Move iter_motion to analyze.py

auto_editor/analyze.py

@@ -6,13 +6,16 @@
 from fractions import Fraction
 from typing import TYPE_CHECKING
 
+import av
 import numpy as np
+from av.subtitles.subtitle import AssSubtitle
 
 from auto_editor import version
 from auto_editor.utils.subtitle_tools import convert_ass_to_text
 from auto_editor.wavfile import read
 
 if TYPE_CHECKING:
+    from collections.abc import Iterator
     from fractions import Fraction
     from typing import Any
 
@@ -86,6 +89,53 @@ def obj_tag(tag: str, tb: Fraction, obj: dict[str, Any]) -> str:
     return key
 
 
+def iter_motion(src, tb, stream: int, blur: int, width: int) -> Iterator[float]:
+    container = av.open(src.path, "r")
+
+    video = container.streams.video[stream]
+    video.thread_type = "AUTO"
+
+    prev_frame = None
+    current_frame = None
+    total_pixels = src.videos[0].width * src.videos[0].height
+    index = 0
+    prev_index = -1
+
+    graph = av.filter.Graph()
+    graph.link_nodes(
+        graph.add_buffer(template=video),
+        graph.add("scale", f"{width}:-1"),
+        graph.add("format", "gray"),
+        graph.add("gblur", f"sigma={blur}"),
+        graph.add("buffersink"),
+    ).configure()
+
+    for unframe in container.decode(video):
+        if unframe.pts is None:
+            continue
+
+        graph.push(unframe)
+        frame = graph.pull()
+        assert frame.time is not None
+        index = round(frame.time * tb)
+
+        current_frame = frame.to_ndarray()
+        if prev_frame is None:
+            value = 0.0
+        else:
+            # Use `int16` to avoid underflow with `uint8` datatype
+            diff = np.abs(prev_frame.astype(np.int16) - current_frame.astype(np.int16))
+            value = np.count_nonzero(diff) / total_pixels
+
+        for _ in range(index - prev_index):
+            yield value
+
+        prev_frame = current_frame
+        prev_index = index
+
+    container.close()
+
+
 @dataclass(slots=True)
 class Levels:
     ensure: Ensure
@@ -114,8 +164,6 @@ def media_length(self) -> int:
             return ticks
 
         # If there's no audio, get length in video metadata.
-        import av
-
         with av.open(f"{self.src.path}") as cn:
             if len(cn.streams.video) < 1:
                 self.log.error("Could not get media duration")
@@ -232,9 +280,6 @@ def subtitle(
         except re.error as e:
             self.log.error(e)
 
-        import av
-        from av.subtitles.subtitle import AssSubtitle
-
         try:
             container = av.open(self.src.path, "r")
             subtitle_stream = container.streams.subtitles[stream]
@@ -293,66 +338,35 @@ def subtitle(
         return result
 
     def motion(self, stream: int, blur: int, width: int) -> NDArray[np.float64]:
-        import av
-
         if stream >= len(self.src.videos):
             raise LevelError(f"motion: video stream '{stream}' does not exist.")
 
         mobj = {"stream": stream, "width": width, "blur": blur}
         if (arr := self.read_cache("motion", mobj)) is not None:
             return arr
 
-        container = av.open(f"{self.src.path}", "r")
-
-        video = container.streams.video[stream]
-        video.thread_type = "AUTO"
+        with av.open(self.src.path, "r") as container:
+            video = container.streams.video[stream]
+            inaccurate_dur = (
+                1024
+                if video.duration is None or video.time_base is None
+                else int(video.duration * video.time_base * self.tb)
+            )
 
-        inaccurate_dur = 1 if video.duration is None else video.duration
-        self.bar.start(inaccurate_dur, "Analyzing motion")
+        bar = self.bar
+        bar.start(inaccurate_dur, "Analyzing motion")
 
-        prev_frame = None
-        current_frame = None
-        total_pixels = self.src.videos[0].width * self.src.videos[0].height
+        threshold_list = np.zeros((inaccurate_dur), dtype=np.float64)
         index = 0
 
