/*
* 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/internal.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/lfg.h"
#include "libavutil/opt.h"
#include "libavutil/parseutils.h"
#include "libavutil/random_seed.h"
#include "libavutil/avstring.h"
#include "avfilter.h"
#include "internal.h"
#include "formats.h"
#include "video.h"
typedef struct LifeContext {
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 frame_rate;
double random_fill_ratio;
uint32_t random_seed;
int stitch;
int mold;
uint8_t life_color[4];
uint8_t death_color[4];
uint8_t mold_color[4];
AVLFG lfg;
void (*draw)(AVFilterContext*, AVFrame*);
} LifeContext;
#define ALIVE_CELL 0xFF
#define OFFSET(x) offsetof(LifeContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
static const AVOption life_options[] = {
{ "filename", "set source file", OFFSET(filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
{ "f", "set source file", OFFSET(filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
{ "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, FLAGS },
{ "s", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, FLAGS },
{ "rate", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, FLAGS },
{ "r", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, FLAGS },
{ "rule", "set rule", OFFSET(rule_str), AV_OPT_TYPE_STRING, {.str = "B3/S23"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "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, FLAGS },
{ "ratio", "set fill ratio for filling initial grid randomly", OFFSET(random_fill_ratio), AV_OPT_TYPE_DOUBLE, {.dbl=1/M_PHI}, 0, 1, FLAGS },
{ "random_seed", "set the seed for filling the initial grid randomly", OFFSET(random_seed), AV_OPT_TYPE_INT, {.i64=-1}, -1, UINT32_MAX, FLAGS },
{ "seed", "set the seed for filling the initial grid randomly", OFFSET(random_seed), AV_OPT_TYPE_INT, {.i64=-1}, -1, UINT32_MAX, FLAGS },
{ "stitch", "stitch boundaries", OFFSET(stitch), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, FLAGS },
{ "mold", "set mold speed for dead cells", OFFSET(mold), AV_OPT_TYPE_INT, {.i64=0}, 0, 0xFF, FLAGS },
{ "life_color", "set life color", OFFSET( life_color), AV_OPT_TYPE_COLOR, {.str="white"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "death_color", "set death color", OFFSET(death_color), AV_OPT_TYPE_COLOR, {.str="black"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "mold_color", "set mold color", OFFSET( mold_color), AV_OPT_TYPE_COLOR, {.str="black"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(life);
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->w) {
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_calloc(life->h * life->w, sizeof(*life->buf[0]))) ||
!(life->buf[1] = av_calloc(life->h * life->w, sizeof(*life->buf[1])))) {
av_freep(&life->buf[0]);
av_freep(&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] = av_isgraph(*(p++)) ? ALIVE_CELL : 0;
}
}
life->buf_idx = 0;
return 0;
}
static av_cold int init(AVFilterContext *ctx)
{
LifeContext *life = ctx->priv;
int ret;
if (!life->w && !life->filename)
av_opt_set(life, "size", "320x240", 0);
if ((ret = parse_rule(&life->born_rule, &life->stay_rule, life->rule_str, ctx)) < 0)
return ret;
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");
if (!life->filename) {
/* fill the grid randomly */
int i;
if (!(life->buf[0] = av_calloc(life->h * life->w, sizeof(*life->buf[0]))) ||
!(life->buf[1] = av_calloc(life->h * life->w, sizeof(*life->buf[1])))) {
av_freep(&life->buf[0]);
av_freep(&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_VERBOSE,
"s:%dx%d r:%d/%d rule:%s stay_rule:%d born_rule:%d stitch:%d seed:%"PRIu32"\n",
life->w, life->h, life->frame_rate.num, life->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 = av_inv_q(life->frame_rate);
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
ff_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, AVFrame *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, AVFrame *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;
AVFrame *picref = ff_get_video_buffer(outlink, life->w, life->h);
if (!picref)
return AVERROR(ENOMEM);
picref->sample_aspect_ratio = (AVRational) {1, 1};
picref->pts = life->pts++;
life->draw(outlink->src, picref);
evolve(outlink->src);
#ifdef DEBUG
show_life_grid(outlink->src);
#endif
return ff_filter_frame(outlink, picref);
}
static int query_formats(AVFilterContext *ctx)
{
LifeContext *life = ctx->priv;
enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_NONE, AV_PIX_FMT_NONE };
AVFilterFormats *fmts_list;
if (life->mold || memcmp(life-> life_color, "\xff\xff\xff", 3)
|| memcmp(life->death_color, "\x00\x00\x00", 3)) {
pix_fmts[0] = AV_PIX_FMT_RGB24;
life->draw = fill_picture_rgb;
} else {
pix_fmts[0] = AV_PIX_FMT_MONOBLACK;
life->draw = fill_picture_monoblack;
}
fmts_list = ff_make_format_list(pix_fmts);
return ff_set_common_formats(ctx, fmts_list);
}
static const AVFilterPad life_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.request_frame = request_frame,
.config_props = config_props,
},
{ NULL}
};
AVFilter ff_vsrc_life = {
.name = "life",
.description = NULL_IF_CONFIG_SMALL("Create life."),
.priv_size = sizeof(LifeContext),
.priv_class = &life_class,
.init = init,
.uninit = uninit,
.query_formats = query_formats,
.inputs = NULL,
.outputs = life_outputs,
};