Example #1
0
static void decode(struct sd *sd, struct demux_packet *packet)
{
    struct sd_ass_priv *ctx = sd->priv;
    ASS_Track *track = ctx->ass_track;
    if (ctx->converter) {
        if (!sd->opts->sub_clear_on_seek && packet->pos >= 0 &&
            check_packet_seen(sd, packet->pos))
            return;
        if (packet->duration < 0) {
            if (!ctx->duration_unknown) {
                MP_WARN(sd, "Subtitle with unknown duration.\n");
                ctx->duration_unknown = true;
            }
            packet->duration = UNKNOWN_DURATION;
        }
        char **r = lavc_conv_decode(ctx->converter, packet);
        for (int n = 0; r && r[n]; n++)
            ass_process_data(track, r[n], strlen(r[n]));
        if (ctx->duration_unknown) {
            for (int n = 0; n < track->n_events - 1; n++) {
                if (track->events[n].Duration == UNKNOWN_DURATION * 1000) {
                    track->events[n].Duration = track->events[n + 1].Start -
                                                track->events[n].Start;
                }
            }
        }
    } else {
        // Note that for this packet format, libass has an internal mechanism
        // for discarding duplicate (already seen) packets.
        ass_process_chunk(track, packet->buffer, packet->len,
                          llrint(packet->pts * 1000),
                          llrint(packet->duration * 1000));
    }
}
Example #2
0
static void libass_push_packet(csri_inst *inst,
	const void *packet, size_t packetlen,
	double pts_start, double pts_end)
{
	ass_process_chunk(inst->ass_track, (void *)packet, packetlen,
		(int)(pts_start * 1000), (int)((pts_end - pts_start) * 1000));
}
Example #3
0
static void decode(struct sd *sd, struct demux_packet *packet)
{
    struct sd_ass_priv *ctx = sd->priv;
    ASS_Track *track = ctx->ass_track;
    long long ipts = packet->pts * 1000 + 0.5;
    long long iduration = packet->duration * 1000 + 0.5;
    if (strcmp(sd->codec, "ass") == 0) {
        ass_process_chunk(track, packet->buffer, packet->len, ipts, iduration);
        return;
    } else if (strcmp(sd->codec, "ssa") == 0) {
        // broken ffmpeg ASS packet format
        ctx->flush_on_seek = true;
        ass_process_data(track, packet->buffer, packet->len);
        return;
    }

    // plaintext subs
    if (packet->pts == MP_NOPTS_VALUE) {
        MP_WARN(sd, "Subtitle without pts, ignored\n");
        return;
    }
    if (ctx->extend_event >= 0 && ctx->extend_event < track->n_events) {
        ASS_Event *event = &track->events[ctx->extend_event];
        if (event->Start <= ipts)
            event->Duration = ipts - event->Start;
        ctx->extend_event = -1;
    }

    unsigned char *text = packet->buffer;
    if (!sd->no_remove_duplicates) {
        for (int i = 0; i < track->n_events; i++) {
            if (track->events[i].Start == ipts
                && (track->events[i].Duration == iduration)
                && strcmp(track->events[i].Text, text) == 0)
                return;   // We've already added this subtitle
        }
    }
    int eid = ass_alloc_event(track);
    ASS_Event *event = track->events + eid;

    if (packet->duration == 0) {
        MP_WARN(sd, "Subtitle without duration or "
                "duration set to 0 at pts %f.\n", packet->pts);
    }
    if (packet->duration < 0) {
        // Assume unknown duration. The FFmpeg API is very unclear about this.
        MP_WARN(sd, "Assuming subtitle without duration at pts %f\n", packet->pts);
        // _If_ there's a next subtitle, the duration will be adjusted again.
        // If not, show it forever.
        iduration = INT_MAX;
        ctx->extend_event = eid;
    }

    event->Start = ipts;
    event->Duration = iduration;
    event->Style = track->default_style;
    event->Text = strdup(text);
}
Example #4
0
static void decode(struct sh_sub *sh, struct osd_state *osd, void *data,
                   int data_len, double pts, double duration)
{
    unsigned char *text = data;
    struct sd_ass_priv *ctx = sh->context;
    ASS_Track *track = ctx->ass_track;

