|
- /*
- * 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 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] ? '@' : ' ';
- 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}
- },
- };
|