avfilter: add xfade filter

4 files changed, 938 insertions, 1 deletions

diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 58b3077dec..72804323d5 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -441,6 +441,7 @@ OBJS-$(CONFIG_W3FDIF_FILTER)                 += vf_w3fdif.o
 OBJS-$(CONFIG_WAVEFORM_FILTER)               += vf_waveform.o
 OBJS-$(CONFIG_WEAVE_FILTER)                  += vf_weave.o
 OBJS-$(CONFIG_XBR_FILTER)                    += vf_xbr.o
+OBJS-$(CONFIG_XFADE_FILTER)                  += vf_xfade.o
 OBJS-$(CONFIG_XMEDIAN_FILTER)                += vf_xmedian.o framesync.o
 OBJS-$(CONFIG_XSTACK_FILTER)                 += vf_stack.o framesync.o
 OBJS-$(CONFIG_YADIF_FILTER)                  += vf_yadif.o yadif_common.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 6270c18ae2..f7ab2def92 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -420,6 +420,7 @@ extern AVFilter ff_vf_w3fdif;
 extern AVFilter ff_vf_waveform;
 extern AVFilter ff_vf_weave;
 extern AVFilter ff_vf_xbr;
+extern AVFilter ff_vf_xfade;
 extern AVFilter ff_vf_xmedian;
 extern AVFilter ff_vf_xstack;
 extern AVFilter ff_vf_yadif;
diff --git a/libavfilter/version.h b/libavfilter/version.h
index 03b6ce650a..8882d6aad2 100644
--- a/libavfilter/version.h
+++ b/libavfilter/version.h
@@ -30,7 +30,7 @@
 #include "libavutil/version.h"
 
 #define LIBAVFILTER_VERSION_MAJOR   7
-#define LIBAVFILTER_VERSION_MINOR  71
+#define LIBAVFILTER_VERSION_MINOR  72
 #define LIBAVFILTER_VERSION_MICRO 100
 
 
diff --git a/libavfilter/vf_xfade.c b/libavfilter/vf_xfade.c
new file mode 100644
index 0000000000..d48ee58342
--- /dev/null
+++ b/libavfilter/vf_xfade.c
@@ -0,0 +1,935 @@
+/*
+ * Copyright (c) 2020 Paul B Mahol
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser 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
+ */
+
+#include "libavutil/imgutils.h"
+#include "libavutil/eval.h"
+#include "libavutil/opt.h"
+#include "libavutil/pixfmt.h"
+#include "avfilter.h"
+#include "formats.h"
+#include "framesync.h"
+#include "internal.h"
+#include "filters.h"
+#include "video.h"
+
+enum XFadeTransitions {
+    CUSTOM = -1,
+    FADE,
+    WIPELEFT,
+    WIPERIGHT,
+    WIPEUP,
+    WIPEDOWN,
+    SLIDELEFT,
+    SLIDERIGHT,
+    SLIDEUP,
+    SLIDEDOWN,
+    CIRCLECROP,
+    RECTCROP,
+    DISTANCE,
+    FADEBLACK,
+    FADEWHITE,
+    NB_TRANSITIONS,
+};
+
+typedef struct XFadeContext {
+    const AVClass *class;
+
+    int     transition;
+    int64_t duration;
+    int64_t offset;
+    char   *custom_str;
+
+    int nb_planes;
+    int depth;
+
+    int64_t duration_pts;
+    int64_t offset_pts;
+    int64_t first_pts;
+    int64_t last_pts;
+    int64_t pts;
+    int xfade_is_over;
+    int need_second;
+    int eof[2];
+    AVFrame *xf[2];
+    int max_value;
+    uint16_t black[4];
+    uint16_t white[4];
+
+    void (*transitionf)(AVFilterContext *ctx, const AVFrame *a, const AVFrame *b, AVFrame *out, float progress,
+                        int slice_start, int slice_end, int jobnr);
+
+    AVExpr *e;
+} XFadeContext;
+
+static const char *const var_names[] = {   "X",   "Y",   "W",   "H",   "A",   "B",   "PLANE",          "P",        NULL };
+enum                                   { VAR_X, VAR_Y, VAR_W, VAR_H, VAR_A, VAR_B, VAR_PLANE, VAR_PROGRESS, VAR_VARS_NB };
+
+typedef struct ThreadData {
+    const AVFrame *xf[2];
+    AVFrame *out;
+    float progress;
+} ThreadData;
+
+static int query_formats(AVFilterContext *ctx)
+{
+    static const enum AVPixelFormat pix_fmts[] = {
+        AV_PIX_FMT_YUVA444P,
+        AV_PIX_FMT_YUVJ444P,
+        AV_PIX_FMT_YUV444P,
+        AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRAP, AV_PIX_FMT_GRAY8,
+        AV_PIX_FMT_YUVA444P9, AV_PIX_FMT_GBRP9,
+        AV_PIX_FMT_YUV444P10,
+        AV_PIX_FMT_YUVA444P10,
+        AV_PIX_FMT_GBRP10, AV_PIX_FMT_GBRAP10, AV_PIX_FMT_GRAY10,
+        AV_PIX_FMT_YUV444P12,
+        AV_PIX_FMT_YUVA444P12,
+        AV_PIX_FMT_GBRP12, AV_PIX_FMT_GBRAP12, AV_PIX_FMT_GRAY12,
+        AV_PIX_FMT_YUV444P14, AV_PIX_FMT_GBRP14,
+        AV_PIX_FMT_YUV444P16,
+        AV_PIX_FMT_YUVA444P16,
+        AV_PIX_FMT_GBRP16, AV_PIX_FMT_GBRAP16, AV_PIX_FMT_GRAY16,
+        AV_PIX_FMT_NONE
+    };
+
+    AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
+    if (!fmts_list)
+        return AVERROR(ENOMEM);
+    return ff_set_common_formats(ctx, fmts_list);
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+    XFadeContext *s = ctx->priv;
+
+    av_expr_free(s->e);
+}
+
+#define OFFSET(x) offsetof(XFadeContext, x)
+#define FLAGS (AV_OPT_FLAG_FILTERING_PARAM | AV_OPT_FLAG_VIDEO_PARAM)
+
+static const AVOption xfade_options[] = {
+    { "transition", "set cross fade transition", OFFSET(transition), AV_OPT_TYPE_INT, {.i64=FADE}, -1, NB_TRANSITIONS-1, FLAGS, "transition" },
+    {   "custom",    "custom transition",     0, AV_OPT_TYPE_CONST, {.i64=CUSTOM},    0, 0, FLAGS, "transition" },
+    {   "fade",      "fade transition",       0, AV_OPT_TYPE_CONST, {.i64=FADE},      0, 0, FLAGS, "transition" },
+    {   "wipeleft",  "wipe left transition",  0, AV_OPT_TYPE_CONST, {.i64=WIPELEFT},  0, 0, FLAGS, "transition" },
+    {   "wiperight", "wipe right transition", 0, AV_OPT_TYPE_CONST, {.i64=WIPERIGHT}, 0, 0, FLAGS, "transition" },
+    {   "wipeup",    "wipe up transition",    0, AV_OPT_TYPE_CONST, {.i64=WIPEUP},    0, 0, FLAGS, "transition" },
+    {   "wipedown",  "wipe down transition",  0, AV_OPT_TYPE_CONST, {.i64=WIPEDOWN},  0, 0, FLAGS, "transition" },
+    {   "slideleft",  "slide left transition",  0, AV_OPT_TYPE_CONST, {.i64=SLIDELEFT},  0, 0, FLAGS, "transition" },
+    {   "slideright", "slide right transition", 0, AV_OPT_TYPE_CONST, {.i64=SLIDERIGHT}, 0, 0, FLAGS, "transition" },
+    {   "slideup",    "slide up transition",    0, AV_OPT_TYPE_CONST, {.i64=SLIDEUP},    0, 0, FLAGS, "transition" },
+    {   "slidedown",  "slide down transition",  0, AV_OPT_TYPE_CONST, {.i64=SLIDEDOWN},  0, 0, FLAGS, "transition" },
+    {   "circlecrop", "circle crop transition", 0, AV_OPT_TYPE_CONST, {.i64=CIRCLECROP}, 0, 0, FLAGS, "transition" },
+    {   "rectcrop",   "rect crop transition",   0, AV_OPT_TYPE_CONST, {.i64=RECTCROP},   0, 0, FLAGS, "transition" },
+    {   "distance",   "distance transition",    0, AV_OPT_TYPE_CONST, {.i64=DISTANCE},   0, 0, FLAGS, "transition" },
+    {   "fadeblack",  "fadeblack transition",   0, AV_OPT_TYPE_CONST, {.i64=FADEBLACK},  0, 0, FLAGS, "transition" },
+    {   "fadewhite",  "fadewhite transition",   0, AV_OPT_TYPE_CONST, {.i64=FADEWHITE},  0, 0, FLAGS, "transition" },
+    { "duration", "set cross fade duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64=1000000}, 0, 60000000, FLAGS },
+    { "offset",   "set cross fade start relative to first input stream", OFFSET(offset), AV_OPT_TYPE_DURATION, {.i64=0}, INT64_MIN, INT64_MAX, FLAGS },
+    { "expr",   "set expression for custom transition", OFFSET(custom_str), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS },
