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).
tests/checkasm/checkasm:
C LSX LASX
hevc_idct_32x32_8_c: 1243.0 211.7 101.7
Speedup of decoding H265 4K 30FPS 30Mbps on
3A6000 with 8 threads is 1fps(56fps-->57fps).
Reviewed-by: yinshiyou-hf@loongson.cn
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
After this patch, the peformance of decoding H265 4K 30FPS 30Mbps
on 3A6000 with 8 threads improves 2fps (45fps-->47fsp).
Reviewed-by: yinshiyou-hf@loongson.cn
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixed blackstripe on bottom or segmentation fault in case
when patch width and height differ.
Signed-off-by: Vladimir Petrov <vppetrovmms@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
The device can be selected by GPU name or index. For example,
ffplay -hwaccel cuda \
-vulkan_params device="NVIDIA GeForce RTX 3060" \
foo.mp4
ffplay -hwaccel cuda -vulkan_params device="0" foo.mp4
Please note that select device by index only supported by hwcontext,
not by libplacebo.
Signed-off-by: Zhao Zhili <zhilizhao@tencent.com>
This second patch fixes the following error at the end of a .STR stream conversion:
[in#0/psxstr @ 0000000000681e80] Error during demuxing: I/O error
It's been a bit of trial and error as I've never used ffmpeg, but returning AVERROR_EOF appears to be the way to go (doesn't complain anymore).
Signed-off-by: aybe <aybe@users.noreply.github.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This third patch fixes warnings that are false positives (still on STRv1).
That's because these sectors are simply empty ones as can be read in "System Description CD-ROM XA, May 1991,
4.3.2.3".
Haven't attempted significant refactoring as it just works, left a comment instead about the situation.
The result is that there are no more false warnings when converting.
Signed-off-by: aybe <aybe@users.noreply.github.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This replaces the riscv specific handling from
7212466e73 (which essentially is
reverted), with a different implementation of the same (plus a bit
more), based on the corresponding feature in dav1d's checkasm,
supporting both Unix and Windows.
See in particular the dav1d commits
0b6ee30eab2400e4f85b735ad29a68a842c34e21,
0421f787ea592fd2cc74c887f20b8dc31393788b,
8501a4b20135f93a4c3b426468e2240e872949c5 and
d23e87f7aee26ddcf5f7a2e185112031477599a7, authored by Henrik Gramner.
The overall approach compared to the existing implementation for
riscv is the same; set up a signal handler, store the state with
sigsetjmp, jump out of the crashing function with siglongjmp.
The main difference is in what happens when the signal handler
is invoked. In the previous implementation, it would resume from
right before calling the crashing function, and then skip that call
based on the setjmp return value.
In the imported implementation from dav1d, we return to right before
the check_func() call, which will skip testing the current function
(as the pointer is the same as it was before).
Other differences are:
- Support for other signal handling mechanisms (Windows
AddVectoredExceptionHandler)
- Using RtlCaptureContext/RtlRestoreContext instead of setjmp/longjmp
on Windows with SEH
- Only catching signals once per function - if more than one
signal is delivered before signal handling is reenabled, any
signal is handled as it would without our handler
- Not using an arch specific signal handler written in assembly
Signed-off-by: Martin Storsjö <martin@martin.st>
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.
Adding my new gpg key that I will be using from now on.
This key is ed25519, which is more secure than the old rsa4096.
Signed-off-by: Leo Izen <leo.izen@gmail.com>
The layout for the frame flags is as follow:
chroma_format u(2)
reserved u(2)
interlace_mode u(2)
reserved u(2)
chroma_format has 2 allowed values:
0: reserved
1: reserved
2: 4:2:2
3: 4:4:4
interlace_mode has 3 allowed values:
0: progressive
1: tff
2: bff
3: reserved
0x80 is what we expect for "422 not interlaced", and the extra 0x2 from
0x82 is actually writing into the reserved bits.
This byte represents 4 reserved bits followed by 4 alpha_channel_type bits.
alpha_channel_type currently has 3 differents defined values: 0 (no
alpha), 1 (8b alpha), and 2 (16b alpha), all the other values are
reserved. The 4 initial reserved bits are expected to be 0.
This byte represents 4 reserved bits followed by 4 alpha_channel_type bits.
alpha_channel_type currently has 3 differents defined values: 0 (no
alpha), 1 (8b alpha), and 2 (16b alpha), all the other values are
reserved. This part is correctly written (alpha_bits>>3 does the correct
thing), but the 4 initial bits are reserved.
Quoting SMPTE RDD 36:2015:
A decoder shall abort if it encounters a bitstream with an unsupported
bitstream_version value. If 0, the value of the chroma_format syntax
element shall be 2 (4:2:2 sampling) and the value of the
alpha_channel_type element shall be 0 (no encoded alpha); if 1, any
permissible value may be used for those syntax elements.
So if we're not in 4:2:2 or if there is alpha, we are not allowed to use
version 0.
Quoting SMPTE RDD 36:2015:
A decoder shall abort if it encounters a bitstream with an unsupported
bitstream_version value. If 0, the value of the chroma_format syntax
element shall be 2 (4:2:2 sampling) and the value of the
alpha_channel_type element shall be 0 (no encoded alpha); if 1, any
permissible value may be used for those syntax elements.
So if we're not in 4:2:2 or if there is alpha, we are not allowed to use
version 0.