lavfi: add life source

6 files changed, 522 insertions, 2 deletions

diff --git a/Changelog b/Changelog
index 1aa814e50c..a2a9b0ac19 100644
--- a/Changelog
+++ b/Changelog
@@ -128,6 +128,7 @@ easier to use. The changes are:
 - CRI ADX audio format demuxer
 - Playstation Portable PMP format demuxer
 - Microsoft Windows ICO demuxer
+- life source
 
 
 version 0.8:
diff --git a/doc/filters.texi b/doc/filters.texi
index 6f569b0e2f..eb1a4df77a 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -2782,6 +2782,113 @@ Some examples follow:
 frei0r_src=200x200:10:partik0l=1234 [overlay]; [in][overlay] overlay
 @end example
 
+@section life
+
+Generate a life pattern.
+
+This source is based on a generalization of John Conway's life game.
+
+The sourced input represents a life grid, each pixel represents a cell
+which can be in one of two possible states, alive or dead. Every cell
+interacts with its eight neighbours, which are the cells that are
+horizontally, vertically, or diagonally adjacent.
+
+At each interaction the grid evolves according to the adopted rule,
+which specifies the number of neighbor alive cells which will make a
+cell stay alive or born. The @option{rule} option allows to specify
+the rule to adopt.
+
+This source accepts a list of options in the form of
+@var{key}=@var{value} pairs separated by ":". A description of the
+accepted options follows.
+
+@table @option
+@item filename, f
+Set the file from which to read the initial grid state. In the file,
+each non-whitespace character is considered an alive cell, and newline
+is used to delimit the end of each row.
+
+If this option is not specified, the initial grid is generated
+randomly.
+
+@item rate, r
+Set the video rate, that is the number of frames generated per second.
+Default is 25.
+
+@item random_fill_ratio, ratio
+Set the random fill ratio for the initial random grid. It is a
+floating point number value ranging from 0 to 1, defaults to 1/PHI.
+It is ignored when a file is specified.
+
+@item random_seed, seed
+Set the seed for filling the initial random grid, must be an integer
+included between 0 and UINT32_MAX. If not specified, or if explicitly
+set to -1, the filter will try to use a good random seed on a best
+effort basis.
+
+@item rule
+Set the life rule.
+
+A rule can be specified with a code of the kind "S@var{NS}/B@var{NB}",
+where @var{NS} and @var{NB} are sequences of numbers in the range 0-8,
+@var{NS} specifies the number of alive neighbor cells which make a
+live cell stay alive, and @var{NB} the number of alive neighbor cells
+which make a dead cell to become alive (i.e. to "born").
+"s" and "b" can be used in place of "S" and "B", respectively.
+
+Alternatively a rule can be specified by an 18-bits integer. The 9
+high order bits are used to encode the next cell state if it is alive
+for each number of neighbor alive cells, the low order bits specify
+the rule for "borning" new cells. Higher order bits encode for an
+higher number of neighbor cells.
+For example the number 6153 = @code{(12<<9)+9} specifies a stay alive
+rule of 12 and a born rule of 9, which corresponds to "S23/B03".
+
+Default value is "S23/B3", which is the original Conway's game of life
+rule, and will keep a cell alive if it has 2 or 3 neighbor alive
+cells, and will born a new cell if there are three alive cells around
+a dead cell.
+
+@item size, s
+Set the size of the output video.
+
+If @option{filename} is specified, the size is set by default to the
+same size of the input file. If @option{size} is set, it must contain
+the size specified in the input file, and the initial grid defined in
+that file is centered in the larger resulting area.
+
+If a filename is not specified, the size value defaults to "320x240"
+(used for a randomly generated initial grid).