    if (sh->type == 'a') { // ssa/ass subs
        ass_process_chunk(track, data, data_len,
                          (long long)(pts*1000 + 0.5),
                          (long long)(duration*1000 + 0.5));
        return;
    }
    // plaintext subs
    if (pts == MP_NOPTS_VALUE) {
        mp_msg(MSGT_SUBREADER, MSGL_WARN, "Subtitle without pts, ignored\n");
        return;
    }
    long long ipts = pts * 1000 + 0.5;
    long long iduration = duration * 1000 + 0.5;
    if (ctx->incomplete_event) {
        ctx->incomplete_event = false;
        ASS_Event *event = track->events + track->n_events - 1;
        if (ipts <= event->Start)
            free_last_event(track);
        else
            event->Duration = ipts - event->Start;
    }
    // Note: we rely on there being guaranteed 0 bytes after data packets
    int len = strlen(text);
    if (len < 5) {
        // Some tracks use a whitespace (but not empty) packet to mark end
        // of previous subtitle.
        for (int i = 0; i < len; i++)
            if (!strchr(" \f\n\r\t\v", text[i]))
                goto not_all_whitespace;
        return;
    }
 not_all_whitespace:;
    char buf[500];
    subassconvert_subrip(text, buf, sizeof(buf));
    for (int i = 0; i < track->n_events; i++)
        if (track->events[i].Start == ipts
            && (duration <= 0 || track->events[i].Duration == iduration)
            && strcmp(track->events[i].Text, buf) == 0)
            return;   // We've already added this subtitle
    if (duration <= 0) {
        iduration = 10000;
        ctx->incomplete_event = true;
    }
    int eid = ass_alloc_event(track);
    ASS_Event *event = track->events + eid;
    event->Start = ipts;
    event->Duration = iduration;
    event->Style = track->default_style;
    event->Text = strdup(buf);
}
Example #5
0
bool CDVDSubtitlesLibass::DecodeDemuxPkt(const char* data, int size, double start, double duration)
{
  CSingleLock lock(m_section);
  if(!m_track)
  {
    CLog::Log(LOGERROR, "CDVDSubtitlesLibass: No SSA header found.");
    return false;
  }

  //! @bug libass isn't const correct
  ass_process_chunk(m_track, const_cast<char*>(data), size, DVD_TIME_TO_MSEC(start), DVD_TIME_TO_MSEC(duration));
  return true;
}
Example #6
0
File: sd_ass.c Project: ThreeGe/mpv
static void decode(struct sd *sd, struct demux_packet *packet)
{
    struct sd_ass_priv *ctx = sd->priv;
    ASS_Track *track = ctx->ass_track;
    if (ctx->converter) {
        if (!sd->opts->sub_clear_on_seek && check_packet_seen(sd, packet->pos))
            return;
        char **r = lavc_conv_decode(ctx->converter, packet);
        for (int n = 0; r && r[n]; n++)
            ass_process_data(track, r[n], strlen(r[n]));
    } else {
        // Note that for this packet format, libass has an internal mechanism
        // for discarding duplicate (already seen) packets.
        ass_process_chunk(track, packet->buffer, packet->len,
                          lrint(packet->pts * 1000),
                          lrint(packet->duration * 1000));
    }
}
Example #7
0
File: sd_ass.c Project: agiz/mpv
static void decode(struct sd *sd, struct demux_packet *packet)
{
    struct sd_ass_priv *ctx = sd->priv;
    ASS_Track *track = ctx->ass_track;
    long long ipts = packet->pts * 1000 + 0.5;
    long long iduration = packet->duration * 1000 + 0.5;
    if (strcmp(sd->codec, "ass") == 0) {
        ass_process_chunk(track, packet->buffer, packet->len, ipts, iduration);
        return;
    } else if (strcmp(sd->codec, "ssa") == 0) {
        // broken ffmpeg ASS packet format
        ctx->flush_on_seek = true;
        ass_process_data(track, packet->buffer, packet->len);
        return;
    }
    // plaintext subs
    if (packet->pts == MP_NOPTS_VALUE) {
        mp_msg(MSGT_SUBREADER, MSGL_WARN, "Subtitle without pts, ignored\n");
        return;
    }
    if (packet->duration <= 0) {
        mp_msg(MSGT_SUBREADER, MSGL_WARN, "Subtitle without duration or "
               "duration set to 0 at pts %f, ignored\n", packet->pts);
        return;
    }
    unsigned char *text = packet->buffer;
    if (!sd->no_remove_duplicates) {
        for (int i = 0; i < track->n_events; i++) {
            if (track->events[i].Start == ipts
                && (track->events[i].Duration == iduration)
                && strcmp(track->events[i].Text, text) == 0)
                return;   // We've already added this subtitle
        }
    }
    int eid = ass_alloc_event(track);
    ASS_Event *event = track->events + eid;
    event->Start = ipts;
    event->Duration = iduration;
    event->Style = track->default_style;
    event->Text = strdup(text);
}
Example #8
0
/****************************************************************************
 * DecodeBlock:
 ****************************************************************************/
static subpicture_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
{
    decoder_sys_t *p_sys = p_dec->p_sys;

