| 1 | /* |
| 2 | * Copyright (c) 2013 Nicolas George |
| 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 License |
| 8 | * 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 |
| 14 | * GNU Lesser General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU Lesser General Public License |
| 17 | * along with FFmpeg; if not, write to the Free Software Foundation, Inc., |
| 18 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 19 | */ |
| 20 | |
| 21 | #include "libavutil/avassert.h" |
| 22 | #include "avfilter.h" |
| 23 | #include "bufferqueue.h" |
| 24 | #include "framesync.h" |
| 25 | #include "internal.h" |
| 26 | |
| 27 | #define OFFSET(member) offsetof(FFFrameSync, member) |
| 28 | |
| 29 | static const char *framesync_name(void *ptr) |
| 30 | { |
| 31 | return "framesync"; |
| 32 | } |
| 33 | |
| 34 | static const AVClass framesync_class = { |
| 35 | .version = LIBAVUTIL_VERSION_INT, |
| 36 | .class_name = "framesync", |
| 37 | .item_name = framesync_name, |
| 38 | .category = AV_CLASS_CATEGORY_FILTER, |
| 39 | .option = NULL, |
| 40 | .parent_log_context_offset = OFFSET(parent), |
| 41 | }; |
| 42 | |
| 43 | enum { |
| 44 | STATE_BOF, |
| 45 | STATE_RUN, |
| 46 | STATE_EOF, |
| 47 | }; |
| 48 | |
| 49 | void ff_framesync_init(FFFrameSync *fs, void *parent, unsigned nb_in) |
| 50 | { |
| 51 | fs->class = &framesync_class; |
| 52 | fs->parent = parent; |
| 53 | fs->nb_in = nb_in; |
| 54 | } |
| 55 | |
| 56 | static void framesync_sync_level_update(FFFrameSync *fs) |
| 57 | { |
| 58 | unsigned i, level = 0; |
| 59 | |
| 60 | for (i = 0; i < fs->nb_in; i++) |
| 61 | if (fs->in[i].state != STATE_EOF) |
| 62 | level = FFMAX(level, fs->in[i].sync); |
| 63 | av_assert0(level <= fs->sync_level); |
| 64 | if (level < fs->sync_level) |
| 65 | av_log(fs, AV_LOG_VERBOSE, "Sync level %u\n", level); |
| 66 | if (level) |
| 67 | fs->sync_level = level; |
| 68 | else |
| 69 | fs->eof = 1; |
| 70 | } |
| 71 | |
| 72 | int ff_framesync_configure(FFFrameSync *fs) |
| 73 | { |
| 74 | unsigned i; |
| 75 | int64_t gcd, lcm; |
| 76 | |
| 77 | if (!fs->time_base.num) { |
| 78 | for (i = 0; i < fs->nb_in; i++) { |
| 79 | if (fs->in[i].sync) { |
| 80 | if (fs->time_base.num) { |
| 81 | gcd = av_gcd(fs->time_base.den, fs->in[i].time_base.den); |
| 82 | lcm = (fs->time_base.den / gcd) * fs->in[i].time_base.den; |
| 83 | if (lcm < AV_TIME_BASE / 2) { |
| 84 | fs->time_base.den = lcm; |
| 85 | fs->time_base.num = av_gcd(fs->time_base.num, |
| 86 | fs->in[i].time_base.num); |
| 87 | } else { |
| 88 | fs->time_base.num = 1; |
| 89 | fs->time_base.den = AV_TIME_BASE; |
| 90 | break; |
| 91 | } |
| 92 | } else { |
| 93 | fs->time_base = fs->in[i].time_base; |
| 94 | } |
| 95 | } |
| 96 | } |
| 97 | if (!fs->time_base.num) { |
| 98 | av_log(fs, AV_LOG_ERROR, "Impossible to set time base\n"); |
| 99 | return AVERROR(EINVAL); |
| 100 | } |
| 101 | av_log(fs, AV_LOG_VERBOSE, "Selected %d/%d time base\n", |
| 102 | fs->time_base.num, fs->time_base.den); |
| 103 | } |
| 104 | |
| 105 | for (i = 0; i < fs->nb_in; i++) |
| 106 | fs->in[i].pts = fs->in[i].pts_next = AV_NOPTS_VALUE; |
| 107 | fs->sync_level = UINT_MAX; |
| 108 | framesync_sync_level_update(fs); |
| 109 | |
| 110 | return 0; |
| 111 | } |
| 112 | |
| 113 | static void framesync_advance(FFFrameSync *fs) |
| 114 | { |
| 115 | int latest; |
| 116 | unsigned i; |
| 117 | int64_t pts; |
| 118 | |
