lavfi: port mcdeint filter from libmpcodecs

4 files changed, 317 insertions, 1 deletions

diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index e1affbf22a..b3e8cd3062 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -9,6 +9,7 @@ FFLIBS-$(CONFIG_ASYNCTS_FILTER)              += avresample
 FFLIBS-$(CONFIG_ATEMPO_FILTER)               += avcodec
 FFLIBS-$(CONFIG_DECIMATE_FILTER)             += avcodec
 FFLIBS-$(CONFIG_DESHAKE_FILTER)              += avcodec
+FFLIBS-$(CONFIG_MCDEINT_FILTER)              += avcodec
 FFLIBS-$(CONFIG_MOVIE_FILTER)                += avformat avcodec
 FFLIBS-$(CONFIG_MP_FILTER)                   += avcodec
 FFLIBS-$(CONFIG_PAN_FILTER)                  += swresample
@@ -150,6 +151,7 @@ OBJS-$(CONFIG_LUT3D_FILTER)                  += vf_lut3d.o
 OBJS-$(CONFIG_LUT_FILTER)                    += vf_lut.o
 OBJS-$(CONFIG_LUTRGB_FILTER)                 += vf_lut.o
 OBJS-$(CONFIG_LUTYUV_FILTER)                 += vf_lut.o
+OBJS-$(CONFIG_MCDEINT_FILTER)                += vf_mcdeint.o
 OBJS-$(CONFIG_MP_FILTER)                     += vf_mp.o
 OBJS-$(CONFIG_MPDECIMATE_FILTER)             += vf_mpdecimate.o
 OBJS-$(CONFIG_NEGATE_FILTER)                 += vf_lut.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 6130d09790..a60a55ed23 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -148,6 +148,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER(LUT,            lut,            vf);
     REGISTER_FILTER(LUTRGB,         lutrgb,         vf);
     REGISTER_FILTER(LUTYUV,         lutyuv,         vf);
+    REGISTER_FILTER(MCDEINT,        mcdeint,        vf);
     REGISTER_FILTER(MP,             mp,             vf);
     REGISTER_FILTER(MPDECIMATE,     mpdecimate,     vf);
     REGISTER_FILTER(NEGATE,         negate,         vf);
diff --git a/libavfilter/version.h b/libavfilter/version.h
index daca359caf..f727f1ccdf 100644
--- a/libavfilter/version.h
+++ b/libavfilter/version.h
@@ -30,7 +30,7 @@
 #include "libavutil/avutil.h"
 
 #define LIBAVFILTER_VERSION_MAJOR  3
-#define LIBAVFILTER_VERSION_MINOR  73
+#define LIBAVFILTER_VERSION_MINOR  74
 #define LIBAVFILTER_VERSION_MICRO 100
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
diff --git a/libavfilter/vf_mcdeint.c b/libavfilter/vf_mcdeint.c
new file mode 100644
index 0000000000..99030364a7
--- /dev/null
+++ b/libavfilter/vf_mcdeint.c
@@ -0,0 +1,313 @@
+/*
+ * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * FFmpeg is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with FFmpeg; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/**
+ * @file
+ * Motion Compensation Deinterlacer
+ * Ported from MPlayer libmpcodecs/vf_mcdeint.c.
+ *
+ * Known Issues:
+ *
+ * The motion estimation is somewhat at the mercy of the input, if the
+ * input frames are created purely based on spatial interpolation then
+ * for example a thin black line or another random and not
+ * interpolateable pattern will cause problems.
+ * Note: completely ignoring the "unavailable" lines during motion
+ * estimation did not look any better, so the most obvious solution
+ * would be to improve tfields or penalize problematic motion vectors.
+ *
+ * If non iterative ME is used then snow currently ignores the OBMC
+ * window and as a result sometimes creates artifacts.
