mpdecimate-vfr.patch

diff --git a/libavcodec/libvpxenc.c b/libavcodec/libvpxenc.c
index 992122c..0962472 100644
--- a/libavcodec/libvpxenc.c
+++ b/libavcodec/libvpxenc.c
@@ -685,6 +685,7 @@ static int storeframe(AVCodecContext *avctx, struct FrameListData *cx_frame,
         int pict_type;
         memcpy(pkt->data, cx_frame->buf, pkt->size);
         pkt->pts = pkt->dts = cx_frame->pts;
+        pkt->duration = cx_frame->duration;
 #if FF_API_CODED_FRAME
 FF_DISABLE_DEPRECATION_WARNINGS
         avctx->coded_frame->pts       = cx_frame->pts;
@@ -863,6 +864,7 @@ static int vp8_encode(AVCodecContext *avctx, AVPacket *pkt,
     struct vpx_image *rawimg = NULL;
     struct vpx_image *rawimg_alpha = NULL;
     int64_t timestamp = 0;
+    int64_t duration = avctx->ticks_per_frame;
     int res, coded_size;
     vpx_enc_frame_flags_t flags = 0;
 
@@ -896,10 +898,12 @@ static int vp8_encode(AVCodecContext *avctx, AVPacket *pkt,
         timestamp                   = frame->pts;
         if (frame->pict_type == AV_PICTURE_TYPE_I)
             flags |= VPX_EFLAG_FORCE_KF;
+        if (frame->pkt_duration > 0)
+            duration = frame->pkt_duration;
     }
 
     res = vpx_codec_encode(&ctx->encoder, rawimg, timestamp,
-                           avctx->ticks_per_frame, flags, ctx->deadline);
+                           duration, flags, ctx->deadline);
     if (res != VPX_CODEC_OK) {
         log_encoder_error(avctx, "Error encoding frame");
         return AVERROR_INVALIDDATA;
@@ -907,7 +911,7 @@ static int vp8_encode(AVCodecContext *avctx, AVPacket *pkt,
 
     if (ctx->is_alpha) {
         res = vpx_codec_encode(&ctx->encoder_alpha, rawimg_alpha, timestamp,
-                               avctx->ticks_per_frame, flags, ctx->deadline);
+                               duration, flags, ctx->deadline);
         if (res != VPX_CODEC_OK) {
             log_encoder_error(avctx, "Error encoding alpha frame");
             return AVERROR_INVALIDDATA;
diff --git a/libavfilter/vf_mpdecimate.c b/libavfilter/vf_mpdecimate.c
index 25efacf..3a13d2c 100644
--- a/libavfilter/vf_mpdecimate.c
+++ b/libavfilter/vf_mpdecimate.c
@@ -196,17 +196,22 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *cur)
 {
     DecimateContext *decimate = inlink->dst->priv;
     AVFilterLink *outlink = inlink->dst->outputs[0];
+    AVFrame *out;
     int ret;
 
     if (decimate->ref && decimate_frame(inlink->dst, cur, decimate->ref)) {
         decimate->drop_count = FFMAX(1, decimate->drop_count+1);
     } else {
-        av_frame_free(&decimate->ref);
+        if (decimate->ref) {
+            out = av_frame_clone(decimate->ref);
+            out->pkt_duration = cur->pts - out->pts;
+            av_frame_free(&decimate->ref);
+
+            if ((ret = ff_filter_frame(outlink, out)) < 0)
+                return ret;
+        }
         decimate->ref = cur;
         decimate->drop_count = FFMIN(-1, decimate->drop_count-1);
-
-        if ((ret = ff_filter_frame(outlink, av_frame_clone(cur))) < 0)
-            return ret;
     }
 
     av_log(inlink->dst, AV_LOG_DEBUG,
diff --git a/libavformat/matroskaenc.c b/libavformat/matroskaenc.c
index 1fb39fe..2e111e0 100644
--- a/libavformat/matroskaenc.c
+++ b/libavformat/matroskaenc.c
@@ -1676,7 +1676,7 @@ static void mkv_write_block(AVFormatContext *s, AVIOContext *pb,
         side_data_size -= 8;
     }
 
-    if ((side_data_size && additional_id == 1) || discard_padding) {
+    if (1 || (side_data_size && additional_id == 1) || discard_padding) {
         block_group = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, 0);
         blockid = MATROSKA_ID_BLOCK;
     }
@@ -1701,7 +1701,9 @@ static void mkv_write_block(AVFormatContext *s, AVIOContext *pb,
         put_ebml_sint(pb, MATROSKA_ID_DISCARDPADDING, discard_padding);
     }
 
-    if (side_data_size && additional_id == 1) {
+    put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, pkt->duration);
+
+    if (1 || (side_data_size && additional_id == 1)) {
         block_additions = start_ebml_master(pb, MATROSKA_ID_BLOCKADDITIONS, 0);
         block_more = start_ebml_master(pb, MATROSKA_ID_BLOCKMORE, 0);
         put_ebml_uint(pb, MATROSKA_ID_BLOCKADDID, 1);
@@ -1711,7 +1713,7 @@ static void mkv_write_block(AVFormatContext *s, AVIOContext *pb,
         end_ebml_master(pb, block_more);
         end_ebml_master(pb, block_additions);
     }
-    if ((side_data_size && additional_id == 1) || discard_padding) {
+    if (1 || (side_data_size && additional_id == 1) || discard_padding) {
         end_ebml_master(pb, block_group);
     }
 }