diff options
author | 2012-12-31 22:04:28 +0000 | |
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committer | 2012-12-31 22:04:28 +0000 | |
commit | fd0960a746f5a42760548d1467536940f9307040 (patch) | |
tree | 3c34b0aebd318eb11447c1de615c53e1cb75d34c /src/emu/sound/mpeg_audio.c | |
parent | 7e652d13c538f96ee0d43207cd373e4f53d06805 (diff) |
Split AMM decoder from YMZ770 and add MPEG layer 1/2 support [O. Galibert]
De-skeletonized Sega Z80 type Digital Sound Board, hooked up to swa [R. Belmont, O. Galibert]
Diffstat (limited to 'src/emu/sound/mpeg_audio.c')
-rw-r--r-- | src/emu/sound/mpeg_audio.c | 752 |
1 files changed, 752 insertions, 0 deletions
diff --git a/src/emu/sound/mpeg_audio.c b/src/emu/sound/mpeg_audio.c new file mode 100644 index 00000000000..94f11c72842 --- /dev/null +++ b/src/emu/sound/mpeg_audio.c @@ -0,0 +1,752 @@ +/*************************************************************************** + + MPEG audio support. Only layer2 and variants for now. + +***************************************************************************/ + +#include "emu.h" +#include "mpeg_audio.h" + +mpeg_audio::mpeg_audio(const void *_base, unsigned int _accepted, bool lsb_first, int _position_align) +{ + base = (const UINT8 *)_base; + accepted = _accepted; + do_gb = lsb_first ? do_gb_lsb : do_gb_msb; + position_align = _position_align ? _position_align - 1 : 0; + + memset(audio_buffer, 0, sizeof(audio_buffer)); + audio_buffer_pos[0] = 16*32; + audio_buffer_pos[1] = 16*32; +} + + +bool mpeg_audio::decode_buffer(int &pos, int limit, short *output, + int &output_samples, int &sample_rate, int &channels) +{ + if(limit - pos < 16) + return false; + + // Scan for the sync mark + // + // Avoid the exception dance at the point where going out of bound + // is the most probable and easily avoidable + + current_pos = pos; + current_limit = limit; + unsigned short sync = do_gb(base, current_pos, 12); + + retry_sync: + while(sync != 0xfff && current_pos < limit) + sync = ((sync << 1) | do_gb(base, current_pos, 1)) & 0xfff; + + if(limit - current_pos < 4) + return false; + + int layer = 0; + int variant = do_gb(base, current_pos, 3); + switch(variant) { + case 2: + if(accepted & L2_5) + layer = 2; + else if(accepted & AMM) + layer = 4; + break; + + case 5: + if(accepted & L3) + layer = 3; + break; + + case 6: + if(accepted & (L2|L2_5)) + layer = 2; + else if(accepted & AMM) + layer = 4; + break; + + case 7: + if(accepted & L1) + layer = 1; + break; + } + + if(!layer) { + current_pos -= 3; + sync = ((sync << 1) | do_gb(base, current_pos, 1)) & 0xfff; + goto retry_sync; + } + + switch(layer) { + case 1: + abort(); + case 2: + try { + read_header_mpeg2(variant == 2); + read_data_mpeg2(); + decode_mpeg2(output, output_samples); + } catch(limit_hit) { + return false; + } + break; + case 3: + abort(); + case 4: + try { + read_header_amm(variant == 2); + read_data_mpeg2(); + decode_mpeg2(output, output_samples); + } catch(limit_hit) { + return false; + } + break; + } + + if(position_align) + current_pos = (current_pos + position_align) & ~position_align; + + pos = current_pos; + sample_rate = sample_rates[sampling_rate]; + channels = channel_count; + return true; +} + +void mpeg_audio::read_header_amm(bool layer25) +{ + gb(1); // unused + int full_packets_count = gb(4); // max 12 + int srate_index = gb(2); // max 2 + sampling_rate = srate_index + 4 * layer25; + int last_packet_frame_id = gb(2); // max 2 + last_frame_number = 3*full_packets_count + last_packet_frame_id; + int stereo_mode = gb(2); + int stereo_mode_ext = gb(2); + param_index = gb(3); + gb(1); // must be zero + + channel_count = stereo_mode != 3 ? 2 : 1; + + total_bands = total_band_counts[param_index]; + joint_bands = total_bands; + if(stereo_mode == 1) // joint stereo + joint_bands = joint_band_counts[stereo_mode_ext]; + if(joint_bands > total_bands ) + joint_bands = total_bands; +} + +void mpeg_audio::read_header_mpeg2(bool layer25) +{ + int prot = gb(1); + int bitrate_index = gb(4); + sampling_rate = gb(2); + gb(1); // padding + gb(1); + last_frame_number = 36; + int stereo_mode = gb(2); + int stereo_mode_ext = gb(2); + gb(2); // copyright, original + gb(2); // emphasis + if(!prot) + gb(16); // crc + + channel_count = stereo_mode != 3 ? 