dvb/si: Complete support for descriptor 0x6a (AC-3 descriptor).

README

@@ -139,10 +139,7 @@ Supported DVB descriptors
  * Descriptor 0x67: Transport stream descriptor
  * Descriptor 0x68: DSNG descriptor
  * Descriptor 0x69: PDC descriptor
- * Descriptor 0x6a: AC-3 descriptor [p]
-
-Legend:
-  [p] - Partitial support, only parser is implemented.
+ * Descriptor 0x6a: AC-3 descriptor
 
 To see what is unsupported look in the TODO file.
 

TODO

@@ -11,7 +11,6 @@ so if you like something just do it and send a patch.
 
 - Add generators and example usage for these DVB descriptors:
   - Descriptor 0x4a: Linkage descriptor
-  - Descriptor 0x6a: AC-3 descriptor
 
 - Add support (parser, generator, example) for these DVB descriptors:
   - Descriptor 0x6b: ancillary_data_descriptor

dvb/si/desc_6a.h

@@ -4,6 +4,7 @@
  * Copyright (C) 2009-2010 VideoLAN
  *
  * Authors: Christophe Massiot <massiot@via.ecp.fr>
+ *          Georgi Chorbadzhiyski <georgi@unixsol.org>
  *
  * Permission is hereby granted, free of charge, to any person obtaining
  * a copy of this software and associated documentation files (the
@@ -49,16 +50,77 @@ extern "C"
 static inline void desc6a_init(uint8_t *p_desc)
 {
     desc_set_tag(p_desc, 0x6a);
+    desc_set_length(p_desc, (DESC6A_HEADER_SIZE - DESC_HEADER_SIZE));
+    p_desc[2] = 0x0f;
 }
 
 static inline void desc6a_clear_flags(uint8_t *p_desc)
 {
-    p_desc[2] = 0;
+    p_desc[2] = 0x0f;
+}
+
+#define DEFINE_AC3_FLAG(FLAGNAME, bit) \
+    static inline bool desc6a_get_##FLAGNAME##_flag(const uint8_t *p_desc) \
+    { \
+        return (p_desc[2] & bit) == bit; \
+    } \
+    \
+    static inline void desc6a_set_##FLAGNAME##_flag(uint8_t *p_desc, bool b_##FLAGNAME) \
+    { \
+        p_desc[2] = b_##FLAGNAME ? (p_desc[2] | bit) : (p_desc[2] &~ bit); \
+    }
+
+#define DEFINE_AC3_VALUE(VALUENAME, ofs) \
+    static inline uint8_t desc6a_get_##VALUENAME(const uint8_t *p_desc) \
+    { \
+        if (!desc6a_get_##VALUENAME##_flag(p_desc)) return 0; \
+        return p_desc[ofs]; \
+    } \
+     \
+    static inline void desc6a_set_##VALUENAME(uint8_t *p_desc, uint8_t i_##VALUENAME) \
+    { \
+        if (!desc6a_get_##VALUENAME##_flag(p_desc)) return; \
+        p_desc[ofs] = i_##VALUENAME; \
+    }
+
+DEFINE_AC3_FLAG (component_type, 0x80)
+DEFINE_AC3_VALUE(component_type, DESC6A_HEADER_SIZE)
+
+DEFINE_AC3_FLAG (bsid,   0x40)
+DEFINE_AC3_VALUE(bsid,   DESC6A_HEADER_SIZE
+                           + desc6a_get_component_type_flag(p_desc))
+
+DEFINE_AC3_FLAG (mainid, 0x20)
+DEFINE_AC3_VALUE(mainid, DESC6A_HEADER_SIZE
+                           + desc6a_get_component_type_flag(p_desc)
+                           + desc6a_get_bsid_flag(p_desc))
+
+DEFINE_AC3_FLAG (asvc,   0x10)
+DEFINE_AC3_VALUE(asvc,   DESC6A_HEADER_SIZE
+                           + desc6a_get_component_type_flag(p_desc)
+                           + desc6a_get_bsid_flag(p_desc)
+                           + desc6a_get_mainid_flag(p_desc))
+#undef DEFINE_AC3_FLAG
+#undef DEFINE_AC3_VALUE
+
+static inline void desc6a_set_length(uint8_t *p_desc)
+{
+    uint8_t i_size = (DESC6A_HEADER_SIZE - DESC_HEADER_SIZE)
+                       + desc6a_get_component_type_flag(p_desc)
+                       + desc6a_get_bsid_flag(p_desc)
+                       + desc6a_get_mainid_flag(p_desc)
+                       + desc6a_get_asvc_flag(p_desc);
+    return desc_set_length(p_desc, i_size);
 }
 
 static inline bool desc6a_validate(const uint8_t *p_desc)
 {
-    return desc_get_length(p_desc) >= DESC6A_HEADER_SIZE - DESC_HEADER_SIZE;
+    uint8_t i_size = (DESC6A_HEADER_SIZE - DESC_HEADER_SIZE)
+                       + desc6a_get_component_type_flag(p_desc)
+                       + desc6a_get_bsid_flag(p_desc)
+                       + desc6a_get_mainid_flag(p_desc)
+                       + desc6a_get_asvc_flag(p_desc);
+    return desc_get_length(p_desc) >= i_size;
 }
 
