From cb9f13ea08bc004bd600c3cce8b1a394d407a1e8 Mon Sep 17 00:00:00 2001
From: Christian Byrne <cbyrne@comfy.org>
Date: Sun, 4 May 2025 14:45:41 -0700
Subject: [PATCH] Use upstream PR: Support saving Comfy VIDEO type to buffer
 (#123)

---
 comfy_api/input_impl/video_types.py | 56 +++++++++++++++++++++--------
 1 file changed, 41 insertions(+), 15 deletions(-)

diff --git a/comfy_api/input_impl/video_types.py b/comfy_api/input_impl/video_types.py
index 146d6daf8..d0b0b36d2 100644
--- a/comfy_api/input_impl/video_types.py
+++ b/comfy_api/input_impl/video_types.py
@@ -12,6 +12,46 @@ import torch
 from comfy_api.input import VideoInput
 from comfy_api.util import VideoContainer, VideoCodec, VideoComponents
 
+
+def container_to_output_format(container_format: str | None) -> str | None:
+    """
+    A container's `format` may be a comma-separated list of formats.
+    E.g., iso container's `format` may be `mov,mp4,m4a,3gp,3g2,mj2`.
+    However, writing to a file/stream with `av.open` requires a single format,
+    or `None` to auto-detect.
+    """
+    if not container_format:
+        return None  # Auto-detect
+
+    if "," not in container_format:
+        return container_format
+
+    formats = container_format.split(",")
+    return formats[0]
+
+
+def get_open_write_kwargs(
+    dest: str | io.BytesIO, container_format: str, to_format: str | None
+) -> dict:
+    """Get kwargs for writing a `VideoFromFile` to a file/stream with `av.open`"""
+    open_kwargs = {
+        "mode": "w",
+        # If isobmff, preserve custom metadata tags (workflow, prompt, extra_pnginfo)
+        "options": {"movflags": "use_metadata_tags"},
+    }
+
+    is_write_to_buffer = isinstance(dest, io.BytesIO)
+    if is_write_to_buffer:
+        # Set output format explicitly, since it cannot be inferred from file extension
+        if to_format == VideoContainer.AUTO:
+            to_format = container_format.lower()
+        elif isinstance(to_format, str):
+            to_format = to_format.lower()
+        open_kwargs["format"] = container_to_output_format(to_format)
+
+    return open_kwargs
+
+
 class VideoFromFile(VideoInput):
     """
     Class representing video input from a file.
@@ -116,22 +156,8 @@ class VideoFromFile(VideoInput):
                 )
 
             streams = container.streams
-            open_kwargs = {
-                "mode": "w",
-                "options": {"movflags": "use_metadata_tags"}
-            }
-
-            if not isinstance(path, str):
-                # Explicit format is needed for non-path destinations (like BytesIO)
-                output_format_str = (
-                    format.value.lower()
-                    if format != VideoContainer.AUTO
-                    else container.format.name
-                )
-                if "," in output_format_str:
-                    output_format_str = output_format_str.split(",")[0]
-                open_kwargs["format"] = output_format_str
 
+            open_kwargs = get_open_write_kwargs(path, container_format, format)
             with av.open(path, **open_kwargs) as output_container:
                 # Copy over the original metadata
                 for key, value in container.metadata.items():