+
+@item stitch
+If set to 1, stitch the left and right grid edges together, and the
+top and bottom edges also. Defaults to 1.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Read a grid from @file{pattern}, and center it on a grid of size
+300x300 pixels:
+@example
+life=f=pattern:s=300x300
+@end example
+
+@item
+Generate a random grid of size 200x200, with a fill ratio of 2/3:
+@example
+life=ratio=2/3:s=200x200
+@end example
+
+@item
+Specify a custom rule for evolving a randomly generated grid:
+@example
+life=rule=S14/B34
+@end example
+
+@end itemize
+
 @section nullsrc, rgbtestsrc, testsrc
 
 The @code{nullsrc} source returns unprocessed video frames. It is
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 27979a3c76..7ee4d17101 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -86,6 +86,7 @@ OBJS-$(CONFIG_YADIF_FILTER)                  += vf_yadif.o
 OBJS-$(CONFIG_BUFFER_FILTER)                 += vsrc_buffer.o
 OBJS-$(CONFIG_COLOR_FILTER)                  += vsrc_color.o
 OBJS-$(CONFIG_FREI0R_SRC_FILTER)             += vf_frei0r.o
+OBJS-$(CONFIG_LIFE_FILTER)                   += vsrc_life.o
 OBJS-$(CONFIG_MANDELBROT_FILTER)             += vsrc_mandelbrot.o
 OBJS-$(CONFIG_MOVIE_FILTER)                  += src_movie.o
 OBJS-$(CONFIG_MPTESTSRC_FILTER)              += vsrc_mptestsrc.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 176cfa60f1..2fe92bdb28 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -97,6 +97,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER (BUFFER,      buffer,      vsrc);
     REGISTER_FILTER (COLOR,       color,       vsrc);
     REGISTER_FILTER (FREI0R,      frei0r_src,  vsrc);
+    REGISTER_FILTER (LIFE,        life,        vsrc);
     REGISTER_FILTER (MANDELBROT,  mandelbrot,  vsrc);
     REGISTER_FILTER (MOVIE,       movie,       vsrc);
     REGISTER_FILTER (MPTESTSRC,   mptestsrc,   vsrc);
diff --git a/libavfilter/avfilter.h b/libavfilter/avfilter.h
index 373bc7bffa..24998a65a7 100644
--- a/libavfilter/avfilter.h
+++ b/libavfilter/avfilter.h
@@ -29,8 +29,8 @@
 #include "libavutil/rational.h"
 
 #define LIBAVFILTER_VERSION_MAJOR  2
-#define LIBAVFILTER_VERSION_MINOR 50
-#define LIBAVFILTER_VERSION_MICRO  1
+#define LIBAVFILTER_VERSION_MINOR 51
+#define LIBAVFILTER_VERSION_MICRO  0
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
                                                LIBAVFILTER_VERSION_MINOR, \
diff --git a/libavfilter/vsrc_life.c b/libavfilter/vsrc_life.c
new file mode 100644
index 0000000000..79e064ab2f
--- /dev/null
+++ b/libavfilter/vsrc_life.c
@@ -0,0 +1,410 @@
+/*
+ * Copyright (c) Stefano Sabatini 2010
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * life video source, based on John Conways' Life Game
+ */
+
+/* #define DEBUG */
+
+#include "libavutil/file.h"
+#include "libavutil/lfg.h"
+#include "libavutil/opt.h"
+#include "libavutil/parseutils.h"
+#include "libavutil/random_seed.h"
+#include "avfilter.h"
+
+typedef struct {
+    const AVClass *class;
+    int w, h;
+    char *filename;
+    char *rule_str;
+    uint8_t *file_buf;
+    size_t file_bufsize;
+    char *buf[2];
+    uint8_t  buf_idx;
+    uint16_t stay_rule;         ///< encode the behavior for filled cells
+    uint16_t born_rule;         ///< encode the behavior for empty cells
+    uint64_t pts;
+    AVRational time_base;
