[FFmpeg-devel] [PATCH v3 1/3] avformat/mpegtsenc: Fix mpegts_write_pes() for private_stream_2 and other types

[zheng qian]

Changes since v2:
  Fix PES_packet_length mismatch bug

According to the PES packet definition defined in Table 2-17
of ISO_IEC_13818-1 specification, some fields like PTS/DTS or
pes_extension could only appears if the stream_id meets the
condition:

if (stream_id != 0xBC &&  // program_stream_map
stream_id != 0xBE &&  // padding_stream
stream_id != 0xBF &&  // private_stream_2
stream_id != 0xF0 &&  // ECM
stream_id != 0xF1 &&  // EMM
stream_id != 0xFF &&  // program_stream_directory
stream_id != 0xF2 &&  // DSMCC_stream
stream_id != 0xF8)     // ITU-T Rec. H.222.1 type E stream

And the following stream_id types don't have fields like PTS/DTS:

else if ( stream_id == program_stream_map
|| stream_id == private_stream_2
|| stream_id == ECM
|| stream_id == EMM
|| stream_id == program_stream_directory
|| stream_id == DSMCC_stream
|| stream_id == ITU-T Rec. H.222.1 type E stream ) {
    for (i = 0; i < PES_packet_length; i++) {
        PES_packet_data_byte
    }
}

Current implementation skipped the judgement of stream_id
causing some kind of stream like private_stream_2 to be
incorrectly written with PTS/DTS field. For example,
Japan DTV transmits news and alerts through ARIB superimpose
that utilizes private_stream_2 still could not be remuxed
correctly for now.

This patch set fixes the remuxing for private_stream_2 and
other stream_id types.

Signed-off-by: zheng qian <xqq at xqq.im>
---
 libavformat/mpegtsenc.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/libavformat/mpegtsenc.c b/libavformat/mpegtsenc.c
index f302af84ff..b59dab5174 100644
--- a/libavformat/mpegtsenc.c
+++ b/libavformat/mpegtsenc.c
@@ -1476,6 +1476,16 @@ static void mpegts_write_pes(AVFormatContext *s, AVStream *st,
                 }
             }
             header_len = 0;
+
+            if (stream_id != 0xBC &&  // program_stream_map
+                stream_id != 0xBE &&  // padding_stream
+                stream_id != 0xBF &&  // private_stream_2
+                stream_id != 0xF0 &&  // ECM
+                stream_id != 0xF1 &&  // EMM
+                stream_id != 0xFF &&  // program_stream_directory
+                stream_id != 0xF2 &&  // DSMCC_stream
+                stream_id != 0xF8) {  // ITU-T Rec. H.222.1 type E stream
+
             flags      = 0;
             if (pts != AV_NOPTS_VALUE) {
                 header_len += 5;
@@ -1569,6 +1579,11 @@ static void mpegts_write_pes(AVFormatContext *s, AVStream *st,
                 memset(q, 0xff, pes_header_stuffing_bytes);
                 q += pes_header_stuffing_bytes;
             }
+            } else {
+                len = payload_size;
+                *q++ = len >> 8;
+                *q++ = len;
+            }
             is_start = 0;
         }
         /* header size */
-- 
2.29.2