blob: afdceff7f10607211872ee71c8649705363e3a81
1 | /* |
2 | * Copyright (c) Stefano Sabatini 2011 |
3 | * |
4 | * This file is part of FFmpeg. |
5 | * |
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. |
10 | * |
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. |
15 | * |
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 |
19 | */ |
20 | |
21 | /** |
22 | * @file |
23 | * cellular automaton video source, based on Stephen Wolfram "experimentus crucis" |
24 | */ |
25 | |
26 | /* #define DEBUG */ |
27 | |
28 | #include "libavutil/file.h" |
29 | #include "libavutil/internal.h" |
30 | #include "libavutil/lfg.h" |
31 | #include "libavutil/opt.h" |
32 | #include "libavutil/parseutils.h" |
33 | #include "libavutil/random_seed.h" |
34 | #include "libavutil/avstring.h" |
35 | #include "avfilter.h" |
36 | #include "internal.h" |
37 | #include "formats.h" |
38 | #include "video.h" |
39 | |
40 | typedef struct { |
41 | const AVClass *class; |
42 | int w, h; |
43 | char *filename; |
44 | char *rule_str; |
45 | uint8_t *file_buf; |
46 | size_t file_bufsize; |
47 | uint8_t *buf; |
48 | int buf_prev_row_idx, buf_row_idx; |
49 | uint8_t rule; |
50 | uint64_t pts; |
51 | AVRational frame_rate; |
52 | double random_fill_ratio; |
53 | uint32_t random_seed; |
54 | int stitch, scroll, start_full; |
55 | int64_t generation; ///< the generation number, starting from 0 |
56 | AVLFG lfg; |
57 | char *pattern; |
58 | } CellAutoContext; |
59 | |
60 | #define OFFSET(x) offsetof(CellAutoContext, x) |
61 | #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM |
62 | |
63 | static const AVOption cellauto_options[] = { |
64 | { "filename", "read initial pattern from file", OFFSET(filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS }, |
65 | { "f", "read initial pattern from file", OFFSET(filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS }, |
66 | { "pattern", "set initial pattern", OFFSET(pattern), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS }, |
67 | { "p", "set initial pattern", OFFSET(pattern), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS }, |
68 | { "rate", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, FLAGS }, |
69 | { "r", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, FLAGS }, |
70 | { "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, FLAGS }, |
71 | { "s", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, FLAGS }, |
72 | { "rule", "set rule", OFFSET(rule), AV_OPT_TYPE_INT, {.i64 = 110}, 0, 255, FLAGS }, |
73 | { "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 }, |
74 | { "ratio", "set fill ratio for filling initial grid randomly", OFFSET(random_fill_ratio), AV_OPT_TYPE_DOUBLE, {.dbl = 1/M_PHI}, 0, 1, FLAGS }, |
75 | { "random_seed", "set the seed for filling the initial grid randomly", OFFSET(random_seed), AV_OPT_TYPE_INT, {.i64 = -1}, -1, UINT32_MAX, FLAGS }, |
76 | { "seed", "set the seed for filling the initial grid randomly", OFFSET(random_seed), AV_OPT_TYPE_INT, {.i64 = -1}, -1, UINT32_MAX, FLAGS }, |
77 | { "scroll", "scroll pattern downward", OFFSET(scroll), AV_OPT_TYPE_BOOL, {.i64 = 1}, 0, 1, FLAGS }, |
78 | { "start_full", "start filling the whole video", OFFSET(start_full), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, FLAGS }, |
79 | { "full", "start filling the whole video", OFFSET(start_full), AV_OPT_TYPE_BOOL, {.i64 = 1}, 0, 1, FLAGS }, |
80 | { "stitch", "stitch boundaries", OFFSET(stitch), AV_OPT_TYPE_BOOL, {.i64 = 1}, 0, 1, FLAGS }, |
81 | { NULL } |
82 | }; |
83 | |
84 | AVFILTER_DEFINE_CLASS(cellauto); |
85 | |
86 | #ifdef DEBUG |
87 | static void show_cellauto_row(AVFilterContext *ctx) |
88 | { |
89 | CellAutoContext *s = ctx->priv; |
90 | int i; |
91 | uint8_t *row = s->buf + s->w * s->buf_row_idx; |
