Sources such as PNG sequences have no stereoscopic metadata, so there
was no CLI way to write container layout tags without an external
post-processor. Inject AV_PKT_DATA_STEREO3D onto the output stream
after bitstream filters and before write_header.
A bare -stereo3d applies to video and is ignored on other types; an
explicit specifier on a non-video stream is rejected.
Fixes: #24269
Reported-by: optozorax
Signed-off-by: Jun Zhao <barryjzhao@tencent.com>
9e011abad7