported in both the muxer and demuxer.
New tags can be found on different parts of the file, so this patch
keeps the stream taglists around for the life cycle of the pad
and adds those new tags as found. Then a new tag is found, the
pad's is marked with a tags changed flag, making the element push
a new tag event on the next check. Before this, we were sending
only the newly found tags, as the element was losing its taglist
when pushing the event.
This is meant to be so (https://wiki.xiph.org/MatroskaOpus - while
it is marked as a draft, this part was confirmed to be correct on
IRC), and allows one to determine whether a demuxed stream is
multistream or not, and thus set the multistream caps field
accordingly. In turn, this means downstream does not have to guess.
https://bugzilla.gnome.org/show_bug.cgi?id=740744
* Also expose unknown tags as key=value pairs.
* Arrange tag map in the same order tags are listed in Matroska spec, leaving
unmapped tags as comments.
* More specific TODOs.
* Remove duplicate DATE define.
Fixes#682615
Depends on #682524
* Reads TargetType and TargetTypeValue from a Tag.
* After Tag is completely read, processes taglist, substituting some of the
tags depending on target type value and the presence of video/subtitle streams.
* Supports reading two new simpletags - PART_NUMBER and TOTAL_PARTS
Depends on #682448Fixes#682524
Support for TAG_IMAGE and TAG_ATTACHMENT is commented out; this requires caps
on buffers which is gone from 0.11.
Segment handling in the demuxer is a bit complex; I added some FIXME comments
in places where I'm not yet sure if I ported correctly.
Since matroskademux will attempt to push unaligned buffers,
downstream might have trouble with those, especially if downstream
uses ORC, such as audioconvert.
Ensure we push buffers aligned to the basic type at least for
those raw buffers.
https://bugzilla.gnome.org/show_bug.cgi?id=659798
AUTHOR only existed in an old version of the spec and ARTIST is
the new replacement for this. We are still reading both to still
be compatible with old files.
Fixes bug #644875.
Before, vp8dec had no option but to decode all frames even if some/all
of them would be late. With this change, performance when keyframes are
frequent is helped a great deal. On my Thinkpad X60s, decoding a 20 s
1080p sunflower encode with keyframes every 10 frames went from taking
42 s with 5 frames shown to 21 s with 15 frames shown (still slow
enough to count by hand). When keyframes are more sparse, you will
still be able to catch up eventually, but the results won't be as
noticable.