+ *
+ * Only past frames are used, we should ideally use future frames too,
+ * something like filtering the whole movie in forward and then
+ * backward direction seems like a interesting idea but the current
+ * filter framework is FAR from supporting such things.
+ *
+ * Combining the motion compensated image with the input image also is
+ * not as trivial as it seems, simple blindly taking even lines from
+ * one and odd ones from the other does not work at all as ME/MC
+ * sometimes has nothing in the previous frames which matches the
+ * current. The current algorithm has been found by trial and error
+ * and almost certainly can be improved...
+ */
+
+#include "libavutil/opt.h"
+#include "libavutil/pixdesc.h"
+#include "libavcodec/avcodec.h"
+#include "avfilter.h"
+#include "formats.h"
+#include "internal.h"
+
+enum MCDeintMode {
+    MODE_FAST = 0,
+    MODE_MEDIUM,
+    MODE_SLOW,
+    MODE_EXTRA_SLOW,
+    MODE_NB,
+};
+
+enum MCDeintParity {
+    PARITY_TFF  =  0, ///< top field first
+    PARITY_BFF  =  1, ///< bottom field first
+};
+
+typedef struct {
+    const AVClass *class;
+    enum MCDeintMode mode;
+    enum MCDeintParity parity;
+    int qp;
+    AVCodecContext *enc_ctx;
+} MCDeintContext;
+
+#define OFFSET(x) offsetof(MCDeintContext, x)
+#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
+#define CONST(name, help, val, unit) { name, help, 0, AV_OPT_TYPE_CONST, {.i64=val}, INT_MIN, INT_MAX, FLAGS, unit }
+
+static const AVOption mcdeint_options[] = {
+    { "mode", "set mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=MODE_FAST}, 0, MODE_NB-1, FLAGS, .unit="mode" },
+    CONST("fast",       NULL, MODE_FAST,       "mode"),
+    CONST("medium",     NULL, MODE_MEDIUM,     "mode"),
+    CONST("slow",       NULL, MODE_SLOW,       "mode"),
+    CONST("extra_slow", NULL, MODE_EXTRA_SLOW, "mode"),
+
+    { "parity", "set the assumed picture field parity", OFFSET(parity), AV_OPT_TYPE_INT, {.i64=PARITY_BFF}, -1, 1, FLAGS, "parity" },
+    CONST("tff", "assume top field first",    PARITY_TFF, "parity"),
+    CONST("bff", "assume bottom field first", PARITY_BFF, "parity"),
+
+    { "qp", "set qp", OFFSET(qp), AV_OPT_TYPE_INT, {.i64=1}, INT_MIN, INT_MAX, FLAGS },
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(mcdeint);
+
+static int config_props(AVFilterLink *inlink)
+{
+    AVFilterContext *ctx = inlink->dst;
+    MCDeintContext *mcdeint = ctx->priv;
+    AVCodec *enc;
+    AVCodecContext *enc_ctx;
+    AVDictionary *opts = NULL;
+    int ret;
+
+    if (!(enc = avcodec_find_encoder(AV_CODEC_ID_SNOW))) {
+        av_log(ctx, AV_LOG_ERROR, "Snow encoder is not enabled in libavcodec\n");
+        return AVERROR(EINVAL);
+    }
+
+    mcdeint->enc_ctx = avcodec_alloc_context3(enc);
+    if (!mcdeint->enc_ctx)
+        return AVERROR(ENOMEM);
+    enc_ctx = mcdeint->enc_ctx;
+    enc_ctx->width  = inlink->w;
+    enc_ctx->height = inlink->h;
+    enc_ctx->time_base = (AVRational){1,25};  // meaningless
+    enc_ctx->gop_size = 300;
+    enc_ctx->max_b_frames = 0;
+    enc_ctx->pix_fmt = AV_PIX_FMT_YUV420P;
