2 * Copyright (c) Stefano Sabatini 2010
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 * life video source, based on John Conways' Life Game
28 #include "libavutil/file.h"
29 #include "libavutil/intreadwrite.h"
30 #include "libavutil/lfg.h"
31 #include "libavutil/opt.h"
32 #include "libavutil/parseutils.h"
33 #include "libavutil/random_seed.h"
45 * The two grid state buffers.
47 * A 0xFF (ALIVE_CELL) value means the cell is alive (or new born), while
48 * the decreasing values from 0xFE to 0 means the cell is dead; the range
49 * of values is used for the slow death effect, or mold (0xFE means dead,
50 * 0xFD means very dead, 0xFC means very very dead... and 0x00 means
51 * definitely dead/mold).
56 uint16_t stay_rule; ///< encode the behavior for filled cells
57 uint16_t born_rule; ///< encode the behavior for empty cells
60 char *size; ///< video frame size
61 char *rate; ///< video frame rate
62 double random_fill_ratio;
67 char *death_color_str;
69 uint8_t life_color[4];
70 uint8_t death_color[4];
71 uint8_t mold_color[4];
73 void (*draw)(AVFilterContext*, AVFilterBufferRef*);
76 #define ALIVE_CELL 0xFF
77 #define OFFSET(x) offsetof(LifeContext, x)
79 static const AVOption life_options[] = {
80 { "filename", "set source file", OFFSET(filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0 },
81 { "f", "set source file", OFFSET(filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0 },
82 { "size", "set video size", OFFSET(size), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0 },
83 { "s", "set video size", OFFSET(size), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0 },
84 { "rate", "set video rate", OFFSET(rate), AV_OPT_TYPE_STRING, {.str = "25"}, 0, 0 },
85 { "r", "set video rate", OFFSET(rate), AV_OPT_TYPE_STRING, {.str = "25"}, 0, 0 },
86 { "rule", "set rule", OFFSET(rule_str), AV_OPT_TYPE_STRING, {.str = "B3/S23"}, CHAR_MIN, CHAR_MAX },
87 { "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 },
88 { "ratio", "set fill ratio for filling initial grid randomly", OFFSET(random_fill_ratio), AV_OPT_TYPE_DOUBLE, {.dbl=1/M_PHI}, 0, 1 },
89 { "random_seed", "set the seed for filling the initial grid randomly", OFFSET(random_seed), AV_OPT_TYPE_INT, {.dbl=-1}, -1, UINT32_MAX },
90 { "seed", "set the seed for filling the initial grid randomly", OFFSET(random_seed), AV_OPT_TYPE_INT, {.dbl=-1}, -1, UINT32_MAX },
91 { "stitch", "stitch boundaries", OFFSET(stitch), AV_OPT_TYPE_INT, {.dbl=1}, 0, 1 },
92 { "mold", "set mold speed for dead cells", OFFSET(mold), AV_OPT_TYPE_INT, {.dbl=0}, 0, 0xFF },
93 { "life_color", "set life color", OFFSET( life_color_str), AV_OPT_TYPE_STRING, {.str="white"}, CHAR_MIN, CHAR_MAX },
94 { "death_color", "set death color", OFFSET(death_color_str), AV_OPT_TYPE_STRING, {.str="black"}, CHAR_MIN, CHAR_MAX },
95 { "mold_color", "set mold color", OFFSET( mold_color_str), AV_OPT_TYPE_STRING, {.str="black"}, CHAR_MIN, CHAR_MAX },
99 static const char *life_get_name(void *ctx)
104 static const AVClass life_class = {
110 static int parse_rule(uint16_t *born_rule, uint16_t *stay_rule,
111 const char *rule_str, void *log_ctx)
114 const char *p = rule_str;
118 if (strchr("bBsS", *p)) {
119 /* parse rule as a Born / Stay Alive code, see
120 * http://en.wikipedia.org/wiki/Conway%27s_Game_of_Life */
122 uint16_t *rule = (*p == 'b' || *p == 'B') ? born_rule : stay_rule;
124 while (*p >= '0' && *p <= '8') {
125 *rule += 1<<(*p - '0');
