add support for the IBP descriptor

Signed-off-by: Jean-Paul Saman <jpsaman@videolan.org>

src/Makefile.am

@@ -36,6 +36,7 @@ pkginclude_HEADERS = dvbpsi.h psi.h descriptor.h demux.h \
                      descriptors/dr_0f.h \
                      descriptors/dr_10.h \
                      descriptors/dr_11.h \
+                     descriptors/dr_12.h \
                      descriptors/dr_13.h \
                      descriptors/dr_14.h \
 		     descriptors/dr_40.h \
@@ -92,6 +93,7 @@ descriptors_src = descriptors/dr_02.c \
                   descriptors/dr_0f.c \
                   descriptors/dr_10.c \
                   descriptors/dr_11.c \
+                  descriptors/dr_12.c \
                   descriptors/dr_13.c \
                   descriptors/dr_14.c \
 		  descriptors/dr_40.c \

src/descriptors/dr_12.c

+/*
+Copyright (C) 2015 Daniel Kamil Kozar
+
+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
+*/
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <stdbool.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_12.h"
+
+dvbpsi_ibp_dr_t* dvbpsi_DecodeIBPDr(dvbpsi_descriptor_t * p_descriptor)
+{
+    dvbpsi_ibp_dr_t * p_decoded;
+    
+    /* check the tag. */
+    if (!dvbpsi_CanDecodeAsDescriptor(p_descriptor, 0x12))
+        return NULL;
+    
+    /* don't decode twice. */
+    if (dvbpsi_IsDescriptorDecoded(p_descriptor))
+        return p_descriptor->p_decoded;
+    
+    /* all descriptors of this type have 2 bytes of payload. */
+    if (p_descriptor->i_length != 2)
+        return NULL;
+    
+    p_decoded = (dvbpsi_ibp_dr_t*)malloc(sizeof(*p_decoded));
+    if (!p_decoded)
+        return NULL;
+    
+    p_decoded->b_closed_gop_flag = p_descriptor->p_data[0] & 0x80;
+    p_decoded->b_identical_gop_flag = p_descriptor->p_data[0] & 0x40;
+    p_decoded->i_max_gop_length = 
+        (((uint16_t)p_descriptor->p_data[0] & 0x3f) << 8)
+        | p_descriptor->p_data[1];
+    
+    /* a value of 0 is forbidden for max_gop_length. */
+    if(p_decoded->i_max_gop_length == 0)
+    {
+        free(p_decoded);
+        return NULL;
+    }
+    
+    p_descriptor->p_decoded = (void*)p_decoded;
+    
+    return p_decoded;
+}
+
+dvbpsi_descriptor_t * dvbpsi_GenIBPDr(dvbpsi_ibp_dr_t * p_decoded)
+{
+    dvbpsi_descriptor_t * p_descriptor = dvbpsi_NewDescriptor(0x12, 2, NULL);
+    if (!p_descriptor)
+        return NULL;
+    
+    /* encode the data. */
+    p_descriptor->p_data[0]  = p_decoded->b_closed_gop_flag << 7;
+    p_descriptor->p_data[0] |= p_decoded->b_identical_gop_flag << 6;
+    p_descriptor->p_data[0] |= p_decoded->i_max_gop_length >> 8;
+    
+    p_descriptor->p_data[1] = p_decoded->i_max_gop_length;
+    
+    return p_descriptor;
+}

src/descriptors/dr_12.h

+/*
+Copyright (C) 2015 Daniel Kamil Kozar
+
+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
+*/
+
+/*!
+ * \file <dr_12.h>
+ * \author Daniel Kamil Kozar <dkk089 at gmail.com>
+ * \brief Application interface for the MPEG-2 IBP descriptor decoder and
+ * generator.
+ *
+ * Application interface for the MPEG-2 IBP descriptor decoder and generator.
+ * This descriptor's definition can be found in ISO/IEC 13818-1 revision 2014/10
+ * section 2.6.34.
+ */
+
+#ifndef _DVBPSI_DR_12_H_
+#define _DVBPSI_DR_12_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*!
+ * \struct dvbpsi_ibp_dr_s
+ * \brief IBP descriptor structure.
+ *
+ * This structure is used to store a decoded IBP descriptor. (ISO/IEC 13818-1
+ * section 2.6.34).
+ */
+
+/*!
+ * \typedef struct dvbpsi_ibp_dr_s dvbpsi_ibp_dr_t
+ * \brief dvbpsi_ibp_dr_s type definition.
+ */
+typedef struct dvbpsi_ibp_dr_s
+{
+  bool          b_closed_gop_flag; /*!< closed_gop_flag */
+  bool          b_identical_gop_flag; /*!< identical_gop_flag */
+  uint16_t      i_max_gop_length; /*!< max_gop_length */
+} dvbpsi_ibp_dr_t;
+
+/*!
+ * \brief IBP descriptor decoder.
+ * \param p_descriptor pointer to the descriptor structure
+ * \return A pointer to a new IBP descriptor structure which contains the
+ * decoded data.
+ */
+dvbpsi_ibp_dr_t* dvbpsi_DecodeIBPDr(dvbpsi_descriptor_t * p_descriptor);
+
+/*!
+ * \brief IBP descriptor generator.
+ * \param p_decoded pointer to a decoded IBP descriptor structure.
+ * \return a pointer to a new descriptor structure which contains encoded data.
+ */
+dvbpsi_descriptor_t * dvbpsi_GenIBPDr(dvbpsi_ibp_dr_t * p_decoded);
+
+#ifdef __cplusplus
+}
+#endif
+
+#else
+#error "Multiple inclusions of dr_12.h"
+#endif