From 2972216a02d15477b7772d878ab129aa0a6f0488 Mon Sep 17 00:00:00 2001
From: dailz <dailz@example.com>
Date: Wed, 15 Apr 2026 15:01:06 +0800
Subject: [PATCH] fix(avhw): specify format=nv12 output for scale_vaapi filter

scale_vaapi defaults to the input sw_format (RGBZ) when no output format
is specified. h264_vaapi encoder only supports NV12/YUV formats.
Adding format=nv12 ensures the filter outputs the correct color format
for hardware encoding.
---
 src/avhw.rs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/avhw.rs b/src/avhw.rs
index a048575..31dd9db 100644
--- a/src/avhw.rs
+++ b/src/avhw.rs
@@ -518,7 +518,11 @@ fn build_filter_graph(
     }
 
     // scale_vaapi: hardware scaling and colourspace conversion (keeps original dimensions)
-    let mut scale_ctx = graph.add(&scale_vaapi, "scale", &format!("{width}:{height}"))?;
+    let mut scale_ctx = graph.add(
+        &scale_vaapi,
+        "scale",
+        &format!("{width}:{height}:format=nv12"),
+    )?;
     // SAFETY: scale_vaapi needs hw_device_ctx for VAAPI device access.
     unsafe {
         (*scale_ctx.as_mut_ptr()).hw_device_ctx = hw_dev.ref_clone();