Commit 8c3ddaf4 for libheif

commit 8c3ddaf4e0b539e010a95b317bd40ea630f91a40
Author: Dirk Farin <dirk.farin@gmail.com>
Date:   Mon Oct 26 09:06:14 2026 +0100

    svt encoder: include bytes per sample in alpha placeholder chroma size

    For high bit depth alpha, n_filled_len counted the placeholder chroma
    planes with one byte per sample. SVT-AV1 rejected the frame as too
    short ("Invalid API input buffer size detected"), so 10 bit images
    with alpha failed to encode unless row padding hid the shortfall.

diff --git a/libheif/plugins/encoder_svt.cc b/libheif/plugins/encoder_svt.cc
index bcec5684..566e34f4 100644
--- a/libheif/plugins/encoder_svt.cc
+++ b/libheif/plugins/encoder_svt.cc
@@ -1144,7 +1144,7 @@ static heif_error svt_encode_sequence_frame(void* encoder_raw, const heif_image*
       }
     }

-    input_buffer.n_filled_len += 2 * uvWidth * uvHeight;
+    input_buffer.n_filled_len += 2 * uvWidth * uvHeight * bytesPerPixel;
     input_picture_buffer->cb_stride = uvWidth;
     input_picture_buffer->cr_stride = uvWidth;