131 } while (strchr("bBsS", *p));
136 /* parse rule as a number, expressed in the form STAY|(BORN<<9),
137 * where STAY and BORN encode the corresponding 9-bits rule */
138 long int rule = strtol(rule_str, &tail, 10);
141 *born_rule = ((1<<9)-1) & rule;
142 *stay_rule = rule >> 9;
148 av_log(log_ctx, AV_LOG_ERROR, "Invalid rule code '%s' provided\n", rule_str);
149 return AVERROR(EINVAL);
153 static void show_life_grid(AVFilterContext *ctx)
155 LifeContext *life = ctx->priv;
158 char *line = av_malloc(life->w + 1);
161 for (i = 0; i < life->h; i++) {
162 for (j = 0; j < life->w; j++)
163 line[j] = life->buf[life->buf_idx][i*life->w + j] == ALIVE_CELL ? '@' : ' ';
165 av_log(ctx, AV_LOG_DEBUG, "%3d: %s\n", i, line);
171 static int init_pattern_from_file(AVFilterContext *ctx)
173 LifeContext *life = ctx->priv;
175 int ret, i, i0, j, h = 0, w, max_w = 0;
177 if ((ret = av_file_map(life->filename, &life->file_buf, &life->file_bufsize,
181 /* prescan file to get the number of lines and the maximum width */
183 for (i = 0; i < life->file_bufsize; i++) {
184 if (life->file_buf[i] == '\n') {
185 h++; max_w = FFMAX(w, max_w); w = 0;
190 av_log(ctx, AV_LOG_DEBUG, "h:%d max_w:%d\n", h, max_w);
193 if (max_w > life->w || h > life->h) {
194 av_log(ctx, AV_LOG_ERROR,
195 "The specified size is %dx%d which cannot contain the provided file size of %dx%d\n",
196 life->w, life->h, max_w, h);
197 return AVERROR(EINVAL);
200 /* size was not specified, set it to size of the grid */
205 if (!(life->buf[0] = av_mallocz(sizeof(char) * life->h * life->w)) ||
206 !(life->buf[1] = av_mallocz(sizeof(char) * life->h * life->w))) {
207 av_free(life->buf[0]);
208 av_free(life->buf[1]);
209 return AVERROR(ENOMEM);
214 for (i0 = 0, i = (life->h - h)/2; i0 < h; i0++, i++) {
215 for (j = (life->w - max_w)/2;; j++) {
216 av_log(ctx, AV_LOG_DEBUG, "%d:%d %c\n", i, j, *p == '\n' ? 'N' : *p);
220 life->buf[0][i*life->w + j] = isgraph(*(p++)) ? ALIVE_CELL : 0;
228 static int init(AVFilterContext *ctx, const char *args, void *opaque)
230 LifeContext *life = ctx->priv;
231 AVRational frame_rate;
234 life->class = &life_class;
235 av_opt_set_defaults(life);
237 if ((ret = av_set_options_string(life, args, "=", ":")) < 0) {
238 av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
242 if ((ret = av_parse_video_rate(&frame_rate, life->rate)) < 0) {
243 av_log(ctx, AV_LOG_ERROR, "Invalid frame rate: %s\n", life->rate);
244 return AVERROR(EINVAL);
247 if (!life->size && !life->filename)
248 av_opt_set(life, "size", "320x240", 0);
251 (ret = av_parse_video_size(&life->w, &life->h, life->size)) < 0) {
252 av_log(ctx, AV_LOG_ERROR, "Invalid frame size: %s\n", life->size);
256 if ((ret = parse_rule(&life->born_rule, &life->stay_rule, life->rule_str, ctx)) < 0)
259 #define PARSE_COLOR(name) do { \
260 if ((ret = av_parse_color(life->name ## _color, life->name ## _color_str, -1, ctx))) { \
261 av_log(ctx, AV_LOG_ERROR, "Invalid " #name " color '%s'\n", \
262 life->name ## _color_str); \
271 if (!life->mold && memcmp(life->mold_color, "\x00\x00\x00", 3))
272 av_log(ctx, AV_LOG_WARNING,
273 "Mold color is set while mold isn't, ignoring the color.\n");
275 life->time_base.num = frame_rate.den;
276 life->time_base.den = frame_rate.num;
278 if (!life->filename) {
279 /* fill the grid randomly */
282 if (!(life->buf[0] = av_mallocz(sizeof(char) * life->h * life->w)) ||
283 !(life->buf[1] = av_mallocz(sizeof(char) * life->h * life->w))) {