 static inline void desc6a_print(const uint8_t *p_desc, f_print pf_print,
@@ -66,10 +128,28 @@ static inline void desc6a_print(const uint8_t *p_desc, f_print pf_print,
 {
     switch (i_print_type) {
     case PRINT_XML:
-        pf_print(opaque, "<AC3_DESC />");
+        pf_print(opaque,
+                 "<AC3_DESC component_type_flag=\"%u\" component_type=\"%u\""
+                 " bsid_flag=\"%u\" bsid=\"%u\""
+                 " mainid_flag=\"%u\" mainid=\"%u\""
+                 " asvc_flag=\"%u\" asvc=\"%u\"/>",
+                    desc6a_get_component_type_flag(p_desc), desc6a_get_component_type(p_desc),
+                    desc6a_get_bsid_flag(p_desc),   desc6a_get_bsid(p_desc),
+                    desc6a_get_mainid_flag(p_desc), desc6a_get_mainid(p_desc),
+                    desc6a_get_asvc_flag(p_desc),   desc6a_get_asvc(p_desc)
+                );
         break;
     default:
-        pf_print(opaque, "    - desc 6a ac3");
+        pf_print(opaque,
+                 "    - desc 6a ac3 component_type_flag=%u component_type=%u"
+                 " bsid_flag=%u bsid=%u"
+                 " mainid_flag=%u mainid=%u"
+                 " asvc_flag=%u asvc=%u",
+                    desc6a_get_component_type_flag(p_desc), desc6a_get_component_type(p_desc),
+                    desc6a_get_bsid_flag(p_desc),   desc6a_get_bsid(p_desc),
+                    desc6a_get_mainid_flag(p_desc), desc6a_get_mainid(p_desc),
+                    desc6a_get_asvc_flag(p_desc),   desc6a_get_asvc(p_desc)
+                );
     }
 }
 

examples/dvb_gen_si.c

@@ -1102,6 +1102,24 @@ static void build_desc69(uint8_t *desc) {
 }
 
 /* DVB  Descriptor 0x6a: AC-3 descriptor */
+static void build_desc6a(uint8_t *desc) {
+    desc6a_init(desc);
+
+    desc6a_set_component_type_flag  (desc, true);
+    desc6a_set_component_type       (desc, 10);
+
+    desc6a_set_bsid_flag            (desc, true);
+    desc6a_set_bsid                 (desc, 20);
+
+    desc6a_set_mainid_flag          (desc, true);
+    desc6a_set_mainid               (desc, 30);
+
+    desc6a_set_asvc_flag            (desc, true);
+    desc6a_set_asvc                 (desc, 40);
+
+    desc6a_set_length(desc);
+}
+
 /* ---  Descriptor 0x6b: ancillary_data_descriptor */
 /* ---  Descriptor 0x6c: cell_list_descriptor */
 /* ---  Descriptor 0x6d: cell_frequency_link_descriptor */
@@ -2143,6 +2161,9 @@ static void generate_pmt(void) {
             desc = descs_get_desc(desc_loop, desc_counter++);
             build_desc5e(desc);
 
+            desc = descs_get_desc(desc_loop, desc_counter++);
+            build_desc6a(desc);
+
             // Finish descriptor generation
             desc = descs_get_desc(desc_loop, desc_counter); // Get next descriptor pos
             descs_set_length(desc_loop, desc - desc_loop - DESCS_HEADER_SIZE);

examples/dvb_print_si.output.txt

@@ -213,6 +213,7 @@ new PMT program=20000 version=1 pcrpid=110
     - desc 5e multilingual_component code="eng" component_tag=46 text="Stereo"
     - desc 5e multilingual_component code="fre" component_tag=46 text="Stereo"
     - desc 5e multilingual_component code="bul" component_tag=46 text="Stereo"
+    - desc 6a ac3 component_type_flag=1 component_type=10 bsid_flag=1 bsid=20 mainid_flag=1 mainid=30 asvc_flag=1 asvc=40
   * ES pid=122 streamtype=0x06 streamtype_txt="13818-1 PES private data"
     - desc 46 vbi_telx language=eng type=0x1 type_txt="Initial teletext page" mag=3 page=0x255x
     - desc 46 vbi_telx language=bul type=0x2 type_txt="Teletext subtitle page" mag=2 page=0x127x

examples/dvb_print_si.output.xml

@@ -378,6 +378,9 @@
 <MULTILINGUAL_COMPONENT_DESC code="fre" component_tag="46" text="Stereo"/>
 <MULTILINGUAL_COMPONENT_DESC code="bul" component_tag="46" text="Stereo"/>
 </DESC>
+<DESC id="0x6a" length="5" value="ff0a141e28">
+<AC3_DESC component_type_flag="1" component_type="10" bsid_flag="1" bsid="20" mainid_flag="1" mainid="30" asvc_flag="1" asvc="40"/>
+</DESC>
 </ES>
 <ES pid="122" streamtype="0x06" streamtype_txt="13818-1 PES private data">
 <DESC id="0x46" length="15" value="656e670bff62756c127f6672651940">