diff --git a/libavcodec/mpeg12enc.c b/libavcodec/mpeg12enc.c
index a6663a158b..b5951e4307 100644
--- a/libavcodec/mpeg12enc.c
+++ b/libavcodec/mpeg12enc.c
@@ -1246,7 +1246,8 @@ const FFCodec ff_mpeg1video_encoder = {
     .p.supported_framerates = ff_mpeg12_frame_rate_tab + 1,
     .p.pix_fmts           = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P,
                                                            AV_PIX_FMT_NONE },
-    .p.capabilities       = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_SLICE_THREADS,
+    .p.capabilities       = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_SLICE_THREADS |
+                            AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE,
     .caps_internal        = FF_CODEC_CAP_INIT_CLEANUP,
     .p.priv_class         = &mpeg1_class,
 };
@@ -1264,7 +1265,8 @@ const FFCodec ff_mpeg2video_encoder = {
     .p.pix_fmts           = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P,
                                                            AV_PIX_FMT_YUV422P,
                                                            AV_PIX_FMT_NONE },
-    .p.capabilities       = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_SLICE_THREADS,
+    .p.capabilities       = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_SLICE_THREADS |
+                            AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE,
     .caps_internal        = FF_CODEC_CAP_INIT_CLEANUP,
     .p.priv_class         = &mpeg2_class,
 };
diff --git a/libavcodec/mpeg4videoenc.c b/libavcodec/mpeg4videoenc.c
index 27df9ba098..c3e9ebea45 100644
--- a/libavcodec/mpeg4videoenc.c
+++ b/libavcodec/mpeg4videoenc.c
@@ -1403,7 +1403,8 @@ const FFCodec ff_mpeg4_encoder = {
     FF_CODEC_ENCODE_CB(ff_mpv_encode_picture),
     .close          = ff_mpv_encode_end,
     .p.pix_fmts     = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P, AV_PIX_FMT_NONE },
-    .p.capabilities = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_SLICE_THREADS,
+    .p.capabilities = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_SLICE_THREADS |
+                      AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE,
     .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP,
     .p.priv_class   = &mpeg4enc_class,
 };
diff --git a/libavcodec/mpegvideo_enc.c b/libavcodec/mpegvideo_enc.c
index bb101612e5..0e6a4c4ec5 100644
--- a/libavcodec/mpegvideo_enc.c
+++ b/libavcodec/mpegvideo_enc.c
@@ -1952,6 +1952,7 @@ vbv_retry:
         s->total_bits     += s->frame_bits;
 
         pkt->pts = s->current_picture.f->pts;
+        pkt->duration = s->current_picture.f->duration;
         if (!s->low_delay && s->pict_type != AV_PICTURE_TYPE_B) {
             if (!s->current_picture.f->coded_picture_number)
                 pkt->dts = pkt->pts - s->dts_delta;
@@ -1960,6 +1961,14 @@ vbv_retry:
             s->reordered_pts = pkt->pts;
         } else
             pkt->dts = pkt->pts;
+
+        // the no-delay case is handled in generic code
+        if (avctx->codec->capabilities & AV_CODEC_CAP_DELAY) {
+            ret = ff_encode_reordered_opaque(avctx, pkt, s->current_picture.f);
+            if (ret < 0)
+                return ret;
+        }
+
         if (s->current_picture.f->key_frame)
             pkt->flags |= AV_PKT_FLAG_KEY;
         if (s->mb_info)