-        graph = av.filter.Graph()
-        graph.link_nodes(
-            graph.add_buffer(template=video),
-            graph.add("scale", f"{width}:-1"),
-            graph.add("format", "gray"),
-            graph.add("gblur", f"sigma={blur}"),
-            graph.add("buffersink"),
-        ).configure()
-
-        threshold_list = np.zeros((1024), dtype=np.float64)
-
-        for unframe in container.decode(video):
-            graph.push(unframe)
-            frame = graph.pull()
-
-            # Showing progress ...
-            assert frame.time is not None
-            index = int(frame.time * self.tb)
-            if frame.pts is not None:
-                self.bar.tick(frame.pts)
-
-            current_frame = frame.to_ndarray()
-
+        for value in iter_motion(self.src, self.tb, stream, blur, width):
             if index > len(threshold_list) - 1:
                 threshold_list = np.concatenate(
-                    (threshold_list, np.zeros((len(threshold_list)), dtype=np.float64)),
-                    axis=0,
-                )
-
-            if prev_frame is not None:
-                # Use `int16` to avoid underflow with `uint8` datatype
-                diff = np.abs(
-                    prev_frame.astype(np.int16) - current_frame.astype(np.int16)
+                    (threshold_list, np.zeros((len(threshold_list)), dtype=np.float64))
                 )
-                threshold_list[index] = np.count_nonzero(diff) / total_pixels
+            threshold_list[index] = value
+            bar.tick(index)
+            index += 1
 
-            prev_frame = current_frame
-
-        self.bar.end()
-        container.close()
+        bar.end()
         return self.cache("motion", mobj, threshold_list[:index])

auto_editor/subcommands/levels.py

@@ -10,7 +10,7 @@
 import numpy as np
 from av.audio.fifo import AudioFifo
 
-from auto_editor.analyze import LevelError, Levels
+from auto_editor.analyze import LevelError, Levels, iter_motion
 from auto_editor.ffwrapper import FFmpeg, initFileInfo
 from auto_editor.lang.palet import env
 from auto_editor.lib.contracts import is_bool, is_nat, is_nat1, is_str, is_void, orc
@@ -130,53 +130,6 @@ def iter_audio(src, tb: Fraction, stream: int = 0) -> Iterator[float]:
         container.close()
 
 
-def iter_motion(src, tb, stream: int, blur: int, width: int) -> Iterator[float]:
-    container = av.open(src.path, "r")
-
-    video = container.streams.video[stream]
-    video.thread_type = "AUTO"
-
-    prev_frame = None
-    current_frame = None
-    total_pixels = src.videos[0].width * src.videos[0].height
-    index = 0
-    prev_index = 0
-
-    graph = av.filter.Graph()
-    graph.link_nodes(
-        graph.add_buffer(template=video),
-        graph.add("scale", f"{width}:-1"),
-        graph.add("format", "gray"),
-        graph.add("gblur", f"sigma={blur}"),
-        graph.add("buffersink"),
-    ).configure()
-
-    for unframe in container.decode(video):
-        if unframe.pts is None:
-            continue
-
-        graph.push(unframe)
-        frame = graph.pull()
-        assert frame.time is not None
-        index = round(frame.time * tb)
-
-        current_frame = frame.to_ndarray()
-        if prev_frame is None:
-            value = 0.0
-        else:
-            # Use `int16` to avoid underflow with `uint8` datatype
-            diff = np.abs(prev_frame.astype(np.int16) - current_frame.astype(np.int16))
-            value = np.count_nonzero(diff) / total_pixels
-
-        for _ in range(index - prev_index):
-            yield value
-
-        prev_frame = current_frame
-        prev_index = index
-
-    container.close()
-
-
 def main(sys_args: list[str] = sys.argv[1:]) -> None:
     parser = levels_options(ArgumentParser("levels"))
     args = parser.parse_args(LevelArgs, sys_args)
@@ -232,7 +185,6 @@ def main(sys_args: list[str] = sys.argv[1:]) -> None:
         levels = Levels(ensure, src, tb, bar, temp, log)
         try:
             if method == "audio":
-                # print_arr(levels.audio(**obj))
                 print_arr_gen(iter_audio(src, tb, **obj))
             elif method == "motion":
                 print_arr_gen(iter_motion(src, tb, **obj))