[FFmpeg-devel] [PATCH] avcodec/vvc decode: ALF filtering without CC-ALF

[Chris Warrington]

When a stream has ALF filtering enabled but not CC-ALF, the CC-ALF set indexes alf->ctb_cc_idc are being read uninitialized during ALF filtering.

This change initializes alf->ctb_cc_idc whenever ALF is enabled.

Ref. https://trac.ffmpeg.org/ticket/11325

---
 libavcodec/vvc/ctu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/vvc/ctu.c b/libavcodec/vvc/ctu.c
index a32abdeb62..c972dcc33e 100644
--- a/libavcodec/vvc/ctu.c
+++ b/libavcodec/vvc/ctu.c
@@ -2288,6 +2288,7 @@ static void alf_params(VVCLocalContext *lc, const int rx, const int ry)
     ALFParams *alf                = &CTB(fc->tab.alf, rx, ry);

     alf->ctb_flag[LUMA] = alf->ctb_flag[CB] = alf->ctb_flag[CR] = 0;
+    alf->ctb_cc_idc[0] = alf->ctb_cc_idc[1] = 0;
     if (sh->sh_alf_enabled_flag) {
         alf->ctb_flag[LUMA] = ff_vvc_alf_ctb_flag(lc, rx, ry, LUMA);
         if (alf->ctb_flag[LUMA]) {
@@ -2318,7 +2319,6 @@ static void alf_params(VVCLocalContext *lc, const int rx, const int ry)
         const uint8_t cc_enabled[] = { sh->sh_alf_cc_cb_enabled_flag, sh->sh_alf_cc_cr_enabled_flag };
         const uint8_t cc_aps_id[]  = { sh->sh_alf_cc_cb_aps_id, sh->sh_alf_cc_cr_aps_id };
         for (int i = 0; i < 2; i++) {
-            alf->ctb_cc_idc[i] = 0;
             if (cc_enabled[i]) {
                 const VVCALF *aps = fc->ps.alf_list[cc_aps_id[i]];
                 alf->ctb_cc_idc[i] = ff_vvc_alf_ctb_cc_idc(lc, rx, ry, i, aps->num_cc_filters[i]);
--
2.43.0


This message and any attachment are confidential and may be privileged or otherwise protected from disclosure. If you are not the intended recipient, please notify the sender immediately and delete this message and any attachment from your system. Do not copy them or disclose the contents to any other person.