+    enc_ctx->flags = CODEC_FLAG_QSCALE | CODEC_FLAG_LOW_DELAY;
+    enc_ctx->strict_std_compliance = FF_COMPLIANCE_EXPERIMENTAL;
+    enc_ctx->global_quality = 1;
+    enc_ctx->me_cmp = enc_ctx->me_sub_cmp = FF_CMP_SAD;
+    enc_ctx->mb_cmp = FF_CMP_SSE;
+    av_dict_set(&opts, "memc_only", "1", 0);
+
+    switch (mcdeint->mode) {
+    case MODE_EXTRA_SLOW:
+        enc_ctx->refs = 3;
+    case MODE_SLOW:
+        enc_ctx->me_method = ME_ITER;
+    case MODE_MEDIUM:
+        enc_ctx->flags |= CODEC_FLAG_4MV;
+        enc_ctx->dia_size = 2;
+    case MODE_FAST:
+        enc_ctx->flags |= CODEC_FLAG_QPEL;
+    }
+
+    ret = avcodec_open2(enc_ctx, enc, &opts);
+    av_dict_free(&opts);
+    if (ret < 0)
+        return ret;
+
+    return 0;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+    MCDeintContext *mcdeint = ctx->priv;
+
+    if (mcdeint->enc_ctx) {
+        avcodec_close(mcdeint->enc_ctx);
+        av_freep(&mcdeint->enc_ctx);
+    }
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+    static const enum PixelFormat pix_fmts[] = {
+        AV_PIX_FMT_YUV420P, AV_PIX_FMT_NONE
+    };
+
+    ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
+
+    return 0;
+}
+
+static int filter_frame(AVFilterLink *inlink, AVFrame *inpic)
+{
+    MCDeintContext *mcdeint = inlink->dst->priv;
+    AVFilterLink *outlink = inlink->dst->outputs[0];
+    AVFrame *outpic, *frame_dec;
+    AVPacket pkt;
+    int x, y, i, ret, got_frame = 0;
+
+    outpic = ff_get_video_buffer(outlink, outlink->w, outlink->h);
+    if (!outpic) {
+        av_frame_free(&inpic);
+        return AVERROR(ENOMEM);
+    }
+    av_frame_copy_props(outpic, inpic);
+    inpic->quality = mcdeint->qp * FF_QP2LAMBDA;
+
+    av_init_packet(&pkt);
+    pkt.data = NULL;    // packet data will be allocated by the encoder
+    pkt.size = 0;
+
+    ret = avcodec_encode_video2(mcdeint->enc_ctx, &pkt, inpic, &got_frame);
+    if (ret < 0)
+        goto end;
+
+    frame_dec = mcdeint->enc_ctx->coded_frame;
+
+    for (i = 0; i < 3; i++) {
+        int is_chroma = !!i;
+        int w = FF_CEIL_RSHIFT(inlink->w, is_chroma);
+        int h = FF_CEIL_RSHIFT(inlink->h, is_chroma);
+        int fils = frame_dec->linesize[i];
+        int srcs = inpic    ->linesize[i];
+        int dsts = outpic   ->linesize[i];
+
+        for (y = 0; y < h; y++) {
+            if ((y ^ mcdeint->parity) & 1) {
+                for (x = 0; x < w; x++) {
+                    uint8_t *filp = &frame_dec->data[i][x + y*fils];
+                    uint8_t *srcp = &inpic    ->data[i][x + y*srcs];
+                    uint8_t *dstp = &outpic   ->data[i][x + y*dsts];
+
+                    if (y > 0 && y < h-1){
+                        int is_edge = x < 3 || x > w-4;
+                        int diff0 = filp[-fils] - srcp[-srcs];
+                        int diff1 = filp[+fils] - srcp[+srcs];
+                        int temp = filp[0];
+
+#define DELTA(j) av_clip(j, -x, w-1-x)
+
+#define GET_SCORE_EDGE(j)\
+   FFABS(srcp[-srcs+DELTA(-1+(j))] - srcp[+srcs+DELTA(-1-(j))])+\
