libavcodec currently exports four avpriv symbols that deal with
PixelFormatTags: avpriv_get_raw_pix_fmt_tags, avpriv_find_pix_fmt,
avpriv_pix_fmt_bps_avi and avpriv_pix_fmt_bps_mov. The latter two are
lists of PixelFormatTags, the former returns such a list and the second
searches a list for a pixel format that matches a given fourcc; only
one of the aforementioned three lists is ever searched.
Yet for avpriv_pix_fmt_bps_avi, avpriv_pix_fmt_bps_mov and
avpriv_find_pix_fmt the overhead of exporting these functions actually
exceeds the size of said objects (at least for ELF; the following numbers
are for x64 Ubuntu 20.10):
The code size of avpriv_find_pix_fmt is small (GCC 10.2 37B, Clang 11 41B),
yet exporting it adds a 20B string for the name alone to the exporting
as well as to each importing library; there is more: Four bytes in the
exporting libraries .gnu.hash; two bytes each for the exporting as well
as each importing libraries .gnu.version; 24B in the exporting as well
as each importing libraries .dynsym; 16B+24B for an entry in .plt as
well as the accompanying relocation entry in .rela.plt for each
importing library.
The overhead for the lists is similar: The strings are 23B and the
.plt+.rela.plt pair is replaced by 8B+24B for an entry in .got and
a relocation entry in .rela.dyn. These lists have a size of 80 resp.
72 bytes.
Yet for ff_raw_pix_fmt_tags, exporting it is advantageous compared to
duplicating it into libavformat and potentially libavdevice. Therefore
this commit replaces all library uses of the four symbols with a single
function that is exported for shared builds. It has an enum parameter
to choose the desired list besides the parameter for the fourcc. New
lists can be supported with new enum values.
Unfortunately, avpriv_get_raw_pix_fmt_tags could not be removed, as the
fourcc2pixfmt tool uses the table of raw pix fmts. No other user of this
function remains.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Fixes regression in a1c4929f: there apparently are devices out there
that expose a pin default format that has parameters outside the
capabilities of any of the formats exposed on the pin (sic?). The
VirtualCam plugin (v 2.0.5) of OBS-Studio (v 27.1.3) is such a device.
Now when a default format was found, but not selected when iterating all
formats, fall back to directly setting the default format.
Signed-off-by: Diederick Niehorster <dcnieho@gmail.com>
Reviewed-by: Roger Pack <rogerdpack2@gmail.com>
Some DirectShow devices (Logitech C920 webcam) expose each DirectShow
format they support twice, once without and once with extended color
information. During format selection, both match, this patch ensures
that the format with extended color information is selected if it is
available, else it falls back to a matching format without such
information. This also necessitated a new code path taken for default
formats of a device (when user didn't request any specific video size,
etc), because the default format may be one without extended color
information when a twin with extended color information is also
available. Getting the extended color information when available is
important as it allows setting the color space, range, primaries,
transfer characteristics and chroma location of the stream provided by
dshow, enabling users to get more correct color automatically out of
their device.
Closes: #9271
Signed-off-by: Diederick Niehorster <dcnieho@gmail.com>
Reviewed-by: Roger Pack <rogerdpack2@gmail.com>
Enabled discovering a DirectShow device's color range, space, primaries,
transfer characteristics and chroma location, if the device exposes that
information. Sets them in the stream's codecpars.
Co-authored-by: Valerii Zapodovnikov <val.zapod.vz@gmail.com>
Signed-off-by: Diederick Niehorster <dcnieho@gmail.com>
Reviewed-by: Roger Pack <rogerdpack2@gmail.com>
The list returned by get_device_list now contains info about what media
type(s), if any, can be provided by each device.
Signed-off-by: Diederick Niehorster <dcnieho@gmail.com>
Reviewed-by: Roger Pack <rogerdpack2@gmail.com>
the list_devices option of dshow didn't indicate whether a specific
device provides audio or video output. This patch iterates through all
media formats of all pins exposed by the device to see what types it
provides for capture, and prints this to the console for each device.
Importantly, this now allows to find devices that provide both audio and
video, and devices that provide neither.
Signed-off-by: Diederick Niehorster <dcnieho@gmail.com>
Reviewed-by: Roger Pack <rogerdpack2@gmail.com>
avdevice/dshow is a realtime device and as such does not support
seeking. Therefore, its demuxer format should define the
AVFMT_NOBINSEARCH, AVFMT_NOGENSEARCH and AVFMT_NO_BYTE_SEEK flags.
With these flags set, attempting to seek (with, e.g.,
avformat_seek_file()) correctly yields -1 (operation not permitted)
instead of -22 (invalid argument).
This actually seems to apply to many other devices, at least the
gdigrab, v4l2, vfwcap, x11grab, fbdev, kmsgrab and android_camera
devices, from reading the source.
Signed-off-by: Diederick Niehorster <dcnieho@gmail.com>
Reviewed-by: Roger Pack <rogerdpack2@gmail.com>
The dshow avdevice ignores timestamps for video frames provided by the
DirectShow device, instead using wallclock time, apparently because the
implementer of this code had a device that provided unreliable
timestamps. Me (and others) would like to use the device's timestamps.
The new use_video_device_timestamps option for dshow device enables them
to do so. Since the majority of video devices out there probably provide
fine timestamps, this patch sets the default to using the device
timestamps, which means best fidelity timestamps are used by default.
Using the new option, the user can switch this off and revert to the old
behavior, so a fall back remains available in case the device provides
broken timestamps.
add use_video_device_timestamps to docs.
Closes: #8620
Signed-off-by: Diederick Niehorster <dcnieho@gmail.com>
Reviewed-by: Roger Pack <rogerdpack2@gmail.com>
list_options true would crash when both a video and an audio device were
specified as input. Crash would occur on line 784 because
ctx->device_unique_name[otherDevType] would be NULL
Signed-off-by: Diederick Niehorster <dcnieho@gmail.com>
Reviewed-by: Roger Pack <rogerdpack2@gmail.com>
This is possible now that the next-API is gone.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Signed-off-by: James Almer <jamrial@gmail.com>
The next pointer is kept at the end for backwards compatability until the
major bump, when it should ideally be moved at the front.
Signed-off-by: James Almer <jamrial@gmail.com>
Current if statement would always be false due to assigning the value of
S_OK which equals 0.
Signed-off-by: FearThe1337 <git@fearthe1337.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
actually have both video and audio output pins, so make the audio pins
accessible by video source name.
Signed-off-by: rogerdpack <rogerpack2005@gmail.com>
dshow_capture.h sets up various flags before including windows headers
this must occur before other headers (like os_support.h) include these
headers without the setup
This could be fixed differently but for now this fixes building on mingw
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Used to expose ff_raw_pix_fmt_tags[] to other libav* libraries
Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
