diff options
Diffstat (limited to 'dabplussnoop.cpp')
| -rw-r--r-- | dabplussnoop.cpp | 149 |
1 files changed, 117 insertions, 32 deletions
diff --git a/dabplussnoop.cpp b/dabplussnoop.cpp index 40cb124..c0fbcca 100644 --- a/dabplussnoop.cpp +++ b/dabplussnoop.cpp @@ -26,6 +26,7 @@ #include <stdlib.h> #include <string.h> #include <string> +#include <cassert> #include <sstream> #include <algorithm> #include <vector> @@ -34,7 +35,9 @@ #include "lib_crc.h" #define DPS_INDENT "\t\t" -#define DPS_PREFIX "DABPLUS:" +#define DPS_PREFIX "DAB+ decode:" + +#define DPS_DEBUG 0 using namespace std; @@ -82,13 +85,17 @@ bool DabPlusSnoop::seek_valid_firecode() } if (crc_ok) { - fprintf(stderr, DPS_PREFIX " Found valid FireCode at %zu\n", i); +#if DPS_DEBUG + printf(DPS_PREFIX " Found valid FireCode at %zu\n", i); +#endif m_data.erase(m_data.begin(), m_data.begin() + i); return true; } else { - fprintf(stderr, DPS_PREFIX " No valid FireCode found\n"); +#if DPS_DEBUG + printf(DPS_PREFIX " No valid FireCode found\n"); +#endif m_data.clear(); return false; @@ -97,9 +104,11 @@ bool DabPlusSnoop::seek_valid_firecode() bool DabPlusSnoop::decode() { - fprintf(stderr, DPS_PREFIX " We have %zu bytes of data\n", m_data.size()); +#if DPS_DEBUG + printf(DPS_PREFIX " We have %zu bytes of data\n", m_data.size()); +#endif - if (m_subchannel_index && m_data.size() >= m_subchannel_index * 110) { + if (m_subchannel_index && m_data.size() >= m_subchannel_index * 120) { uint8_t* b = &m_data[0]; @@ -125,8 +134,7 @@ bool DabPlusSnoop::decode() else if ((dac_rate == 1) && (sbr_flag == 0)) num_aus = 6; // AAC core sampling rate 48 kHz - fprintf(stderr, - DPS_INDENT DPS_PREFIX "\n" + printf( DPS_INDENT DPS_PREFIX "\n" DPS_INDENT "\tfirecode 0x%x\n" DPS_INDENT "\trfa %d\n" DPS_INDENT "\tdac_rate %d\n" @@ -151,20 +159,15 @@ bool DabPlusSnoop::decode() char nibble = b[i/2] >> 4; au_start_nibbles.push_back( nibble ); - - fprintf(stderr, "0x%1x", nibble); } else { char nibble = b[i/2] & 0x0F; au_start_nibbles.push_back( nibble ); - - fprintf(stderr, "0x%1x", nibble); } } - fprintf(stderr, "\n"); vector<int> au_start(num_aus); @@ -179,7 +182,6 @@ bool DabPlusSnoop::decode() int nib = 0; - fprintf(stderr, DPS_INDENT DPS_PREFIX " AU start\n"); for (int au = 1; au < num_aus; au++) { au_start[au] = au_start_nibbles[nib] << 8 | \ au_start_nibbles[nib+1] << 4 | \ @@ -188,41 +190,41 @@ bool DabPlusSnoop::decode() nib += 3; } +#if DPS_DEBUG + printf(DPS_INDENT DPS_PREFIX " AU start\n"); for (int au = 0; au < num_aus; au++) { - fprintf(stderr, DPS_INDENT "\tAU[%d] %d 0x%x\n", au, + printf(DPS_INDENT "\tAU[%d] %d 0x%x\n", au, au_start[au], au_start[au]); } +#endif - return analyse_au(au_start); + return extract_au(au_start); } else { return false; } } -bool DabPlusSnoop::analyse_au(vector<int> au_start) +bool DabPlusSnoop::extract_au(vector<int> au_start) { - - /* - for (int i = 0; i < au_start.length - 1; i++) { - byte[] new_frame = Arrays.copyOfRange(frame, au_start[i], au_start[i+1] - 2); - - int current_crc = MiscTools.getUInt16(frame, au_start[i+1] - 2); - int crc = MiscTools.calcCRC(new_frame, MiscTools.crc_mode.CRC_16_CCITT); - } -*/ - vector<vector<uint8_t> > aus(au_start.size()); + // The last entry of au_start must the end of valid + // AU data. We stop at m_subchannel_index * 110 because + // what comes after is RS parity au_start.push_back(m_subchannel_index * 110); + bool all_crc_ok = true; + for (size_t au = 0; au < aus.size(); au++) { - fprintf(stderr, DPS_PREFIX DPS_INDENT +#if DPS_DEBUG + printf(DPS_PREFIX DPS_INDENT "Copy au %zu of size %zu\n", au, au_start[au+1] - au_start[au]-2 ); +#endif aus[au].resize(au_start[au+1] - au_start[au]-2); std::copy( @@ -242,11 +244,94 @@ bool DabPlusSnoop::analyse_au(vector<int> au_start) } calc_crc =~ calc_crc; - fprintf(stderr, DPS_PREFIX DPS_INDENT - " AU H: %04x C: %04x\n" - " DAU H: %u C: %u\n", - au_crc, calc_crc, - au_crc, calc_crc); + if (calc_crc != au_crc) { + printf(DPS_INDENT DPS_PREFIX + "Erroneous CRC for au %zu\n", au); + + all_crc_ok = false; + } + } + + if (all_crc_ok) { + return analyse_au(aus); + } + else { + return false; + } +} + +bool DabPlusSnoop::analyse_au(vector<vector<uint8_t> >& aus) +{ + for (size_t i_au = 0; i_au < aus.size(); i_au++) { + size_t i = 0; + + vector<uint8_t>& au = aus[i_au]; + + bool continue_au = true; + while (continue_au && i < au.size()) { + printf("R at %zu\n", i); + int id_syn_ele = (au[i] & 0xE0) >> 5; + + /* Debugging print */ + stringstream ss; + ss << DPS_INDENT << "\tID_SYN_ELE: "; + + switch (id_syn_ele) { + case ID_SCE: ss << "Single Channel Element"; break; + case ID_CPE: ss << "Channel Pair Element"; break; + case ID_CCE: ss << "Coupling Channel Element"; break; + case ID_LFE: ss << "LFE Channel Element"; break; + case ID_DSE: ss << "Data Stream Element"; break; + case ID_PCE: ss << "Program Config Element"; break; + case ID_FIL: ss << "Fill Element"; break; + case ID_END: ss << "Terminator"; break; + case ID_EXT: ss << "Extension Payload"; break; + case ID_SCAL: ss << "AAC scalable element"; break; + default: ss << "Unknown (" << id_syn_ele << ")"; break; + } + + int element_instance_tag = (au[i] & 0x78) >> 1; + ss << " [" << element_instance_tag << "]"; + + + // Keep track of index increment in bits + size_t inc = 7; // eat id_syn_ele, element_instance_tag + + if (id_syn_ele == ID_DSE) { + bool data_byte_align_flag = (au[i] & 0x01); + inc++; + + ss << "\n" DPS_INDENT "\t\t"; + if (data_byte_align_flag) { + ss << " <byte align flag>"; + } + + + uint8_t count = au[1]; + int cnt = count; + inc += 8; + + if (count == 255) { + uint8_t esc_count = au[2]; + inc += 8; + + cnt += esc_count; + } + + ss << " cnt:" << cnt; + inc += 8*cnt; + + } + else + { + continue_au = false; + } + + printf("%s\n", ss.str().c_str()); + + assert (inc % 8 == 0); + i += inc / 8; + } } return true; |