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"
47 * The two grid state buffers.
49 * A 0xFF (ALIVE_CELL) value means the cell is alive (or new born), while
50 * the decreasing values from 0xFE to 0 means the cell is dead; the range
51 * of values is used for the slow death effect, or mold (0xFE means dead,
52 * 0xFD means very dead, 0xFC means very very dead... and 0x00 means
53 * definitely dead/mold).
58 uint16_t stay_rule; ///< encode the behavior for filled cells
59 uint16_t born_rule; ///< encode the behavior for empty cells
62 char *rate; ///< video frame rate
63 double random_fill_ratio;
68 char *death_color_str;
70 uint8_t life_color[4];
71 uint8_t death_color[4];
72 uint8_t mold_color[4];
74 void (*draw)(AVFilterContext*, AVFilterBufferRef*);
77 #define ALIVE_CELL 0xFF
78 #define OFFSET(x) offsetof(LifeContext, x)
80 static const AVOption life_options[] = {
81 { "filename", "set source file", OFFSET(filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0 },
82 { "f", "set source file", OFFSET(filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0 },
83 { "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0 },
84 { "s", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0 },
85 { "rate", "set video rate", OFFSET(rate), AV_OPT_TYPE_STRING, {.str = "25"}, 0, 0 },
86 { "r", "set video rate", OFFSET(rate), AV_OPT_TYPE_STRING, {.str = "25"}, 0, 0 },
87 { "rule", "set rule", OFFSET(rule_str), AV_OPT_TYPE_STRING, {.str = "B3/S23"}, CHAR_MIN, CHAR_MAX },
88 { "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 },
89 { "ratio", "set fill ratio for filling initial grid randomly", OFFSET(random_fill_ratio), AV_OPT_TYPE_DOUBLE, {.dbl=1/M_PHI}, 0, 1 },
90 { "random_seed", "set the seed for filling the initial grid randomly", OFFSET(random_seed), AV_OPT_TYPE_INT, {.dbl=-1}, -1, UINT32_MAX },
91 { "seed", "set the seed for filling the initial grid randomly", OFFSET(random_seed), AV_OPT_TYPE_INT, {.dbl=-1}, -1, UINT32_MAX },
92 { "stitch", "stitch boundaries", OFFSET(stitch), AV_OPT_TYPE_INT, {.dbl=1}, 0, 1 },
93 { "mold", "set mold speed for dead cells", OFFSET(mold), AV_OPT_TYPE_INT, {.dbl=0}, 0, 0xFF },
94 { "life_color", "set life color", OFFSET( life_color_str), AV_OPT_TYPE_STRING, {.str="white"}, CHAR_MIN, CHAR_MAX },
95 { "death_color", "set death color", OFFSET(death_color_str), AV_OPT_TYPE_STRING, {.str="black"}, CHAR_MIN, CHAR_MAX },
96 { "mold_color", "set mold color", OFFSET( mold_color_str), AV_OPT_TYPE_STRING, {.str="black"}, CHAR_MIN, CHAR_MAX },
100 static const AVClass life_class = {
101 .class_name = "life",
102 .item_name = av_default_item_name,
103 .option = life_options,
104 .version = LIBAVUTIL_VERSION_INT,
105 .category = AV_CLASS_CATEGORY_FILTER,
108 static int parse_rule(uint16_t *born_rule, uint16_t *stay_rule,
109 const char *rule_str, void *log_ctx)
112 const char *p = rule_str;
116 if (strchr("bBsS", *p)) {
117 /* parse rule as a Born / Stay Alive code, see
118 * http://en.wikipedia.org/wiki/Conway%27s_Game_of_Life */
120 uint16_t *rule = (*p == 'b' || *p == 'B') ? born_rule : stay_rule;
122 while (*p >= '0' && *p <= '8') {
123 *rule += 1<<(*p - '0');
129 } while (strchr("bBsS", *p));
134 /* parse rule as a number, expressed in the form STAY|(BORN<<9),
135 * where STAY and BORN encode the corresponding 9-bits rule */
136 long int rule = strtol(rule_str, &tail, 10);