    subpicture_t *p_spu = NULL;
    block_t *p_block;

    if( !pp_block || *pp_block == NULL )
        return NULL;

    p_block = *pp_block;
    *pp_block = NULL;

    if( p_block->i_flags & BLOCK_FLAG_CORRUPTED )
    {
        Flush( p_dec );
        block_Release( p_block );
        return NULL;
    }

    if( p_block->i_buffer == 0 || p_block->p_buffer[0] == '\0' )
    {
        block_Release( p_block );
        return NULL;
    }

    subpicture_updater_sys_t *p_spu_sys = malloc( sizeof(*p_spu_sys) );
    if( !p_spu_sys )
    {
        block_Release( p_block );
        return NULL;
    }

    subpicture_updater_t updater = {
        .pf_validate = SubpictureValidate,
        .pf_update   = SubpictureUpdate,
        .pf_destroy  = SubpictureDestroy,
        .p_sys       = p_spu_sys,
    };
    p_spu = decoder_NewSubpicture( p_dec, &updater );
    if( !p_spu )
    {
        msg_Warn( p_dec, "can't get spu buffer" );
        free( p_spu_sys );
        block_Release( p_block );
        return NULL;
    }

    p_spu_sys->p_img = NULL;
    p_spu_sys->p_dec_sys = p_sys;
    p_spu_sys->i_subs_len = p_block->i_buffer;
    p_spu_sys->p_subs_data = malloc( p_block->i_buffer );
    p_spu_sys->i_pts = p_block->i_pts;
    if( !p_spu_sys->p_subs_data )
    {
        subpicture_Delete( p_spu );
        block_Release( p_block );
        return NULL;
    }
    memcpy( p_spu_sys->p_subs_data, p_block->p_buffer,
            p_block->i_buffer );

    p_spu->i_start = p_block->i_pts;
    p_spu->i_stop = __MAX( p_sys->i_max_stop, p_block->i_pts + p_block->i_length );
    p_spu->b_ephemer = true;
    p_spu->b_absolute = true;

    p_sys->i_max_stop = p_spu->i_stop;

    vlc_mutex_lock( &p_sys->lock );
    if( p_sys->p_track )
    {
        ass_process_chunk( p_sys->p_track, p_spu_sys->p_subs_data, p_spu_sys->i_subs_len,
                           p_block->i_pts / 1000, p_block->i_length / 1000 );
    }
    vlc_mutex_unlock( &p_sys->lock );

    DecSysHold( p_sys ); /* Keep a reference for the returned subpicture */

    block_Release( p_block );

    return p_spu;
}
Example #9
0
void update_subtitles(sh_video_t *sh_video, double refpts, demux_stream_t *d_dvdsub, int reset)
{
    double curpts = refpts - sub_delay;
    unsigned char *packet=NULL;
    int len;
    int type = d_dvdsub->sh ? ((sh_sub_t *)d_dvdsub->sh)->type : 'v';
    static subtitle subs;
    if (reset) {
        sub_clear_text(&subs, MP_NOPTS_VALUE);
        if (vo_sub) {
            set_osd_subtitle(NULL);
        }
        if (vo_spudec) {
            spudec_reset(vo_spudec);
            vo_osd_changed(OSDTYPE_SPU);
        }
#ifdef CONFIG_FFMPEG
        if (is_av_sub(type))
            reset_avsub(d_dvdsub->sh);
#endif
    }
    // find sub
    if (subdata) {
        if (sub_fps==0) sub_fps = sh_video ? sh_video->fps : 25;
        current_module = "find_sub";
        if (refpts > sub_last_pts || refpts < sub_last_pts-1.0) {
            find_sub(subdata, curpts *
                     (subdata->sub_uses_time ? 100. : sub_fps));
            if (vo_sub) vo_sub_last = vo_sub;
            // FIXME! frame counter...
            sub_last_pts = refpts;
        }
    }

