diff --git a/Changelog b/Changelog
index e76b324..880f10a 100644
--- a/Changelog
+++ b/Changelog
@@ -2,6 +2,7 @@ Entries are sorted chronologically from oldest to youngest within each release,
 releases are sorted from youngest to oldest.
 
 version <next>:
+- framestep filter: add blend parameter for motion blur effect
 
 version 3.3:
 - CrystalHD decoder moved to new decode API
diff --git a/doc/filters.texi b/doc/filters.texi
index bc37e66..3ccb727 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -8246,6 +8246,13 @@ This filter accepts the following option:
 @item step
 Select frame after every @code{step} frames.
 Allowed values are positive integers higher than 0. Default value is @code{1}.
+@item blend
+Blend @code{blend} consequentive frames on every step,
+to produce a motion blur effect.
+Allowed values are positive integers between @code{1} and @code{step},
+where @code{1} corresponds to no motion blur, and @code{step}
+corresponds to maximal motion blur.
+Default value is @code{1}.
 @end table
 
 @anchor{frei0r}
diff --git a/libavfilter/vf_framestep.c b/libavfilter/vf_framestep.c
index 8102e7c..d68ed2d 100644
--- a/libavfilter/vf_framestep.c
+++ b/libavfilter/vf_framestep.c
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2012 Stefano Sabatini
+ * Copyright (c) 2017 Matthias C. M. Troffaes
  *
  * This file is part of FFmpeg.
  *
@@ -24,13 +25,25 @@
  */
 
 #include "libavutil/opt.h"
+#include "libavutil/pixdesc.h"
 #include "avfilter.h"
 #include "internal.h"
 #include "video.h"
 
 typedef struct NullContext {
     const AVClass *class;
-    int frame_step;
+    int frame_step;     ///< step size in frames
+    int frame_blend;    ///< how many frames to blend on each step
+    int nb_planes;      ///< number of planes in the pixel format
+    int planewidth[4];  ///< width of each plane (after subsampling)
+    int planeheight[4]; ///< height of each plane (after subsampling)
+    int linesize[4];    ///< linesize of buffer in bytes
+    uint32_t *data[4];  ///< buffer for blending input frames
+
+    void (*blend_set)(AVFilterContext *ctx, AVFrame *in, int plane);
+    void (*blend_add)(AVFilterContext *ctx, AVFrame *in, int plane);
+    void (*blend_div)(AVFilterContext *ctx, AVFrame *in, int plane);
+    int (*filter_frame)(AVFilterLink *inlink, AVFrame *in);
 } FrameStepContext;
 
 #define OFFSET(x) offsetof(FrameStepContext, x)
@@ -38,43 +51,229 @@ typedef struct NullContext {
 
 static const AVOption framestep_options[] = {
     { "step", "set frame step",  OFFSET(frame_step), AV_OPT_TYPE_INT, {.i64=1}, 1, INT_MAX, FLAGS},
+    { "blend", "number of frames to blend per step",  OFFSET(frame_blend), AV_OPT_TYPE_INT, {.i64=1}, 1, 65535, FLAGS},
     { NULL },
 };
 
 AVFILTER_DEFINE_CLASS(framestep);
 
