| 
							- /*
 -  * 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/intreadwrite.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;
 - 
 -     /**
 -      * The two grid state buffers.
 -      *
 -      * A 0xFF (ALIVE_CELL) value means the cell is alive (or new born), while
 -      * the decreasing values from 0xFE to 0 means the cell is dead; the range
 -      * of values is used for the slow death effect, or mold (0xFE means dead,
 -      * 0xFD means very dead, 0xFC means very very dead... and 0x00 means
 -      * definitely dead/mold).
 -      */
 -     uint8_t *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;
 -     int mold;
 -     char  *life_color_str;
 -     char *death_color_str;
 -     char  *mold_color_str;
 -     uint8_t  life_color[4];
 -     uint8_t death_color[4];
 -     uint8_t  mold_color[4];
 -     AVLFG lfg;
 -     void (*draw)(AVFilterContext*, AVFilterBufferRef*);
 - } LifeContext;
 - 
 - #define ALIVE_CELL 0xFF
 - #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 },
 -     { "mold",        "set mold speed for dead cells", OFFSET(mold), AV_OPT_TYPE_INT, {.dbl=0}, 0, 0xFF },
 -     { "life_color",  "set life color",  OFFSET( life_color_str), AV_OPT_TYPE_STRING, {.str="white"}, CHAR_MIN, CHAR_MAX },
 -     { "death_color", "set death color", OFFSET(death_color_str), AV_OPT_TYPE_STRING, {.str="black"}, CHAR_MIN, CHAR_MAX },
 -     { "mold_color",  "set mold color",  OFFSET( mold_color_str), AV_OPT_TYPE_STRING, {.str="black"}, CHAR_MIN, CHAR_MAX },
 -     { 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 rule as a number, expressed in the form STAY|(BORN<<9),
 -          * where STAY and BORN 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] == ALIVE_CELL ? '@' : ' ';
 -         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;
 -     av_freep(&life->filename);
 - 
 -     /* 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++)) ? ALIVE_CELL : 0;
 -         }
 -     }
 -     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);
 -     }
 -     av_freep(&life->rate);
 - 
 -     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;
 -     }
 -     av_freep(&life->size);
 - 
 -     if ((ret = parse_rule(&life->born_rule, &life->stay_rule, life->rule_str, ctx)) < 0)
 -         return ret;
 - 
 - #define PARSE_COLOR(name) do { \
 -     if ((ret = av_parse_color(life->name ## _color, life->name ## _color_str, -1, ctx))) { \
 -         av_log(ctx, AV_LOG_ERROR, "Invalid " #name " color '%s'\n", \
 -                life->name ## _color_str); \
 -         return ret; \
 -     } \
 -     av_freep(&life->name ## _color_str); \
 - } while (0)
 - 
 -     PARSE_COLOR(life);
 -     PARSE_COLOR(death);
 -     PARSE_COLOR(mold);
 - 
 -     if (!life->mold && memcmp(life->mold_color, "\x00\x00\x00", 3))
 -         av_log(ctx, AV_LOG_WARNING,
 -                "Mold color is set while mold isn't, ignoring the color.\n");
 - 
 -     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] = ALIVE_CELL;
 -         }
 -         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 seed:%u\n",
 -            life->w, life->h, frame_rate.num, frame_rate.den,
 -            life->rule_str, life->stay_rule, life->born_rule, life->stitch,
 -            life->random_seed);
 -     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;
 -     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, alive, cell;
 -             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]] == ALIVE_CELL) +
 -                 (pos[N ][0] == -1 || pos[N ][1] == -1 ? 0 : oldbuf[pos[N ][0]*life->w + pos[N ][1]] == ALIVE_CELL) +
 -                 (pos[NE][0] == -1 || pos[NE][1] == -1 ? 0 : oldbuf[pos[NE][0]*life->w + pos[NE][1]] == ALIVE_CELL) +