+    char *size;                 ///< video frame size
+    char *rate;                 ///< video frame rate
+    double   random_fill_ratio;
+    uint32_t random_seed;
+    int stitch;
+    AVLFG lfg;
+} LifeContext;
+
+#define OFFSET(x) offsetof(LifeContext, x)
+
+static const AVOption life_options[] = {
+    { "filename", "set source file",  OFFSET(filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0 },
+    { "f",        "set source file",  OFFSET(filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0 },
+    { "size",     "set video size",   OFFSET(size),     AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0 },
+    { "s",        "set video size",   OFFSET(size),     AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0 },
+    { "rate",     "set video rate",   OFFSET(rate),     AV_OPT_TYPE_STRING, {.str = "25"}, 0, 0 },
+    { "r",        "set video rate",   OFFSET(rate),     AV_OPT_TYPE_STRING, {.str = "25"}, 0, 0 },
+    { "rule",     "set rule",         OFFSET(rule_str), AV_OPT_TYPE_STRING, {.str = "B3/S23"}, CHAR_MIN, CHAR_MAX },
+    { "random_fill_ratio", "set fill ratio for filling initial grid randomly", OFFSET(random_fill_ratio), AV_OPT_TYPE_DOUBLE, {.dbl=1/M_PHI}, 0, 1 },
+    { "ratio",             "set fill ratio for filling initial grid randomly", OFFSET(random_fill_ratio), AV_OPT_TYPE_DOUBLE, {.dbl=1/M_PHI}, 0, 1 },
+    { "random_seed", "set the seed for filling the initial grid randomly", OFFSET(random_seed), AV_OPT_TYPE_INT, {.dbl=-1}, -1, UINT32_MAX },
+    { "seed",        "set the seed for filling the initial grid randomly", OFFSET(random_seed), AV_OPT_TYPE_INT, {.dbl=-1}, -1, UINT32_MAX },
+    { "stitch",      "stitch boundaries", OFFSET(stitch), AV_OPT_TYPE_INT, {.dbl=1}, 0, 1 },
+    { NULL },
+};
+
+static const char *life_get_name(void *ctx)
+{
+    return "life";
+}
+
+static const AVClass life_class = {
+    "LifeContext",
+    life_get_name,
+    life_options
+};
+
+static int parse_rule(uint16_t *born_rule, uint16_t *stay_rule,
+                      const char *rule_str, void *log_ctx)
+{
+    char *tail;
+    const char *p = rule_str;
+    *born_rule = 0;
+    *stay_rule = 0;
+
+    if (strchr("bBsS", *p)) {
+        /* parse rule as a Born / Stay Alive code, see
+         * http://en.wikipedia.org/wiki/Conway%27s_Game_of_Life */
+        do {
+            uint16_t *rule = (*p == 'b' || *p == 'B') ? born_rule : stay_rule;
+            p++;
+            while (*p >= '0' && *p <= '8') {
+                *rule += 1<<(*p - '0');
+                p++;
+            }
+            if (*p != '/')
+                break;
+            p++;
+        } while (strchr("bBsS", *p));
+
+        if (*p)
+            goto error;
+    } else {
+        /* parse the rule as a number, expressed in the form STAY|(BORN<<9),
+         * where STAY and DEATH encode the corresponding 9-bits rule */
+        long int rule = strtol(rule_str, &tail, 10);
+        if (*tail)
+            goto error;
+        *born_rule  = ((1<<9)-1) & rule;
+        *stay_rule = rule >> 9;
+    }
+
+    return 0;
+
+error:
+    av_log(log_ctx, AV_LOG_ERROR, "Invalid rule code '%s' provided\n", rule_str);
+    return AVERROR(EINVAL);
+}
+
+#ifdef DEBUG
+static void show_life_grid(AVFilterContext *ctx)
+{
+    LifeContext *life = ctx->priv;
+    int i, j;
+
+    char *line = av_malloc(life->w + 1);
+    if (!line)