+#define DEFINE_BLEND(NAME, TYPE, DECL, EXPR)                                   \
+static void blend_##NAME##_##TYPE(AVFilterContext *ctx, AVFrame *in, int plane)\
+{                                                                              \
+    FrameStepContext *s = ctx->priv;                                           \
+    DECL                                                                       \
+    const int height = s->planeheight[plane];                                  \
+    const int width  = s->planewidth[plane];                                   \
+    const int stride = in->linesize[plane] / sizeof(TYPE);                     \
+    TYPE *src = (TYPE *)in->data[plane];                                       \
+    uint32_t *dst = s->data[plane];                                            \
+    int y, x;                                                                  \
+                                                                               \
+    for (y = 0; y < height; y++) {                                             \
+        for (x = 0; x < width; x++) {                                          \
+            EXPR;                                                              \
+        }                                                                      \
+        src += stride;                                                         \
+    }                                                                          \
+}
+
+#define SET_DECL
+#define SET_EXPR *dst++ = src[x]
+#define ADD_DECL
+#define ADD_EXPR *dst++ += src[x]
+#define DIV_DECL const int frame_blend = s->frame_blend;
+#define DIV_EXPR src[x] = *dst++ / frame_blend
+
+DEFINE_BLEND(set, uint8_t,  SET_DECL, SET_EXPR)
+DEFINE_BLEND(set, uint16_t, SET_DECL, SET_EXPR)
+DEFINE_BLEND(add, uint8_t,  ADD_DECL, ADD_EXPR)
+DEFINE_BLEND(add, uint16_t, ADD_DECL, ADD_EXPR)
+DEFINE_BLEND(div, uint8_t,  DIV_DECL, DIV_EXPR)
+DEFINE_BLEND(div, uint16_t, DIV_DECL, DIV_EXPR)
+
+#undef SET_DECL
+#undef SET_EXPR
+#undef ADD_DECL
+#undef ADD_EXPR
+#undef DIV_DECL
+#undef DIV_EXPR
+#undef DEFINE_BLEND
+
+static int filter_frame_generic(AVFilterLink *inlink, AVFrame *in)
+{
+    AVFilterContext *ctx = inlink->dst;
+    FrameStepContext *s = ctx->priv;
+    AVFilterLink *outlink = ctx->outputs[0];
+    AVFrame *out = NULL;
+    uint64_t frame_pos = inlink->frame_count_out % s->frame_step;
+    int direct = 0;
+
+    /* update destination frame buffer (framestep->data); we need to
+       do this even if filter is disabled because buffer might be used
+       for later frames when filter is re-enabled */
+    if (!frame_pos) {
+        /* copy first frame to destination frame buffer */
+        for (int plane = 0; plane < s->nb_planes; plane++)
+            s->blend_set(ctx, in, plane);
+    } else if (frame_pos < s->frame_blend) {
+        /* add current frame to destination frame buffer */
+        for (int plane = 0; plane < s->nb_planes; plane++)
+            s->blend_add(ctx, in, plane);
+    }
+
+    /* write frame */
+    if (ctx->is_disabled) {
+        /* filter is disabled, so pass input frame as is */
+        return ff_filter_frame(outlink, in);
+    } else if ((frame_pos + 1) == s->frame_blend) {
+        /* filter is enabled, so write when all frames are blended */
+        /* create a writable frame */
+        if (av_frame_is_writable(in)) {
+            direct = 1;
+            out = in;
+        } else {
+            out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
+            if (!out) {
+                av_frame_free(&in);
+                return AVERROR(ENOMEM);
+            }
+            av_frame_copy_props(out, in);
+        }
+        /* finalize destination frame */
