[FFmpeg-devel] [PATCH 3/4] V11 - SCTE-35 support in hlsenc
Steven Liu
lingjiujianke at gmail.com
Wed Sep 28 11:33:05 EEST 2016
2016-09-28 4:38 GMT+08:00 Carlos Fernandez Sanz <carlos at ccextractor.org>:
> From: Carlos Fernandez <carlos at ccextractor.org>
>
> Signed-off-by: Carlos Fernandez <carlos at ccextractor.org>
> ---
> libavformat/Makefile | 2 +-
> libavformat/hlsenc.c | 108 +++++++++--
> libavformat/scte_35.c | 527 ++++++++++++++++++++++++++++++
> ++++++++++++++++++++
> libavformat/scte_35.h | 86 ++++++++
> 4 files changed, 701 insertions(+), 22 deletions(-)
> create mode 100644 libavformat/scte_35.c
> create mode 100644 libavformat/scte_35.h
>
> diff --git a/libavformat/Makefile b/libavformat/Makefile
> index 5d827d31..9218606 100644
> --- a/libavformat/Makefile
> +++ b/libavformat/Makefile
> @@ -205,7 +205,7 @@ OBJS-$(CONFIG_HDS_MUXER) += hdsenc.o
> OBJS-$(CONFIG_HEVC_DEMUXER) += hevcdec.o rawdec.o
> OBJS-$(CONFIG_HEVC_MUXER) += rawenc.o
> OBJS-$(CONFIG_HLS_DEMUXER) += hls.o
> -OBJS-$(CONFIG_HLS_MUXER) += hlsenc.o
> +OBJS-$(CONFIG_HLS_MUXER) += hlsenc.o scte_35.o
> OBJS-$(CONFIG_HNM_DEMUXER) += hnm.o
> OBJS-$(CONFIG_ICO_DEMUXER) += icodec.o
> OBJS-$(CONFIG_ICO_MUXER) += icoenc.o
> diff --git a/libavformat/hlsenc.c b/libavformat/hlsenc.c
> index 428bae4..3303dc8 100644
> --- a/libavformat/hlsenc.c
> +++ b/libavformat/hlsenc.c
> @@ -38,6 +38,7 @@
> #include "avio_internal.h"
> #include "internal.h"
> #include "os_support.h"
> +#include "scte_35.h"
>
> #define KEYSIZE 16
> #define LINE_BUFFER_SIZE 1024
> @@ -48,6 +49,10 @@ typedef struct HLSSegment {
> double duration; /* in seconds */
> int64_t pos;
> int64_t size;
> + struct scte_35_event *event;
> + int out;
> + int adv_count;
> + int64_t start_pts;
>
> char key_uri[LINE_BUFFER_SIZE + 1];
> char iv_string[KEYSIZE*2 + 1];
> @@ -92,6 +97,8 @@ typedef struct HLSContext {
> uint32_t flags; // enum HLSFlags
> uint32_t pl_type; // enum PlaylistType
> char *segment_filename;
> + char *adv_filename;
> + char *adv_subfilename;
>
> int use_localtime; ///< flag to expand filename with localtime
> int use_localtime_mkdir;///< flag to mkdir dirname in timebased
> filename
> @@ -108,6 +115,8 @@ typedef struct HLSContext {
> int nb_entries;
> int discontinuity_set;
>
> + int adv_count;
> + struct scte_35_interface *scte_iface;
> HLSSegment *segments;
> HLSSegment *last_segment;
> HLSSegment *old_segments;
> @@ -208,6 +217,8 @@ static int hls_delete_old_segments(HLSContext *hls) {
> av_freep(&path);
> previous_segment = segment;
> segment = previous_segment->next;
> + if (hls->scte_iface)
> + hls->scte_iface->unref_scte35_event(&previous_segment->
> event);
> av_free(previous_segment);
> }
>
> @@ -327,8 +338,8 @@ static int hls_mux_init(AVFormatContext *s)
> }
>
> /* Create a new segment and append it to the segment list */
> -static int hls_append_segment(struct AVFormatContext *s, HLSContext *hls,
> double duration,
> - int64_t pos, int64_t size)
> +static int hls_append_segment(struct AVFormatContext *s, HLSContext *hls,
> double duration, int64_t pos,
> + int64_t start_pts, struct scte_35_event
> *event, int64_t size)
> {
> HLSSegment *en = av_malloc(sizeof(*en));
> char *tmp, *p;
> @@ -364,9 +375,23 @@ static int hls_append_segment(struct AVFormatContext
> *s, HLSContext *hls, double
>
> en->duration = duration;
> en->pos = pos;
> + en->event = event;
> en->size = size;
> + en->start_pts = start_pts;
> en->next = NULL;
>
> + if (hls->scte_iface) {