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(xfade);
+
+#define CUSTOM_TRANSITION(name, type, div)                                           \
+static void custom##name##_transition(AVFilterContext *ctx,                          \
+                            const AVFrame *a, const AVFrame *b, AVFrame *out,        \
+                            float progress,                                          \
+                            int slice_start, int slice_end, int jobnr)               \
+{                                                                                    \
+    XFadeContext *s = ctx->priv;                                                     \
+    const int height = slice_end - slice_start;                                      \
+                                                                                     \
+    double values[VAR_VARS_NB];                                                      \
+    values[VAR_W] = out->width;                                                      \
+    values[VAR_H] = out->height;                                                     \
+    values[VAR_PROGRESS] = progress;                                                 \
+                                                                                     \
+    for (int p = 0; p < s->nb_planes; p++) {                                         \
+        const type *xf0 = (const type *)(a->data[p] + slice_start * a->linesize[p]); \
+        const type *xf1 = (const type *)(b->data[p] + slice_start * b->linesize[p]); \
+        type *dst = (type *)(out->data[p] + slice_start * out->linesize[p]);         \
+                                                                                     \
+        values[VAR_PLANE] = p;                                                       \
+                                                                                     \
+        for (int y = 0; y < height; y++) {                                           \
+            values[VAR_Y] = slice_start + y;                                         \
+            for (int x = 0; x < out->width; x++) {                                   \
+                values[VAR_X] = x;                                                   \
+                values[VAR_A] = xf0[x];                                              \
+                values[VAR_B] = xf1[x];                                              \
+                dst[x] = av_expr_eval(s->e, values, s);                              \
+            }                                                                        \
+                                                                                     \
+            dst += out->linesize[p] / div;                                           \
+            xf0 += a->linesize[p] / div;                                             \
+            xf1 += b->linesize[p] / div;                                             \
+        }                                                                            \
+    }                                                                                \
+}
+
+CUSTOM_TRANSITION(8, uint8_t, 1)
+CUSTOM_TRANSITION(16, uint16_t, 2)
+
+static inline float mix(float a, float b, float mix)
+{
+    return a * mix + b * (1.f - mix);
+}
+
+static inline float smoothstep(float edge0, float edge1, float x)
+{
+    float t;
+
+    t = av_clipf((x - edge0) / (edge1 - edge0), 0.f, 1.f);
+
+    return t * t * (3.f - 2.f * t);
+}
+
+#define FADE_TRANSITION(name, type, div)                                             \
+static void fade##name##_transition(AVFilterContext *ctx,                            \
+                            const AVFrame *a, const AVFrame *b, AVFrame *out,        \
+                            float progress,                                          \
+                            int slice_start, int slice_end, int jobnr)               \
+{                                                                                    \
+    XFadeContext *s = ctx->priv;                                                     \
+    const int height = slice_end - slice_start;                                      \
+                                                                                     \
+    for (int p = 0; p < s->nb_planes; p++) {                                         \
+        const type *xf0 = (const type *)(a->data[p] + slice_start * a->linesize[p]); \
+        const type *xf1 = (const type *)(b->data[p] + slice_start * b->linesize[p]); \
+        type *dst = (type *)(out->data[p] + slice_start * out->linesize[p]);         \
+                                                                                     \
+        for (int y = 0; y < height; y++) {                                           \
+            for (int x = 0; x < out->width; x++) {                                   \
+                dst[x] = mix(xf0[x], xf1[x], progress);                              \
+            }                                                                        \
+                                                                                     \
+            dst += out->linesize[p] / div;                                           \
+            xf0 += a->linesize[p] / div;                                             \
+            xf1 += b->linesize[p] / div;                                             \
+        }                                                                            \
+    }                                                                                \
+}
+
+FADE_TRANSITION(8, uint8_t, 1)
+FADE_TRANSITION(16, uint16_t, 2)
+
+#define WIPELEFT_TRANSITION(name, type, div)                                         \
+static void wipeleft##name##_transition(AVFilterContext *ctx,                        \
+                                const AVFrame *a, const AVFrame *b, AVFrame *out,    \
+                                float progress,                                      \
+                                int slice_start, int slice_end, int jobnr)           \
+{                                                                                    \
+    XFadeContext *s = ctx->priv;                                                     \
+    const int height = slice_end - slice_start;                                      \
+    const int z = out->width * progress;                                             \
+                                                                                     \
+    for (int p = 0; p < s->nb_planes; p++) {                                         \
+        const type *xf0 = (const type *)(a->data[p] + slice_start * a->linesize[p]); \
+        const type *xf1 = (const type *)(b->data[p] + slice_start * b->linesize[p]); \
+        type *dst = (type *)(out->data[p] + slice_start * out->linesize[p]);         \
