feat(#74): support portable ffmpeg

stagesepx/constants.py

@@ -8,3 +8,6 @@
 # report
 BACKGROUND_COLOR = r"#fffaf4"
 UNSTABLE_FLAG = r"-1"
+
+# ext
+FFMPEG = r"ffmpeg"

stagesepx/toolbox.py

@@ -255,7 +255,19 @@ def np2b64str(frame: np.ndarray) -> str:
     return b64encode(buffer).decode()
 
 
-def fps_convert(target_fps: int, source_path: str, target_path: str) -> int:
-    command: typing.List[str] = ["ffmpeg", "-i", source_path, "-r", str(target_fps), target_path]
+def fps_convert(
+    target_fps: int, source_path: str, target_path: str, ffmpeg_exe: str = None
+) -> int:
+    # for portable ffmpeg
+    if not ffmpeg_exe:
+        ffmpeg_exe = r"ffmpeg"
+    command: typing.List[str] = [
+        ffmpeg_exe,
+        "-i",
+        source_path,
+        "-r",
+        str(target_fps),
+        target_path,
+    ]
     logger.debug(f"convert video: {command}")
     return subprocess.check_call(command)

stagesepx/video.py

@@ -6,6 +6,7 @@
 import tempfile
 
 from stagesepx import toolbox
+from stagesepx import constants
 
 
 class VideoFrame(object):
@@ -79,7 +80,7 @@ def __init__(
         if fps:
             video_path = os.path.join(tempfile.mkdtemp(), f"tmp_{fps}.mp4")
             logger.debug(f"convert video, and bind path to {video_path}")
-            toolbox.fps_convert(fps, self.path, video_path)
+            toolbox.fps_convert(fps, self.path, video_path, constants.FFMPEG)
             self.path = video_path
 
         with toolbox.video_capture(path) as cap:

test/test_toolbox.py

@@ -71,5 +71,7 @@ def test_compress():
 
 def test_convert_video():
     target_fps: int = 30
-    ret = toolbox.fps_convert(target_fps, VIDEO_PATH, os.path.join(PROJECT_PATH, f"{target_fps}.mp4"))
+    ret = toolbox.fps_convert(
+        target_fps, VIDEO_PATH, os.path.join(PROJECT_PATH, f"{target_fps}.mp4")
+    )
     assert not ret

test/test_video.py

@@ -35,3 +35,13 @@ def test_convert_first():
     v = VideoObject(VIDEO_PATH, fps=30)
     v.load_frames()
     assert len(v.data) == 36
+
+
+def test_custom_ffmpeg():
+    from stagesepx import constants
+
+    constants.FFMPEG = "unknown"
+    try:
+        VideoObject(VIDEO_PATH, fps=30)
+    except FileNotFoundError:
+        pass