> + if (hls->scte_iface->event_state == EVENT_OUT_CONT) {
> + en->adv_count = hls->adv_count;;
> + hls->adv_count++;
> + en->out = hls->scte_iface->event_state;
> + } else {
> + hls->adv_count = 0;
> + en->out = hls->scte_iface->event_state;
> + }
> + }
> +
> +
> if (hls->key_info_file) {
> av_strlcpy(en->key_uri, hls->key_uri, sizeof(en->key_uri));
> av_strlcpy(en->iv_string, hls->iv_string, sizeof(en->iv_string));
> @@ -440,7 +465,7 @@ static int parse_playlist(AVFormatContext *s, const
> char *url)
> new_start_pos = avio_tell(hls->avf->pb);
> hls->size = new_start_pos - hls->start_pos;
> av_strlcpy(hls->avf->filename, line, sizeof(line));
> - ret = hls_append_segment(s, hls, hls->duration,
> hls->start_pos, hls->size);
> + ret = hls_append_segment(s, hls, hls->duration,
> hls->start_pos, 0, NULL, hls->size);
> if (ret < 0)
> goto fail;
> hls->start_pos = new_start_pos;
> @@ -570,9 +595,23 @@ static int hls_window(AVFormatContext *s, int last)
> avio_printf(out, "#EXT-X-PROGRAM-DATE-TIME:%s.%03d%s\n",
> buf0, milli, buf1);
> prog_date_time += en->duration;
> }
> - if (hls->baseurl)
> - avio_printf(out, "%s", hls->baseurl);
> - avio_printf(out, "%s\n", en->filename);
> + if (hls->scte_iface && (en->event || en->out) ) {
> + char *str;
> + char fname[1024] = "";
> + if (hls->adv_filename) {
> + str = hls->scte_iface->get_hls_string(hls->scte_iface,
> en->event, hls->adv_filename, en->out, en->adv_count, en->start_pts);
> + } else {
> + if (hls->baseurl)
> + strncat(fname, hls->baseurl, 1024);
>
if（strlen(fname) >= 1024）
av_log(s, AV_LOG_WARNING, "the fname is too long, so your filename will be
ignore\n");
> + strncat(fname, en->filename, 1024 - strlen(fname) );
> + str = hls->scte_iface->get_hls_string(hls->scte_iface,
> en->event, fname, en->out, -1, en->start_pts);
> + }
> + avio_printf(out, "%s", str);
> + } else {
> + if (hls->baseurl)
> + avio_printf(out, "%s", hls->baseurl);
> + avio_printf(out, "%s\n", en->filename);
> + }
> }
>
> if (last && (hls->flags & HLS_OMIT_ENDLIST)==0)
> @@ -597,9 +636,15 @@ static int hls_window(AVFormatContext *s, int last)
> if (byterange_mode)
> avio_printf(sub_out, "#EXT-X-BYTERANGE:%"PRIi64"@%"
> PRIi64"\n",
> en->size, en->pos);
> - if (hls->baseurl)
> - avio_printf(sub_out, "%s", hls->baseurl);
> - avio_printf(sub_out, "%s\n", en->sub_filename);
> + if (hls->scte_iface && (en->event || en->out) ) {
> + char *str = hls->scte_iface->get_hls_string(hls->scte_iface,
> en->event, hls->adv_subfilename, en->out, en->adv_count, en->pos);
> + avio_printf(out, "%s", str);
> + } else {
> + if (hls->baseurl)
> + avio_printf(out, "%s", hls->baseurl);
> + avio_printf(sub_out, "%s\n", en->sub_filename);
> + }
> +
> }
>
> if (last)
> @@ -749,6 +794,7 @@ static int hls_write_header(AVFormatContext *s)
> AVDictionary *options = NULL;
> int basename_size;
> int vtt_basename_size;
> + int ts_index = 0;
>
> hls->sequence = hls->start_sequence;
> hls->recording_time = (hls->init_time ? hls->init_time : hls->time) *
> AV_TIME_BASE;
> @@ -881,7 +927,7 @@ static int hls_write_header(AVFormatContext *s)
> goto fail;
> }
> //av_assert0(s->nb_streams == hls->avf->nb_streams);
> - for (i = 0; i < s->nb_streams; i++) {
> + for (ts_index = 0, i = 0; i < s->nb_streams; i++) {
> AVStream *inner_st;
> AVStream *outer_st = s->streams[i];
>
> @@ -894,16 +940,18 @@ static int hls_write_header(AVFormatContext *s)
> }
> }
>
> - if (outer_st->codecpar->codec_type != AVMEDIA_TYPE_SUBTITLE)