+                                                                                     \
+        for (int y = 0; y < height; y++) {                                           \
+            for (int x = 0; x < out->width; x++) {                                   \
+                dst[x] = x > z ? xf1[x] : xf0[x];                                    \
+            }                                                                        \
+                                                                                     \
+            dst += out->linesize[p] / div;                                           \
+            xf0 += a->linesize[p] / div;                                             \
+            xf1 += b->linesize[p] / div;                                             \
+        }                                                                            \
+    }                                                                                \
+}
+
+WIPELEFT_TRANSITION(8, uint8_t, 1)
+WIPELEFT_TRANSITION(16, uint16_t, 2)
+
+#define WIPERIGHT_TRANSITION(name, type, div)                                        \
+static void wiperight##name##_transition(AVFilterContext *ctx,                       \
+                                 const AVFrame *a, const AVFrame *b, AVFrame *out,   \
+                                 float progress,                                     \
+                                 int slice_start, int slice_end, int jobnr)          \
+{                                                                                    \
+    XFadeContext *s = ctx->priv;                                                     \
+    const int height = slice_end - slice_start;                                      \
+    const int z = out->width * (1.f - progress);                                     \
+                                                                                     \
+    for (int p = 0; p < s->nb_planes; p++) {                                         \
+        const type *xf0 = (const type *)(a->data[p] + slice_start * a->linesize[p]); \
+        const type *xf1 = (const type *)(b->data[p] + slice_start * b->linesize[p]); \
+        type *dst = (type *)(out->data[p] + slice_start * out->linesize[p]);         \
+                                                                                     \
+        for (int y = 0; y < height; y++) {                                           \
+            for (int x = 0; x < out->width; x++) {                                   \
+                dst[x] = x > z ? xf0[x] : xf1[x];                                    \
+            }                                                                        \
+                                                                                     \
+            dst += out->linesize[p] / div;                                           \
+            xf0 += a->linesize[p] / div;                                             \
+            xf1 += b->linesize[p] / div;                                             \
+        }                                                                            \
+    }                                                                                \
+}
+
+WIPERIGHT_TRANSITION(8, uint8_t, 1)
+WIPERIGHT_TRANSITION(16, uint16_t, 2)
+
+#define WIPEUP_TRANSITION(name, type, div)                                           \
+static void wipeup##name##_transition(AVFilterContext *ctx,                          \
+                              const AVFrame *a, const AVFrame *b, AVFrame *out,      \
+                              float progress,                                        \
+                              int slice_start, int slice_end, int jobnr)             \
+{                                                                                    \
+    XFadeContext *s = ctx->priv;                                                     \
+    const int height = slice_end - slice_start;                                      \
+    const int z = out->height * progress;                                            \
+                                                                                     \
+    for (int p = 0; p < s->nb_planes; p++) {                                         \
+        const type *xf0 = (const type *)(a->data[p] + slice_start * a->linesize[p]); \
+        const type *xf1 = (const type *)(b->data[p] + slice_start * b->linesize[p]); \
+        type *dst = (type *)(out->data[p] + slice_start * out->linesize[p]);         \
+                                                                                     \
+        for (int y = 0; y < height; y++) {                                           \
+            for (int x = 0; x < out->width; x++) {                                   \
+                dst[x] = slice_start + y > z ? xf1[x] : xf0[x];                      \
+            }                                                                        \
+                                                                                     \
+            dst += out->linesize[p] / div;                                           \
+            xf0 += a->linesize[p] / div;                                             \
+            xf1 += b->linesize[p] / div;                                             \
+        }                                                                            \
+    }                                                                                \
+}
+
+WIPEUP_TRANSITION(8, uint8_t, 1)
+WIPEUP_TRANSITION(16, uint16_t, 2)
+
+#define WIPEDOWN_TRANSITION(name, type, div)                                         \
+static void wipedown##name##_transition(AVFilterContext *ctx,                        \
+                                const AVFrame *a, const AVFrame *b, AVFrame *out,    \
+                                float progress,                                      \
+                                int slice_start, int slice_end, int jobnr)           \
+{                                                                                    \
+    XFadeContext *s = ctx->priv;                                                     \
+    const int height = slice_end - slice_start;                                      \
+    const int z = out->height * (1.f - progress);                                    \
+                                                                                     \
+    for (int p = 0; p < s->nb_planes; p++) {                                         \
+        const type *xf0 = (const type *)(a->data[p] + slice_start * a->linesize[p]); \
+        const type *xf1 = (const type *)(b->data[p] + slice_start * b->linesize[p]); \
+        type *dst = (type *)(out->data[p] + slice_start * out->linesize[p]);         \
+                                                                                     \