92 | char *line = av_malloc(s->w + 1); |
93 | if (!line) |
94 | return; |
95 | |
96 | for (i = 0; i < s->w; i++) |
97 | line[i] = row[i] ? '@' : ' '; |
98 | line[i] = 0; |
99 | av_log(ctx, AV_LOG_DEBUG, "generation:%"PRId64" row:%s|\n", s->generation, line); |
100 | av_free(line); |
101 | } |
102 | #endif |
103 | |
104 | static int init_pattern_from_string(AVFilterContext *ctx) |
105 | { |
106 | CellAutoContext *s = ctx->priv; |
107 | char *p; |
108 | int i, w = 0; |
109 | |
110 | w = strlen(s->pattern); |
111 | av_log(ctx, AV_LOG_DEBUG, "w:%d\n", w); |
112 | |
113 | if (s->w) { |
114 | if (w > s->w) { |
115 | av_log(ctx, AV_LOG_ERROR, |
116 | "The specified width is %d which cannot contain the provided string width of %d\n", |
117 | s->w, w); |
118 | return AVERROR(EINVAL); |
119 | } |
120 | } else { |
121 | /* width was not specified, set it to width of the provided row */ |
122 | s->w = w; |
123 | s->h = (double)s->w * M_PHI; |
124 | } |
125 | |
126 | s->buf = av_mallocz_array(sizeof(uint8_t) * s->w, s->h); |
127 | if (!s->buf) |
128 | return AVERROR(ENOMEM); |
129 | |
130 | /* fill buf */ |
131 | p = s->pattern; |
132 | for (i = (s->w - w)/2;; i++) { |
133 | av_log(ctx, AV_LOG_DEBUG, "%d %c\n", i, *p == '\n' ? 'N' : *p); |
134 | if (*p == '\n' || !*p) |
135 | break; |
136 | else |
137 | s->buf[i] = !!av_isgraph(*(p++)); |
138 | } |
139 | |
140 | return 0; |
141 | } |
142 | |
143 | static int init_pattern_from_file(AVFilterContext *ctx) |
144 | { |
145 | CellAutoContext *s = ctx->priv; |
146 | int ret; |
147 | |
148 | ret = av_file_map(s->filename, |
149 | &s->file_buf, &s->file_bufsize, 0, ctx); |
150 | if (ret < 0) |
151 | return ret; |
152 | |
153 | /* create a string based on the read file */ |
154 | s->pattern = av_malloc(s->file_bufsize + 1); |
155 | if (!s->pattern) |
156 | return AVERROR(ENOMEM); |
157 | memcpy(s->pattern, s->file_buf, s->file_bufsize); |
158 | s->pattern[s->file_bufsize] = 0; |
159 | |
160 | return init_pattern_from_string(ctx); |
161 | } |
162 | |
163 | static av_cold int init(AVFilterContext *ctx) |
164 | { |
165 | CellAutoContext *s = ctx->priv; |
166 | int ret; |
167 | |
168 | if (!s->w && !s->filename && !s->pattern) |
169 | av_opt_set(s, "size", "320x518", 0); |
170 | |
171 | if (s->filename && s->pattern) { |
172 | av_log(ctx, AV_LOG_ERROR, "Only one of the filename or pattern options can be used\n"); |
173 | return AVERROR(EINVAL); |
174 | } |
175 | |
176 | if (s->filename) { |
177 | if ((ret = init_pattern_from_file(ctx)) < 0) |
178 | return ret; |
179 | } else if (s->pattern) { |
180 | if ((ret = init_pattern_from_string(ctx)) < 0) |
181 | return ret; |
182 | } else { |
183 | /* fill the first row randomly */ |
184 | int i; |
185 | |
186 | s->buf = av_mallocz_array(sizeof(uint8_t) * s->w, s->h); |
187 | if (!s->buf) |
188 | return AVERROR(ENOMEM); |
189 | if (s->random_seed == -1) |
190 | s->random_seed = av_get_random_seed(); |
191 | |
192 | av_lfg_init(&s->lfg, s->random_seed); |
193 | |
194 | for (i = 0; i < s->w; i++) { |
195 | double r = (double)av_lfg_get(&s->lfg) / UINT32_MAX; |
196 | if (r <= s->random_fill_ratio) |
197 | s->buf[i] = 1; |
198 | } |
199 | } |
200 | |
201 | av_log(ctx, AV_LOG_VERBOSE, |
202 | "s:%dx%d r:%d/%d rule:%d stitch:%d scroll:%d full:%d seed:%"PRIu32"\n", |
203 | s->w, s->h, s->frame_rate.num, s->frame_rate.den, |
204 | s->rule, s->stitch, s->scroll, s->start_full, |
205 | s->random_seed); |
206 | return 0; |
207 | } |
208 | |
209 | static av_cold void uninit(AVFilterContext *ctx) |
210 | { |
211 | CellAutoContext *s = ctx->priv; |
212 | |
213 | av_file_unmap(s->file_buf, s->file_bufsize); |
214 | av_freep(&s->buf); |
215 | av_freep(&s->pattern); |
216 | } |
217 | |
218 | static int config_props(AVFilterLink *outlink) |
219 | { |
220 | CellAutoContext *s = outlink->src->priv; |