> - inner_st = hls->avf->streams[i];
> - else if (hls->vtt_avf)
> + if (hls->vtt_avf && outer_st->codecpar->codec_type ==
> AVMEDIA_TYPE_SUBTITLE) {
> inner_st = hls->vtt_avf->streams[0];
> - else {
> - /* We have a subtitle stream, when the user does not want one
> */
> - inner_st = NULL;
> + avpriv_set_pts_info(outer_st, inner_st->pts_wrap_bits,
> inner_st->time_base.num, inner_st->time_base.den);
> + } else if (outer_st->codecpar->codec_type == AVMEDIA_TYPE_DATA) {
> + inner_st = hls->avf->streams[ts_index];
> + hls->scte_iface = ff_alloc_scte35_parser(hls,
> outer_st->time_base);
> continue;
> + } else {
> + inner_st = hls->avf->streams[ts_index];
> + avpriv_set_pts_info(outer_st, inner_st->pts_wrap_bits,
> inner_st->time_base.num, inner_st->time_base.den);
> + ts_index++;
> }
> - avpriv_set_pts_info(outer_st, inner_st->pts_wrap_bits,
> inner_st->time_base.num, inner_st->time_base.den);
> }
> fail:
>
> @@ -929,6 +977,12 @@ static int hls_write_packet(AVFormatContext *s,
> AVPacket *pkt)
> int is_ref_pkt = 1;
> int ret, can_split = 1;
> int stream_index = 0;
> + struct scte_35_event *event = NULL;
> +
> + if (st->codecpar->codec_id == AV_CODEC_ID_SCTE_35) {
> + ret = ff_parse_scte35_pkt(hls->scte_iface, pkt);
> + return ret;
> + }
>
> if (hls->sequence - hls->nb_entries > hls->start_sequence &&
> hls->init_time > 0) {
> /* reset end_pts, hls->recording_time at end of the init hls list
> */
> @@ -962,14 +1016,24 @@ static int hls_write_packet(AVFormatContext *s,
> AVPacket *pkt)
> hls->duration = (double)(pkt->pts - hls->end_pts)
> * st->time_base.num /
> st->time_base.den;
>
> - if (can_split && av_compare_ts(pkt->pts - hls->start_pts,
> st->time_base,
> - end_pts, AV_TIME_BASE_Q) >= 0) {
> + if (hls->scte_iface)
> + hls->scte_iface->update_video_pts(hls->scte_iface, pkt->pts *
> st->time_base.num / st->time_base.den);
> +
> +
> + if (can_split && (( av_compare_ts(pkt->pts - hls->start_pts,
> st->time_base,
> + end_pts, AV_TIME_BASE_Q) >= 0) ||
> + (hls->scte_iface && hls->scte_iface->event_state == EVENT_OUT))
> ) {
> int64_t new_start_pos;
> av_write_frame(oc, NULL); /* Flush any buffered data */
>
> new_start_pos = avio_tell(hls->avf->pb);
> hls->size = new_start_pos - hls->start_pos;
> - ret = hls_append_segment(s, hls, hls->duration, hls->start_pos,
> hls->size);
> + if (hls->scte_iface) {
> + event = hls->scte_iface->update_event_state(hls->scte_iface);
> + if (event)
> + hls->scte_iface->ref_scte35_event(event);
> + }
> + ret = hls_append_segment(s, hls, hls->duration, hls->start_pos,
> pkt->pts, event, hls->size);
> hls->start_pos = new_start_pos;
> if (ret < 0)
> return ret;
> @@ -1031,7 +1095,7 @@ static int hls_write_trailer(struct AVFormatContext
> *s)
> if (oc->pb) {
> hls->size = avio_tell(hls->avf->pb) - hls->start_pos;
> ff_format_io_close(s, &oc->pb);
> - hls_append_segment(s, hls, hls->duration, hls->start_pos,
> hls->size);
> + hls_append_segment(s, hls, hls->duration, hls->start_pos,
> hls->end_pts, NULL, hls->size);
> }
>
> if (vtt_oc) {
> @@ -1052,6 +1116,7 @@ static int hls_write_trailer(struct AVFormatContext
> *s)
> avformat_free_context(vtt_oc);
> }
>
> + ff_delete_scte35_parser(hls->scte_iface);
> hls_free_segments(hls->segments);
> hls_free_segments(hls->old_segments);
> return 0;
> @@ -1108,6 +1173,7 @@ AVOutputFormat ff_hls_muxer = {
> .audio_codec = AV_CODEC_ID_AAC,
> .video_codec = AV_CODEC_ID_H264,
> .subtitle_codec = AV_CODEC_ID_WEBVTT,
> + .data_codec = AV_CODEC_ID_SCTE_35,
