[FFmpeg-devel] [PATCH v2] avformat/mpegts: set data broadcast streams as such

Jan Ekström jeebjp at gmail.com
Mon Apr 11 13:50:31 EEST 2022


From: Jan Ekström <jan.ekstrom at 24i.com>

Additionally, they should not be probed, as this is essentially
various types of binary data.

Signed-off-by: Jan Ekström <jan.ekstrom at 24i.com>
---
 libavformat/mpegts.c                        | 53 +++++++++++++++++++++
 tests/fate/mpegts.mak                       |  3 ++
 tests/ref/fate/mpegts-probe-sdt-data-stream | 14 ++++++
 3 files changed, 70 insertions(+)
 create mode 100644 tests/ref/fate/mpegts-probe-sdt-data-stream

diff --git a/libavformat/mpegts.c b/libavformat/mpegts.c
index 49f7735123..d41f7fc8bd 100644
--- a/libavformat/mpegts.c
+++ b/libavformat/mpegts.c
@@ -2516,6 +2516,13 @@ static void pmt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len
             }
         }
         p = desc_list_end;
+
+        if (!ts->pkt && (stream_type >= 0x80 && stream_type <= 0xFF) &&
+            st->codecpar->codec_id == AV_CODEC_ID_NONE)
+            // if we are reading headers, and still have a user private stream
+            // with no proper codec set, do not stop reading at PMT. Data
+            // streams are marked within SDT.
+            ts->stop_parse = 0;
     }
 
     if (!ts->pids[pcr_pid])
@@ -2699,6 +2706,7 @@ static void sdt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len
     if (val < 0)
         return;
     for (;;) {
+        struct Program *program = NULL;
         sid = get16(&p, p_end);
         if (sid < 0)
             break;
@@ -2712,6 +2720,15 @@ static void sdt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len
         desc_list_end  = p + desc_list_len;
         if (desc_list_end > p_end)
             break;
+
+        program = get_program(ts, sid);
+
+        if (!ts->pkt && program && program->pmt_found)
+            // if during header reading we have already received a PMT for
+            // this program and now have received an SDT for it, stop further
+            // reading at this point.
+            ts->stop_parse = 2;
+
         for (;;) {
             desc_tag = get8(&p, desc_list_end);
             if (desc_tag < 0)
@@ -2744,6 +2761,42 @@ static void sdt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len
                 av_free(name);
                 av_free(provider_name);
                 break;
+            case 0x64: /* ETSI data broadcast descriptor; EN 300 468 6.2.11 */
+                if (desc_len < 3)
+                    // length of the always available header part, up to and
+                    // including the component_tag field.
+                    break;
+
+                {
+                    AVStream *st  = NULL;
+                    FFStream *sti = NULL;
+
+                    int data_broadcast_id = get16(&p, desc_end); // TS 101 162
+                    int component_tag     = get8(&p, desc_end);
+                    if (!component_tag)
+                        // no stream mapping according to component_tag
+                        break;
+
+                    av_log(ts->stream, AV_LOG_TRACE,
+                           "data broadcast id: %d, component tag: %d\n",
+                           data_broadcast_id, component_tag);
+
+                    if (!program)
+                        break;
+
+                    st = find_matching_stream(ts, 0, sid, component_tag + 1, 0,
+                                              program);
+                    if (!st)
+                        break;
+
+                    sti = ffstream(st);
+
+                    st->codecpar->codec_type = AVMEDIA_TYPE_DATA;
+                    st->codecpar->codec_id   = AV_CODEC_ID_BIN_DATA;
+                    sti->request_probe = sti->need_parsing = 0;
+                    sti->need_context_update = 1;
+                    break;
+                }
             default:
                 break;
             }
diff --git a/tests/fate/mpegts.mak b/tests/fate/mpegts.mak
index bbcbfc47b2..ae21ee87d0 100644
--- a/tests/fate/mpegts.mak
+++ b/tests/fate/mpegts.mak
@@ -19,6 +19,9 @@ FATE_MPEGTS_PROBE-$(call DEMDEC, MPEGTS) += fate-mpegts-probe-pmt-merge
 fate-mpegts-probe-pmt-merge: SRC = $(TARGET_SAMPLES)/mpegts/pmtchange.ts
 fate-mpegts-probe-pmt-merge: CMD = run $(PROBE_CODEC_NAME_COMMAND) -merge_pmt_versions 1 -i "$(SRC)"
 
+FATE_MPEGTS_PROBE-$(call DEMDEC, MPEGTS, MP2) += fate-mpegts-probe-sdt-data-stream
+fate-mpegts-probe-sdt-data-stream: SRC = $(TARGET_SAMPLES)/mpegts/mpegts_sdt_data_stream.ts
+fate-mpegts-probe-sdt-data-stream: CMD = run $(PROBE_CODEC_NAME_COMMAND) -i "$(SRC)"
 
 FATE_SAMPLES_FFPROBE += $(FATE_MPEGTS_PROBE-yes)
 
diff --git a/tests/ref/fate/mpegts-probe-sdt-data-stream b/tests/ref/fate/mpegts-probe-sdt-data-stream
new file mode 100644
index 0000000000..0b8e90962f
--- /dev/null
+++ b/tests/ref/fate/mpegts-probe-sdt-data-stream
@@ -0,0 +1,14 @@
+[PROGRAM]
+[STREAM]
+codec_name=mp2
+[/STREAM]
+[STREAM]
+codec_name=bin_data
+[/STREAM]
+[/PROGRAM]
+[STREAM]
+codec_name=mp2
+[/STREAM]
+[STREAM]
+codec_name=bin_data
+[/STREAM]
-- 
2.35.1



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