 -                 (pos[W ][0] == -1 || pos[W ][1] == -1 ? 0 : oldbuf[pos[W ][0]*life->w + pos[W ][1]] == ALIVE_CELL) +
 -                 (pos[E ][0] == -1 || pos[E ][1] == -1 ? 0 : oldbuf[pos[E ][0]*life->w + pos[E ][1]] == ALIVE_CELL) +
 -                 (pos[SW][0] == -1 || pos[SW][1] == -1 ? 0 : oldbuf[pos[SW][0]*life->w + pos[SW][1]] == ALIVE_CELL) +
 -                 (pos[S ][0] == -1 || pos[S ][1] == -1 ? 0 : oldbuf[pos[S ][0]*life->w + pos[S ][1]] == ALIVE_CELL) +
 -                 (pos[SE][0] == -1 || pos[SE][1] == -1 ? 0 : oldbuf[pos[SE][0]*life->w + pos[SE][1]] == ALIVE_CELL);
 -             cell  = oldbuf[i*life->w + j];
 -             alive = 1<<n & (cell == ALIVE_CELL ? life->stay_rule : life->born_rule);
 -             if (alive)     *newbuf = ALIVE_CELL; // new cell is alive
 -             else if (cell) *newbuf = cell - 1;   // new cell is dead and in the process of mold
 -             else           *newbuf = 0;          // new cell is definitely dead
 -             av_dlog(ctx, "i:%d j:%d live_neighbors:%d cell:%d -> cell:%d\n", i, j, n, cell, *newbuf);
 -             newbuf++;
 -         }
 -     }
 - 
 -     life->buf_idx = !life->buf_idx;
 - }
 - 
 - static void fill_picture_monoblack(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] == ALIVE_CELL)<<(7-k++);
 -             if (k==8 || j == life->w-1) {
 -                 k = 0;
 -                 *p++ = byte;
 -                 byte = 0;
 -             }
 -         }
 -     }
 - }
 - 
 - // divide by 255 and round to nearest
 - // apply a fast variant: (X+127)/255 = ((X+127)*257+257)>>16 = ((X+128)*257)>>16
 - #define FAST_DIV255(x) ((((x) + 128) * 257) >> 16)
 - 
 - static void fill_picture_rgb(AVFilterContext *ctx, AVFilterBufferRef *picref)
 - {
 -     LifeContext *life = ctx->priv;
 -     uint8_t *buf = life->buf[life->buf_idx];
 -     int i, j;
 - 
 -     /* fill the output picture with the old grid buffer */
 -     for (i = 0; i < life->h; i++) {
 -         uint8_t *p = picref->data[0] + i * picref->linesize[0];
 -         for (j = 0; j < life->w; j++) {
 -             uint8_t v = buf[i*life->w + j];
 -             if (life->mold && v != ALIVE_CELL) {
 -                 const uint8_t *c1 = life-> mold_color;
 -                 const uint8_t *c2 = life->death_color;
 -                 int death_age = FFMIN((0xff - v) * life->mold, 0xff);
 -                 *p++ = FAST_DIV255((c2[0] << 8) + ((int)c1[0] - (int)c2[0]) * death_age);
 -                 *p++ = FAST_DIV255((c2[1] << 8) + ((int)c1[1] - (int)c2[1]) * death_age);
 -                 *p++ = FAST_DIV255((c2[2] << 8) + ((int)c1[2] - (int)c2[2]) * death_age);
 -             } else {
 -                 const uint8_t *c = v == ALIVE_CELL ? life->life_color : life->death_color;
 -                 AV_WB24(p, c[0]<<16 | c[1]<<8 | c[2]);
 -                 p += 3;
 -             }
 -         }
 -     }
 - }
 - 
 - 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;
 - 
 -     life->draw(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)
 - {
 -     LifeContext *life = ctx->priv;
 -     enum PixelFormat pix_fmts[] = { PIX_FMT_NONE, PIX_FMT_NONE };
 -     if (life->mold || memcmp(life-> life_color, "\xff\xff\xff", 3)
 -                    || memcmp(life->death_color, "\x00\x00\x00", 3)) {
 -         pix_fmts[0] = PIX_FMT_RGB24;
 -         life->draw = fill_picture_rgb;
 -     } else {
 -         pix_fmts[0] = PIX_FMT_MONOBLACK;
 -         life->draw = fill_picture_monoblack;
 -     }
 -     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}
 -     },
 - };
 
 
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