139 *born_rule = ((1<<9)-1) & rule;
140 *stay_rule = rule >> 9;
146 av_log(log_ctx, AV_LOG_ERROR, "Invalid rule code '%s' provided\n", rule_str);
147 return AVERROR(EINVAL);
151 static void show_life_grid(AVFilterContext *ctx)
153 LifeContext *life = ctx->priv;
156 char *line = av_malloc(life->w + 1);
159 for (i = 0; i < life->h; i++) {
160 for (j = 0; j < life->w; j++)
161 line[j] = life->buf[life->buf_idx][i*life->w + j] == ALIVE_CELL ? '@' : ' ';
163 av_log(ctx, AV_LOG_DEBUG, "%3d: %s\n", i, line);
169 static int init_pattern_from_file(AVFilterContext *ctx)
171 LifeContext *life = ctx->priv;
173 int ret, i, i0, j, h = 0, w, max_w = 0;
175 if ((ret = av_file_map(life->filename, &life->file_buf, &life->file_bufsize,
178 av_freep(&life->filename);
180 /* prescan file to get the number of lines and the maximum width */
182 for (i = 0; i < life->file_bufsize; i++) {
183 if (life->file_buf[i] == '\n') {
184 h++; max_w = FFMAX(w, max_w); w = 0;
189 av_log(ctx, AV_LOG_DEBUG, "h:%d max_w:%d\n", h, max_w);
192 if (max_w > life->w || h > life->h) {
193 av_log(ctx, AV_LOG_ERROR,
194 "The specified size is %dx%d which cannot contain the provided file size of %dx%d\n",
195 life->w, life->h, max_w, h);
196 return AVERROR(EINVAL);
199 /* size was not specified, set it to size of the grid */
204 if (!(life->buf[0] = av_mallocz(sizeof(char) * life->h * life->w)) ||
205 !(life->buf[1] = av_mallocz(sizeof(char) * life->h * life->w))) {
206 av_free(life->buf[0]);
207 av_free(life->buf[1]);
208 return AVERROR(ENOMEM);
213 for (i0 = 0, i = (life->h - h)/2; i0 < h; i0++, i++) {
214 for (j = (life->w - max_w)/2;; j++) {
215 av_log(ctx, AV_LOG_DEBUG, "%d:%d %c\n", i, j, *p == '\n' ? 'N' : *p);
219 life->buf[0][i*life->w + j] = isgraph(*(p++)) ? ALIVE_CELL : 0;
227 static int init(AVFilterContext *ctx, const char *args, void *opaque)
229 LifeContext *life = ctx->priv;
230 AVRational frame_rate;
233 life->class = &life_class;
234 av_opt_set_defaults(life);
236 if ((ret = av_set_options_string(life, args, "=", ":")) < 0) {
237 av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
241 if ((ret = av_parse_video_rate(&frame_rate, life->rate)) < 0) {
242 av_log(ctx, AV_LOG_ERROR, "Invalid frame rate: %s\n", life->rate);
243 return AVERROR(EINVAL);
245 av_freep(&life->rate);
247 if (!life->w && !life->filename)
248 av_opt_set(life, "size", "320x240", 0);
250 if ((ret = parse_rule(&life->born_rule, &life->stay_rule, life->rule_str, ctx)) < 0)
253 #define PARSE_COLOR(name) do { \
254 if ((ret = av_parse_color(life->name ## _color, life->name ## _color_str, -1, ctx))) { \
255 av_log(ctx, AV_LOG_ERROR, "Invalid " #name " color '%s'\n", \
256 life->name ## _color_str); \
259 av_freep(&life->name ## _color_str); \
266 if (!life->mold && memcmp(life->mold_color, "\x00\x00\x00", 3))
267 av_log(ctx, AV_LOG_WARNING,
268 "Mold color is set while mold isn't, ignoring the color.\n");
270 life->time_base.num = frame_rate.den;
271 life->time_base.den = frame_rate.num;
273 if (!life->filename) {
274 /* fill the grid randomly */
277 if (!(life->buf[0] = av_mallocz(sizeof(char) * life->h * life->w)) ||
278 !(life->buf[1] = av_mallocz(sizeof(char) * life->h * life->w))) {
279 av_free(life->buf[0]);
280 av_free(life->buf[1]);
281 return AVERROR(ENOMEM);
283 if (life->random_seed == -1)
284 life->random_seed = av_get_random_seed();