221 | |
222 | outlink->w = s->w; |
223 | outlink->h = s->h; |
224 | outlink->time_base = av_inv_q(s->frame_rate); |
225 | |
226 | return 0; |
227 | } |
228 | |
229 | static void evolve(AVFilterContext *ctx) |
230 | { |
231 | CellAutoContext *s = ctx->priv; |
232 | int i, v, pos[3]; |
233 | uint8_t *row, *prev_row = s->buf + s->buf_row_idx * s->w; |
234 | enum { NW, N, NE }; |
235 | |
236 | s->buf_prev_row_idx = s->buf_row_idx; |
237 | s->buf_row_idx = s->buf_row_idx == s->h-1 ? 0 : s->buf_row_idx+1; |
238 | row = s->buf + s->w * s->buf_row_idx; |
239 | |
240 | for (i = 0; i < s->w; i++) { |
241 | if (s->stitch) { |
242 | pos[NW] = i-1 < 0 ? s->w-1 : i-1; |
243 | pos[N] = i; |
244 | pos[NE] = i+1 == s->w ? 0 : i+1; |
245 | v = prev_row[pos[NW]]<<2 | prev_row[pos[N]]<<1 | prev_row[pos[NE]]; |
246 | } else { |
247 | v = 0; |
248 | v|= i-1 >= 0 ? prev_row[i-1]<<2 : 0; |
249 | v|= prev_row[i ]<<1 ; |
250 | v|= i+1 < s->w ? prev_row[i+1] : 0; |
251 | } |
252 | row[i] = !!(s->rule & (1<<v)); |
253 | ff_dlog(ctx, "i:%d context:%c%c%c -> cell:%d\n", i, |
254 | v&4?'@':' ', v&2?'@':' ', v&1?'@':' ', row[i]); |
255 | } |
256 | |
257 | s->generation++; |
258 | } |
259 | |
260 | static void fill_picture(AVFilterContext *ctx, AVFrame *picref) |
261 | { |
262 | CellAutoContext *s = ctx->priv; |
263 | int i, j, k, row_idx = 0; |
264 | uint8_t *p0 = picref->data[0]; |
265 | |
266 | if (s->scroll && s->generation >= s->h) |
267 | /* show on top the oldest row */ |
268 | row_idx = (s->buf_row_idx + 1) % s->h; |
269 | |
270 | /* fill the output picture with the whole buffer */ |
271 | for (i = 0; i < s->h; i++) { |
272 | uint8_t byte = 0; |
273 | uint8_t *row = s->buf + row_idx*s->w; |
274 | uint8_t *p = p0; |
275 | for (k = 0, j = 0; j < s->w; j++) { |
276 | byte |= row[j]<<(7-k++); |
277 | if (k==8 || j == s->w-1) { |
278 | k = 0; |
279 | *p++ = byte; |
280 | byte = 0; |
281 | } |
282 | } |
283 | row_idx = (row_idx + 1) % s->h; |
284 | p0 += picref->linesize[0]; |
285 | } |
286 | } |
287 | |
288 | static int request_frame(AVFilterLink *outlink) |
289 | { |
290 | CellAutoContext *s = outlink->src->priv; |
291 | AVFrame *picref = ff_get_video_buffer(outlink, s->w, s->h); |
292 | if (!picref) |
293 | return AVERROR(ENOMEM); |
294 | picref->sample_aspect_ratio = (AVRational) {1, 1}; |
295 | if (s->generation == 0 && s->start_full) { |
296 | int i; |
297 | for (i = 0; i < s->h-1; i++) |
298 | evolve(outlink->src); |
299 | } |
300 | fill_picture(outlink->src, picref); |
301 | evolve(outlink->src); |
302 | |
303 | picref->pts = s->pts++; |
304 | |
305 | #ifdef DEBUG |
306 | show_cellauto_row(outlink->src); |
307 | #endif |
308 | return ff_filter_frame(outlink, picref); |
309 | } |
310 | |
311 | static int query_formats(AVFilterContext *ctx) |
312 | { |
313 | static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_MONOBLACK, AV_PIX_FMT_NONE }; |
314 | AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts); |
315 | if (!fmts_list) |
316 | return AVERROR(ENOMEM); |
317 | return ff_set_common_formats(ctx, fmts_list); |
318 | } |
319 | |
320 | static const AVFilterPad cellauto_outputs[] = { |
321 | { |
322 | .name = "default", |
323 | .type = AVMEDIA_TYPE_VIDEO, |
324 | .request_frame = request_frame, |
325 | .config_props = config_props, |
326 | }, |
327 | { NULL } |
328 | }; |
329 | |
330 | AVFilter ff_vsrc_cellauto = { |
331 | .name = "cellauto", |
332 | .description = NULL_IF_CONFIG_SMALL("Create pattern generated by an elementary cellular automaton."), |
333 | .priv_size = sizeof(CellAutoContext), |
334 | .priv_class = &cellauto_class, |
335 | .init = init, |
336 | .uninit = uninit, |
337 | .query_formats = query_formats, |
338 | .inputs = NULL, |
339 | .outputs = cellauto_outputs, |
340 | }; |
341 |