+        for (int y = 0; y < height; y++) {                                           \
+            for (int x = 0; x < out->width; x++) {                                   \
+                dst[x] = slice_start + y > z ? xf0[x] : xf1[x];                      \
+            }                                                                        \
+                                                                                     \
+            dst += out->linesize[p] / div;                                           \
+            xf0 += a->linesize[p] / div;                                             \
+            xf1 += b->linesize[p] / div;                                             \
+        }                                                                            \
+    }                                                                                \
+}
+
+WIPEDOWN_TRANSITION(8, uint8_t, 1)
+WIPEDOWN_TRANSITION(16, uint16_t, 2)
+
+#define SLIDELEFT_TRANSITION(name, type, div)                                        \
+static void slideleft##name##_transition(AVFilterContext *ctx,                       \
+                                 const AVFrame *a, const AVFrame *b, AVFrame *out,   \
+                                 float progress,                                     \
+                                 int slice_start, int slice_end, int jobnr)          \
+{                                                                                    \
+    XFadeContext *s = ctx->priv;                                                     \
+    const int height = slice_end - slice_start;                                      \
+    const int width = out->width;                                                    \
+    const int z = -progress * width;                                                 \
+                                                                                     \
+    for (int p = 0; p < s->nb_planes; p++) {                                         \
+        const type *xf0 = (const type *)(a->data[p] + slice_start * a->linesize[p]); \
+        const type *xf1 = (const type *)(b->data[p] + slice_start * b->linesize[p]); \
+        type *dst = (type *)(out->data[p] + slice_start * out->linesize[p]);         \
+                                                                                     \
+        for (int y = 0; y < height; y++) {                                           \
+            for (int x = 0; x < width; x++) {                                        \
+                const int zx = z + x;                                                \
+                const int zz = zx % width + width * (zx < 0);                        \
+                dst[x] = (zx > 0) && (zx < width) ? xf1[zz] : xf0[zz];               \
+            }                                                                        \
+                                                                                     \
+            dst += out->linesize[p] / div;                                           \
+            xf0 += a->linesize[p] / div;                                             \
+            xf1 += b->linesize[p] / div;                                             \
+        }                                                                            \
+    }                                                                                \
+}
+
+SLIDELEFT_TRANSITION(8, uint8_t, 1)
+SLIDELEFT_TRANSITION(16, uint16_t, 2)
+
+#define SLIDERIGHT_TRANSITION(name, type, div)                                       \
+static void slideright##name##_transition(AVFilterContext *ctx,                      \
+                                  const AVFrame *a, const AVFrame *b, AVFrame *out,  \
+                                  float progress,                                    \
+                                  int slice_start, int slice_end, int jobnr)         \
+{                                                                                    \
+    XFadeContext *s = ctx->priv;                                                     \
+    const int height = slice_end - slice_start;                                      \
+    const int width = out->width;                                                    \
+    const int z = progress * width;                                                  \
+                                                                                     \
+    for (int p = 0; p < s->nb_planes; p++) {                                         \
+        const type *xf0 = (const type *)(a->data[p] + slice_start * a->linesize[p]); \
+        const type *xf1 = (const type *)(b->data[p] + slice_start * b->linesize[p]); \
+        type *dst = (type *)(out->data[p] + slice_start * out->linesize[p]);         \
+                                                                                     \
+        for (int y = 0; y < height; y++) {                                           \
+            for (int x = 0; x < out->width; x++) {                                   \
+                const int zx = z + x;                                                \
+                const int zz = zx % width + width * (zx < 0);                        \
+                dst[x] = (zx > 0) && (zx < width) ? xf1[zz] : xf0[zz];               \
+            }                                                                        \
+                                                                                     \
+            dst += out->linesize[p] / div;                                           \
+            xf0 += a->linesize[p] / div;                                             \
+            xf1 += b->linesize[p] / div;                                             \
+        }                                                                            \
+    }                                                                                \
+}
+
+SLIDERIGHT_TRANSITION(8, uint8_t, 1)
+SLIDERIGHT_TRANSITION(16, uint16_t, 2)
+
+#define SLIDEUP_TRANSITION(name, type, div)                                         \
+static void slideup##name##_transition(AVFilterContext *ctx,                        \
+                               const AVFrame *a, const AVFrame *b, AVFrame *out,    \
+                               float progress,                                      \
+                               int slice_start, int slice_end, int jobnr)           \
+{                                                                                   \
+    XFadeContext *s = ctx->priv;                                                    \
+    const int height = out->height;                                                 \
+    const int z = -progress * height;                                               \
+                                                                                    \
+    for (int p = 0; p < s->nb_planes; p++) {                                        \
