Works for video and audio streams. Similar to the -re option in ffmpeg that only works for input files, and is only implemented for the command line tool, not available in the libraries.
Implementation mostly taken from libavfilter/f_realtime.c. Signed-off-by: Moritz Barsnick <[email protected]> --- doc/bitstream_filters.texi | 16 ++++++++ libavcodec/Makefile | 1 + libavcodec/bitstream_filters.c | 1 + libavcodec/realtime_bsf.c | 90 ++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 108 insertions(+) create mode 100644 libavcodec/realtime_bsf.c diff --git a/doc/bitstream_filters.texi b/doc/bitstream_filters.texi index b779265f58..8c71100460 100644 --- a/doc/bitstream_filters.texi +++ b/doc/bitstream_filters.texi @@ -596,6 +596,22 @@ Set Rec709 colorspace for each frame of the file ffmpeg -i INPUT -c copy -bsf:v prores_metadata=color_primaries=bt709:color_trc=bt709:colorspace=bt709 output.mov @end example +@section realtime + +Slow down output processing to match real time approximately. + +This filter will pause the filtering for a variable amount of time to +match the output rate with the input timestamps. +It is similar to the @option{re} option to @code{ffmpeg}. + +It accepts the following options: + +@table @option +@item limit +Time limit for the pauses. Any pause longer than that will be considered +a timestamp discontinuity and reset the timer. Default is 2 seconds. +@end table + @section remove_extra Remove extradata from packets. diff --git a/libavcodec/Makefile b/libavcodec/Makefile index 08f89ae0b2..a85a5e1fa2 100644 --- a/libavcodec/Makefile +++ b/libavcodec/Makefile @@ -1085,6 +1085,7 @@ OBJS-$(CONFIG_MPEG2_METADATA_BSF) += mpeg2_metadata_bsf.o OBJS-$(CONFIG_NOISE_BSF) += noise_bsf.o OBJS-$(CONFIG_NULL_BSF) += null_bsf.o OBJS-$(CONFIG_PRORES_METADATA_BSF) += prores_metadata_bsf.o +OBJS-$(CONFIG_REALTIME_BSF) += realtime_bsf.o OBJS-$(CONFIG_REMOVE_EXTRADATA_BSF) += remove_extradata_bsf.o OBJS-$(CONFIG_TEXT2MOVSUB_BSF) += movsub_bsf.o OBJS-$(CONFIG_TRACE_HEADERS_BSF) += trace_headers_bsf.o diff --git a/libavcodec/bitstream_filters.c b/libavcodec/bitstream_filters.c index 2c999d3c1d..ba7d3224c4 100644 --- a/libavcodec/bitstream_filters.c +++ b/libavcodec/bitstream_filters.c @@ -48,6 +48,7 @@ extern const AVBitStreamFilter ff_mov2textsub_bsf; extern const AVBitStreamFilter ff_noise_bsf; extern const AVBitStreamFilter ff_null_bsf; extern const AVBitStreamFilter ff_prores_metadata_bsf; +extern const AVBitStreamFilter ff_realtime_bsf; extern const AVBitStreamFilter ff_remove_extradata_bsf; extern const AVBitStreamFilter ff_text2movsub_bsf; extern const AVBitStreamFilter ff_trace_headers_bsf; diff --git a/libavcodec/realtime_bsf.c b/libavcodec/realtime_bsf.c new file mode 100644 index 0000000000..eb4b0b69ed --- /dev/null +++ b/libavcodec/realtime_bsf.c @@ -0,0 +1,90 @@ +/* + * Realtime filter + * Copyright (c) 2015 Nicolas George + * Copyright (c) 2018 Moritz Barsnick + * + * 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/time.h" +#include "libavutil/opt.h" +#include "avcodec.h" +#include "bsf.h" + +typedef struct RealtimeContext { + const AVClass *class; + int64_t delta; + int64_t limit; + unsigned inited; +} RealtimeContext; + +static int realtime_filter(AVBSFContext *bsf, AVPacket *pkt) +{ + int ret; + RealtimeContext *ctx = bsf->priv_data; + + ret = ff_bsf_get_packet_ref(bsf, pkt); + if (ret < 0) + return ret; + + if (pkt->pts != AV_NOPTS_VALUE) { + int64_t pts = av_rescale_q(pkt->pts, bsf->time_base_in, AV_TIME_BASE_Q); + int64_t now = av_gettime_relative(); + int64_t sleep = pts - now + ctx->delta; + if (!ctx->inited) { + ctx->inited = 1; + sleep = 0; + ctx->delta = now - pts; + } + if (sleep > ctx->limit || sleep < -ctx->limit) { + av_log(ctx, AV_LOG_WARNING, + "time discontinuity detected: %"PRIi64" us, resetting\n", + sleep); + sleep = 0; + ctx->delta = now - pts; + } + if (sleep > 0) { + av_log(ctx, AV_LOG_DEBUG, "sleeping %"PRIi64" us\n", sleep); + for (; sleep > 600000000; sleep -= 600000000) + av_usleep(600000000); + av_usleep(sleep); + } + } + + return 0; +} + +#define OFFSET(x) offsetof(RealtimeContext, x) +#define FLAGS (AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_BSF_PARAM) +static const AVOption options[] = { + { "limit", "sleep time limit", OFFSET(limit), AV_OPT_TYPE_DURATION, { .i64 = 2000000 }, 0, INT64_MAX, FLAGS }, + { NULL }, +}; + +static const AVClass realtime_class = { + .class_name = "realtime_bsf", + .item_name = av_default_item_name, + .option = options, + .version = LIBAVUTIL_VERSION_INT, +}; + +const AVBitStreamFilter ff_realtime_bsf = { + .name = "realtime", + .priv_data_size = sizeof(RealtimeContext), + .priv_class = &realtime_class, + .filter = realtime_filter, +}; -- 2.14.5 _______________________________________________ ffmpeg-devel mailing list [email protected] http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
