--- a/libavcodec/mpegvideo_parser.c	2026-07-08 19:57:50.463694123 +0000
+++ b/libavcodec/mpegvideo_parser.c	2026-07-08 19:58:06.834674693 +0000
@@ -34,6 +34,34 @@
     int width, height;
 };
 
+/*
+ * yauiclient/NextPVR: safety valve against a live long-running memory-growth
+ * issue observed on some broadcast MPEG-2 sources with closed-caption
+ * user_data interleaved in the picture stream.
+ *
+ * mpeg1_find_frame_end()'s frame_start_found state machine (0/1/2/3/4) can,
+ * on certain start-code sequences it wasn't validated against, fail to ever
+ * reach state 4 (frame end confirmed) or reset back to 0. When that happens
+ * this function returns END_NOT_FOUND on every subsequent call for the rest
+ * of the stream's lifetime, and ff_combine_frame() (libavcodec/parser.c)
+ * keeps av_fast_realloc()-growing pc->buffer forever, since it only resets
+ * pc->index to 0 once a real frame boundary is reported. pc->buffer is only
+ * ever freed in ff_parse_close(), which for a live stream is only reached
+ * at genuine EOF/stream teardown -- i.e. never during ordinary continuous
+ * playback.
+ *
+ * This bounds pc->index (the current accumulation depth) to a generous
+ * multiple of the largest plausible single MPEG-2 frame size. If that
+ * bound is ever exceeded without a boundary being found, force a resync:
+ * reset the state machine and report the whole accumulated buffer as a
+ * completed (likely visibly corrupt for one frame) frame so
+ * ff_combine_frame flushes and resets pc->index to 0. This should only
+ * ever trigger in the pathological stuck-forever case described above;
+ * see combine_frame_shrink.patch for the much more commonly-hit
+ * everyday-growth case.
+ */
+#define YAUI_MPV_PARSER_RESYNC_THRESHOLD (8 * 1024 * 1024)  /* 8 MiB */
+
 /**
  * Find the end of the current frame in the bitstream.
  * @return the position of the first byte of the next frame, or -1
@@ -48,6 +76,12 @@
     if (buf_size == 0)
         return 0;
 
+    if (pc->index + buf_size > YAUI_MPV_PARSER_RESYNC_THRESHOLD) {
+        pc->frame_start_found = 0;
+        pc->state             = -1;
+        return buf_size;
+    }
+
 /*
  0  frame start         -> 1/4
  1  first_SEQEXT        -> 0/2