diff options
Diffstat (limited to 'libavfilter/framesync.c')
| -rw-r--r-- | libavfilter/framesync.c | 335 |
1 files changed, 335 insertions, 0 deletions
diff --git a/libavfilter/framesync.c b/libavfilter/framesync.c new file mode 100644 index 0000000000..7920cdb379 --- /dev/null +++ b/libavfilter/framesync.c @@ -0,0 +1,335 @@ +/* + * Copyright (c) 2013 Nicolas George + * + * 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 + */ + +#include "libavutil/avassert.h" +#include "avfilter.h" +#include "bufferqueue.h" +#include "framesync.h" +#include "internal.h" + +#define OFFSET(member) offsetof(FFFrameSync, member) + +static const char *framesync_name(void *ptr) +{ + return "framesync"; +} + +static const AVClass framesync_class = { + .version = LIBAVUTIL_VERSION_INT, + .class_name = "framesync", + .item_name = framesync_name, + .category = AV_CLASS_CATEGORY_FILTER, + .option = NULL, + .parent_log_context_offset = OFFSET(parent), +}; + +enum { + STATE_BOF, + STATE_RUN, + STATE_EOF, +}; + +int ff_framesync_init(FFFrameSync *fs, void *parent, unsigned nb_in) +{ + fs->class = &framesync_class; + fs->parent = parent; + fs->nb_in = nb_in; + + fs->in = av_calloc(nb_in, sizeof(*fs->in)); + if (!fs->in) + return AVERROR(ENOMEM); + return 0; +} + +static void framesync_sync_level_update(FFFrameSync *fs) +{ + unsigned i, level = 0; + + for (i = 0; i < fs->nb_in; i++) + if (fs->in[i].state != STATE_EOF) + level = FFMAX(level, fs->in[i].sync); + av_assert0(level <= fs->sync_level); + if (level < fs->sync_level) + av_log(fs, AV_LOG_VERBOSE, "Sync level %u\n", level); + if (level) + fs->sync_level = level; + else + fs->eof = 1; +} + +int ff_framesync_configure(FFFrameSync *fs) +{ + unsigned i; + int64_t gcd, lcm; + + if (!fs->time_base.num) { + for (i = 0; i < fs->nb_in; i++) { + if (fs->in[i].sync) { + if (fs->time_base.num) { + gcd = av_gcd(fs->time_base.den, fs->in[i].time_base.den); + lcm = (fs->time_base.den / gcd) * fs->in[i].time_base.den; + if (lcm < AV_TIME_BASE / 2) { + fs->time_base.den = lcm; + fs->time_base.num = av_gcd(fs->time_base.num, + fs->in[i].time_base.num); + } else { + fs->time_base.num = 1; + fs->time_base.den = AV_TIME_BASE; + break; + } + } else { + fs->time_base = fs->in[i].time_base; + } + } + } + if (!fs->time_base.num) { + av_log(fs, AV_LOG_ERROR, "Impossible to set time base\n"); + return AVERROR(EINVAL); + } + av_log(fs, AV_LOG_VERBOSE, "Selected %d/%d time base\n", + fs->time_base.num, fs->time_base.den); + } + + for (i = 0; i < fs->nb_in; i++) + fs->in[i].pts = fs->in[i].pts_next = AV_NOPTS_VALUE; + fs->sync_level = UINT_MAX; + framesync_sync_level_update(fs); + + return 0; +} + +static void framesync_advance(FFFrameSync *fs) +{ + int latest; + unsigned i; + int64_t pts; + + if (fs->eof) + return; + while (!fs->frame_ready) { + latest = -1; + for (i = 0; i < fs->nb_in; i++) { + if (!fs->in[i].have_next) { + if (latest < 0 || fs->in[i].pts < fs->in[latest].pts) + latest = i; + } + } + if (latest >= 0) { + fs->in_request = latest; + break; + } + + pts = fs->in[0].pts_next; + for (i = 1; i < fs->nb_in; i++) + if (fs->in[i].pts_next < pts) + pts = fs->in[i].pts_next; + if (pts == INT64_MAX) { + fs->eof = 1; + break; + } + for (i = 0; i < fs->nb_in; i++) { + if (fs->in[i].pts_next == pts || + (fs->in[i].before == EXT_INFINITY && + fs->in[i].state == STATE_BOF)) { + av_frame_free(&fs->in[i].frame); + fs->in[i].frame = fs->in[i].frame_next; + fs->in[i].pts = fs->in[i].pts_next; + fs->in[i].frame_next = NULL; + fs->in[i].pts_next = AV_NOPTS_VALUE; + fs->in[i].have_next = 0; + fs->in[i].state = fs->in[i].frame ? STATE_RUN : STATE_EOF; + if (fs->in[i].sync == fs->sync_level && fs->in[i].frame) + fs->frame_ready = 1; + if (fs->in[i].state == STATE_EOF && + fs->in[i].after == EXT_STOP) + fs->eof = 1; + } + } + if (fs->eof) + fs->frame_ready = 0; + if (fs->frame_ready) + for (i = 0; i < fs->nb_in; i++) + if ((fs->in[i].state == STATE_BOF && + fs->in[i].before == EXT_STOP)) + fs->frame_ready = 0; + fs->pts = pts; + } +} + +static int64_t framesync_pts_extrapolate(FFFrameSync *fs, unsigned in, + int64_t pts) +{ + /* Possible enhancement: use the link's frame rate */ + return pts + 1; +} + +static void framesync_inject_frame(FFFrameSync *fs, unsigned in, AVFrame *frame) +{ + int64_t pts; + + av_assert0(!fs->in[in].have_next); + if (frame) { + pts = av_rescale_q(frame->pts, fs->in[in].time_base, fs->time_base); + frame->pts = pts; + } else { + pts = fs->in[in].state != STATE_RUN || fs->in[in].after == EXT_INFINITY + ? INT64_MAX : framesync_pts_extrapolate(fs, in, fs->in[in].pts); + fs->in[in].sync = 0; + framesync_sync_level_update(fs); + } + fs->in[in].frame_next = frame; + fs->in[in].pts_next = pts; + fs->in[in].have_next = 1; +} + +int ff_framesync_add_frame(FFFrameSync *fs, unsigned in, AVFrame *frame) +{ + av_assert1(in < fs->nb_in); + if (!fs->in[in].have_next) + framesync_inject_frame(fs, in, frame); + else + ff_bufqueue_add(fs, &fs->in[in].queue, frame); + return 0; +} + +void ff_framesync_next(FFFrameSync *fs) +{ + unsigned i; + + av_assert0(!fs->frame_ready); + for (i = 0; i < fs->nb_in; i++) + if (!fs->in[i].have_next && fs->in[i].queue.available) + framesync_inject_frame(fs, i, ff_bufqueue_get(&fs->in[i].queue)); + fs->frame_ready = 0; + framesync_advance(fs); +} + +void ff_framesync_drop(FFFrameSync *fs) +{ + fs->frame_ready = 0; +} + +int ff_framesync_get_frame(FFFrameSync *fs, unsigned in, AVFrame **rframe, + unsigned get) +{ + AVFrame *frame; + unsigned need_copy = 0, i; + int64_t pts_next; + int ret; + + if (!fs->in[in].frame) { + *rframe = NULL; + return 0; + } + frame = fs->in[in].frame; + if (get) { + /* Find out if we need to copy the frame: is there another sync + stream, and do we know if its current frame will outlast this one? */ + pts_next = fs->in[in].have_next ? fs->in[in].pts_next : INT64_MAX; + for (i = 0; i < fs->nb_in && !need_copy; i++) + if (i != in && fs->in[i].sync && + (!fs->in[i].have_next || fs->in[i].pts_next < pts_next)) + need_copy = 1; + if (need_copy) { + if (!(frame = av_frame_clone(frame))) + return AVERROR(ENOMEM); + if ((ret = av_frame_make_writable(frame)) < 0) { + av_frame_free(&frame); + return ret; + } + } else { + fs->in[in].frame = NULL; + } + fs->frame_ready = 0; + } + *rframe = frame; + return 0; +} + +void ff_framesync_uninit(FFFrameSync *fs) +{ + unsigned i; + + for (i = 0; i < fs->nb_in; i++) { + av_frame_free(&fs->in[i].frame); + av_frame_free(&fs->in[i].frame_next); + ff_bufqueue_discard_all(&fs->in[i].queue); + } + + av_freep(&fs->in); +} + +int ff_framesync_process_frame(FFFrameSync *fs, unsigned all) +{ + int ret, count = 0; + + av_assert0(fs->on_event); + while (1) { + ff_framesync_next(fs); + if (fs->eof || !fs->frame_ready) + break; + if ((ret = fs->on_event(fs)) < 0) + return ret; + ff_framesync_drop(fs); + count++; + if (!all) + break; + } + if (!count && fs->eof) + return AVERROR_EOF; + return count; +} + +int ff_framesync_filter_frame(FFFrameSync *fs, AVFilterLink *inlink, + AVFrame *in) +{ + int ret; + + if ((ret = ff_framesync_process_frame(fs, 1)) < 0) + return ret; + if ((ret = ff_framesync_add_frame(fs, FF_INLINK_IDX(inlink), in)) < 0) + return ret; + if ((ret = ff_framesync_process_frame(fs, 0)) < 0) + return ret; + return 0; +} + +int ff_framesync_request_frame(FFFrameSync *fs, AVFilterLink *outlink) +{ + AVFilterContext *ctx = outlink->src; + int input, ret; + + if ((ret = ff_framesync_process_frame(fs, 0)) < 0) + return ret; + if (ret > 0) + return 0; + if (fs->eof) + return AVERROR_EOF; + input = fs->in_request; + ret = ff_request_frame(ctx->inputs[input]); + if (ret == AVERROR_EOF) { + if ((ret = ff_framesync_add_frame(fs, input, NULL)) < 0) + return ret; + if ((ret = ff_framesync_process_frame(fs, 0)) < 0) + return ret; + ret = 0; + } + return ret; +} |