+        for (int plane = 0; plane < s->nb_planes; plane++)
+            s->blend_div(ctx, out, plane);
+        /* free extra frame if created, and pass on output frame */
+        if (!direct)
+            av_frame_free(&in);
+        return ff_filter_frame(outlink, out);
+    } else {
+        av_frame_free(&in);
+        return 0;
+    }
+}
+
+/* special case of filter_frame when frame_blend is 1 */
+static int filter_frame_single(AVFilterLink *inlink, AVFrame *in)
+{
+    AVFilterContext *ctx = inlink->dst;
+    FrameStepContext *s = ctx->priv;
+
+    if (!(inlink->frame_count_out % s->frame_step) || ctx->is_disabled) {
+        return ff_filter_frame(ctx->outputs[0], in);
+    } else {
+        av_frame_free(&in);
+        return 0;
+    }
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+    static const enum AVPixelFormat pix_fmts[] = {
+        AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV411P,
+        AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P,
+        AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV444P,
+        AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P,
+        AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ420P,
+        AV_PIX_FMT_YUVJ411P,
+        AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA444P,
+        AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRAP, AV_PIX_FMT_GRAY8,
+        AV_PIX_FMT_YUV420P16, AV_PIX_FMT_YUV422P16, AV_PIX_FMT_YUV444P16,
+        AV_PIX_FMT_YUVA420P16, AV_PIX_FMT_YUVA422P16, AV_PIX_FMT_YUVA444P16,
+        AV_PIX_FMT_GBRP16, AV_PIX_FMT_GRAY16,
+        AV_PIX_FMT_NV12, AV_PIX_FMT_NV21,
+        AV_PIX_FMT_NONE
+    };
+    FrameStepContext *s = ctx->priv;
+    AVFilterFormats *fmts_list = NULL;
+
+    if (s->frame_blend == 1) {
+        fmts_list = ff_all_formats(AVMEDIA_TYPE_VIDEO);
+    } else {
+        fmts_list = ff_make_format_list(pix_fmts);
+    }
+    if (!fmts_list)
+        return AVERROR(ENOMEM);
+    return ff_set_common_formats(ctx, fmts_list);
+}
+
+static int config_input_props(AVFilterLink *inlink)
+{
+    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
+    const AVFilterContext *ctx = inlink->dst;
+    FrameStepContext *s = ctx->priv;
+
+    s->planewidth[0] = s->planewidth[3] = inlink->w;
+    s->planewidth[1] = s->planewidth[2] = AV_CEIL_RSHIFT(inlink->w, desc->log2_chroma_w);
+    s->planeheight[0] = s->planeheight[3] = inlink->h;
+    s->planeheight[1] = s->planeheight[2] = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
+    s->nb_planes = av_pix_fmt_count_planes(inlink->format);
+    for (int plane = 0; plane < s->nb_planes; plane++) {
+        const int planesize = s->planewidth[plane] * s->planeheight[plane];
+        s->data[plane] = av_mallocz_array(planesize, sizeof(uint32_t));
+        if (!s->data[plane])
+            return AVERROR(ENOMEM);
+    }    
+    if (s->frame_blend == 1) {
+        s->filter_frame = filter_frame_single;
+    } else {
+        s->filter_frame = filter_frame_generic;
+        if (desc->comp[0].depth == 8) {
+            s->blend_set = blend_set_uint8_t;
+            s->blend_add = blend_add_uint8_t;
+            s->blend_div = blend_div_uint8_t;
+        } else if (desc->comp[0].depth == 16) {
+            s->blend_set = blend_set_uint16_t;
+            s->blend_add = blend_add_uint16_t;
+            s->blend_div = blend_div_uint16_t;
+        } else {
+            return AVERROR(AVERROR_BUG);
+        }
+    }
+    return 0;
+}
+
 static int config_output_props(AVFilterLink *outlink)
 {
     AVFilterContext *ctx = outlink->src;
-    FrameStepContext *framestep = ctx->priv;
-    AVFilterLink *inlink = ctx->inputs[0];
+    const FrameStepContext *s = ctx->priv;
+    const AVFilterLink *inlink = ctx->inputs[0];
 
