cleanup

pyav/decoder.py

@@ -0,0 +1,58 @@
+# People's Video Editor: high quality, GPU accelerated mp4 editor
+# Copyright (C) 2025 Roz K <roz@rozk.net>
+#
+# This file is part of People's Video Editor.
+#
+# People's Video Editor is free software: you can redistribute it and/or modify it under the terms of the
+# GNU General Public License as published by the Free Software Foundation, either version 3 of the License,
+# or (at your option) any later version.
+#
+# People's Video Editor is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+# without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+# See the GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along with People's Video Editor.
+# If not, see <https://www.gnu.org/licenses/>.
+
+from . import libav
+from .packet import Packet
+from .frame import Frame
+
+class Decoder:
+    __slots__ = '_context'
+
+    def __init__(self, stream):
+        self._context = libav.codec_alloc_context(stream.codec)
+        if not self._context:
+            raise MemoryError
+        errcode = libav.codec_parameters_to_context(self._context, stream.parameters)
+        if errcode < 0:
+            libav.codec_free_context(self._context)
+            raise Exception("Failed to set context parameters")
+        errcode = libav.codec_open(self._context, stream.codec)
+        if errcode < 0:
+            libav.codec_free_context(self._context)
+            raise Exception("Failed to open codec context")
+
+    def __del__(self):
+        if self._context:
+            libav.codec_free_context(self._context)
+
+    def decode(self, packet):
+        if not self._context:
+            return None
+        errcode = libav.codec_send_packet(self._context, packet)
+        if errcode < 0:
+            errstring = libav.strerror(errcode)
+            raise Exception(f"Failed to send packet: {errstring}")
+        frames = []
+        while True:
+            frame = Frame()
+            errcode = libav.codec_receive_frame(self._context, frame)
+            if errcode in (libav.AVERROR_EOF, libav.AVERROR_EAGAIN):
+                break
+            elif errcode < 0:
+                errstring = libav.strerror(errcode)
+                raise Exception(f"Failed to receive frame: {errstring}")
+            frames.append(frame)
+        return frames