+        return;
+    for (i = 0; i < life->h; i++) {
+        for (j = 0; j < life->w; j++)
+            line[j] = life->buf[life->buf_idx][i*life->w + j] ? '@' : ' ';
+        line[j] = 0;
+        av_log(ctx, AV_LOG_DEBUG, "%3d: %s\n", i, line);
+    }
+    av_free(line);
+}
+#endif
+
+static int init_pattern_from_file(AVFilterContext *ctx)
+{
+    LifeContext *life = ctx->priv;
+    char *p;
+    int ret, i, i0, j, h = 0, w, max_w = 0;
+
+    if ((ret = av_file_map(life->filename, &life->file_buf, &life->file_bufsize,
+                           0, ctx)) < 0)
+        return ret;
+
+    /* prescan file to get the number of lines and the maximum width */
+    w = 0;
+    for (i = 0; i < life->file_bufsize; i++) {
+        if (life->file_buf[i] == '\n') {
+            h++; max_w = FFMAX(w, max_w); w = 0;
+        } else {
+            w++;
+        }
+    }
+    av_log(ctx, AV_LOG_DEBUG, "h:%d max_w:%d\n", h, max_w);
+
+    if (life->size) {
+        if (max_w > life->w || h > life->h) {
+            av_log(ctx, AV_LOG_ERROR,
+                   "The specified size is %dx%d which cannot contain the provided file size of %dx%d\n",
+                   life->w, life->h, max_w, h);
+            return AVERROR(EINVAL);
+        }
+    } else {
+        /* size was not specified, set it to size of the grid */
+        life->w = max_w;
+        life->h = h;
+    }
+
+    if (!(life->buf[0] = av_mallocz(sizeof(char) * life->h * life->w)) ||
+        !(life->buf[1] = av_mallocz(sizeof(char) * life->h * life->w))) {
+        av_free(life->buf[0]);
+        av_free(life->buf[1]);
+        return AVERROR(ENOMEM);
+    }
+
+    /* fill buf[0] */
+    p = life->file_buf;
+    for (i0 = 0, i = (life->h - h)/2; i0 < h; i0++, i++) {
+        for (j = (life->w - max_w)/2;; j++) {
+            av_log(ctx, AV_LOG_DEBUG, "%d:%d %c\n", i, j, *p == '\n' ? 'N' : *p);
+            if (*p == '\n') {
+                p++; break;
+            } else
+                life->buf[0][i*life->w + j] = !!isgraph(*(p++));
+        }
+    }
+    life->buf_idx = 0;
+
+    return 0;
+}
+
+static int init(AVFilterContext *ctx, const char *args, void *opaque)
+{
+    LifeContext *life = ctx->priv;
+    AVRational frame_rate;
+    int ret;
+
+    life->class = &life_class;
+    av_opt_set_defaults(life);
+
+    if ((ret = av_set_options_string(life, args, "=", ":")) < 0) {
+        av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
+        return ret;
+    }
+
+    if ((ret = av_parse_video_rate(&frame_rate, life->rate)) < 0) {
+        av_log(ctx, AV_LOG_ERROR, "Invalid frame rate: %s\n", life->rate);
+        return AVERROR(EINVAL);
+    }
+
+    if (!life->size && !life->filename)
+        av_opt_set(life, "size", "320x240", 0);
+
+    if (life->size &&
+        (ret = av_parse_video_size(&life->w, &life->h, life->size)) < 0) {
+        av_log(ctx, AV_LOG_ERROR, "Invalid frame size: %s\n", life->size);
+        return ret;
+    }
+
+    if ((ret = parse_rule(&life->born_rule, &life->stay_rule, life->rule_str, ctx)) < 0)
+        return ret;
+
+    life->time_base.num = frame_rate.den;
+    life->time_base.den = frame_rate.num;
+
+    if (!life->filename) {
+        /* fill the grid randomly */
+        int i;
+
+        if (!(life->buf[0] = av_mallocz(sizeof(char) * life->h * life->w)) ||
+            !(life->buf[1] = av_mallocz(sizeof(char) * life->h * life->w))) {