| 119 | if (fs->eof) |
| 120 | return; |
| 121 | while (!fs->frame_ready) { |
| 122 | latest = -1; |
| 123 | for (i = 0; i < fs->nb_in; i++) { |
| 124 | if (!fs->in[i].have_next) { |
| 125 | if (latest < 0 || fs->in[i].pts < fs->in[latest].pts) |
| 126 | latest = i; |
| 127 | } |
| 128 | } |
| 129 | if (latest >= 0) { |
| 130 | fs->in_request = latest; |
| 131 | break; |
| 132 | } |
| 133 | |
| 134 | pts = fs->in[0].pts_next; |
| 135 | for (i = 1; i < fs->nb_in; i++) |
| 136 | if (fs->in[i].pts_next < pts) |
| 137 | pts = fs->in[i].pts_next; |
| 138 | if (pts == INT64_MAX) { |
| 139 | fs->eof = 1; |
| 140 | break; |
| 141 | } |
| 142 | for (i = 0; i < fs->nb_in; i++) { |
| 143 | if (fs->in[i].pts_next == pts || |
| 144 | (fs->in[i].before == EXT_INFINITY && |
| 145 | fs->in[i].state == STATE_BOF)) { |
| 146 | av_frame_free(&fs->in[i].frame); |
| 147 | fs->in[i].frame = fs->in[i].frame_next; |
| 148 | fs->in[i].pts = fs->in[i].pts_next; |
| 149 | fs->in[i].frame_next = NULL; |
| 150 | fs->in[i].pts_next = AV_NOPTS_VALUE; |
| 151 | fs->in[i].have_next = 0; |
| 152 | fs->in[i].state = fs->in[i].frame ? STATE_RUN : STATE_EOF; |
| 153 | if (fs->in[i].sync == fs->sync_level && fs->in[i].frame) |
| 154 | fs->frame_ready = 1; |
| 155 | if (fs->in[i].state == STATE_EOF && |
| 156 | fs->in[i].after == EXT_STOP) |
| 157 | fs->eof = 1; |
| 158 | } |
| 159 | } |
| 160 | if (fs->eof) |
| 161 | fs->frame_ready = 0; |
| 162 | if (fs->frame_ready) |
| 163 | for (i = 0; i < fs->nb_in; i++) |
| 164 | if ((fs->in[i].state == STATE_BOF && |
| 165 | fs->in[i].before == EXT_STOP)) |
| 166 | fs->frame_ready = 0; |
| 167 | fs->pts = pts; |
| 168 | } |
| 169 | } |
| 170 | |
| 171 | static int64_t framesync_pts_extrapolate(FFFrameSync *fs, unsigned in, |
| 172 | int64_t pts) |
| 173 | { |
| 174 | /* Possible enhancement: use the link's frame rate */ |
| 175 | return pts + 1; |
| 176 | } |
| 177 | |
| 178 | static void framesync_inject_frame(FFFrameSync *fs, unsigned in, AVFrame *frame) |
| 179 | { |
| 180 | int64_t pts; |
| 181 | |
| 182 | av_assert0(!fs->in[in].have_next); |
| 183 | if (frame) { |
| 184 | pts = av_rescale_q(frame->pts, fs->in[in].time_base, fs->time_base); |
| 185 | frame->pts = pts; |
| 186 | } else { |
| 187 | pts = fs->in[in].state != STATE_RUN || fs->in[in].after == EXT_INFINITY |
| 188 | ? INT64_MAX : framesync_pts_extrapolate(fs, in, fs->in[in].pts); |
| 189 | fs->in[in].sync = 0; |
| 190 | framesync_sync_level_update(fs); |
| 191 | } |
| 192 | fs->in[in].frame_next = frame; |
| 193 | fs->in[in].pts_next = pts; |
| 194 | fs->in[in].have_next = 1; |
| 195 | } |
| 196 | |
| 197 | int ff_framesync_add_frame(FFFrameSync *fs, unsigned in, AVFrame *frame) |
| 198 | { |
| 199 | av_assert1(in < fs->nb_in); |
| 200 | if (!fs->in[in].have_next) |
| 201 | framesync_inject_frame(fs, in, frame); |
| 202 | else |
| 203 | ff_bufqueue_add(fs, &fs->in[in].queue, frame); |
| 204 | return 0; |
| 205 | } |
| 206 | |
| 207 | void ff_framesync_next(FFFrameSync *fs) |
| 208 | { |
| 209 | unsigned i; |
| 210 | |
| 211 | av_assert0(!fs->frame_ready); |
| 212 | for (i = 0; i < fs->nb_in; i++) |
| 213 | if (!fs->in[i].have_next && fs->in[i].queue.available) |
| 214 | framesync_inject_frame(fs, i, ff_bufqueue_get(&fs->in[i].queue)); |
| 215 | fs->frame_ready = 0; |
| 216 | framesync_advance(fs); |
| 217 | } |
| 218 | |
| 219 | void ff_framesync_drop(FFFrameSync *fs) |