284 av_free(life->buf[0]);
285 av_free(life->buf[1]);
286 return AVERROR(ENOMEM);
288 if (life->random_seed == -1)
289 life->random_seed = av_get_random_seed();
291 av_lfg_init(&life->lfg, life->random_seed);
293 for (i = 0; i < life->w * life->h; i++) {
294 double r = (double)av_lfg_get(&life->lfg) / UINT32_MAX;
295 if (r <= life->random_fill_ratio)
296 life->buf[0][i] = ALIVE_CELL;
300 if ((ret = init_pattern_from_file(ctx)) < 0)
304 av_log(ctx, AV_LOG_INFO,
305 "s:%dx%d r:%d/%d rule:%s stay_rule:%d born_rule:%d stitch:%d seed:%u\n",
306 life->w, life->h, frame_rate.num, frame_rate.den,
307 life->rule_str, life->stay_rule, life->born_rule, life->stitch,
312 static av_cold void uninit(AVFilterContext *ctx)
314 LifeContext *life = ctx->priv;
316 av_file_unmap(life->file_buf, life->file_bufsize);
317 av_freep(&life->rule_str);
318 av_freep(&life->buf[0]);
319 av_freep(&life->buf[1]);
322 static int config_props(AVFilterLink *outlink)
324 LifeContext *life = outlink->src->priv;
326 outlink->w = life->w;
327 outlink->h = life->h;
328 outlink->time_base = life->time_base;
333 static void evolve(AVFilterContext *ctx)
335 LifeContext *life = ctx->priv;
337 uint8_t *oldbuf = life->buf[ life->buf_idx];
338 uint8_t *newbuf = life->buf[!life->buf_idx];
340 enum { NW, N, NE, W, E, SW, S, SE };
342 /* evolve the grid */
343 for (i = 0; i < life->h; i++) {
344 for (j = 0; j < life->w; j++) {
345 int pos[8][2], n, alive, cell;
347 pos[NW][0] = (i-1) < 0 ? life->h-1 : i-1; pos[NW][1] = (j-1) < 0 ? life->w-1 : j-1;
348 pos[N ][0] = (i-1) < 0 ? life->h-1 : i-1; pos[N ][1] = j ;
349 pos[NE][0] = (i-1) < 0 ? life->h-1 : i-1; pos[NE][1] = (j+1) == life->w ? 0 : j+1;
350 pos[W ][0] = i ; pos[W ][1] = (j-1) < 0 ? life->w-1 : j-1;
351 pos[E ][0] = i ; pos[E ][1] = (j+1) == life->w ? 0 : j+1;
352 pos[SW][0] = (i+1) == life->h ? 0 : i+1; pos[SW][1] = (j-1) < 0 ? life->w-1 : j-1;
353 pos[S ][0] = (i+1) == life->h ? 0 : i+1; pos[S ][1] = j ;
354 pos[SE][0] = (i+1) == life->h ? 0 : i+1; pos[SE][1] = (j+1) == life->w ? 0 : j+1;
356 pos[NW][0] = (i-1) < 0 ? -1 : i-1; pos[NW][1] = (j-1) < 0 ? -1 : j-1;
357 pos[N ][0] = (i-1) < 0 ? -1 : i-1; pos[N ][1] = j ;
358 pos[NE][0] = (i-1) < 0 ? -1 : i-1; pos[NE][1] = (j+1) == life->w ? -1 : j+1;
359 pos[W ][0] = i ; pos[W ][1] = (j-1) < 0 ? -1 : j-1;
360 pos[E ][0] = i ; pos[E ][1] = (j+1) == life->w ? -1 : j+1;
361 pos[SW][0] = (i+1) == life->h ? -1 : i+1; pos[SW][1] = (j-1) < 0 ? -1 : j-1;
362 pos[S ][0] = (i+1) == life->h ? -1 : i+1; pos[S ][1] = j ;
363 pos[SE][0] = (i+1) == life->h ? -1 : i+1; pos[SE][1] = (j+1) == life->w ? -1 : j+1;
366 /* compute the number of live neighbor cells */
367 n = (pos[NW][0] == -1 || pos[NW][1] == -1 ? 0 : oldbuf[pos[NW][0]*life->w + pos[NW][1]] == ALIVE_CELL) +
368 (pos[N ][0] == -1 || pos[N ][1] == -1 ? 0 : oldbuf[pos[N ][0]*life->w + pos[N ][1]] == ALIVE_CELL) +
369 (pos[NE][0] == -1 || pos[NE][1] == -1 ? 0 : oldbuf[pos[NE][0]*life->w + pos[NE][1]] == ALIVE_CELL) +
370 (pos[W ][0] == -1 || pos[W ][1] == -1 ? 0 : oldbuf[pos[W ][0]*life->w + pos[W ][1]] == ALIVE_CELL) +
371 (pos[E ][0] == -1 || pos[E ][1] == -1 ? 0 : oldbuf[pos[E ][0]*life->w + pos[E ][1]] == ALIVE_CELL) +
372 (pos[SW][0] == -1 || pos[SW][1] == -1 ? 0 : oldbuf[pos[SW][0]*life->w + pos[SW][1]] == ALIVE_CELL) +
373 (pos[S ][0] == -1 || pos[S ][1] == -1 ? 0 : oldbuf[pos[S ][0]*life->w + pos[S ][1]] == ALIVE_CELL) +
374 (pos[SE][0] == -1 || pos[SE][1] == -1 ? 0 : oldbuf[pos[SE][0]*life->w + pos[SE][1]] == ALIVE_CELL);
