diff --git a/libavfilter/framesync2.c b/libavfilter/framesync2.c new file mode 100644 index 0000000000000000000000000000000000000000..eb05d66a86eb6365ad2752bc1dbc248af68cbacc --- /dev/null +++ b/libavfilter/framesync2.c @@ -0,0 +1,343 @@ +/* + * 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 + */ + +#define FF_INTERNAL_FIELDS 1 +#include "framequeue.h" + +#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, i; + + 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; + /* Detect status change early */ + for (i = 0; i < fs->nb_in; i++) + if (!ff_framequeue_queued_frames(&ctx->inputs[i]->fifo) && + ctx->inputs[i]->status_in && !ctx->inputs[i]->status_out) + input = i; + 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; +} diff --git a/libavfilter/framesync2.h b/libavfilter/framesync2.h new file mode 100644 index 0000000000000000000000000000000000000000..074d30394f1c761f2025b7ac5f104b5d5ef90ffe --- /dev/null +++ b/libavfilter/framesync2.h @@ -0,0 +1,297 @@ +/* + * 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 + */ + +#ifndef AVFILTER_FRAMESYNC2_H +#define AVFILTER_FRAMESYNC2_H + +#include "bufferqueue.h" + +/* + * TODO + * Callback-based API similar to dualinput. + * Export convenient options. + */ + +/** + * This API is intended as a helper for filters that have several video + * input and need to combine them somehow. If the inputs have different or + * variable frame rate, getting the input frames to match requires a rather + * complex logic and a few user-tunable options. + * + * In this API, when a set of synchronized input frames is ready to be + * procesed is called a frame event. Frame event can be generated in + * response to input frames on any or all inputs and the handling of + * situations where some stream extend beyond the beginning or the end of + * others can be configured. + * + * The basic working of this API is the following: + * + * - When a frame is available on any input, add it using + * ff_framesync_add_frame(). + * + * - When a frame event is ready to be processed (i.e. after adding a frame + * or when requested on input): + * - call ff_framesync_next(); + * - if fs->frame_ready is true, process the frames; + * - call ff_framesync_drop(). + */ + +/** + * Stream extrapolation mode + * + * Describe how the frames of a stream are extrapolated before the first one + * and after EOF to keep sync with possibly longer other streams. + */ +enum FFFrameSyncExtMode { + + /** + * Completely stop all streams with this one. + */ + EXT_STOP, + + /** + * Ignore this stream and continue processing the other ones. + */ + EXT_NULL, + + /** + * Extend the frame to infinity. + */ + EXT_INFINITY, +}; + +/** + * Input stream structure + */ +typedef struct FFFrameSyncIn { + + /** + * Queue of incoming AVFrame, and NULL to mark EOF + */ + struct FFBufQueue queue; + + /** + * Extrapolation mode for timestamps before the first frame + */ + enum FFFrameSyncExtMode before; + + /** + * Extrapolation mode for timestamps after the last frame + */ + enum FFFrameSyncExtMode after; + + /** + * Time base for the incoming frames + */ + AVRational time_base; + + /** + * Current frame, may be NULL before the first one or after EOF + */ + AVFrame *frame; + + /** + * Next frame, for internal use + */ + AVFrame *frame_next; + + /** + * PTS of the current frame + */ + int64_t pts; + + /** + * PTS of the next frame, for internal use + */ + int64_t pts_next; + + /** + * Boolean flagging the next frame, for internal use + */ + uint8_t have_next; + + /** + * State: before first, in stream or after EOF, for internal use + */ + uint8_t state; + + /** + * Synchronization level: frames on input at the highest sync level will + * generate output frame events. + * + * For example, if inputs #0 and #1 have sync level 2 and input #2 has + * sync level 1, then a frame on either input #0 or #1 will generate a + * frame event, but not a frame on input #2 until both inputs #0 and #1 + * have reached EOF. + * + * If sync is 0, no frame event will be generated. + */ + unsigned sync; + +} FFFrameSyncIn; + +/** + * Frame sync structure. + */ +typedef struct FFFrameSync { + const AVClass *class; + void *parent; + + /** + * Number of input streams + */ + unsigned nb_in; + + /** + * Time base for the output events + */ + AVRational time_base; + + /** + * Timestamp of the current event + */ + int64_t pts; + + /** + * Callback called when a frame event is ready + */ + int (*on_event)(struct FFFrameSync *fs); + + /** + * Opaque pointer, not used by the API + */ + void *opaque; + + /** + * Index of the input that requires a request + */ + unsigned in_request; + + /** + * Synchronization level: only inputs with the same sync level are sync + * sources. + */ + unsigned sync_level; + + /** + * Flag indicating that a frame event is ready + */ + uint8_t frame_ready; + + /** + * Flag indicating that output has reached EOF. + */ + uint8_t eof; + + /** + * Pointer to array of inputs. + */ + FFFrameSyncIn *in; + +} FFFrameSync; + +/** + * Initialize a frame sync structure. + * + * The entire structure is expected to be already set to 0. + * + * @param fs frame sync structure to initialize + * @param parent parent object, used for logging + * @param nb_in number of inputs + * @return >= 0 for success or a negative error code + */ +int ff_framesync_init(FFFrameSync *fs, void *parent, unsigned nb_in); + +/** + * Configure a frame sync structure. + * + * Must be called after all options are set but before all use. + * + * @return >= 0 for success or a negative error code + */ +int ff_framesync_configure(FFFrameSync *fs); + +/** + * Free all memory currently allocated. + */ +void ff_framesync_uninit(FFFrameSync *fs); + +/** + * Add a frame to an input + * + * Typically called from the filter_frame() method. + * + * @param fs frame sync structure + * @param in index of the input + * @param frame input frame, or NULL for EOF + */ +int ff_framesync_add_frame(FFFrameSync *fs, unsigned in, AVFrame *frame); + +/** + * Prepare the next frame event. + * + * The status of the operation can be found in fs->frame_ready and fs->eof. + */ +void ff_framesync_next(FFFrameSync *fs); + +/** + * Drop the current frame event. + */ +void ff_framesync_drop(FFFrameSync *fs); + +/** + * Get the current frame in an input. + * + * @param fs frame sync structure + * @param in index of the input + * @param rframe used to return the current frame (or NULL) + * @param get if not zero, the calling code needs to get ownership of + * the returned frame; the current frame will either be + * duplicated or removed from the framesync structure + */ +int ff_framesync_get_frame(FFFrameSync *fs, unsigned in, AVFrame **rframe, + unsigned get); + +/** + * Process one or several frame using the on_event callback. + * + * @return number of frames processed or negative error code + */ +int ff_framesync_process_frame(FFFrameSync *fs, unsigned all); + + +/** + * Accept a frame on a filter input. + * + * This function can be the complete implementation of all filter_frame + * methods of a filter using framesync. + */ +int ff_framesync_filter_frame(FFFrameSync *fs, AVFilterLink *inlink, + AVFrame *in); + +/** + * Request a frame on the filter output. + * + * This function can be the complete implementation of all filter_frame + * methods of a filter using framesync if it has only one output. + */ +int ff_framesync_request_frame(FFFrameSync *fs, AVFilterLink *outlink); + +#endif /* AVFILTER_FRAMESYNC2_H */