@@ -358,8 +358,14 @@ static av_cold int dvbsub_init_decoder(AVCodecContext *avctx)

     int i, r, g, b, a = 0;

     DVBSubContext *ctx = avctx->priv_data;

-    ctx->composition_id = avctx->sub_id & 0xffff;

-    ctx->ancillary_id = avctx->sub_id >> 16;

+    if (!avctx->extradata || avctx->extradata_size != 4) {

+        av_log(avctx, AV_LOG_WARNING, "Invalid extradata, subtitle streams may be combined!\n");

+        ctx->composition_id = -1;

+        ctx->ancillary_id   = -1;

+    } else {

+        ctx->composition_id = AV_RB16(avctx->extradata);

+        ctx->ancillary_id   = AV_RB16(avctx->extradata + 2);

+    }

     default_clut.id = -1;

     default_clut.next = NULL;

@@ -1434,7 +1440,8 @@ static int dvbsub_decode(AVCodecContext *avctx,

         segment_length = AV_RB16(p);

         p += 2;

-        if (page_id == ctx->composition_id || page_id == ctx->ancillary_id) {

+        if (page_id == ctx->composition_id || page_id == ctx->ancillary_id ||

+            ctx->composition_id == -1 || ctx->ancillary_id == -1) {

             switch (segment_type) {

             case DVBSUB_PAGE_SEGMENT:

                 dvbsub_parse_page_segment(avctx, p, segment_length);

@@ -860,7 +860,6 @@ static void pmt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len

     const uint8_t *p, *p_end, *desc_list_end, *desc_end;

     int program_info_length, pcr_pid, pid, stream_type;

     int desc_list_len, desc_len, desc_tag;

-    int comp_page, anc_page;

     char language[4];

     uint32_t prog_reg_desc = 0; /* registration descriptor */

@@ -981,9 +980,17 @@ static void pmt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len

                 language[2] = get8(&p, desc_end);

                 language[3] = 0;

                 get8(&p, desc_end);

-                comp_page = get16(&p, desc_end);

-                anc_page = get16(&p, desc_end);

-                st->codec->sub_id = (anc_page << 16) | comp_page;

+                if (st->codec->extradata) {

+                    if (st->codec->extradata_size == 4 && memcmp(st->codec->extradata, p, 4))

+                        av_log_ask_for_sample(ts->stream, "DVB sub with multiple IDs\n");

+                } else {

+                    st->codec->extradata = av_malloc(4 + FF_INPUT_BUFFER_PADDING_SIZE);

+                    if (st->codec->extradata) {

+                        st->codec->extradata_size = 4;

+                        memcpy(st->codec->extradata, p, 4);

+                    }

+                }

+                p += 4;

                 av_metadata_set2(&st->metadata, "language", language, 0);

                 break;

             case 0x0a: /* ISO 639 language descriptor */