375 cell = oldbuf[i*life->w + j];
376 alive = 1<<n & (cell == ALIVE_CELL ? life->stay_rule : life->born_rule);
377 if (alive) *newbuf = ALIVE_CELL; // new cell is alive
378 else if (cell) *newbuf = cell - 1; // new cell is dead and in the process of mold
379 else *newbuf = 0; // new cell is definitely dead
380 av_dlog(ctx, "i:%d j:%d live_neighbors:%d cell:%d -> cell:%d\n", i, j, n, cell, *newbuf);
385 life->buf_idx = !life->buf_idx;
388 static void fill_picture_monoblack(AVFilterContext *ctx, AVFilterBufferRef *picref)
390 LifeContext *life = ctx->priv;
391 uint8_t *buf = life->buf[life->buf_idx];
394 /* fill the output picture with the old grid buffer */
395 for (i = 0; i < life->h; i++) {
397 uint8_t *p = picref->data[0] + i * picref->linesize[0];
398 for (k = 0, j = 0; j < life->w; j++) {
399 byte |= (buf[i*life->w+j] == ALIVE_CELL)<<(7-k++);
400 if (k==8 || j == life->w-1) {
409 // divide by 255 and round to nearest
410 // apply a fast variant: (X+127)/255 = ((X+127)*257+257)>>16 = ((X+128)*257)>>16
411 #define FAST_DIV255(x) ((((x) + 128) * 257) >> 16)
413 static void fill_picture_rgb(AVFilterContext *ctx, AVFilterBufferRef *picref)
415 LifeContext *life = ctx->priv;
416 uint8_t *buf = life->buf[life->buf_idx];
419 /* fill the output picture with the old grid buffer */
420 for (i = 0; i < life->h; i++) {
421 uint8_t *p = picref->data[0] + i * picref->linesize[0];
422 for (j = 0; j < life->w; j++) {
423 uint8_t v = buf[i*life->w + j];
424 if (life->mold && v != ALIVE_CELL) {
425 const uint8_t *c1 = life-> mold_color;
426 const uint8_t *c2 = life->death_color;
427 int death_age = FFMIN((0xff - v) * life->mold, 0xff);
428 *p++ = FAST_DIV255((c2[0] << 8) + ((int)c1[0] - (int)c2[0]) * death_age);
429 *p++ = FAST_DIV255((c2[1] << 8) + ((int)c1[1] - (int)c2[1]) * death_age);
430 *p++ = FAST_DIV255((c2[2] << 8) + ((int)c1[2] - (int)c2[2]) * death_age);
432 const uint8_t *c = v == ALIVE_CELL ? life->life_color : life->death_color;
433 AV_WB24(p, c[0]<<16 | c[1]<<8 | c[2]);
440 static int request_frame(AVFilterLink *outlink)
442 LifeContext *life = outlink->src->priv;
443 AVFilterBufferRef *picref = avfilter_get_video_buffer(outlink, AV_PERM_WRITE, life->w, life->h);
444 picref->video->sample_aspect_ratio = (AVRational) {1, 1};
445 picref->pts = life->pts++;
448 life->draw(outlink->src, picref);
449 evolve(outlink->src);
451 show_life_grid(outlink->src);
454 avfilter_start_frame(outlink, avfilter_ref_buffer(picref, ~0));
455 avfilter_draw_slice(outlink, 0, life->h, 1);
456 avfilter_end_frame(outlink);
457 avfilter_unref_buffer(picref);
462 static int query_formats(AVFilterContext *ctx)
464 LifeContext *life = ctx->priv;
465 enum PixelFormat pix_fmts[] = { PIX_FMT_NONE, PIX_FMT_NONE };
466 if (life->mold || memcmp(life-> life_color, "\xff\xff\xff", 3)
467 || memcmp(life->death_color, "\x00\x00\x00", 3)) {
468 pix_fmts[0] = PIX_FMT_RGB24;
469 life->draw = fill_picture_rgb;
471 pix_fmts[0] = PIX_FMT_MONOBLACK;
472 life->draw = fill_picture_monoblack;
474 avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
478 AVFilter avfilter_vsrc_life = {
480 .description = NULL_IF_CONFIG_SMALL("Create life."),
481 .priv_size = sizeof(LifeContext),
484 .query_formats = query_formats,
486 .inputs = (const AVFilterPad[]) {
489 .outputs = (const AVFilterPad[]) {
491 .type = AVMEDIA_TYPE_VIDEO,
492 .request_frame = request_frame,
493 .config_props = config_props },