The constants used in the decoder used floating point precision,
and this caused different values to be generated on different
architectures. Additionally on big endian machines, the fate test
would output bytes in native order, which is different from the one
hardcoded in the test.
So, eradicate floating point numbers and use fixed point (32.32)
arithmetics everywhere, replacing constants with precomputed integer
values, and force the pixel format output to be the same in the fate
test.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
This matrix needs to be applied after all others have (currently only
display matrix from trak), but cannot be handled in movie box, since
streams are not allocated yet. So store it in main context, and apply
it when appropriate, that is after parsing the tkhd one.
Fate tests are updated accordingly.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
This also fixes a minor bug introduced in the codecpar conversion, where
the termination condition for extracting the extradata does not match
the actual extradata setting code. As a result, the packet durations
made up by lavf go back to their values before the codecpar conversion.
That is of little consequence since that code should eventually be
dropped completely.
The current sample comes from an older version of the codec, which
supports a single output mode, so rename it accordingly.
Add tests for the new pixel formats.
Currently, AVStream contains an embedded AVCodecContext instance, which
is used by demuxers to export stream parameters to the caller and by
muxers to receive stream parameters from the caller. It is also used
internally as the codec context that is passed to parsers.
In addition, it is also widely used by the callers as the decoding (when
demuxer) or encoding (when muxing) context, though this has been
officially discouraged since Libav 11.
There are multiple important problems with this approach:
- the fields in AVCodecContext are in general one of
* stream parameters
* codec options
* codec state
However, it's not clear which ones are which. It is consequently
unclear which fields are a demuxer allowed to set or a muxer allowed to
read. This leads to erratic behaviour depending on whether decoding or
encoding is being performed or not (and whether it uses the AVStream
embedded codec context).
- various synchronization issues arising from the fact that the same
context is used by several different APIs (muxers/demuxers,
parsers, bitstream filters and encoders/decoders) simultaneously, with
there being no clear rules for who can modify what and the different
processes being typically delayed with respect to each other.
- avformat_find_stream_info() making it necessary to support opening
and closing a single codec context multiple times, thus
complicating the semantics of freeing various allocated objects in the
codec context.
Those problems are resolved by replacing the AVStream embedded codec
context with a newly added AVCodecParameters instance, which stores only
the stream parameters exported by the demuxers or read by the muxers.
The timebase change in the zmbv-8bit test is due to the fact that
previously the timebase string was evaluated as floating point, then
converted to a rational. After this commit, the timebase is passed
directly as is.
