mov: fix seek to next root atom in fragmented mp4

If some but not all moof's are referenced in an sidx, whole fragments
were being skipped.

Fixes tickets 7377, 7389, and 8502

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

diff --git a/libavformat/mov.c b/libavformat/mov.c
index 32f51e6a4cd252ca2848d988c943d643cbf85ca6..eb9a8714a0415f94a8773054e29f41d126f2edbd 100644 (file)
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -7734,7 +7734,8 @@ static int mov_switch_root(AVFormatContext *s, int64_t target, int index)
     mov->next_root_atom = 0;
     if (index < 0 || index >= mov->frag_index.nb_items)
         index = search_frag_moof_offset(&mov->frag_index, target);
-    if (index < mov->frag_index.nb_items) {
+    if (index < mov->frag_index.nb_items &&
+        mov->frag_index.item[index].moof_offset == target) {
         if (index + 1 < mov->frag_index.nb_items)
             mov->next_root_atom = mov->frag_index.item[index + 1].moof_offset;
         if (mov->frag_index.item[index].headers_read)