Signed-off-by: Marth64 <marth64@proxyid.net>
Raw Captions With Time (RCWT) is a format native to ccextractor, a commonly
used open source tool for processing 608/708 closed caption (CC) sources.
It can be used to archive the original, raw CC bitstream and to produce
a source file file for later CC processing or conversion. As a result,
it also allows for interopability with ccextractor for processing CC data
extracted via ffmpeg. The format is simple to parse and can be used
to retain all lines and variants of CC.
A free specification of RCWT can be found here:
https://github.com/CCExtractor/ccextractor/blob/master/docs/BINARY_FILE_FORMAT.TXT
This muxer implements the specification as of 01/05/2024, which has
been stable and unchanged for 10 years as of this writing.
This muxer will have some nuances from the way that ccextractor muxes RCWT.
No compatibility issues when processing the output with ccextractor
have been observed as a result of this so far, but mileage may vary
and outputs will not be a bit-exact match.
Specifically, the differences are:
(1) This muxer will identify as "FF" as the writing program identifier, so
as to be honest about the output's origin.
(2) ffmpeg's MPEG-1/2, H264, HEVC, etc. decoders extract closed captioning
data differently than ccextractor from embedded SEI/user data.
For example, DVD captioning bytes will be translated to ATSC A53 format.
This allows ffmpeg to handle 608/708 in a consistant way downstream.
This is a lossless conversion and the meaningful data is retained.
(3) This muxer will not alter the extracted data except to remove invalid
packets in between valid CC blocks. On the other hand, ccextractor
will by default remove mid-stream padding, and add padding at the end
of the stream (in order to convey the end time of the source video).
This was accidentally removed in a prior revision of the series,
alongside the corresponding (separate) version bump. Instead coalesce it
into the follow-up commit's entry, since that's the lowest version
actually supporting the new fields.
Move section to the top of the file, use table in place of subsection
to list the comprising muxers, and show media type information and
extensions in the item entry names.
To allow adding proper negotiation, in particular, to fftools.
These values will simply be negotiated downstream for YUV formats, and
ignored otherwise.
Motivated by YUVJ removal. This change will allow full negotiation
between color ranges and matrices as needed. By default, all ranges and
matrices are marked as supported.
Because grayscale formats are currently handled very inconsistently (and
in particular, assumed as forced full-range by swscale), we exclude them
from negotiation altogether for the time being, to get this API merged.
After filter negotiation is available, we can relax the
grayscale-is-forced-jpeg restriction again, when it will be more
feasible to do so without breaking a million test cases.
Note that this commit updates one FATE test as a consequence of the
sanity fallback for non-YUV formats. In particular, the test case now
writes rgb24(pc, gbr/unspecified/unspecified) to the matroska file,
instead of rgb24(unspecified/unspecified/unspecified) as before.
Some encoders (e.g., libx264) dump encoder configuration as user
data unregistered SEI message. This option try to print it as
ascii character when possible.
Signed-off-by: Zhao Zhili <zhilizhao@tencent.com>
This can be used to run tests multple times, with e.g. differing
QEMU settings, by adding something like this to the FATE configuration
file:
target_exec="qemu-aarch64-static"
fate_targets="fate-checkasm fate-cpu"
fate_environments="sve128 sve256 sve512"
sve128_env="QEMU_CPU=max,sve128=on"
sve256_env="QEMU_CPU=max,sve256=on"
sve512_env="QEMU_CPU=max,sve512=on"
It's also possible to customize the target_exec command further
by injecting a sufficiently quoted variable into it, which then can
be updated for each run, e.g. target_exec="\$(CUR_EXEC_CMD)".
For each of the environment names in fate_environments, the tests
that are run get the name suffixed on the fate tests in the
test log and fate report, e.g. "fate-checkasm-h264dsp_sve128".
Signed-off-by: Martin Storsjö <martin@martin.st>
This can be useful if doing testing of uncommon CPU extensions by
running tests with QEMU (by configuring with e.g.
"target_exec=qemu-aarch64"), by only running the checkasm tests,
to get a reasonable test coverage without excessive test runtime.
For such a config, setting fate_targets="fate-checkasm fate-cpu"
can be a good tradeoff.
Signed-off-by: Martin Storsjö <martin@martin.st>
