fix: keep video movflags scoped to container

[ahfoysal]

Fixes #14755.

VideoFromComponents.save_to() was passing movflags=use_metadata_tags through PyAV's global options argument. PyAV applies options to the container and streams, so the AAC encoder can see movflags while opening the audio stream and reject it.

This switches the shared write kwargs helper to container_options, then has VideoFromComponents.save_to() use that same helper instead of keeping its own av.open() kwargs. That keeps metadata tags on the MP4 container without leaking the flag into stream codec options.

Tests:

• uv run --with-requirements requirements.txt --with-requirements tests-unit/requirements.txt pytest tests-unit/comfy_api_test/video_types_test.py -q
• uv run --with ruff ruff check comfy_api/latest/_input_impl/video_types.py tests-unit/comfy_api_test/video_types_test.py
• python3 -m py_compile comfy_api/latest/_input_impl/video_types.py tests-unit/comfy_api_test/video_types_test.py
• git diff --check

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• comfy_api/latest/_input_impl/video_types.py
• tests-unit/comfy_api_test/video_types_test.py

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Files:

• tests-unit/comfy_api_test/video_types_test.py
• comfy_api/latest/_input_impl/video_types.py

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Files:

• tests-unit/comfy_api_test/video_types_test.py
• comfy_api/latest/_input_impl/video_types.py

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Files:

• tests-unit/comfy_api_test/video_types_test.py
• comfy_api/latest/_input_impl/video_types.py

🧠 Learnings (1)

📚 Learning: 2026-02-21T14:01:41.482Z

Learnt from: pythongosssss
Repo: Comfy-Org/ComfyUI PR: 12555
File: comfy_extras/nodes_glsl.py:719-724
Timestamp: 2026-02-21T14:01:41.482Z
Learning: In PyOpenGL, bare Python scalars can be accepted for 1-element array parameters by NumberHandler. This means you can pass an int/float directly to OpenGL texture deletion (e.g., glDeleteTextures(tex)) without wrapping in a list. Verify function-specific expectations and ensure types match what the OpenGL call expects; use explicit lists only when the API requires an array.

Applied to files:

• tests-unit/comfy_api_test/video_types_test.py
• comfy_api/latest/_input_impl/video_types.py

🔇 Additional comments (2)

comfy_api/latest/_input_impl/video_types.py (1)

33-52: LGTM!

Also applies to: 511-529

tests-unit/comfy_api_test/video_types_test.py (1)

8-9: LGTM!

Also applies to: 242-262

---

📝 Walkthrough

Walkthrough

Changes

This change modifies how PyAV container write options are configured when saving video output. The movflags setting for MP4 metadata tag preservation is moved from the options dictionary to container_options within the kwargs returned by get_open_write_kwargs. The save_to method for MP4 output now delegates to get_open_write_kwargs rather than manually constructing av.open parameters. Corresponding unit tests were added to verify the new kwargs structure, including format handling for BytesIO targets and explicit container requests.

Sequence Diagram(s)

See hidden artifact diagram above.

Related Issues: Not specified in provided context.

Related PRs: Not specified in provided context.

Suggested labels: bug, video, tests

Suggested reviewers: Not specified in provided context.

Poem
A rabbit tweaks a movie flag,
From "options" to a container bag,
Metadata tags now safely stay,
Tests confirm it, hip hip hooray!
🐇🎬

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly reflects the main change: scoping movflags to the video container.
Description check	✅ Passed	The description accurately explains the bug and the container_options fix in this PR.
Linked Issues check	✅ Passed	The code changes address #14755 by keeping movflags container-scoped and updating save_to accordingly.
Out of Scope Changes check	✅ Passed	The changes stay focused on the movflags fix and matching tests, with no unrelated additions.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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