add support for parsing ac-3 audio descriptor 0x81

Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>

src/Makefile.am

@@ -66,6 +66,7 @@ pkginclude_HEADERS = dvbpsi.h psi.h descriptor.h demux.h \
                      descriptors/dr_73.h \
                      descriptors/dr_76.h \
                      descriptors/dr_7c.h \
+		     descriptors/dr_81.h \
 		     descriptors/dr_83.h \
 		     descriptors/dr_86.h \
 		     descriptors/dr_8a.h \
@@ -118,6 +119,7 @@ descriptors_src = descriptors/dr_02.c \
                   descriptors/dr_73.c \
                   descriptors/dr_76.c \
                   descriptors/dr_7c.c \
+                  descriptors/dr_81.c \
                   descriptors/dr_83.c \
                   descriptors/dr_86.c \
 		  descriptors/dr_8a.c \

src/descriptors/dr_81.c

+/*
+Copyright (C) 2013  Michael Krufky
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
+dr_81.c
+
+Decode AC-3 Audio Descriptor.
+
+*/
+#include "config.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+
+#if defined(HAVE_INTTYPES_H)
+#include <inttypes.h>
+#elif defined(HAVE_STDINT_H)
+#include <stdint.h>
+#endif
+
+#include "../dvbpsi.h"
+#include "../dvbpsi_private.h"
+#include "../descriptor.h"
+
+#include "dr_81.h"
+
+/*****************************************************************************
+ * dvbpsi_DecodeAc3AudioDr
+ *****************************************************************************/
+dvbpsi_ac3_audio_dr_t *dvbpsi_DecodeAc3AudioDr(dvbpsi_descriptor_t *p_descriptor)
+{
+    dvbpsi_ac3_audio_dr_t *p_decoded;
+    uint8_t * buf = p_descriptor->p_data;
+
+    /* Check the tag */
+    if (p_descriptor->i_tag != 0x81)
+        return NULL;
+
+    /* Don't decode twice */
+    if (p_descriptor->p_decoded)
+        return p_descriptor->p_decoded;
+
+    /* Check length */
+    if (p_descriptor->i_length < 3)
+        return NULL;
+
+    p_decoded = (dvbpsi_ac3_audio_dr_t*)malloc(sizeof(dvbpsi_ac3_audio_dr_t));
+    if (!p_decoded)
+        return NULL;
+
+    p_descriptor->p_decoded = (void*)p_decoded;
+
+    p_decoded->i_sample_rate_code = 0x07 & (buf[0] >> 5);
+    p_decoded->i_bsid             = 0x1f & buf[0];
+    p_decoded->i_bit_rate_code    = 0x3f & (buf[1] >> 2);
+    p_decoded->i_surround_mode    = 0x03 & buf[1];
+    p_decoded->i_bsmod            = 0x07 & (buf[2] >> 5);
+    p_decoded->i_num_channels     = 0x0f & (buf[2] >> 1);
+    p_decoded->b_full_svc         = 0x01 & buf[2];
+    buf += 3;
+    if (buf == p_descriptor->p_data + p_descriptor->i_length)
+        return p_decoded;
+
+    p_decoded->i_lang_code = buf[0];
+    buf++;
+
+    if (buf == p_descriptor->p_data + p_descriptor->i_length)
+        return p_decoded;
+
+    if (!p_decoded->i_num_channels) {
+        p_decoded->i_lang_code2 = buf[0];
+        buf++;
+    }
+
+    if (buf == p_descriptor->p_data + p_descriptor->i_length)
+        return p_decoded;
+
+    if (p_decoded->i_bsmod < 2) {
+        p_decoded->i_mainid       = 0x07 & (buf[0] >> 5);
+        p_decoded->i_priority     = 0x03 & (buf[0] >> 3);
+    } else
+        p_decoded->i_asvcflags = buf[0];
+    buf++;
+
+    if (buf == p_descriptor->p_data + p_descriptor->i_length)
+        return p_decoded;
+
+    p_decoded->i_textlen   = 0x7f & (buf[0] >> 1);
+    p_decoded->b_text_code = 0X01 & buf[0];
+    buf++;
+
+    memset(p_decoded->text, 0, sizeof(p_decoded->text));
+    memcpy(p_decoded->text, buf, p_decoded->i_textlen);
+    buf += p_decoded->i_textlen;
+
+    if (buf == p_descriptor->p_data + p_descriptor->i_length)
+        return p_decoded;
+
+    p_decoded->b_language_flag   = 0x01 & (buf[0] >> 7);
+    p_decoded->b_language_flag_2 = 0x01 & (buf[0] >> 6);
+    buf++;
+
+    if (p_decoded->b_language_flag) {
+        memcpy(p_decoded->language, buf, 3);
+        buf += 3;
+    }
+    if (p_decoded->b_language_flag_2) {
+        memcpy(p_decoded->language_2, buf, 3);
+        buf += 3;
+    }
+    return p_decoded;
+}

src/descriptors/dr_81.h

+/*
+Copyright (C) 2013  Michael Krufky
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
+dr_81.h
+
+Decode AC-3 Audio Descriptor.
+
+*/
+
+/*!
+ * \file dr_81.h
+ * \author Michael Krufky
+ * \brief Decode AC-3 Audio Descriptor.
+ */
+
+#ifndef _DR_81_H
+#define _DR_81_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*****************************************************************************
+ * dvbpsi_ac3_audio_dr_s
+ *****************************************************************************/
+/*!
+ * \struct dvbpsi_ac3_audio_dr_s
+ * \brief AC-3 Audio Descriptor
+ *
+ * This structure is used to store a decoded AC-3 Audio descriptor.
+ */
+/*!
+ * \typedef struct dvbpsi_ac3_audio_dr_s dvbpsi_ac3_audio_dr_t
+ * \brief dvbpsi_ac3_audio_dr_t type definition.
+ */
+typedef struct dvbpsi_ac3_audio_dr_s
+{
+    uint8_t  i_sample_rate_code; // 3bits
+    uint8_t  i_bsid;             // 5bits
+    uint8_t  i_bit_rate_code;    // 6bits
+    uint8_t  i_surround_mode;    // 2bits
+    uint8_t  i_bsmod;            // 3bits
+    uint8_t  i_num_channels;     // 4bits
+    int      b_full_svc;
+    uint8_t  i_lang_code;        // 8bits
+    uint8_t  i_lang_code2;       // 8bits
+    uint8_t  i_mainid;           // 3bits
+    uint8_t  i_priority;         // 2bits
+    uint8_t  i_asvcflags;        // 8bits
+    uint8_t  i_textlen;          // 7bits
+    int      b_text_code;
+    unsigned char text[128];
+    int      b_language_flag;
+    int      b_language_flag_2;
+    uint8_t  language[3];
+    uint8_t  language_2[3];
+}dvbpsi_ac3_audio_dr_t;
+
+/*****************************************************************************
+ * dvbpsi_DecodeAc3AudioDr
+ *****************************************************************************/
+/*!
+ * \fn dvbpsi_ac3_audio_dr_t dvbpsi_DecodeAc3AudioDr(dvbpsi_descriptor_t *p_descriptor)
+ * \brief Decode a AC-3 Audio descriptor (tag 0x81)
+ * \param p_descriptor Raw descriptor to decode.
+ * \return NULL if the descriptor could not be decoded or a pointer to a
+ *         dvbpsi_ac3_audio_dr_t structure.
+ */
+dvbpsi_ac3_audio_dr_t *dvbpsi_DecodeAc3AudioDr(dvbpsi_descriptor_t *p_descriptor);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+