     outlink->frame_rate =
-        av_div_q(inlink->frame_rate, (AVRational){framestep->frame_step, 1});
+        av_div_q(inlink->frame_rate, (AVRational){s->frame_step, 1});
 
     av_log(ctx, AV_LOG_VERBOSE, "step:%d frame_rate:%d/%d(%f) -> frame_rate:%d/%d(%f)\n",
-           framestep->frame_step,
+           s->frame_step,
            inlink->frame_rate.num, inlink->frame_rate.den, av_q2d(inlink->frame_rate),
            outlink->frame_rate.num, outlink->frame_rate.den, av_q2d(outlink->frame_rate));
+
     return 0;
 }
 
-static int filter_frame(AVFilterLink *inlink, AVFrame *ref)
+static av_cold int init(AVFilterContext *ctx)
 {
-    FrameStepContext *framestep = inlink->dst->priv;
+    FrameStepContext *s = ctx->priv;
+    s->frame_blend = FFMIN(s->frame_blend, s->frame_step);
+    return 0;
+}
 
-    if (!(inlink->frame_count_out % framestep->frame_step)) {
-        return ff_filter_frame(inlink->dst->outputs[0], ref);
-    } else {
-        av_frame_free(&ref);
-        return 0;
-    }
+static av_cold void uninit(AVFilterContext *ctx)
+{
+    FrameStepContext *s = ctx->priv;
+    for (int plane = 0; plane < s->nb_planes; plane++)
+        av_freep(&s->data[plane]);
+}
+
+static int filter_frame(AVFilterLink *inlink, AVFrame *in)
+{
+    FrameStepContext *s = inlink->dst->priv;
+    return s->filter_frame(inlink, in);
 }
 
 static const AVFilterPad framestep_inputs[] = {
     {
         .name         = "default",
         .type         = AVMEDIA_TYPE_VIDEO,
+        .config_props = config_input_props,
         .filter_frame = filter_frame,
     },
     { NULL }
@@ -90,11 +289,14 @@ static const AVFilterPad framestep_outputs[] = {
 };
 
 AVFilter ff_vf_framestep = {
-    .name        = "framestep",
-    .description = NULL_IF_CONFIG_SMALL("Select one frame every N frames."),
-    .priv_size   = sizeof(FrameStepContext),
-    .priv_class  = &framestep_class,
-    .inputs      = framestep_inputs,
-    .outputs     = framestep_outputs,
-    .flags       = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
+    .name          = "framestep",
+    .description   = NULL_IF_CONFIG_SMALL("Select one frame every N frames."),
+    .priv_size     = sizeof(FrameStepContext),
+    .priv_class    = &framestep_class,
+    .init          = init,
+    .uninit        = uninit,
+    .query_formats = query_formats,
+    .inputs        = framestep_inputs,
+    .outputs       = framestep_outputs,
+    .flags         = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL,
 };
diff --git a/tests/fate/filter-video.mak b/tests/fate/filter-video.mak
index b40422a..216ab27 100644
--- a/tests/fate/filter-video.mak
+++ b/tests/fate/filter-video.mak
@@ -381,6 +381,11 @@ fate-filter-fps-cfr: CMD = framecrc -i $(TARGET_SAMPLES)/qtrle/apple-animation-v
 fate-filter-fps-r:   CMD = framecrc -i $(TARGET_SAMPLES)/qtrle/apple-animation-variable-fps-bug.mov -r 30 -vf fps -pix_fmt yuv420p
 fate-filter-fps:     CMD = framecrc -i $(TARGET_SAMPLES)/qtrle/apple-animation-variable-fps-bug.mov -vf fps=30 -pix_fmt yuv420p
 