+        type *dst = (type *)(out->data[p] + slice_start * out->linesize[p]);        \
+                                                                                    \
+        for (int y = slice_start; y < slice_end; y++) {                             \
+            const int zy = z + y;                                                   \
+            const int zz = zy % height + height * (zy < 0);                         \
+            const type *xf0 = (const type *)(a->data[p] + zz * a->linesize[p]);     \
+            const type *xf1 = (const type *)(b->data[p] + zz * b->linesize[p]);     \
+                                                                                    \
+            for (int x = 0; x < out->width; x++) {                                  \
+                dst[x] = (zy > 0) && (zy < height) ? xf1[x] : xf0[x];               \
+            }                                                                       \
+                                                                                    \
+            dst += out->linesize[p] / div;                                          \
+        }                                                                           \
+    }                                                                               \
+}
+
+SLIDEUP_TRANSITION(8, uint8_t, 1)
+SLIDEUP_TRANSITION(16, uint16_t, 2)
+
+#define SLIDEDOWN_TRANSITION(name, type, div)                                       \
+static void slidedown##name##_transition(AVFilterContext *ctx,                      \
+                                 const AVFrame *a, const AVFrame *b, AVFrame *out,  \
+                                 float progress,                                    \
+                                 int slice_start, int slice_end, int jobnr)         \
+{                                                                                   \
+    XFadeContext *s = ctx->priv;                                                    \
+    const int height = out->height;                                                 \
+    const int z = progress * height;                                                \
+                                                                                    \
+    for (int p = 0; p < s->nb_planes; p++) {                                        \
+        type *dst = (type *)(out->data[p] + slice_start * out->linesize[p]);        \
+                                                                                    \
+        for (int y = slice_start; y < slice_end; y++) {                             \
+            const int zy = z + y;                                                   \
+            const int zz = zy % height + height * (zy < 0);                         \
+            const type *xf0 = (const type *)(a->data[p] + zz * a->linesize[p]);     \
+            const type *xf1 = (const type *)(b->data[p] + zz * b->linesize[p]);     \
+                                                                                    \
+            for (int x = 0; x < out->width; x++) {                                  \
+                dst[x] = (zy > 0) && (zy < height) ? xf1[x] : xf0[x];               \
+            }                                                                       \
+                                                                                    \
+            dst += out->linesize[p] / div;                                          \
+        }                                                                           \
+    }                                                                               \
+}
+
+SLIDEDOWN_TRANSITION(8, uint8_t, 1)
+SLIDEDOWN_TRANSITION(16, uint16_t, 2)
+
+#define CIRCLECROP_TRANSITION(name, type, div)                                      \
+static void circlecrop##name##_transition(AVFilterContext *ctx,                     \
+                                 const AVFrame *a, const AVFrame *b, AVFrame *out,  \
+                                 float progress,                                    \
+                                 int slice_start, int slice_end, int jobnr)         \
+{                                                                                   \
+    XFadeContext *s = ctx->priv;                                                    \
+    const int width = out->width;                                                   \
+    const int height = out->height;                                                 \
+    float z = powf(2.f * fabsf(progress - 0.5f), 3.f) * hypotf(width/2, height/2);  \
+                                                                                    \
+    for (int p = 0; p < s->nb_planes; p++) {                                        \
+        const int bg = s->black[p];                                                 \
+        type *dst = (type *)(out->data[p] + slice_start * out->linesize[p]);        \
+                                                                                    \
+        for (int y = slice_start; y < slice_end; y++) {                             \
+            const type *xf0 = (const type *)(a->data[p] + y * a->linesize[p]);      \
+            const type *xf1 = (const type *)(b->data[p] + y * b->linesize[p]);      \
+                                                                                    \
+            for (int x = 0; x < width; x++) {                                       \
+                float dist = hypotf(x - width / 2, y - height / 2);                 \
+                int val = progress < 0.5f ? xf1[x] : xf0[x];                        \
+                dst[x] = (z < dist) ? bg : val;                                     \
+            }                                                                       \
+                                                                                    \
+            dst += out->linesize[p] / div;                                          \
+        }                                                                           \
+    }                                                                               \
+}
+
+CIRCLECROP_TRANSITION(8, uint8_t, 1)
+CIRCLECROP_TRANSITION(16, uint16_t, 2)
+
+#define RECTCROP_TRANSITION(name, type, div)                                        \
+static void rectcrop##name##_transition(AVFilterContext *ctx,                       \
+                                 const AVFrame *a, const AVFrame *b, AVFrame *out,  \
+                                 float progress,                                    \
+                                 int slice_start, int slice_end, int jobnr)         \
+{                                                                                   \
+    XFadeContext *s = ctx->priv;                                                    \
+    const int width = out->width;                                                   \