286 av_lfg_init(&life->lfg, life->random_seed);
288 for (i = 0; i < life->w * life->h; i++) {
289 double r = (double)av_lfg_get(&life->lfg) / UINT32_MAX;
290 if (r <= life->random_fill_ratio)
291 life->buf[0][i] = ALIVE_CELL;
295 if ((ret = init_pattern_from_file(ctx)) < 0)
299 av_log(ctx, AV_LOG_INFO,
300 "s:%dx%d r:%d/%d rule:%s stay_rule:%d born_rule:%d stitch:%d seed:%u\n",
301 life->w, life->h, frame_rate.num, frame_rate.den,
302 life->rule_str, life->stay_rule, life->born_rule, life->stitch,
307 static av_cold void uninit(AVFilterContext *ctx)
309 LifeContext *life = ctx->priv;
311 av_file_unmap(life->file_buf, life->file_bufsize);
312 av_freep(&life->rule_str);
313 av_freep(&life->buf[0]);
314 av_freep(&life->buf[1]);
317 static int config_props(AVFilterLink *outlink)
319 LifeContext *life = outlink->src->priv;
321 outlink->w = life->w;
322 outlink->h = life->h;
323 outlink->time_base = life->time_base;
328 static void evolve(AVFilterContext *ctx)
330 LifeContext *life = ctx->priv;
332 uint8_t *oldbuf = life->buf[ life->buf_idx];
333 uint8_t *newbuf = life->buf[!life->buf_idx];
335 enum { NW, N, NE, W, E, SW, S, SE };
337 /* evolve the grid */
338 for (i = 0; i < life->h; i++) {
339 for (j = 0; j < life->w; j++) {
340 int pos[8][2], n, alive, cell;
342 pos[NW][0] = (i-1) < 0 ? life->h-1 : i-1; pos[NW][1] = (j-1) < 0 ? life->w-1 : j-1;
343 pos[N ][0] = (i-1) < 0 ? life->h-1 : i-1; pos[N ][1] = j ;
344 pos[NE][0] = (i-1) < 0 ? life->h-1 : i-1; pos[NE][1] = (j+1) == life->w ? 0 : j+1;
345 pos[W ][0] = i ; pos[W ][1] = (j-1) < 0 ? life->w-1 : j-1;
346 pos[E ][0] = i ; pos[E ][1] = (j+1) == life->w ? 0 : j+1;
347 pos[SW][0] = (i+1) == life->h ? 0 : i+1; pos[SW][1] = (j-1) < 0 ? life->w-1 : j-1;
348 pos[S ][0] = (i+1) == life->h ? 0 : i+1; pos[S ][1] = j ;
349 pos[SE][0] = (i+1) == life->h ? 0 : i+1; pos[SE][1] = (j+1) == life->w ? 0 : j+1;
351 pos[NW][0] = (i-1) < 0 ? -1 : i-1; pos[NW][1] = (j-1) < 0 ? -1 : j-1;
352 pos[N ][0] = (i-1) < 0 ? -1 : i-1; pos[N ][1] = j ;
353 pos[NE][0] = (i-1) < 0 ? -1 : i-1; pos[NE][1] = (j+1) == life->w ? -1 : j+1;
354 pos[W ][0] = i ; pos[W ][1] = (j-1) < 0 ? -1 : j-1;
355 pos[E ][0] = i ; pos[E ][1] = (j+1) == life->w ? -1 : j+1;
356 pos[SW][0] = (i+1) == life->h ? -1 : i+1; pos[SW][1] = (j-1) < 0 ? -1 : j-1;
357 pos[S ][0] = (i+1) == life->h ? -1 : i+1; pos[S ][1] = j ;
358 pos[SE][0] = (i+1) == life->h ? -1 : i+1; pos[SE][1] = (j+1) == life->w ? -1 : j+1;
361 /* compute the number of live neighbor cells */
362 n = (pos[NW][0] == -1 || pos[NW][1] == -1 ? 0 : oldbuf[pos[NW][0]*life->w + pos[NW][1]] == ALIVE_CELL) +
363 (pos[N ][0] == -1 || pos[N ][1] == -1 ? 0 : oldbuf[pos[N ][0]*life->w + pos[N ][1]] == ALIVE_CELL) +
364 (pos[NE][0] == -1 || pos[NE][1] == -1 ? 0 : oldbuf[pos[NE][0]*life->w + pos[NE][1]] == ALIVE_CELL) +
365 (pos[W ][0] == -1 || pos[W ][1] == -1 ? 0 : oldbuf[pos[W ][0]*life->w + pos[W ][1]] == ALIVE_CELL) +
366 (pos[E ][0] == -1 || pos[E ][1] == -1 ? 0 : oldbuf[pos[E ][0]*life->w + pos[E ][1]] == ALIVE_CELL) +
367 (pos[SW][0] == -1 || pos[SW][1] == -1 ? 0 : oldbuf[pos[SW][0]*life->w + pos[SW][1]] == ALIVE_CELL) +
368 (pos[S ][0] == -1 || pos[S ][1] == -1 ? 0 : oldbuf[pos[S ][0]*life->w + pos[S ][1]] == ALIVE_CELL) +
369 (pos[SE][0] == -1 || pos[SE][1] == -1 ? 0 : oldbuf[pos[SE][0]*life->w + pos[SE][1]] == ALIVE_CELL);
370 cell = oldbuf[i*life->w + j];
