[libdvbpsi-devel] add support for parsing ac-3 audio descriptor 0x81
Michael Krufky
git at videolan.org
Tue Feb 4 11:21:57 CET 2014
libdvbpsi | branch: master | Michael Krufky <mkrufky at linuxtv.org> | Mon May 20 20:09:08 2013 -0400| [c354e17665d4e1a72c5c7c9036682d92e9c3b319] | committer: Jean-Paul Saman
add support for parsing ac-3 audio descriptor 0x81
Signed-off-by: Michael Krufky <mkrufky at linuxtv.org>
> http://git.videolan.org/gitweb.cgi/libdvbpsi.git/?a=commit;h=c354e17665d4e1a72c5c7c9036682d92e9c3b319
---
src/Makefile.am | 2 +
src/descriptors/dr_81.c | 127 +++++++++++++++++++++++++++++++++++++++++++++++
src/descriptors/dr_81.h | 90 +++++++++++++++++++++++++++++++++
3 files changed, 219 insertions(+)
diff --git a/src/Makefile.am b/src/Makefile.am
index 61ec5ae..5ebab6d 100644
--- a/src/Makefile.am
+++ b/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 \
diff --git a/src/descriptors/dr_81.c b/src/descriptors/dr_81.c
new file mode 100644
index 0000000..800e145
--- /dev/null
+++ b/src/descriptors/dr_81.c
@@ -0,0 +1,127 @@
+/*
+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;
+}
diff --git a/src/descriptors/dr_81.h b/src/descriptors/dr_81.h
new file mode 100644
index 0000000..567eec0
--- /dev/null
+++ b/src/descriptors/dr_81.h
@@ -0,0 +1,90 @@
+/*
+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
+
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