+            av_free(life->buf[0]);
+            av_free(life->buf[1]);
+            return AVERROR(ENOMEM);
+        }
+        if (life->random_seed == -1)
+            life->random_seed = av_get_random_seed();
+
+        av_lfg_init(&life->lfg, life->random_seed);
+
+        for (i = 0; i < life->w * life->h; i++) {
+            double r = (double)av_lfg_get(&life->lfg) / UINT32_MAX;
+            if (r <= life->random_fill_ratio)
+                life->buf[0][i] = 1;
+        }
+        life->buf_idx = 0;
+    } else {
+        if ((ret = init_pattern_from_file(ctx)) < 0)
+            return ret;
+    }
+
+    av_log(ctx, AV_LOG_INFO,
+           "s:%dx%d r:%d/%d rule:%s stay_rule:%d born_rule:%d stitch:%d\n",
+           life->w, life->h, frame_rate.num, frame_rate.den,
+           life->rule_str, life->stay_rule, life->born_rule, life->stitch);
+    return 0;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+    LifeContext *life = ctx->priv;
+
+    av_file_unmap(life->file_buf, life->file_bufsize);
+    av_freep(&life->rule_str);
+    av_freep(&life->buf[0]);
+    av_freep(&life->buf[1]);
+}
+
+static int config_props(AVFilterLink *outlink)
+{
+    LifeContext *life = outlink->src->priv;
+
+    outlink->w = life->w;
+    outlink->h = life->h;
+    outlink->time_base = life->time_base;
+
+    return 0;
+}
+
+static void evolve(AVFilterContext *ctx)
+{
+    LifeContext *life = ctx->priv;
+    int i, j, v;
+    uint8_t *oldbuf = life->buf[ life->buf_idx];
+    uint8_t *newbuf = life->buf[!life->buf_idx];
+
+    enum { NW, N, NE, W, E, SW, S, SE };
+
+    /* evolve the grid */
+    for (i = 0; i < life->h; i++) {
+        for (j = 0; j < life->w; j++) {
+            int pos[8][2], n;
+            if (life->stitch) {
+                pos[NW][0] = (i-1) < 0 ? life->h-1 : i-1; pos[NW][1] = (j-1) < 0 ? life->w-1 : j-1;
+                pos[N ][0] = (i-1) < 0 ? life->h-1 : i-1; pos[N ][1] =                         j  ;
+                pos[NE][0] = (i-1) < 0 ? life->h-1 : i-1; pos[NE][1] = (j+1) == life->w ?  0 : j+1;
+                pos[W ][0] =                         i  ; pos[W ][1] = (j-1) < 0 ? life->w-1 : j-1;
+                pos[E ][0] =                         i  ; pos[E ][1] = (j+1) == life->w ? 0  : j+1;
+                pos[SW][0] = (i+1) == life->h ?  0 : i+1; pos[SW][1] = (j-1) < 0 ? life->w-1 : j-1;
+                pos[S ][0] = (i+1) == life->h ?  0 : i+1; pos[S ][1] =                         j  ;
+                pos[SE][0] = (i+1) == life->h ?  0 : i+1; pos[SE][1] = (j+1) == life->w ?  0 : j+1;
+            } else {
+                pos[NW][0] = (i-1) < 0 ? -1        : i-1; pos[NW][1] = (j-1) < 0 ? -1        : j-1;
+                pos[N ][0] = (i-1) < 0 ? -1        : i-1; pos[N ][1] =                         j  ;
+                pos[NE][0] = (i-1) < 0 ? -1        : i-1; pos[NE][1] = (j+1) == life->w ? -1 : j+1;
+                pos[W ][0] =                         i  ; pos[W ][1] = (j-1) < 0 ? -1        : j-1;
+                pos[E ][0] =                         i  ; pos[E ][1] = (j+1) == life->w ? -1 : j+1;
+                pos[SW][0] = (i+1) == life->h ? -1 : i+1; pos[SW][1] = (j-1) < 0 ? -1        : j-1;
+                pos[S ][0] = (i+1) == life->h ? -1 : i+1; pos[S ][1] =                         j  ;