    // DVD sub:
    if (vo_config_count &&
        (vobsub_id >= 0 || type == 'v')) {
        int timestamp;
        current_module = "spudec";
        /* Get a sub packet from the DVD or a vobsub */
        while(1) {
            // Vobsub
            len = 0;
            if (vo_vobsub) {
                if (curpts >= 0) {
                    len = vobsub_get_packet(vo_vobsub, curpts,
                                            (void**)&packet, &timestamp);
                    if (len > 0) {
                        mp_dbg(MSGT_CPLAYER,MSGL_V,"\rVOB sub: len=%d v_pts=%5.3f v_timer=%5.3f sub=%5.3f ts=%d \n",len,refpts,sh_video->timer,timestamp / 90000.0,timestamp);
                    }
                }
            } else {
                // DVD sub
                len = ds_get_packet_sub(d_dvdsub, (unsigned char**)&packet, NULL, NULL);
                if (len > 0) {
                    // XXX This is wrong, sh_video->pts can be arbitrarily
                    // much behind demuxing position. Unfortunately using
                    // d_video->pts which would have been the simplest
                    // improvement doesn't work because mpeg specific hacks
                    // in video.c set d_video->pts to 0.
                    float x = d_dvdsub->pts - refpts;
                    if (x > -20 && x < 20) // prevent missing subs on pts reset
                        timestamp = 90000*d_dvdsub->pts;
                    else timestamp = 90000*curpts;
                    mp_dbg(MSGT_CPLAYER, MSGL_V, "\rDVD sub: len=%d  "
                           "v_pts=%5.3f  s_pts=%5.3f  ts=%d \n", len,
                           refpts, d_dvdsub->pts, timestamp);
                }
            }
            if (len<=0 || !packet) break;
            // create it only here, since with some broken demuxers we might
            // type = v but no DVD sub and we currently do not change the
            // "original frame size" ever after init, leading to wrong-sized
            // PGS subtitles.
            if (!vo_spudec)
                vo_spudec = spudec_new(NULL);
            if (vo_vobsub || timestamp >= 0)
                spudec_assemble(vo_spudec, packet, len, timestamp);
        }
    } else if (is_text_sub(type) || is_av_sub(type) || type == 'd') {
        int orig_type = type;
        double endpts;
        if (type == 'd' && !d_dvdsub->demuxer->teletext) {
            tt_stream_props tsp = {0};
            void *ptr = &tsp;
            if (teletext_control(NULL, TV_VBI_CONTROL_START, &ptr) == VBI_CONTROL_TRUE)
                d_dvdsub->demuxer->teletext = ptr;
        }
        if (d_dvdsub->non_interleaved)
            ds_get_next_pts(d_dvdsub);
        while (1) {
            double subpts = curpts;
            type = orig_type;
            len = ds_get_packet_sub(d_dvdsub, &packet, &subpts, &endpts);
            if (len < 0)
                break;
            if (is_av_sub(type)) {
#ifdef CONFIG_FFMPEG
                type = decode_avsub(d_dvdsub->sh, &packet, &len, &subpts, &endpts);
                if (type <= 0)
#endif
                    continue;
            }
            if (type == 'm') {
                if (len < 2) continue;
                len = FFMIN(len - 2, AV_RB16(packet));
                packet += 2;
            }
            if (type == 'd') {
                if (d_dvdsub->demuxer->teletext) {
                    uint8_t *p = packet;
                    p++;
                    len--;
                    while (len >= 46) {
                        int sublen = p[1];
                        if (p[0] == 2 || p[0] == 3)
                            teletext_control(d_dvdsub->demuxer->teletext,
                                TV_VBI_CONTROL_DECODE_DVB, p + 2);
                        p   += sublen + 2;
                        len -= sublen + 2;
                    }
                }
                continue;
            }
#ifdef CONFIG_ASS
            if (ass_enabled) {
                sh_sub_t* sh = d_dvdsub->sh;
                ass_track = sh ? sh->ass_track : NULL;
                if (!ass_track) continue;
                if (type == 'a') { // ssa/ass subs with libass
                    if (len > 10 && memcmp(packet, "Dialogue: ", 10) == 0)
                        ass_process_data(ass_track, packet, len);
                    else
                        ass_process_chunk(ass_track, packet, len,
                                          (long long)(subpts*1000 + 0.5),
                                          (long long)((endpts-subpts)*1000 + 0.5));
                } else { // plaintext subs with libass
                    if (subpts != MP_NOPTS_VALUE) {
                        subtitle tmp_subs = {0};
                        if (endpts == MP_NOPTS_VALUE) endpts = subpts + 3;
                        sub_add_text(&tmp_subs, packet, len, endpts, 0);
                        tmp_subs.start = subpts * 100;
                        tmp_subs.end = endpts * 100;
                        ass_process_subtitle(ass_track, &tmp_subs);
                        sub_clear_text(&tmp_subs, MP_NOPTS_VALUE);
                    }
                }
                continue;
            }
#endif
            if (subpts != MP_NOPTS_VALUE) {
                if (endpts == MP_NOPTS_VALUE)
                    sub_clear_text(&subs, MP_NOPTS_VALUE);
                if (type == 'a') { // ssa/ass subs without libass => convert to plaintext
                    int i;
                    unsigned char* p = packet;
                    int skip_commas = 8;
                    if (len > 10 && memcmp(packet, "Dialogue: ", 10) == 0)
                        skip_commas = 9;
                    for (i=0; i < skip_commas && *p != '\0'; p++)
                        if (*p == ',')
                            i++;
                    if (*p == '\0')  /* Broken line? */
                        continue;
                    len -= p - packet;
                    packet = p;
                }
                sub_add_text(&subs, packet, len, endpts, 1);
                set_osd_subtitle(&subs);
            }
            if (d_dvdsub->non_interleaved)
                ds_get_next_pts(d_dvdsub);
        }
        if (sub_clear_text(&subs, curpts))
            set_osd_subtitle(&subs);
    }
    if (vo_spudec) {
        spudec_heartbeat(vo_spudec, 90000*curpts);
        if (spudec_changed(vo_spudec))
            vo_osd_changed(OSDTYPE_SPU);
    }

