Start with the problem in front of you.

Compare the saved artifact with the preview before diagnosing a black image. A black preview and genuinely invalid output pixels are different observations.

This occurs when a GPU operation lacks a compatible compiled kernel. A device may be too new, omitted as an older architecture, or unsupported by a particular extension. It is not the same as running out of VRAM.

A codec rejecting nonfinite samples is not necessarily missing. Follow the audio entering it back through processing and decoding.

Determine whether the missing item is FFmpeg itself, an input file or an encoder. The appearance of ffmpeg in a log does not justify reinstalling the whole video stack.

Use the official basic image-to-image path to understand how input pixels influence a result. Denoise and seed serve different purposes; there is no single best value for every image.

A painted mask is only part of an inpainting workflow. Check the image, mask interpretation and supported model/encoding path together.

A larger image can mean new content beyond the frame or more pixels representing the existing composition. Choosing the wrong workflow may produce the requested dimensions but the wrong content.

Check PyAV, its linked libraries and an external FFmpeg executable as separate dependencies.

Use the dedicated background-removal template and check target sizing, alpha retention and unintended changes to the subject.

Request transparency, retain the original PNG and verify its alpha values rather than trusting a viewer background.

This case-led guide concerns a reported fp16-intermediate scenario, not every silent track. First establish whether audio exists and is valid before composition.

Existing output can still be unplayable, silent or the wrong length. Establish whether the issue belongs to generation, encoding, saving or the target player.

VHS_VideoCombine illustrates the media layer around generated content. Reading, sampling frames, combining and saving should not be confused with the generation model itself.