+                pos[SE][0] = (i+1) == life->h ? -1 : i+1; pos[SE][1] = (j+1) == life->w ? -1 : j+1;
+            }
+
+            /* compute the number of live neighbor cells */
+            n = (pos[NW][0] == -1 || pos[NW][1] == -1 ? 0 : oldbuf[pos[NW][0]*life->w + pos[NW][1]]) +
+                (pos[N ][0] == -1 || pos[N ][1] == -1 ? 0 : oldbuf[pos[N ][0]*life->w + pos[N ][1]]) +
+                (pos[NE][0] == -1 || pos[NE][1] == -1 ? 0 : oldbuf[pos[NE][0]*life->w + pos[NE][1]]) +
+                (pos[W ][0] == -1 || pos[W ][1] == -1 ? 0 : oldbuf[pos[W ][0]*life->w + pos[W ][1]]) +
+                (pos[E ][0] == -1 || pos[E ][1] == -1 ? 0 : oldbuf[pos[E ][0]*life->w + pos[E ][1]]) +
+                (pos[SW][0] == -1 || pos[SW][1] == -1 ? 0 : oldbuf[pos[SW][0]*life->w + pos[SW][1]]) +
+                (pos[S ][0] == -1 || pos[S ][1] == -1 ? 0 : oldbuf[pos[S ][0]*life->w + pos[S ][1]]) +
+                (pos[SE][0] == -1 || pos[SE][1] == -1 ? 0 : oldbuf[pos[SE][0]*life->w + pos[SE][1]]);
+            v = !!(1<<n & (oldbuf[i*life->w + j] ? life->stay_rule : life->born_rule));
+            av_dlog(ctx, "i:%d j:%d live_neighbors:%d cell:%d -> cell:%d\n", i, j, n, oldbuf[i*life->w + j], v);
+            newbuf[i*life->w+j] = v;
+        }
+    }
+
+    life->buf_idx = !life->buf_idx;
+}
+
+static void fill_picture(AVFilterContext *ctx, AVFilterBufferRef *picref)
+{
+    LifeContext *life = ctx->priv;
+    uint8_t *buf = life->buf[life->buf_idx];
+    int i, j, k;
+
+    /* fill the output picture with the old grid buffer */
+    for (i = 0; i < life->h; i++) {
+        uint8_t byte = 0;
+        uint8_t *p = picref->data[0] + i * picref->linesize[0];
+        for (k = 0, j = 0; j < life->w; j++) {
+            byte |= buf[i*life->w+j]<<(7-k++);
+            if (k==8 || j == life->w-1) {
+                k = 0;
+                *p++ = byte;
+                byte = 0;
+            }
+        }
+    }
+}
+
+static int request_frame(AVFilterLink *outlink)
+{
+    LifeContext *life = outlink->src->priv;
+    AVFilterBufferRef *picref = avfilter_get_video_buffer(outlink, AV_PERM_WRITE, life->w, life->h);
+    picref->video->sample_aspect_ratio = (AVRational) {1, 1};
+    picref->pts = life->pts++;
+    picref->pos = -1;
+
+    fill_picture(outlink->src, picref);
+    evolve(outlink->src);
+#ifdef DEBUG
+    show_life_grid(outlink->src);
+#endif
+
+    avfilter_start_frame(outlink, avfilter_ref_buffer(picref, ~0));
+    avfilter_draw_slice(outlink, 0, life->h, 1);
+    avfilter_end_frame(outlink);
+    avfilter_unref_buffer(picref);
+
+    return 0;
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+    static const enum PixelFormat pix_fmts[] = { PIX_FMT_MONOBLACK, PIX_FMT_NONE };
+    avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
+    return 0;
+}
+
+AVFilter avfilter_vsrc_life = {
+    .name        = "life",
+    .description = NULL_IF_CONFIG_SMALL("Create life."),
+    .priv_size = sizeof(LifeContext),
+    .init      = init,
+    .uninit    = uninit,
+    .query_formats = query_formats,
+
+    .inputs    = (const AVFilterPad[]) {
+        { .name = NULL}
+    },
+    .outputs   = (const AVFilterPad[]) {
+        { .name            = "default",
+          .type            = AVMEDIA_TYPE_VIDEO,
+          .request_frame   = request_frame,
+          .config_props    = config_props },
+        { .name = NULL}
+    },
+};