mpegts: Fix some packetizing bugs

- Length of NIT stream descriptors was not detected correct
- Reserved bits was not set according to EN 300 468, ISO/IEC 13818-1
- Also set output data size if the section was previously packetized

https://bugzilla.gnome.org/show_bug.cgi?id=723892

2 files changed, 13 insertions, 4 deletions

diff --git a/gst-libs/gst/mpegts/gst-dvb-section.c b/gst-libs/gst/mpegts/gst-dvb-section.c
index cd0a493f0..652cf1dce 100644
--- a/gst-libs/gst/mpegts/gst-dvb-section.c
+++ b/gst-libs/gst/mpegts/gst-dvb-section.c
@@ -685,7 +685,7 @@ _packetize_nit (GstMpegTsSection * section)
       loop_length += 6;
       if (stream->descriptors) {
         for (j = 0; j < stream->descriptors->len; j++) {
-          descriptor = g_ptr_array_index (stream->descriptors, i);
+          descriptor = g_ptr_array_index (stream->descriptors, j);
           loop_length += descriptor->length + 2;
         }
       }
@@ -734,7 +734,7 @@ _packetize_nit (GstMpegTsSection * section)
       _packetize_descriptor_array (stream->descriptors, &data);
 
       /* Go back and update the descriptor length */
-      GST_WRITE_UINT16_BE (pos, data - pos - 2);
+      GST_WRITE_UINT16_BE (pos, (data - pos - 2) | 0xF000);
     }
   }
 
diff --git a/gst-libs/gst/mpegts/gstmpegtssection.c b/gst-libs/gst/mpegts/gstmpegtssection.c
index 1c95c0149..6b17ec09d 100644
--- a/gst-libs/gst/mpegts/gstmpegtssection.c
+++ b/gst-libs/gst/mpegts/gstmpegtssection.c
@@ -1087,7 +1087,14 @@ _packetize_common_section (GstMpegTsSection * section, gsize length)
   /* section_syntax_indicator         - 1  bit
      reserved                         - 3  bit
      section_length                   - 12 bit uimsbf */
-  GST_WRITE_UINT16_BE (data, (section->section_length - 3) | 0x7000);
+  if (section->section_type == (GST_MPEGTS_SECTION_PAT ||
+          GST_MPEGTS_SECTION_PMT ||
+          GST_MPEGTS_SECTION_CAT || GST_MPEGTS_SECTION_TSDT)) {
+    /* Tables from ISO/IEC 13818-1 has a '0' bit
+     * after the section_syntax_indicator */
+    GST_WRITE_UINT16_BE (data, (section->section_length - 3) | 0x3000);
+  } else
+    GST_WRITE_UINT16_BE (data, (section->section_length - 3) | 0x7000);
 
   if (!section->short_section)
     *data |= 0x80;
@@ -1206,8 +1213,10 @@ gst_mpegts_section_packetize (GstMpegTsSection * section, gsize * output_size)
   g_return_val_if_fail (section->packetizer != NULL, NULL);
 
   /* Section data has already been packetized */
-  if (section->data)
+  if (section->data) {
+    *output_size = section->section_length;
     return section->data;
+  }
 
   if (!section->packetizer (section))
     return NULL;