> .flags = AVFMT_NOFILE | AVFMT_ALLOW_FLUSH,
> .write_header = hls_write_header,
> .write_packet = hls_write_packet,
> diff --git a/libavformat/scte_35.c b/libavformat/scte_35.c
> new file mode 100644
> index 0000000..1a01d14
> --- /dev/null
> +++ b/libavformat/scte_35.c
> @@ -0,0 +1,527 @@
> +/*
> + * SCTE 35 decoder
> + * Copyright (c) 2016 Carlos Fernandez
> + *
> + * 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
> + */
> +/*
> + * Refrence Material Used
> + *
> + * ANSI/SCTE 35 2013 (Digital Program Insertion Cueing Message for Cable)
> + *
> + * SCTE 67 2014 (Recommended Practice for SCTE 35
> + * Digital Program Insertion Cueing Message for Cable)
> + */
> +
> +
> +
> +#include "libavcodec/bytestream.h"
> +#include "libavcodec/avcodec.h"
> +#include "libavcodec/get_bits.h"
> +#include "libavutil/buffer_internal.h"
> +#include "libavutil/base64.h"
> +#include "scte_35.h"
> +
> +#define SCTE_CMD_NULL 0x00
> +#define SCTE_CMD_SCHEDULE 0x04
> +#define SCTE_CMD_INSERT 0x05
> +#define SCTE_CMD_SIGNAL 0x06
> +#define SCTE_CMD_BANDWIDTH_RESERVATION 0x07
> +
> +
> +static char* get_hls_string(struct scte_35_interface *iface, struct
> scte_35_event *event,
> + const char *filename, int out_state, int seg_count,
> int64_t pos)
> +{
> + int ret;
> + av_bprint_clear(&iface->avbstr);
> + if (out_state == EVENT_IN) {
> + av_bprintf(&iface->avbstr, "#EXT-OATCLS-SCTE35:%s\n",
> iface->pkt_base64);
> + av_bprintf(&iface->avbstr, "#EXT-X-CUE-IN\n");
> + av_bprintf(&iface->avbstr, "#EXT-X-DISCONTINUITY\n");
> + } else if (out_state == EVENT_OUT) {
> + if (event) {
> + av_bprintf(&iface->avbstr, "#EXT-OATCLS-SCTE35:%s\n",
> iface->pkt_base64);
> + if (event->duration != AV_NOPTS_VALUE) {
> + int64_t dur = ceil(((double)event->duration *
> iface->timebase.num) /iface->timebase.den);
> + av_bprintf(&iface->avbstr, "#EXT-X-CUE-OUT:%"PRIu64"\n",
> dur);
> + } else {
> + av_bprintf(&iface->avbstr, "#EXT-X-CUE-OUT\n");
> + }
> + av_bprintf(&iface->avbstr, "#EXT-X-DISCONTINUITY\n");
> + }
> + } else if (out_state == EVENT_OUT_CONT) {
> + if (event && event->duration != AV_NOPTS_VALUE) {
> + int64_t dur = ceil(((double)event->duration *
> iface->timebase.num) /iface->timebase.den);
> + int64_t elapsed_time = ceil(((double)pos *
> iface->timebase.num) /iface->timebase.den) - event->out_pts;
> + av_bprintf(&iface->avbstr, "#EXT-X-CUE-OUT-CONT:
> ElapsedTime=%"PRIu64",Duration=%"PRIu64",SCTE35=%s\n",
> + elapsed_time, dur, iface->pkt_base64);
> + } else {
> + av_bprintf(&iface->avbstr, "#EXT-X-CUE-OUT-CONT:SCTE35=%s\n",
> iface->pkt_base64);
> + }
> + }
> + if (seg_count >= 0)
> + av_bprintf(&iface->avbstr, filename, seg_count);
> + else
> + av_bprintf(&iface->avbstr, "%s", filename);
> + av_bprintf(&iface->avbstr, "\n");
> +
> + ret = av_bprint_is_complete(&iface->avbstr);
> + if (ret == 0) {
> + av_log(iface->parent, AV_LOG_DEBUG, "Out of Memory");
> + return NULL;
> + }
> +
> + av_log(iface->parent, AV_LOG_DEBUG, "%s", iface->avbstr.str);
> + return iface->avbstr.str;
> +}
> +
> +static struct scte_35_event* alloc_scte35_event(int id)
> +{
> + struct scte_35_event* event = av_malloc(sizeof(struct scte_35_event));
> + if (!event)
> + return NULL;
> +
> + event->id = id;
> + event->in_pts = AV_NOPTS_VALUE;
> + event->nearest_in_pts = AV_NOPTS_VALUE;
> + event->out_pts = AV_NOPTS_VALUE;
> + event->running = 0;
> + event->next = NULL;
> + event->prev = NULL;
> + return event;
> +}
> +
> +static void ref_scte35_event(struct scte_35_event *event)