+    const int height = out->height;                                                 \
+    int zh = fabsf(progress - 0.5f) * height;                                       \
+    int zw = fabsf(progress - 0.5f) * width;                                        \
+                                                                                    \
+    for (int p = 0; p < s->nb_planes; p++) {                                        \
+        const int bg = s->black[p];                                                 \
+        type *dst = (type *)(out->data[p] + slice_start * out->linesize[p]);        \
+                                                                                    \
+        for (int y = slice_start; y < slice_end; y++) {                             \
+            const type *xf0 = (const type *)(a->data[p] + y * a->linesize[p]);      \
+            const type *xf1 = (const type *)(b->data[p] + y * b->linesize[p]);      \
+                                                                                    \
+            for (int x = 0; x < width; x++) {                                       \
+                int dist = FFABS(x - width  / 2) < zw &&                            \
+                           FFABS(y - height / 2) < zh;                              \
+                int val = progress < 0.5f ? xf1[x] : xf0[x];                        \
+                dst[x] = !dist ? bg : val;                                          \
+            }                                                                       \
+                                                                                    \
+            dst += out->linesize[p] / div;                                          \
+        }                                                                           \
+    }                                                                               \
+}
+
+RECTCROP_TRANSITION(8, uint8_t, 1)
+RECTCROP_TRANSITION(16, uint16_t, 2)
+
+#define DISTANCE_TRANSITION(name, type, div)                                        \
+static void distance##name##_transition(AVFilterContext *ctx,                       \
+                                 const AVFrame *a, const AVFrame *b, AVFrame *out,  \
+                                 float progress,                                    \
+                                 int slice_start, int slice_end, int jobnr)         \
+{                                                                                   \
+    XFadeContext *s = ctx->priv;                                                    \
+    const int width = out->width;                                                   \
+    const float max = s->max_value;                                                 \
+                                                                                    \
+    for (int y = slice_start; y < slice_end; y++) {                                 \
+        for (int x = 0; x < width; x++) {                                           \
+            float dist = 0.f;                                                       \
+            for (int p = 0; p < s->nb_planes; p++) {                                \
+                const type *xf0 = (const type *)(a->data[p] + y * a->linesize[p]);  \
+                const type *xf1 = (const type *)(b->data[p] + y * b->linesize[p]);  \
+                                                                                    \
+                dist += (xf0[x] / max - xf1[x] / max) *                             \
+                        (xf0[x] / max - xf1[x] / max);                              \
+            }                                                                       \
+                                                                                    \
+            dist = sqrtf(dist) <= progress;                                         \
+            for (int p = 0; p < s->nb_planes; p++) {                                \
+                const type *xf0 = (const type *)(a->data[p] + y * a->linesize[p]);  \
+                const type *xf1 = (const type *)(b->data[p] + y * b->linesize[p]);  \
+                type *dst = (type *)(out->data[p] + y * out->linesize[p]);          \
+                dst[x] = mix(mix(xf0[x], xf1[x], dist), xf1[x], progress);          \
+            }                                                                       \
+        }                                                                           \
+    }                                                                               \
+}
+
+DISTANCE_TRANSITION(8, uint8_t, 1)
+DISTANCE_TRANSITION(16, uint16_t, 2)
+
+#define FADEBLACK_TRANSITION(name, type, div)                                        \
+static void fadeblack##name##_transition(AVFilterContext *ctx,                       \
+                            const AVFrame *a, const AVFrame *b, AVFrame *out,        \
+                            float progress,                                          \
+                            int slice_start, int slice_end, int jobnr)               \
+{                                                                                    \
+    XFadeContext *s = ctx->priv;                                                     \
+    const int height = slice_end - slice_start;                                      \
+    const float phase = 0.2f;                                                        \
+                                                                                     \
+    for (int p = 0; p < s->nb_planes; p++) {                                         \
+        const type *xf0 = (const type *)(a->data[p] + slice_start * a->linesize[p]); \
+        const type *xf1 = (const type *)(b->data[p] + slice_start * b->linesize[p]); \
+        type *dst = (type *)(out->data[p] + slice_start * out->linesize[p]);         \
+        const int bg = s->black[p];                                                  \
+                                                                                     \
+        for (int y = 0; y < height; y++) {                                           \
+            for (int x = 0; x < out->width; x++) {                                   \
+                dst[x] = mix(mix(xf0[x], bg, smoothstep(1.f-phase, 1.f, progress)),  \
+                         mix(bg, xf1[x], smoothstep(phase, 1.f, progress)),          \
+                             progress);                                              \
+            }                                                                        \
+                                                                                     \
+            dst += out->linesize[p] / div;                                           \
+            xf0 += a->linesize[p] / div;                                             \
+            xf1 += b->linesize[p] / div;                                             \