    current_module=NULL;
}
Example #10
0
static av_cold int init_subtitles(AVFilterContext *ctx)
{
    int j, ret, sid;
    int k = 0;
    AVDictionary *codec_opts = NULL;
    AVFormatContext *fmt = NULL;
    AVCodecContext *dec_ctx = NULL;
    AVCodec *dec = NULL;
    const AVCodecDescriptor *dec_desc;
    AVStream *st;
    AVPacket pkt;
    AssContext *ass = ctx->priv;

    /* Init libass */
    ret = init(ctx);
    if (ret < 0)
        return ret;
    ass->track = ass_new_track(ass->library);
    if (!ass->track) {
        av_log(ctx, AV_LOG_ERROR, "Could not create a libass track\n");
        return AVERROR(EINVAL);
    }

    /* Open subtitles file */
    ret = avformat_open_input(&fmt, ass->filename, NULL, NULL);
    if (ret < 0) {
        av_log(ctx, AV_LOG_ERROR, "Unable to open %s\n", ass->filename);
        goto end;
    }
    ret = avformat_find_stream_info(fmt, NULL);
    if (ret < 0)
        goto end;

    /* Locate subtitles stream */
    if (ass->stream_index < 0)
        ret = av_find_best_stream(fmt, AVMEDIA_TYPE_SUBTITLE, -1, -1, NULL, 0);
    else {
        ret = -1;
        if (ass->stream_index < fmt->nb_streams) {
            for (j = 0; j < fmt->nb_streams; j++) {
                if (fmt->streams[j]->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE) {
                    if (ass->stream_index == k) {
                        ret = j;
                        break;
                    }
                    k++;
                }
            }
        }
    }

    if (ret < 0) {
        av_log(ctx, AV_LOG_ERROR, "Unable to locate subtitle stream in %s\n",
               ass->filename);
        goto end;
    }
    sid = ret;
    st = fmt->streams[sid];

    /* Load attached fonts */
    for (j = 0; j < fmt->nb_streams; j++) {
        AVStream *st = fmt->streams[j];
        if (st->codecpar->codec_type == AVMEDIA_TYPE_ATTACHMENT &&
            attachment_is_font(st)) {
            const AVDictionaryEntry *tag = NULL;
            tag = av_dict_get(st->metadata, "filename", NULL,
                              AV_DICT_MATCH_CASE);

            if (tag) {
                av_log(ctx, AV_LOG_DEBUG, "Loading attached font: %s\n",
                       tag->value);
                ass_add_font(ass->library, tag->value,
                             st->codecpar->extradata,
                             st->codecpar->extradata_size);
            } else {
                av_log(ctx, AV_LOG_WARNING,
                       "Font attachment has no filename, ignored.\n");
            }
        }
    }