| 220 | { |
| 221 | fs->frame_ready = 0; |
| 222 | } |
| 223 | |
| 224 | int ff_framesync_get_frame(FFFrameSync *fs, unsigned in, AVFrame **rframe, |
| 225 | unsigned get) |
| 226 | { |
| 227 | AVFrame *frame; |
| 228 | unsigned need_copy = 0, i; |
| 229 | int64_t pts_next; |
| 230 | int ret; |
| 231 | |
| 232 | if (!fs->in[in].frame) { |
| 233 | *rframe = NULL; |
| 234 | return 0; |
| 235 | } |
| 236 | frame = fs->in[in].frame; |
| 237 | if (get) { |
| 238 | /* Find out if we need to copy the frame: is there another sync |
| 239 | stream, and do we know if its current frame will outlast this one? */ |
| 240 | pts_next = fs->in[in].have_next ? fs->in[in].pts_next : INT64_MAX; |
| 241 | for (i = 0; i < fs->nb_in && !need_copy; i++) |
| 242 | if (i != in && fs->in[i].sync && |
| 243 | (!fs->in[i].have_next || fs->in[i].pts_next < pts_next)) |
| 244 | need_copy = 1; |
| 245 | if (need_copy) { |
| 246 | if (!(frame = av_frame_clone(frame))) |
| 247 | return AVERROR(ENOMEM); |
| 248 | if ((ret = av_frame_make_writable(frame)) < 0) { |
| 249 | av_frame_free(&frame); |
| 250 | return ret; |
| 251 | } |
| 252 | } else { |
| 253 | fs->in[in].frame = NULL; |
| 254 | } |
| 255 | fs->frame_ready = 0; |
| 256 | } |
| 257 | *rframe = frame; |
| 258 | return 0; |
| 259 | } |
| 260 | |
| 261 | void ff_framesync_uninit(FFFrameSync *fs) |
| 262 | { |
| 263 | unsigned i; |
| 264 | |
| 265 | for (i = 0; i < fs->nb_in; i++) { |
| 266 | av_frame_free(&fs->in[i].frame); |
| 267 | av_frame_free(&fs->in[i].frame_next); |
| 268 | ff_bufqueue_discard_all(&fs->in[i].queue); |
| 269 | } |
| 270 | } |
| 271 | |
| 272 | int ff_framesync_process_frame(FFFrameSync *fs, unsigned all) |
| 273 | { |
| 274 | int ret, count = 0; |
| 275 | |
| 276 | av_assert0(fs->on_event); |
| 277 | while (1) { |
| 278 | ff_framesync_next(fs); |
| 279 | if (fs->eof || !fs->frame_ready) |
| 280 | break; |
| 281 | if ((ret = fs->on_event(fs)) < 0) |
| 282 | return ret; |
| 283 | ff_framesync_drop(fs); |
| 284 | count++; |
| 285 | if (!all) |
| 286 | break; |
| 287 | } |
| 288 | if (!count && fs->eof) |
| 289 | return AVERROR_EOF; |
| 290 | return count; |
| 291 | } |
| 292 | |
| 293 | int ff_framesync_filter_frame(FFFrameSync *fs, AVFilterLink *inlink, |
| 294 | AVFrame *in) |
| 295 | { |
| 296 | int ret; |
| 297 | |
| 298 | if ((ret = ff_framesync_process_frame(fs, 1)) < 0) |
| 299 | return ret; |
| 300 | if ((ret = ff_framesync_add_frame(fs, FF_INLINK_IDX(inlink), in)) < 0) |
| 301 | return ret; |
| 302 | if ((ret = ff_framesync_process_frame(fs, 0)) < 0) |
| 303 | return ret; |
| 304 | return 0; |
| 305 | } |
| 306 | |
| 307 | int ff_framesync_request_frame(FFFrameSync *fs, AVFilterLink *outlink) |
| 308 | { |
| 309 | AVFilterContext *ctx = outlink->src; |
| 310 | int input, ret; |
| 311 | |
| 312 | if ((ret = ff_framesync_process_frame(fs, 0)) < 0) |
| 313 | return ret; |
| 314 | if (ret > 0) |
| 315 | return 0; |
| 316 | if (fs->eof) |
| 317 | return AVERROR_EOF; |
| 318 | outlink->flags |= FF_LINK_FLAG_REQUEST_LOOP; |
| 319 | input = fs->in_request; |
| 320 | ret = ff_request_frame(ctx->inputs[input]); |
| 321 | if (ret == AVERROR_EOF) { |
| 322 | if ((ret = ff_framesync_add_frame(fs, input, NULL)) < 0) |
| 323 | return ret; |
| 324 | if ((ret = ff_framesync_process_frame(fs, 0)) < 0) |
| 325 | return ret; |
| 326 | ret = 0; |
| 327 | } |
| 328 | return ret; |
| 329 | } |