Fix audio processing for streams with missing audio_bitrate

CHANGELOG.md

@@ -63,6 +63,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Fixed mono clips crashing when `audio_fadeout` FX applied [\#1578](https://github.com/Zulko/moviepy/pull/1578)
 - Fixed scroll FX not being scrolling [\#1591](https://github.com/Zulko/moviepy/pull/1591)
 - Fixed parsing FFMPEG streams with square brackets [\#1781](https://github.com/Zulko/moviepy/pull/1781)
+- Fixed audio processing for streams with missing `audio_bitrate` [\#1783](https://github.com/Zulko/moviepy/pull/1783)
 
 
 ## [v2.0.0.dev2](https://github.com/zulko/moviepy/tree/v2.0.0.dev2) (2020-10-05)

moviepy/video/io/ffmpeg_reader.py

@@ -585,6 +585,9 @@ def parse(self):
                 if self.result.get("audio_bitrate"):
                     break
 
+            if "audio_bitrate" not in self.result:
+                self.result["audio_bitrate"] = None
+
         result = self.result
 
         # reset state of the parser

tests/test_ffmpeg_reader.py

@@ -527,6 +527,22 @@ def test_stream_square_brackets():
     assert d["inputs"][0]["streams"][1]["language"] is None
 
 
+def test_stream_missing_audio_bitrate():
+    infos = """
+Input #0, mpeg, from 'clip.mp4':
+  Duration: 00:02:15.00, start: 52874.498178, bitrate: 266 kb/s
+    Stream #0:0[0x1e0]: Video: ..., 25 tbr, 90k tbn, 50 tbc
+    Stream #0:1[0x1c0]: Audio: mp2, 0 channels, s16p
+At least one output file must be specified"""
+
+    d = FFmpegInfosParser(infos, "clip.mp4").parse()
+
+    assert d
+    assert len(d["inputs"][0]["streams"]) == 2
+    assert d["audio_found"]
+    assert d["audio_bitrate"] is None
+
+
 def test_sequential_frame_pos():
     """test_video.mp4 contains 5 frames at 1 fps.
     Each frame is 1x1 pixels and the sequence is Red, Green, Blue, Black, White.