371 alive = 1<<n & (cell == ALIVE_CELL ? life->stay_rule : life->born_rule);
372 if (alive) *newbuf = ALIVE_CELL; // new cell is alive
373 else if (cell) *newbuf = cell - 1; // new cell is dead and in the process of mold
374 else *newbuf = 0; // new cell is definitely dead
375 av_dlog(ctx, "i:%d j:%d live_neighbors:%d cell:%d -> cell:%d\n", i, j, n, cell, *newbuf);
380 life->buf_idx = !life->buf_idx;
383 static void fill_picture_monoblack(AVFilterContext *ctx, AVFilterBufferRef *picref)
385 LifeContext *life = ctx->priv;
386 uint8_t *buf = life->buf[life->buf_idx];
389 /* fill the output picture with the old grid buffer */
390 for (i = 0; i < life->h; i++) {
392 uint8_t *p = picref->data[0] + i * picref->linesize[0];
393 for (k = 0, j = 0; j < life->w; j++) {
394 byte |= (buf[i*life->w+j] == ALIVE_CELL)<<(7-k++);
395 if (k==8 || j == life->w-1) {
404 // divide by 255 and round to nearest
405 // apply a fast variant: (X+127)/255 = ((X+127)*257+257)>>16 = ((X+128)*257)>>16
406 #define FAST_DIV255(x) ((((x) + 128) * 257) >> 16)
408 static void fill_picture_rgb(AVFilterContext *ctx, AVFilterBufferRef *picref)
410 LifeContext *life = ctx->priv;
411 uint8_t *buf = life->buf[life->buf_idx];
414 /* fill the output picture with the old grid buffer */
415 for (i = 0; i < life->h; i++) {
416 uint8_t *p = picref->data[0] + i * picref->linesize[0];
417 for (j = 0; j < life->w; j++) {
418 uint8_t v = buf[i*life->w + j];
419 if (life->mold && v != ALIVE_CELL) {
420 const uint8_t *c1 = life-> mold_color;
421 const uint8_t *c2 = life->death_color;
422 int death_age = FFMIN((0xff - v) * life->mold, 0xff);
423 *p++ = FAST_DIV255((c2[0] << 8) + ((int)c1[0] - (int)c2[0]) * death_age);
424 *p++ = FAST_DIV255((c2[1] << 8) + ((int)c1[1] - (int)c2[1]) * death_age);
425 *p++ = FAST_DIV255((c2[2] << 8) + ((int)c1[2] - (int)c2[2]) * death_age);
427 const uint8_t *c = v == ALIVE_CELL ? life->life_color : life->death_color;
428 AV_WB24(p, c[0]<<16 | c[1]<<8 | c[2]);
435 static int request_frame(AVFilterLink *outlink)
437 LifeContext *life = outlink->src->priv;
438 AVFilterBufferRef *picref = ff_get_video_buffer(outlink, AV_PERM_WRITE, life->w, life->h);
439 picref->video->sample_aspect_ratio = (AVRational) {1, 1};
440 picref->pts = life->pts++;
443 life->draw(outlink->src, picref);
444 evolve(outlink->src);
446 show_life_grid(outlink->src);
449 ff_start_frame(outlink, avfilter_ref_buffer(picref, ~0));
450 ff_draw_slice(outlink, 0, life->h, 1);
451 ff_end_frame(outlink);
452 avfilter_unref_buffer(picref);
457 static int query_formats(AVFilterContext *ctx)
459 LifeContext *life = ctx->priv;
460 enum PixelFormat pix_fmts[] = { PIX_FMT_NONE, PIX_FMT_NONE };
461 if (life->mold || memcmp(life-> life_color, "\xff\xff\xff", 3)
462 || memcmp(life->death_color, "\x00\x00\x00", 3)) {
463 pix_fmts[0] = PIX_FMT_RGB24;
464 life->draw = fill_picture_rgb;
466 pix_fmts[0] = PIX_FMT_MONOBLACK;
467 life->draw = fill_picture_monoblack;
469 ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
473 AVFilter avfilter_vsrc_life = {
475 .description = NULL_IF_CONFIG_SMALL("Create life."),
476 .priv_size = sizeof(LifeContext),
479 .query_formats = query_formats,
481 .inputs = (const AVFilterPad[]) {
484 .outputs = (const AVFilterPad[]) {
486 .type = AVMEDIA_TYPE_VIDEO,
487 .request_frame = request_frame,
488 .config_props = config_props },