[FFmpeg-devel] [PATCHv2 01/10] avformat/mpegtsenc: allow any sensible PID for elementary and PMT PIDs

Marton Balint cus at passwd.hu
Wed Nov 13 23:46:11 EET 2019


This sets the range of the first automatically assigned PMT PID or elementary
stream PID parameters to [0x20, 0x1ffa]. You can still assign manually a PID
for a stream using AVStream->id in the wider [0x10, 0x1ffe] range as specified
by ISO13818-1. But since DVB and ATSC both reserves some PIDs, let's not allow
them to be automatically assigned.

Also make sure that assigned PID numbers are valid and fix the error message
for the previous PID collision checks.

Signed-off-by: Marton Balint <cus at passwd.hu>
---
 doc/muxers.texi         |  7 ++++---
 libavformat/mpegts.h    |  2 ++
 libavformat/mpegtsenc.c | 17 ++++++++++++-----
 3 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/doc/muxers.texi b/doc/muxers.texi
index 09ded7d48a..5d7ff1ab3b 100644
--- a/doc/muxers.texi
+++ b/doc/muxers.texi
@@ -1582,11 +1582,12 @@ Advanced Codec Digital HDTV service.
 @end table
 
 @item mpegts_pmt_start_pid @var{integer}
-Set the first PID for PMT. Default is @code{0x1000}. Max is @code{0x1f00}.
+Set the first PID for PMTs. Default is @code{0x1000}, minimum is @code{0x0020},
+maximum is @code{0x1ffa}.
 
 @item mpegts_start_pid @var{integer}
-Set the first PID for data packets. Default is @code{0x0100}. Max is
- at code{0x0f00}.
+Set the first PID for elementary streams. Default is @code{0x0100}, minimum is
+ at code{0x0020}, maximum is @code{0x1ffa}.
 
 @item mpegts_m2ts_mode @var{boolean}
 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
diff --git a/libavformat/mpegts.h b/libavformat/mpegts.h
index ecc3d3374c..86a3eba4e2 100644
--- a/libavformat/mpegts.h
+++ b/libavformat/mpegts.h
@@ -58,6 +58,8 @@
 #define SIT_PID         0x001F /* Selection Information Table */
 /* PID from 0x0020 to 0x1FFA may be assigned as needed to PMT, elementary
  * streams and other data tables */
+#define FIRST_OTHER_PID 0x0020
+#define  LAST_OTHER_PID 0x1FFA
 /* PID 0x1FFB is used by DigiCipher 2/ATSC MGT metadata */
 /* PID from 0x1FFC to 0x1FFE may be assigned as needed to PMT, elementary
  * streams and other data tables */
diff --git a/libavformat/mpegtsenc.c b/libavformat/mpegtsenc.c
index 9f8f1715c9..b578539240 100644
--- a/libavformat/mpegtsenc.c
+++ b/libavformat/mpegtsenc.c
@@ -914,17 +914,24 @@ static int mpegts_init(AVFormatContext *s)
          * this range are assigned a calculated pid. */
         if (st->id < 16) {
             ts_st->pid = ts->start_pid + i;
-        } else if (st->id < 0x1FFF) {
-            ts_st->pid = st->id;
         } else {
+            ts_st->pid = st->id;
+        }
+        if (ts_st->pid >= 0x1FFF) {
             av_log(s, AV_LOG_ERROR,
                    "Invalid stream id %d, must be less than 8191\n", st->id);
             ret = AVERROR(EINVAL);
             goto fail;
         }
         for (j = 0; j < ts->nb_services; j++) {
+            if (ts->services[j]->pmt.pid > LAST_OTHER_PID) {
+                av_log(s, AV_LOG_ERROR,
+                       "Invalid PMT PID %d, must be less than %d\n", ts->services[j]->pmt.pid, LAST_OTHER_PID + 1);
+                ret = AVERROR(EINVAL);
+                goto fail;
+            }
             if (ts_st->pid == ts->services[j]->pmt.pid) {
-                av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);
+                av_log(s, AV_LOG_ERROR, "PID %d cannot be both elementary and PMT PID\n", ts_st->pid);
                 ret = AVERROR(EINVAL);
                 goto fail;
             }
@@ -1888,10 +1895,10 @@ static const AVOption options[] = {
       AV_OPT_FLAG_ENCODING_PARAM, "mpegts_service_type" },
     { "mpegts_pmt_start_pid", "Set the first pid of the PMT.",
       offsetof(MpegTSWrite, pmt_start_pid), AV_OPT_TYPE_INT,
-      { .i64 = 0x1000 }, 0x0010, 0x1f00, AV_OPT_FLAG_ENCODING_PARAM },
+      { .i64 = 0x1000 }, FIRST_OTHER_PID, LAST_OTHER_PID, AV_OPT_FLAG_ENCODING_PARAM },
     { "mpegts_start_pid", "Set the first pid.",
       offsetof(MpegTSWrite, start_pid), AV_OPT_TYPE_INT,
-      { .i64 = 0x0100 }, 0x0010, 0x0f00, AV_OPT_FLAG_ENCODING_PARAM },
+      { .i64 = 0x0100 }, FIRST_OTHER_PID, LAST_OTHER_PID, AV_OPT_FLAG_ENCODING_PARAM },
     { "mpegts_m2ts_mode", "Enable m2ts mode.",
       offsetof(MpegTSWrite, m2ts_mode), AV_OPT_TYPE_BOOL,
       { .i64 = -1 }, -1, 1, AV_OPT_FLAG_ENCODING_PARAM },
-- 
2.16.4



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