> +{
> + event->ref_count++;
> +}
> +
> +static void unref_scte35_event(struct scte_35_event **event)
> +{
> + if (!(*event))
> + return;
> + if (!(*event)->ref_count) {
> + av_freep(event);
> + } else {
> + (*event)->ref_count--;
> + }
> +}
> +
> +static void unlink_scte35_event(struct scte_35_interface *iface, struct
> scte_35_event *event)
> +{
> + if (!event)
> + return;
> + if (!event->prev)
> + iface->event_list = event->next;
> + else
> + event->prev->next = event->next;
> + if (event->next)
> + event->next->prev = event->prev;
> + unref_scte35_event(&event);
> +}
> +
> +static struct scte_35_event* get_event_id(struct scte_35_interface
> *iface, int id)
> +{
> + struct scte_35_event *event = iface->event_list;
> + struct scte_35_event *pevent = NULL;
> +
> + while(event) {
> +
> + if (event->id == id)
> + break;
> + pevent = event;
> + event = event->next;
> + }
> + if (!event) {
> + event = alloc_scte35_event(id);
> + if (pevent)
> + pevent->next = event;
> + else
> + iface->event_list = event;
> + }
> +
> + return event;
> +}
> +
> +/**
> + * save the parsed time in ctx pts_time
> + @return length of buffer consumed
> +*/
> +static int parse_splice_time(struct scte_35_interface *iface, const
> uint8_t *buf, uint64_t *pts, int64_t pts_adjust)
> +{
> + GetBitContext gb;
> + int ret;
> + init_get_bits(&gb, buf, 40);
> + /* is time specified */
> + ret = get_bits(&gb, 1);
> + if (ret) {
> + skip_bits(&gb, 6);
> + *pts = get_bits64(&gb,33) + pts_adjust;
> + return 5;
> + } else {
> + skip_bits(&gb, 7);
> + return 1;
> + }
> +}
> +
> +static int parse_schedule_cmd(struct scte_35_interface *iface, const
> uint8_t *buf)
> +{
> + const uint8_t *sbuf = buf;
> + av_log(iface->parent, AV_LOG_DEBUG, "Schedule cmd\n");
> + return buf - sbuf;
> +}
> +/**
> + @return length of buffer used
> + */
> +static int parse_insert_cmd(struct scte_35_interface *iface,
> + const uint8_t *buf,const int len, int64_t pts_adjust, int64_t
> current_pts)
> +{
> + GetBitContext gb;
> + int ret;
> + const uint8_t *sbuf = buf;
> + int program_splice_flag;
> + int duration_flag;
> + int splice_immediate_flag;
> + int component_tag;
> + int auto_return;
> + uint16_t u_program_id;
> + uint8_t avail_num;
> + uint8_t avail_expect;
> + int inout;
> + int event_id;
> + struct scte_35_event *event;
> + char buffer[128];
> + int cancel;
> +
> +
> + av_log(iface->parent, AV_LOG_DEBUG, "%s Insert cmd\n", buffer);
> + event_id = AV_RB32(buf);
> + av_log(iface->parent, AV_LOG_DEBUG, "event_id = %x\n", event_id);
> + event = get_event_id(iface, event_id);
> + buf +=4;
> + cancel = *buf & 0x80;
> + av_log(iface->parent, AV_LOG_DEBUG, "splice_event_cancel_indicator =
> %d\n", cancel);
> + buf++;
> +
> + if (!cancel) {
> + init_get_bits(&gb, buf, 8);
> + inout = get_bits(&gb, 1);
> + program_splice_flag = get_bits(&gb, 1);
> + duration_flag = get_bits(&gb, 1);
> + splice_immediate_flag = get_bits(&gb, 1);
> + skip_bits(&gb, 4);
> +
> + } else {
> + /* Delete event only if its not already started */
> + if (!event->running) {
> + unlink_scte35_event(iface, event);
> + }
> + }
> + buf++;
> +
> +
> + av_log(iface->parent, AV_LOG_DEBUG, "out_of_network_indicator =
> %d\n", inout);
> + av_log(iface->parent, AV_LOG_DEBUG, "program_splice_flag = %d\n",
> program_splice_flag);
> + av_log(iface->parent, AV_LOG_DEBUG, "duration_flag = %d\n",
> duration_flag);
> + av_log(iface->parent, AV_LOG_DEBUG, "splice_immediate_flag = %d\n",
