Fix video conversion bug (#4467)

* Fix bug

* CHANGELOG

* Add feature

* Revert "Add feature"

This reverts commit 834fed6a9f48c4c6fc2d73ff2f8e080302a82def.

---------

Co-authored-by: aliabid94 <aabid94@gmail.com>

CHANGELOG.md

@@ -12,6 +12,7 @@
 - Ensure Tabs only occupy the space required by [@pngwn](https://github.com/pngwn) in [PR 4419](https://github.com/gradio-app/gradio/pull/4419)
 - Ensure components have the correct empty sizes to prevent empty containers from collapsing by [@pngwn](https://github.com/pngwn) in [PR 4447](https://github.com/gradio-app/gradio/pull/4447).
 - Frontend code no longer crashes when there is a relative URL in an `<a>` element, by [@akx](https://github.com/akx) in [PR 4449](https://github.com/gradio-app/gradio/pull/4449).
+- Fix bug where setting `format='mp4'` on a video component would cause the function to error out if the uploaded video was not playable by [@freddyaboulton](https://github.com/freddyaboulton) in [PR 4467](https://github.com/gradio-app/gradio/pull/4467)
 
 ## Other Changes:
 

gradio/components.py

@@ -2413,9 +2413,7 @@ class Video(
         """
         if video is None:
             return None
-
         returned_format = video.split(".")[-1].lower()
-
         if self.format is None or returned_format == self.format:
             conversion_needed = False
         else:
@@ -2436,9 +2434,16 @@ class Video(
                 "Video does not have browser-compatible container or codec. Converting to mp4"
             )
             video = processing_utils.convert_video_to_playable_mp4(video)
+        # Recalculate the format in case convert_video_to_playable_mp4 already made it the
+        # selected format
+        returned_format = video.split(".")[-1].lower()
         if self.format is not None and returned_format != self.format:
             output_file_name = video[0 : video.rindex(".") + 1] + self.format
-            ff = FFmpeg(inputs={video: None}, outputs={output_file_name: None})
+            ff = FFmpeg(
+                inputs={video: None},
+                outputs={output_file_name: None},
+                global_options="-y",
+            )
             ff.run()
             video = output_file_name
 

test/test_components.py

@@ -1409,6 +1409,15 @@ class TestVideo:
             full_path_to_output = Path(tmp_not_playable_vid.name).with_suffix(".mp4")
             assert processing_utils.video_is_playable(str(full_path_to_output))
 
+    def test_convert_video_to_playable_format(self, monkeypatch, tmp_path):
+        test_file_dir = Path(Path(__file__).parent, "test_files")
+        monkeypatch.setenv("GRADIO_TEMP_DIR", str(tmp_path))
+        video = gr.Video(format="mp4")
+        output = video.postprocess(
+            str(test_file_dir / "playable_but_bad_container.mkv")
+        )
+        assert Path(output[0]["name"]).suffix == ".mp4"
+
     @patch("pathlib.Path.exists", MagicMock(return_value=False))
     @patch("gradio.components.FFmpeg")
     def test_video_preprocessing_flips_video_for_webcam(self, mock_ffmpeg):