+FATE_FILTER_SAMPLES-$(call ALLYES, FRAMESTEP_FILTER) += fate-filter-framestep-1 fate-filter-framestep-2 fate-filter-framestep-3
+fate-filter-framestep-1: CMD = framecrc -i $(TARGET_SAMPLES)/filter/anim.mkv -vf framestep=step=6
+fate-filter-framestep-2: CMD = framecrc -i $(TARGET_SAMPLES)/filter/anim.mkv -pix_fmt yuv420p -vf framestep=step=6:blend=3
+fate-filter-framestep-3: CMD = framecrc -i $(TARGET_SAMPLES)/filter/anim.mkv -pix_fmt yuv420p16le -vf framestep=step=6:blend=3
+
 FATE_FILTER_VSYNTH-$(call ALLYES, FORMAT_FILTER SPLIT_FILTER ALPHAEXTRACT_FILTER ALPHAMERGE_FILTER) += fate-filter-alphaextract_alphamerge_rgb
 fate-filter-alphaextract_alphamerge_rgb: tests/data/filtergraphs/alphamerge_alphaextract_rgb
 fate-filter-alphaextract_alphamerge_rgb: CMD = framecrc -c:v pgmyuv -i $(SRC) -filter_complex_script $(TARGET_PATH)/tests/data/filtergraphs/alphamerge_alphaextract_rgb
diff --git a/tests/ref/fate/filter-framestep-1 b/tests/ref/fate/filter-framestep-1
new file mode 100644
index 0000000..0a6dd19
--- /dev/null
+++ b/tests/ref/fate/filter-framestep-1
@@ -0,0 +1,17 @@
+#tb 0: 1001/4000
+#media_type 0: video
+#codec_id 0: rawvideo
+#dimensions 0: 320x180
+#sar 0: 1/1
+0,          0,          0,        1,   172800, 0x5adff92c
+0,          1,          1,        1,   172800, 0x37b7f659
+0,          2,          2,        1,   172800, 0xb4a6f1d1
+0,          3,          3,        1,   172800, 0xd596f9c6
+0,          4,          4,        1,   172800, 0xff5a015b
+0,          5,          5,        1,   172800, 0x65477f11
+0,          6,          6,        1,   172800, 0x41569400
+0,          7,          7,        1,   172800, 0xcff9ddf9
+0,          8,          8,        1,   172800, 0xd6daba1e
+0,          9,          9,        1,   172800, 0xad83bda1
+0,         10,         10,        1,   172800, 0x1518bdb3
+0,         11,         11,        1,   172800, 0xfdd1c7ca
diff --git a/tests/ref/fate/filter-framestep-2 b/tests/ref/fate/filter-framestep-2
new file mode 100644
index 0000000..d8dfb3c
--- /dev/null
+++ b/tests/ref/fate/filter-framestep-2
@@ -0,0 +1,17 @@
+#tb 0: 1001/4000
+#media_type 0: video
+#codec_id 0: rawvideo
+#dimensions 0: 320x180
+#sar 0: 1/1
+0,          0,          0,        1,    86400, 0x5a5fa606
+0,          1,          1,        1,    86400, 0xaadd94b9
+0,          2,          2,        1,    86400, 0x91879f92
+0,          3,          3,        1,    86400, 0x62e3aa29
+0,          4,          4,        1,    86400, 0xb0a5b0b4
+0,          5,          5,        1,    86400, 0x49f4cb42
+0,          6,          6,        1,    86400, 0x396befa1
+0,          7,          7,        1,    86400, 0xc30e7e5d
+0,          8,          8,        1,    86400, 0x677b4d09
+0,          9,          9,        1,    86400, 0xe7384e86
+0,         10,         10,        1,    86400, 0xf48d4e8b
+0,         11,         11,        1,    86400, 0x43834cdd
diff --git a/tests/ref/fate/filter-framestep-3 b/tests/ref/fate/filter-framestep-3
new file mode 100644
index 0000000..11ce032
--- /dev/null
+++ b/tests/ref/fate/filter-framestep-3
@@ -0,0 +1,17 @@
+#tb 0: 1001/4000
+#media_type 0: video
+#codec_id 0: rawvideo
+#dimensions 0: 320x180
+#sar 0: 1/1
+0,          0,          0,        1,   172800, 0x2c4a2095
+0,          1,          1,        1,   172800, 0x43bc1f93
+0,          2,          2,        1,   172800, 0x7e3eebc2
+0,          3,          3,        1,   172800, 0xa8e31a76
+0,          4,          4,        1,   172800, 0x60d6265f
+0,          5,          5,        1,   172800, 0x4eea61e0
+0,          6,          6,        1,   172800, 0x80c044a7
+0,          7,          7,        1,   172800, 0x730bc794
+0,          8,          8,        1,   172800, 0xbe9d4fea
+0,          9,          9,        1,   172800, 0x29006c79
+0,         10,         10,        1,   172800, 0x36135cbe
+0,         11,         11,        1,   172800, 0x40535425