+   FFABS(srcp[-srcs+DELTA(j)     ] - srcp[+srcs+DELTA(  -(j))])+\
+   FFABS(srcp[-srcs+DELTA(1+(j)) ] - srcp[+srcs+DELTA( 1-(j))])
+
+#define GET_SCORE(j)\
+   FFABS(srcp[-srcs-1+(j)] - srcp[+srcs-1-(j)])+\
+   FFABS(srcp[-srcs  +(j)] - srcp[+srcs  -(j)])+\
+   FFABS(srcp[-srcs+1+(j)] - srcp[+srcs+1-(j)])
+
+#define CHECK_EDGE(j)\
+    {   int score = GET_SCORE_EDGE(j);\
+        if (score < spatial_score){\
+            spatial_score = score;\
+            diff0 = filp[-fils+DELTA(j)]    - srcp[-srcs+DELTA(j)];\
+            diff1 = filp[+fils+DELTA(-(j))] - srcp[+srcs+DELTA(-(j))];\
+
+#define CHECK(j)\
+    {   int score = GET_SCORE(j);\
+        if (score < spatial_score){\
+            spatial_score= score;\
+            diff0 = filp[-fils+(j)] - srcp[-srcs+(j)];\
+            diff1 = filp[+fils-(j)] - srcp[+srcs-(j)];\
+
+                        if (is_edge) {
+                            int spatial_score = GET_SCORE_EDGE(0) - 1;
+                            CHECK_EDGE(-1) CHECK_EDGE(-2) }} }}
+                            CHECK_EDGE( 1) CHECK_EDGE( 2) }} }}
+                        } else {
+                            int spatial_score = GET_SCORE(0) - 1;
+                            CHECK(-1) CHECK(-2) }} }}
+                            CHECK( 1) CHECK( 2) }} }}
+                        }
+
+
+                        if (diff0 + diff1 > 0)
+                            temp -= (diff0 + diff1 - FFABS(FFABS(diff0) - FFABS(diff1)) / 2) / 2;
+                        else
+                            temp -= (diff0 + diff1 + FFABS(FFABS(diff0) - FFABS(diff1)) / 2) / 2;
+                        *filp = *dstp = temp > 255U ? ~(temp>>31) : temp;
+                    } else {
+                        *dstp = *filp;
+                    }
+                }
+            }
+        }
+
+        for (y = 0; y < h; y++) {
+            if (!((y ^ mcdeint->parity) & 1)) {
+                for (x = 0; x < w; x++) {
+                    frame_dec->data[i][x + y*fils] =
+                    outpic   ->data[i][x + y*dsts] = inpic->data[i][x + y*srcs];
+                }
+            }
+        }
+    }
+    mcdeint->parity ^= 1;
+
+end:
+    av_free_packet(&pkt);
+    av_frame_free(&inpic);
+    if (ret < 0)
+        return ret;
+    return ff_filter_frame(outlink, outpic);
+}
+
+static const AVFilterPad mcdeint_inputs[] = {
+    {
+        .name         = "default",
+        .type         = AVMEDIA_TYPE_VIDEO,
+        .filter_frame = filter_frame,
+        .config_props = config_props,
+    },
+    { NULL }
+};
+
+static const AVFilterPad mcdeint_outputs[] = {
+    {
+        .name = "default",
+        .type = AVMEDIA_TYPE_VIDEO,
+    },
+    { NULL }
+};
+
+AVFilter avfilter_vf_mcdeint = {
+    .name          = "mcdeint",
+    .description   = NULL_IF_CONFIG_SMALL("Apply motion compensating deinterlacing."),
+    .priv_size     = sizeof(MCDeintContext),
+    .uninit        = uninit,
+    .query_formats = query_formats,
+    .inputs        = mcdeint_inputs,
+    .outputs       = mcdeint_outputs,
+    .priv_class    = &mcdeint_class,
+};