    /* Initialize fonts */
    ass_set_fonts(ass->renderer, NULL, NULL, 1, NULL, 1);

    /* Open decoder */
    dec = avcodec_find_decoder(st->codecpar->codec_id);
    if (!dec) {
        av_log(ctx, AV_LOG_ERROR, "Failed to find subtitle codec %s\n",
               avcodec_get_name(st->codecpar->codec_id));
        return AVERROR(EINVAL);
    }
    dec_desc = avcodec_descriptor_get(st->codecpar->codec_id);
    if (dec_desc && !(dec_desc->props & AV_CODEC_PROP_TEXT_SUB)) {
        av_log(ctx, AV_LOG_ERROR,
               "Only text based subtitles are currently supported\n");
        return AVERROR_PATCHWELCOME;
    }
    if (ass->charenc)
        av_dict_set(&codec_opts, "sub_charenc", ass->charenc, 0);
    if (LIBAVCODEC_VERSION_INT >= AV_VERSION_INT(57,26,100))
        av_dict_set(&codec_opts, "sub_text_format", "ass", 0);

    dec_ctx = avcodec_alloc_context3(dec);
    if (!dec_ctx)
        return AVERROR(ENOMEM);

    ret = avcodec_parameters_to_context(dec_ctx, st->codecpar);
    if (ret < 0)
        goto end;

    /*
     * This is required by the decoding process in order to rescale the
     * timestamps: in the current API the decoded subtitles have their pts
     * expressed in AV_TIME_BASE, and thus the lavc internals need to know the
     * stream time base in order to achieve the rescaling.
     *
     * That API is old and needs to be reworked to match behaviour with A/V.
     */
    av_codec_set_pkt_timebase(dec_ctx, st->time_base);

    ret = avcodec_open2(dec_ctx, NULL, &codec_opts);
    if (ret < 0)
        goto end;

    if (ass->force_style) {
        char **list = NULL;
        char *temp = NULL;
        char *ptr = av_strtok(ass->force_style, ",", &temp);
        int i = 0;
        while (ptr) {
            av_dynarray_add(&list, &i, ptr);
            if (!list) {
                ret = AVERROR(ENOMEM);
                goto end;
            }
            ptr = av_strtok(NULL, ",", &temp);
        }
        av_dynarray_add(&list, &i, NULL);
        if (!list) {
            ret = AVERROR(ENOMEM);
            goto end;
        }
        ass_set_style_overrides(ass->library, list);
        av_free(list);
    }
    /* Decode subtitles and push them into the renderer (libass) */
    if (dec_ctx->subtitle_header)
        ass_process_codec_private(ass->track,
                                  dec_ctx->subtitle_header,
                                  dec_ctx->subtitle_header_size);
    av_init_packet(&pkt);
    pkt.data = NULL;
    pkt.size = 0;
    while (av_read_frame(fmt, &pkt) >= 0) {
        int i, got_subtitle;
        AVSubtitle sub = {0};

        if (pkt.stream_index == sid) {
            ret = avcodec_decode_subtitle2(dec_ctx, &sub, &got_subtitle, &pkt);
            if (ret < 0) {
                av_log(ctx, AV_LOG_WARNING, "Error decoding: %s (ignored)\n",
                       av_err2str(ret));
            } else if (got_subtitle) {
                const int64_t start_time = av_rescale_q(sub.pts, AV_TIME_BASE_Q, av_make_q(1, 1000));
                const int64_t duration   = sub.end_display_time;
                for (i = 0; i < sub.num_rects; i++) {
                    char *ass_line = sub.rects[i]->ass;
                    if (!ass_line)
                        break;
                    if (LIBAVCODEC_VERSION_INT < AV_VERSION_INT(57,25,100))
                        ass_process_data(ass->track, ass_line, strlen(ass_line));
                    else
                        ass_process_chunk(ass->track, ass_line, strlen(ass_line),
                                          start_time, duration);
                }
            }
        }
        av_packet_unref(&pkt);
        avsubtitle_free(&sub);
    }

end:
    av_dict_free(&codec_opts);
    avcodec_close(dec_ctx);
    avcodec_free_context(&dec_ctx);
    avformat_close_input(&fmt);
    return ret;
}