1 files changed, 133 insertions, 0 deletions
diff --git a/dabplussnoop.hpp b/dabplussnoop.hpp
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+++ b/dabplussnoop.hpp
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+/*
+    Copyright (C) 2014 Matthias P. Braendli (http://www.opendigitalradio.org)
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program 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 General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+    dabplussnoop.cpp
+          Parse DAB+ frames from a ETI file
+
+    Authors:
+         Matthias P. Braendli <matthias@mpb.li>
+*/
+
+/* From the spec:
+
+subchannel_index = MSC sub-channel size (kbps) / 8
+audio_super_frame_size (bytes) = subchannel_index * 110
+
+// Derived from
+// au_start[n] = au_start[n - 1] + au_size[n - 1] + 2;
+// 2 bytes for CRC
+au_size[n] = au_start[n+1] - au_start[n] - 2;
+
+he_aac_super_frame(subchannel_index)
+{
+    he_aac_super_frame_header()
+    {
+        header_firecode       16
+        rfa                    1
+        dac_rate               1
+        sbr_flag               1
+        aac_channel_mode       1
+        ps_flag                1
+        mpeg_surround_config   3
+
+        // end of audio parameters
+        if ((dac_rate == 0) && (sbr_flag == 1)) num_aus = 2;
+        // AAC core sampling rate 16 kHz
+        if ((dac_rate == 1) && (sbr_flag == 1)) num_aus = 3;
+        //  AAC core sampling rate 24 kHz
+        if ((dac_rate == 0) && (sbr_flag == 0)) num_aus = 4;
+        // AAC core sampling rate 32 kHz
+        if ((dac_rate == 1) && (sbr_flag == 0)) num_aus = 6;
+        // AAC core sampling rate 48 kHz
+
+        for (n = 1; n < num_aus; n++) {
+            au_start[n];      12
+        }
+
+        if !((dac_rate == 1) && (sbr_flag == 1))
+        alignment              4
+    }
+
+    for (n = 0; n < num_aus; n++) {
+        au[n]                  8 * au_size[n]
+        au_crc[n]             16
+    }
+
+}
+*/
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <string>
+#include <sstream>
+#include <vector>
+#include "faad_decoder.hpp"
+
+#ifndef __DABPLUSSNOOP_H_
+#define __DABPLUSSNOOP_H_
+
+
+class DabPlusSnoop
+{
+    public:
+        DabPlusSnoop() :
+            m_index(0),
+            m_subchannel_index(0),
+            m_data(0),
+            m_raw_data_stream_fd(NULL) {}
+
+        void set_subchannel_index(unsigned subchannel_index)
+        {
+            m_subchannel_index = subchannel_index;
+        }
+
+        void set_index(int index)
+        {
+            m_index = index;
+        }
+
+        void push(uint8_t* streamdata, size_t streamsize);
+
+        void close(void);
+
+    private:
+        /* Data needed for FAAD */
+        FaadDecoder m_faad_decoder;
+        int  m_index;
+
+        bool m_ps_flag;
+        bool m_aac_channel_mode;
+        bool m_dac_rate;
+        bool m_sbr_flag;
+        int  m_mpeg_surround_config;
+
+        /* Functions */
+
+        bool seek_valid_firecode(void);
+        bool decode(void);
+        bool extract_au(std::vector<int> au_start);
+        bool analyse_au(std::vector<std::vector<uint8_t> >& aus);
+
+        unsigned m_subchannel_index;
+        std::vector<uint8_t> m_data;
+
+        FILE* m_raw_data_stream_fd;
+};
+
+#endif
+