> splice_immediate_flag);
> +
> + if (program_splice_flag && !splice_immediate_flag) {
> + if (inout) {
> + ret = parse_splice_time(iface, buf, &event->out_pts,
> pts_adjust);
> + event->out_pts = event->out_pts * iface->timebase.num /
> iface->timebase.den;
> + } else {
> + ret = parse_splice_time(iface, buf, &event->in_pts,
> pts_adjust);
> + event->in_pts = event->in_pts * iface->timebase.num /
> iface->timebase.den;
> + }
> +
> + buf += ret;
> + } else if (program_splice_flag && splice_immediate_flag) {
> + if (inout)
> + event->out_pts = current_pts * iface->timebase.num /
> iface->timebase.den;
> + else
> + event->in_pts = current_pts * iface->timebase.num /
> iface->timebase.den;
> + }
> + if (program_splice_flag == 0) {
> + int comp_cnt = *buf++;
> + int i;
> + av_log(iface->parent, AV_LOG_DEBUG, "component_count = %d\n",
> comp_cnt);
> + for (i = 0; i < comp_cnt; i++) {
> + component_tag = *buf++;
> + av_log(iface->parent, AV_LOG_DEBUG, "component_tag = %d\n",
> component_tag);
> + if (splice_immediate_flag) {
> + if (inout)
> + ret = parse_splice_time(iface, buf, &event->in_pts,
> pts_adjust);
> + else
> + ret = parse_splice_time(iface, buf, &event->out_pts,
> pts_adjust);
> + buf += ret;
> + }
> + }
> + }
> + if (duration_flag) {
> + init_get_bits(&gb, buf, 40);
> + auto_return = get_bits(&gb, 1);
> + av_log(iface->parent, AV_LOG_DEBUG, "autoreturn = %d\n",
> auto_return);
> + skip_bits(&gb, 6);
> + event->duration = get_bits64(&gb,33) + pts_adjust;
> + buf += 5;
> + }
> + u_program_id = AV_RB16(buf);
> + av_log(iface->parent, AV_LOG_DEBUG, "u_program_id = %hd\n",
> u_program_id);
> + buf += 2;
> + avail_num = *buf++;
> + av_log(iface->parent, AV_LOG_DEBUG, "avail_num = %hhd\n", avail_num);
> + avail_expect = *buf++;
> + av_log(iface->parent, AV_LOG_DEBUG, "avail_expect = %hhd\n",
> avail_expect);
> +
> + return buf - sbuf;
> +}
> +static int parse_time_signal_cmd(struct scte_35_interface *iface, const
> uint8_t *buf)
> +{
> + const uint8_t *sbuf = buf;
> + av_log(iface->parent, AV_LOG_DEBUG, "Time Signal cmd\n");
> + return buf - sbuf;
> +}
> +static int parse_bandwidth_reservation_cmd(struct scte_35_interface
> *iface, const uint8_t *buf)
> +{
> + const uint8_t *sbuf = buf;
> + av_log(iface->parent, AV_LOG_DEBUG, "Band Width reservation cmd\n");
> + return buf - sbuf;
> +}
> +
> +int ff_parse_scte35_pkt(struct scte_35_interface *iface, const AVPacket
> *avpkt)
> +{
> + const uint8_t *buf = avpkt->data;
> + int section_length;
> + int cmd_length;
> + uint8_t cmd_type;
> + int16_t tier;
> + GetBitContext gb;
> + int ret;
> + int64_t pts_adjust;
> +
> + if (!buf)
> + return AVERROR_EOF;
> +
> +
> + /* check table id */
> + if (*buf != 0xfc)
> + av_log(iface->parent, AV_LOG_ERROR, "Invalid SCTE packet\n");
> +
> +
> + init_get_bits(&gb, buf + 1, 104);
> +
> + /* section_syntax_indicator should be 0 */
> + ret = get_bits(&gb,1);
> + if (ret)
> + av_log(iface->parent, AV_LOG_DEBUG, "Section indicator should be
> 0, since MPEG short sections are to be used.\n");
> +
> + /* private indicator */
> + ret = get_bits(&gb,1);
> + if (ret)
> + av_log(iface->parent, AV_LOG_DEBUG, "corrupt packet\n");
> +
> + skip_bits(&gb,2);
> +
> + /* section length may be there */
> + section_length = get_bits(&gb,12);
> + if (section_length > 4093)
> + if (ret) {
> + av_log(iface->parent, AV_LOG_ERROR, "Invalid length of
> section\n");
> + return AVERROR_INVALIDDATA;
> + }
> +
> + av_base64_encode(iface->pkt_base64, AV_BASE64_SIZE(section_length +