+        }                                                                            \
+    }                                                                                \
+}
+
+FADEBLACK_TRANSITION(8, uint8_t, 1)
+FADEBLACK_TRANSITION(16, uint16_t, 2)
+
+#define FADEWHITE_TRANSITION(name, type, div)                                        \
+static void fadewhite##name##_transition(AVFilterContext *ctx,                       \
+                            const AVFrame *a, const AVFrame *b, AVFrame *out,        \
+                            float progress,                                          \
+                            int slice_start, int slice_end, int jobnr)               \
+{                                                                                    \
+    XFadeContext *s = ctx->priv;                                                     \
+    const int height = slice_end - slice_start;                                      \
+    const float phase = 0.2f;                                                        \
+                                                                                     \
+    for (int p = 0; p < s->nb_planes; p++) {                                         \
+        const type *xf0 = (const type *)(a->data[p] + slice_start * a->linesize[p]); \
+        const type *xf1 = (const type *)(b->data[p] + slice_start * b->linesize[p]); \
+        type *dst = (type *)(out->data[p] + slice_start * out->linesize[p]);         \
+        const int bg = s->white[p];                                                  \
+                                                                                     \
+        for (int y = 0; y < height; y++) {                                           \
+            for (int x = 0; x < out->width; x++) {                                   \
+                dst[x] = mix(mix(xf0[x], bg, smoothstep(1.f-phase, 1.f, progress)),  \
+                         mix(bg, xf1[x], smoothstep(phase, 1.f, progress)),          \
+                             progress);                                              \
+            }                                                                        \
+                                                                                     \
+            dst += out->linesize[p] / div;                                           \
+            xf0 += a->linesize[p] / div;                                             \
+            xf1 += b->linesize[p] / div;                                             \
+        }                                                                            \
+    }                                                                                \
+}
+
+FADEWHITE_TRANSITION(8, uint8_t, 1)
+FADEWHITE_TRANSITION(16, uint16_t, 2)
+
+static inline double getpix(void *priv, double x, double y, int plane, int nb)
+{
+    XFadeContext *s = priv;
+    AVFrame *in = s->xf[nb];
+    const uint8_t *src = in->data[FFMIN(plane, s->nb_planes - 1)];
+    int linesize = in->linesize[FFMIN(plane, s->nb_planes - 1)];
+    const int w = in->width;
+    const int h = in->height;
+
+    int xi, yi;
+
+    xi = av_clipd(x, 0, w - 1);
+    yi = av_clipd(y, 0, h - 1);
+
+    if (s->depth > 8) {
+        const uint16_t *src16 = (const uint16_t*)src;
+
+        linesize /= 2;
+        return src16[xi + yi * linesize];
+    } else {
+        return src[xi + yi * linesize];
+    }
+}
+
+static double a0(void *priv, double x, double y) { return getpix(priv, x, y, 0, 0); }
+static double a1(void *priv, double x, double y) { return getpix(priv, x, y, 1, 0); }
+static double a2(void *priv, double x, double y) { return getpix(priv, x, y, 2, 0); }
+static double a3(void *priv, double x, double y) { return getpix(priv, x, y, 3, 0); }
+
+static double b0(void *priv, double x, double y) { return getpix(priv, x, y, 0, 1); }
+static double b1(void *priv, double x, double y) { return getpix(priv, x, y, 1, 1); }
+static double b2(void *priv, double x, double y) { return getpix(priv, x, y, 2, 1); }
+static double b3(void *priv, double x, double y) { return getpix(priv, x, y, 3, 1); }
+
+static int config_output(AVFilterLink *outlink)
+{
+    AVFilterContext *ctx = outlink->src;
+    AVFilterLink *inlink0 = ctx->inputs[0];
+    AVFilterLink *inlink1 = ctx->inputs[1];
+    XFadeContext *s = ctx->priv;
+    const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink0->format);
+    int is_rgb;
+
+    if (inlink0->format != inlink1->format) {
+        av_log(ctx, AV_LOG_ERROR, "inputs must be of same pixel format\n");
+        return AVERROR(EINVAL);
+    }
+    if (inlink0->w != inlink1->w || inlink0->h != inlink1->h) {
+        av_log(ctx, AV_LOG_ERROR, "First input link %s parameters "
+               "(size %dx%d) do not match the corresponding "
+               "second input link %s parameters (size %dx%d)\n",
+               ctx->input_pads[0].name, inlink0->w, inlink0->h,
+               ctx->input_pads[1].name, inlink1->w, inlink1->h);
+        return AVERROR(EINVAL);
+    }
+
+    if (inlink0->time_base.num != inlink1->time_base.num ||
+        inlink0->time_base.den != inlink1->time_base.den) {
+        av_log(ctx, AV_LOG_ERROR, "First input link %s timebase "
+               "(%d/%d) do not match the corresponding "
+               "second input link %s timebase (%d/%d)\n",
+               ctx->input_pads[0].name, inlink0->time_base.num, inlink0->time_base.den,
+               ctx->input_pads[1].name, inlink1->time_base.num, inlink1->time_base.den);
+        return AVERROR(EINVAL);
+    }
+
+    outlink->w = inlink0->w;
+    outlink->h = inlink0->h;
+    outlink->time_base = inlink0->time_base;
+    outlink->sample_aspect_ratio = inlink0->sample_aspect_ratio;
+    outlink->frame_rate = inlink0->frame_rate;
+
+    s->depth = pix_desc->comp[0].depth;
+    is_rgb = !!(pix_desc->flags & AV_PIX_FMT_FLAG_RGB);
+    s->nb_planes = av_pix_fmt_count_planes(inlink0->format);
+    s->max_value = (1 << s->depth) - 1;
+    s->black[0] = 0;
+    s->black[1] = s->black[2] = is_rgb ? 0 : s->max_value / 2;
+    s->black[3] = s->max_value;
+    s->white[0] = s->white[3] = s->max_value;
+    s->white[1] = s->white[2] = is_rgb ? s->max_value : s->max_value / 2;
+
+    s->first_pts = s->last_pts = s->pts = AV_NOPTS_VALUE;
+
+    if (s->duration)
+        s->duration_pts = av_rescale_q(s->duration, AV_TIME_BASE_Q, outlink->time_base);
+    if (s->offset)
+        s->offset_pts = av_rescale_q(s->offset, AV_TIME_BASE_Q, outlink->time_base);
+
+    switch (s->transition) {
+    case CUSTOM:     s->transitionf = s->depth <= 8 ? custom8_transition     : custom16_transition;     break;
+    case FADE:       s->transitionf = s->depth <= 8 ? fade8_transition       : fade16_transition;       break;
+    case WIPELEFT:   s->transitionf = s->depth <= 8 ? wipeleft8_transition   : wipeleft16_transition;   break;
