import cython
from cython.cimports.av.error import err_check
from cython.cimports.av.opaque import opaque_container
from cython.cimports.av.utils import avrational_to_fraction, to_avrational
from av.sidedata.sidedata import SideDataContainer
@cython.cclass
class Frame:
"""
Base class for audio and video frames.
See also :class:`~av.audio.frame.AudioFrame` and :class:`~av.video.frame.VideoFrame`.
"""
def __cinit__(self, *args, **kwargs):
with cython.nogil:
self.ptr = lib.av_frame_alloc()
def __dealloc__(self):
with cython.nogil:
lib.av_frame_free(cython.address(self.ptr))
def __repr__(self):
return f"<av.{self.__class__.__name__} pts={self.pts} at 0x{id(self):x}>"
@cython.cfunc
def _copy_internal_attributes(self, source: Frame, data_layout: cython.bint = True):
# Mimic another frame
self._time_base = source._time_base
lib.av_frame_copy_props(self.ptr, source.ptr)
if data_layout:
# TODO: Assert we don't have any data yet.
self.ptr.format = source.ptr.format
self.ptr.width = source.ptr.width
self.ptr.height = source.ptr.height
self.ptr.ch_layout = source.ptr.ch_layout
@cython.cfunc
def _init_user_attributes(self):
pass # Dummy to match the API of the others.
@cython.cfunc
def _rebase_time(self, dst: lib.AVRational):
if not dst.num:
raise ValueError("Cannot rebase to zero time.")
if not self._time_base.num:
self._time_base = dst
return
if self._time_base.num == dst.num and self._time_base.den == dst.den:
return
if self.ptr.pts != lib.AV_NOPTS_VALUE:
self.ptr.pts = lib.av_rescale_q(self.ptr.pts, self._time_base, dst)
if self.ptr.duration != 0:
self.ptr.duration = lib.av_rescale_q(
self.ptr.duration, self._time_base, dst
)
self._time_base = dst
@property
def dts(self):
"""
The decoding timestamp copied from the :class:`~av.packet.Packet` that triggered returning this frame in :attr:`time_base` units.
(if frame threading isn't used) This is also the Presentation time of this frame calculated from only :attr:`.Packet.dts` values without pts values.
:type: int | None
"""
if self.ptr.pkt_dts == lib.AV_NOPTS_VALUE:
return None
return self.ptr.pkt_dts
@dts.setter
def dts(self, value):
if value is None:
self.ptr.pkt_dts = lib.AV_NOPTS_VALUE
else:
self.ptr.pkt_dts = value
@property
def pts(self):
"""
The presentation timestamp in :attr:`time_base` units for this frame.
This is the time at which the frame should be shown to the user.
:type: int | None
"""
if self.ptr.pts == lib.AV_NOPTS_VALUE:
return None
return self.ptr.pts
@pts.setter
def pts(self, value):
if value is None:
self.ptr.pts = lib.AV_NOPTS_VALUE
else:
self.ptr.pts = value
@property
def duration(self):
"""
The duration of the frame in :attr:`time_base` units
:type: int
"""
return self.ptr.duration
@duration.setter
def duration(self, value):
self.ptr.duration = value
@property
def time(self):
"""
The presentation time in seconds for this frame.
This is the time at which the frame should be shown to the user.
:type: float | None
"""
if self.ptr.pts == lib.AV_NOPTS_VALUE:
return None
return float(self.ptr.pts) * self._time_base.num / self._time_base.den
@property
def time_base(self):
"""
The unit of time (in fractional seconds) in which timestamps are expressed.
:type: fractions.Fraction | None
"""
if self._time_base.num:
return avrational_to_fraction(cython.address(self._time_base))
@time_base.setter
def time_base(self, value):
to_avrational(value, cython.address(self._time_base))
@property
def is_corrupt(self):
"""
Is this frame corrupt?
:type: bool
"""
return self.ptr.decode_error_flags != 0 or bool(
self.ptr.flags & lib.AV_FRAME_FLAG_CORRUPT
)
@property
def key_frame(self):
"""Is this frame a key frame?
Wraps :ffmpeg:`AVFrame.key_frame`.
"""
return bool(self.ptr.flags & lib.AV_FRAME_FLAG_KEY)
@key_frame.setter
def key_frame(self, v):
# PyAV makes no guarantees this does anything.
if v:
self.ptr.flags |= lib.AV_FRAME_FLAG_KEY
else:
self.ptr.flags &= ~lib.AV_FRAME_FLAG_KEY
@property
def side_data(self):
if self._side_data is None:
self._side_data = SideDataContainer(self)
return self._side_data
def make_writable(self):
"""
Ensures that the frame data is writable. Copy the data to new buffer if it is not.
This is a wrapper around :ffmpeg:`av_frame_make_writable`.
"""
ret: cython.int = lib.av_frame_make_writable(self.ptr)
err_check(ret)
@property
def opaque(self):
if self.ptr.opaque_ref is not cython.NULL:
return opaque_container.get(
cython.cast(cython.p_char, self.ptr.opaque_ref.data)
)
@opaque.setter
def opaque(self, v):
lib.av_buffer_unref(cython.address(self.ptr.opaque_ref))
if v is not None:
self.ptr.opaque_ref = opaque_container.add(v)