> 3), buf, section_length + 3);
> +
> + /* protocol version */
> + skip_bits(&gb,8);
> +
> + ret = get_bits(&gb,1);
> + if (ret) {
> + av_log(iface->parent, AV_LOG_ERROR, "Encrytion not yet
> supported\n");
> + return AVERROR_PATCHWELCOME;
> + }
> + /* encryption algo */
> + skip_bits(&gb,6);
> +
> + pts_adjust = get_bits64(&gb, 33);
> +
> + /* cw_index: used in encryption */
> + skip_bits(&gb,8);
> +
> +
> + /* tier */
> + tier = get_bits(&gb,12);
> + if ((tier & 0xfff) == 0xfff)
> + tier = -1;
> +
> + cmd_length = get_bits(&gb,12);
> + if (cmd_length == 0xfff) {
> + /* Setting max limit to cmd_len so it does not cross memory
> barrier */
> + cmd_length = section_length - 17;
> + } else if (cmd_length != 0xfff && (cmd_length > (section_length - 17)
> ) ) {
> + av_log(iface->parent, AV_LOG_ERROR, "Command length %d
> invalid\n", cmd_length);
> + return AVERROR_INVALIDDATA;
> + }
> +
> + cmd_type = get_bits(&gb,8);
> + switch(cmd_type) {
> + case SCTE_CMD_NULL:
> + av_log(iface->parent, AV_LOG_DEBUG, "SCTE-35 Ping Recieved");
> + break;
> + case SCTE_CMD_SCHEDULE:
> + ret = parse_schedule_cmd(iface, buf + 14);
> + break;
> + case SCTE_CMD_INSERT:
> + ret = parse_insert_cmd(iface, buf + 14, cmd_length, pts_adjust,
> avpkt->pts);
> + break;
> + case SCTE_CMD_SIGNAL:
> + ret = parse_time_signal_cmd(iface, buf + 14);
> + break;
> + case SCTE_CMD_BANDWIDTH_RESERVATION:
> + ret = parse_bandwidth_reservation_cmd(iface, buf + 14);
> + break;
> + default:
> + break;
> + /* reserved yet */
> + }
> + if (ret < 0)
> + goto fail;
> + buf += ret;
> +
> +fail:
> + return ret;
> +}
> +
> +/*
> + * return event, if there is any event whose starting time aka out_pts is
> less then
> + * current pts. This condition also means that event starting time has
> already been passed.
> + * This function will look for event in events list which resides inside
> iface.
> + */
> +static struct scte_35_event* get_event_ciel_out(struct scte_35_interface
> *iface, uint64_t pts)
> +{
> + struct scte_35_event *event = iface->event_list;
> + while(event) {
> + if (!event->running && event->out_pts < pts) {
> + iface->event_state = EVENT_OUT;
> + break;
> + }
> + event = event->next;
> + }
> + return event;
> +}
> +
> +/*
> + * return event, if current event is in running state
> + * and check that in_pts is less then current pts.
> + * Event from this function specify commerial ends and
> + * mainstream should be coupled in.
> + * This event is generally last event to be consumed.
> + */
> +static struct scte_35_event* get_event_floor_in(struct scte_35_interface
> *iface, uint64_t pts)
> +{
> + struct scte_35_event *event = iface->event_list;
> + struct scte_35_event *sevent = NULL;
> + while(event) {
> + if (event->in_pts != AV_NOPTS_VALUE && event->in_pts < pts &&
> + (event->nearest_in_pts == AV_NOPTS_VALUE || pts <=
> event->nearest_in_pts) ) {
> + event->nearest_in_pts = pts;
> + unlink_scte35_event(iface, event);
> + /* send in_event only when that event was in running state */
> + if (event->running) {
> + iface->event_state = EVENT_IN;
> + sevent = event;
> + }
> + }
> + event = event->next;
> + }
> + return sevent;
> +}
> +
> +
> +/*
> + * If there is no running event, then search for an event which have
> + * the pts matching to current pts. otherwise only give event when
> + * its time to end the commercial.
> + * if we have some event to be presented at this video then cache it
> + * for later use.