+    case WIPERIGHT:  s->transitionf = s->depth <= 8 ? wiperight8_transition  : wiperight16_transition;  break;
+    case WIPEUP:     s->transitionf = s->depth <= 8 ? wipeup8_transition     : wipeup16_transition;     break;
+    case WIPEDOWN:   s->transitionf = s->depth <= 8 ? wipedown8_transition   : wipedown16_transition;   break;
+    case SLIDELEFT:  s->transitionf = s->depth <= 8 ? slideleft8_transition  : slideleft16_transition;  break;
+    case SLIDERIGHT: s->transitionf = s->depth <= 8 ? slideright8_transition : slideright16_transition; break;
+    case SLIDEUP:    s->transitionf = s->depth <= 8 ? slideup8_transition    : slideup16_transition;    break;
+    case SLIDEDOWN:  s->transitionf = s->depth <= 8 ? slidedown8_transition  : slidedown16_transition;  break;
+    case CIRCLECROP: s->transitionf = s->depth <= 8 ? circlecrop8_transition : circlecrop16_transition; break;
+    case RECTCROP:   s->transitionf = s->depth <= 8 ? rectcrop8_transition   : rectcrop16_transition;   break;
+    case DISTANCE:   s->transitionf = s->depth <= 8 ? distance8_transition   : distance16_transition;   break;
+    case FADEBLACK:  s->transitionf = s->depth <= 8 ? fadeblack8_transition  : fadeblack16_transition;  break;
+    case FADEWHITE:  s->transitionf = s->depth <= 8 ? fadewhite8_transition  : fadewhite16_transition;  break;
+    }
+
+    if (s->transition == CUSTOM) {
+        static const char *const func2_names[]    = {
+            "a0", "a1", "a2", "a3",
+            "b0", "b1", "b2", "b3",
+            NULL
+        };
+        double (*func2[])(void *, double, double) = {
+            a0, a1, a2, a3,
+            b0, b1, b2, b3,
+            NULL };
+        int ret;
+
+        if (!s->custom_str)
+            return AVERROR(EINVAL);
+        ret = av_expr_parse(&s->e, s->custom_str, var_names,
+                            NULL, NULL, func2_names, func2, 0, ctx);
+        if (ret < 0)
+            return ret;
+    }
+
+    return 0;
+}
+
+static int xfade_slice(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
+{
+    XFadeContext *s = ctx->priv;
+    AVFilterLink *outlink = ctx->outputs[0];
+    ThreadData *td = arg;
+    int slice_start = (outlink->h *  jobnr   ) / nb_jobs;
+    int slice_end   = (outlink->h * (jobnr+1)) / nb_jobs;
+
+    s->transitionf(ctx, td->xf[0], td->xf[1], td->out, td->progress, slice_start, slice_end, jobnr);
+
+    return 0;
+}
+
+static int xfade_frame(AVFilterContext *ctx, AVFrame *a, AVFrame *b)
+{
+    XFadeContext *s = ctx->priv;
+    AVFilterLink *outlink = ctx->outputs[0];
+    float progress = av_clipf(1.f - ((float)(s->pts - s->first_pts - s->offset_pts) / s->duration_pts), 0.f, 1.f);
+    ThreadData td;
+    AVFrame *out;
+
+    out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
+    if (!out)
+        return AVERROR(ENOMEM);
+
+    td.xf[0] = a, td.xf[1] = b, td.out = out, td.progress = progress;
+    ctx->internal->execute(ctx, xfade_slice, &td, NULL, FFMIN(outlink->h, ff_filter_get_nb_threads(ctx)));
+
+    out->pts = s->pts;
+
+    return ff_filter_frame(outlink, out);
+}
+
+static int xfade_activate(AVFilterContext *ctx)
+{
+    XFadeContext *s = ctx->priv;
+    AVFilterLink *outlink = ctx->outputs[0];
+    AVFrame *in = NULL;
+    int ret = 0, status;
+    int64_t pts;
+
+    FF_FILTER_FORWARD_STATUS_BACK_ALL(outlink, ctx);
+
+    if (s->xfade_is_over) {
+        ret = ff_inlink_consume_frame(ctx->inputs[1], &in);
+        if (ret < 0) {
+            return ret;
+        } else if (ff_inlink_acknowledge_status(ctx->inputs[1], &status, &pts)) {
+            ff_outlink_set_status(outlink, status, s->pts);
+            return 0;
+        } else if (!ret) {
+            if (ff_outlink_frame_wanted(outlink)) {
+                ff_inlink_request_frame(ctx->inputs[1]);
+                return 0;
+            }
+        } else {
+            in->pts = (in->pts - s->last_pts) + s->pts;
+            return ff_filter_frame(outlink, in);
+        }
+    }
+
+    if (ff_inlink_queued_frames(ctx->inputs[0]) > 0) {
+        s->xf[0] = ff_inlink_peek_frame(ctx->inputs[0], 0);
+        if (s->xf[0]) {
+            if (s->first_pts == AV_NOPTS_VALUE) {
+                s->first_pts = s->xf[0]->pts;
+            }
+            s->pts = s->xf[0]->pts;
+            if (s->first_pts + s->offset_pts > s->xf[0]->pts) {
+                s->xf[0] = NULL;
+                s->need_second = 0;
+                ff_inlink_consume_frame(ctx->inputs[0], &in);
+                return ff_filter_frame(outlink, in);
+            }
+
+            s->need_second = 1;
+        }
+    }
+
+    if (s->xf[0] && ff_inlink_queued_frames(ctx->inputs[1]) > 0) {
+        ff_inlink_consume_frame(ctx->inputs[0], &s->xf[0]);
+        ff_inlink_consume_frame(ctx->inputs[1], &s->xf[1]);
+
+        s->last_pts = s->xf[1]->pts;
+        s->pts = s->xf[0]->pts;
+        if (s->xf[0]->pts - (s->first_pts + s->offset_pts) > s->duration_pts)
+            s->xfade_is_over = 1;
+        ret = xfade_frame(ctx, s->xf[0], s->xf[1]);
+        av_frame_free(&s->xf[0]);
+        av_frame_free(&s->xf[1]);
+        return ret;
+    }
+
+    if (ff_inlink_queued_frames(ctx->inputs[0]) > 0 &&
+        ff_inlink_queued_frames(ctx->inputs[1]) > 0) {
+        ff_filter_set_ready(ctx, 100);
+        return 0;
+    }
+
+    if (ff_outlink_frame_wanted(outlink)) {
+        if (!s->eof[0] && ff_outlink_get_status(ctx->inputs[0])) {
+            s->eof[0] = 1;
+            s->xfade_is_over = 1;
+        }
+        if (!s->eof[1] && ff_outlink_get_status(ctx->inputs[1])) {
+            s->eof[1] = 1;
+        }
+        if (!s->eof[0] && !s->xf[0])
+            ff_inlink_request_frame(ctx->inputs[0]);
+        if (!s->eof[1] && (s->need_second || s->eof[0]))
+            ff_inlink_request_frame(ctx->inputs[1]);
+        if (s->eof[0] && s->eof[1] && (
+            ff_inlink_queued_frames(ctx->inputs[0]) <= 0 ||
+            ff_inlink_queued_frames(ctx->inputs[1]) <= 0))
+            ff_outlink_set_status(outlink, AVERROR_EOF, AV_NOPTS_VALUE);
+        return 0;
+    }
+
+    return FFERROR_NOT_READY;
+}
+
+static const AVFilterPad xfade_inputs[] = {
+    {
+        .name          = "main",
+        .type          = AVMEDIA_TYPE_VIDEO,
+    },
+    {
+        .name          = "xfade",
+        .type          = AVMEDIA_TYPE_VIDEO,
+    },
+    { NULL }
+};
+
+static const AVFilterPad xfade_outputs[] = {
+    {
+        .name          = "default",
+        .type          = AVMEDIA_TYPE_VIDEO,
+        .config_props  = config_output,
+    },
+    { NULL }
+};
+
+AVFilter ff_vf_xfade = {
+    .name          = "xfade",
+    .description   = NULL_IF_CONFIG_SMALL("Cross fade one video with another video."),
+    .priv_size     = sizeof(XFadeContext),
+    .priv_class    = &xfade_class,
+    .query_formats = query_formats,
+    .activate      = xfade_activate,
+    .uninit        = uninit,
+    .inputs        = xfade_inputs,
+    .outputs       = xfade_outputs,
+    .flags         = AVFILTER_FLAG_SLICE_THREADS,
+};