> + */
> +static void update_video_pts(struct scte_35_interface *iface, uint64_t
> pts)
> +{
> + struct scte_35_event *event = NULL;
> + if (iface->event_state == EVENT_NONE) {
> + event = get_event_ciel_out(iface, pts);
> + if (event)
> + event->running = 1;
> + } else {
> + event = get_event_floor_in(iface, pts);
> + }
> + if (event)
> + iface->current_event = event;
> +}
> +
> +/*
> + * update the state of scte-35 parser
> + * return current event
> + */
> +static struct scte_35_event* update_event_state(struct scte_35_interface
> *iface)
> +{
> +
> + struct scte_35_event* event = iface->current_event;
> + if (iface->prev_event_state == EVENT_IN)
> + iface->event_state = EVENT_NONE;
> + else if (iface->prev_event_state == EVENT_OUT)
> + iface->event_state = EVENT_OUT_CONT;
> +
> + if (iface->event_state == EVENT_NONE)
> + iface->current_event = NULL;
> +
> + iface->prev_event_state = iface->event_state;
> + return event;
> +}
> +
> +
> +/*
> + * Allocate scte_35 parser
> + * using function pointer so that this module reveals least interface
> + * to API uses
> + */
> +struct scte_35_interface* ff_alloc_scte35_parser(void *parent, AVRational
> timebase)
> +{
> + struct scte_35_interface* iface = av_mallocz(sizeof(struct
> scte_35_interface));
> + if (!iface)
> + return NULL;
> +
> + iface->parent = parent;
> + iface->timebase = timebase;
> + iface->update_video_pts = update_video_pts;
> + iface->update_event_state = update_event_state;
> + av_bprint_init(&iface->avbstr, 0, AV_BPRINT_SIZE_UNLIMITED);
> + iface->get_hls_string = get_hls_string;
> + iface->unref_scte35_event = unref_scte35_event;
> + iface->ref_scte35_event = ref_scte35_event;
> + iface->event_state = EVENT_NONE;
> + iface->prev_event_state = EVENT_NONE;
> + return iface;
> +}
> +
> +void ff_delete_scte35_parser(struct scte_35_interface* iface)
> +{
> + if (!iface)
> + return;
> + av_bprint_finalize(&iface->avbstr, NULL);
> + av_freep(&iface);
> +}
> diff --git a/libavformat/scte_35.h b/libavformat/scte_35.h
> new file mode 100644
> index 0000000..cac49ea
> --- /dev/null
> +++ b/libavformat/scte_35.h
> @@ -0,0 +1,86 @@
> +/*
> + * SCTE-35 parser
> + * Copyright (c) 2016 Carlos Fernandez
> + *
> + * 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 AVFORMAT_SCTE_35_H
> +#define AVFORMAT_SCTE_35_H
> +
> +#include "libavutil/bprint.h"
> +
> +struct scte_35_event {
> + /* ID given for each seprate event */
> + int32_t id;
> + /* pts specify time when event starts */
> + uint64_t in_pts;
> + uint64_t nearest_in_pts;
> + /* pts specify ehen events end */
> + uint64_t out_pts;
> + /* duration of the event */
> + int64_t duration;
> + int64_t start_pos;
> + int running;
> + int ref_count;
> + /* to traverse the list of events */
> + struct scte_35_event *next;
> + struct scte_35_event *prev;
> +};
> +
> +enum event_state {
> + /* NO event */
> + EVENT_NONE,
> + /* Commercials need to end */
> + EVENT_IN,
> + /* Commercials can start from here */
> + EVENT_OUT,
> + /* commercial can continue */
> + EVENT_OUT_CONT,
> +};
> +
> +struct scte_35_interface {
> + /* contain all the events */
> + struct scte_35_event *event_list;
> + /* state of current event */
> + enum event_state event_state;
> + /* time base of pts used in parser */
> + AVRational timebase;
> + struct scte_35_event *current_event;
> + /* saved previous state to correctly transition
> + the event state */
> + int prev_event_state;
> + //TODO use AV_BASE64_SIZE to dynamically allocate the array
> + char pkt_base64[1024];
> + /* keep context of its parent for log */
> + void *parent;
> + /* general purpose str */
> + AVBPrint avbstr;
> +
> + void (*update_video_pts)(struct scte_35_interface *iface, uint64_t
> pts);
> + struct scte_35_event* (*update_event_state)(struct scte_35_interface
> *iface);
> + char* (*get_hls_string)(struct scte_35_interface *iface, struct
> scte_35_event *event,
> + const char *adv_filename, int out_state, int seg_count,
> int64_t pos);
> +
> + void (*unref_scte35_event)(struct scte_35_event **event);
> + void (*ref_scte35_event)(struct scte_35_event *event);
> +};
> +
> +int ff_parse_scte35_pkt(struct scte_35_interface *iface, const AVPacket
> *avpkt);
> +
> +struct scte_35_interface* ff_alloc_scte35_parser(void *parent, AVRational
> timebase);
> +void ff_delete_scte35_parser(struct scte_35_interface* iface);
> +#endif
> --
> 2.7.4
>
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