2 : 1; + + param_index = layer2_param_index[channel_count-1][sampling_rate][bitrate_index]; + assert(param_index != -1); + + total_bands = total_band_counts[param_index]; + joint_bands = total_bands; + if(stereo_mode == 1) // joint stereo + joint_bands = joint_band_counts[stereo_mode_ext]; + if(joint_bands > total_bands ) + joint_bands = total_bands; +} + +void mpeg_audio::read_data_mpeg2() +{ + read_band_params(); + read_scfci(); + read_band_amplitude_params(); +} + +void mpeg_audio::decode_mpeg2(short *output, int &output_samples) +{ + output_samples = 0; + build_amplitudes(); + + // Supposed to stop at last_frame_number when it's not 12*3+2 = 38 + int frame_number = 0; + for(int upper_step = 0; upper_step<3; upper_step++) + for(int middle_step = 0; middle_step < 4; middle_step++) { + build_next_segments(upper_step); + for(int lower_step = 0; lower_step < 3; lower_step++) { + retrieve_subbuffer(lower_step); + + for(int chan=0; chan<channel_count; chan++) { + double resynthesis_buffer[32]; + idct32(subbuffer[chan], audio_buffer[chan] + audio_buffer_pos[chan]); + resynthesis(audio_buffer[chan] + audio_buffer_pos[chan] + 16, resynthesis_buffer); + scale_and_clamp(resynthesis_buffer, output + chan, channel_count); + audio_buffer_pos[chan] -= 32; + if(audio_buffer_pos[chan]<0) { + memmove(audio_buffer[chan]+17*32, audio_buffer[chan], 15*32*sizeof(audio_buffer[chan][0])); + audio_buffer_pos[chan] = 16*32; + } + } + output += 32*channel_count; + output_samples += 32; + frame_number++; + if(frame_number == last_frame_number) + return; + } + } +} + +const int mpeg_audio::sample_rates[8] = { 44100, 48000, 32000, 0, 22050, 24000, 16000, 0 }; + +const int mpeg_audio::layer2_param_index[2][4][16] = { + { + { 1, 2, 2, 0, 0, 0, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1 }, + { 0, 2, 2, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -1, -1, -1 }, + { 1, 3, 3, 0, 0, 0, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1 }, + { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 }, + }, + { + { 1, -1, -1, -1, 2, -1, 2, 0, 0, 0, 1, 1, 1, 1, 1, -1 }, + { 0, -1, -1, -1, 2, -1, 2, 0, 0, 0, 0, 0, 0, 0, 0, -1 }, + { 1, -1, -1, -1, 3, -1, 3, 0, 0, 0, 1, 1, 1, 1, 1, -1 }, + { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 }, + } +}; + +const int mpeg_audio::band_parameter_indexed_values[5][32][17] = { + { + { 0, 1, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, -1, }, + { 0, 1, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, -1, }, + { 0, 1, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + }, + { + { 0, 1, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, -1, }, + { 0, 1, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, -1, }, + { 0, 1, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 17, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + }, + { + { 0, 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + }, + { + { 0, 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + }, + { + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, -1, }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, 5, 6, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, 1, 2, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }, + } +}; + +const int mpeg_audio::band_parameter_index_bits_count[5][32] = { + { 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 0, 0, 0, 0, 0, }, + { 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2, 0, 0, }, + { 4, 4, 3, 3, 3, 3, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, + { 4, 4, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, + { 4, 4, 4, 4, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 0, }, +}; + +const int mpeg_audio::total_band_counts[5] = { 27, 30, 8, 12, 30 }; + +const int mpeg_audio::joint_band_counts[4] = { 4, 8, 12, 16 }; + +const mpeg_audio::band_info mpeg_audio::band_infos[18] = { + { 0x0000, 0.00, 0, 0, 0, 0, 0, 0, 0, 0 }, + { 0x0003, 7.00, 2, 5, 3, 9, 1-1.0/ 4, -1.0/ 4, 1/(1-1.0/ 4), 1.0/ 2 }, + { 0x0005, 11.00, 3, 7, 5, 25, 1-3.0/ 8, -3.0/ 8, 1/(1-3.0/ 8), 1.0/ 2 }, + { 0x0007, 16.00, 3, 9, 0, 0, 1-1.0/ 8, -1.0/ 8, 1/(1-1.0/ 8), 1.0/ 4 }, + { 0x0009, 20.84, 4, 10, 9, 81, 1-7.0/ 16, -7.0/ 16, 1/(1-7.0/ 16), 1.0/ 2 }, + { 0x000f, 25.28, 4, 12, 0, 0, 1-1.0/ 16, -1.0/ 16, 1/(1-1.0/ 16), 1.0/ 8 }, + { 0x001f, 31.59, 5, 15, 0, 0, 1-1.0/ 32, -1.0/ 32, 1/(1-1.0/ 32), 1.0/ 16 }, + { 0x003f, 37.75, 6, 18, 0, 0, 1-1.0/ 64, -1.0/ 64, 1/(1-1.0/ 64), 1.0/ 32 }, + { 0x007f, 43.84, 7, 21, 0, 0, 1-1.0/ 128, -1.0/ 128, 1/(1-1.0/ 128), 1.0/ 64 }, + { 0x00ff, 49.89, 8, 24, 0, 0, 1-1.0/ 256, -1.0/ 256, 1/(1-1.0/ 256), 1.0/ 128 }, + { 0x01ff, 55.93, 9, 27, 0, 0, 1-1.0/ 512, -1.0/ 512, 1/(1-1.0/ 512), 1.0/ 256 }, + { 0x03ff, 61.96, 10, 30, 0, 0, 1-1.0/ 1024, -1.0/ 1024, 1/(1-1.0/ 1024), 1.0/ 512 }, + { 0x07ff, 67.98, 11, 33, 0, 0, 1-1.0/ 2048, -1.0/ 2048, 1/(1-1.0/ 2048), 1.0/ 1024 }, + { 0x0fff, 74.01, 12, 36, 0, 0, 1-1.0/ 4096, -1.0/ 4096, 1/(1-1.0/ 4096), 1.0/ 2048 }, + { 0x1fff, 80.03, 13, 39, 0, 0, 1-1.0/ 8192, -1.0/ 8192, 1/(1-1.0/ 8192), 1.0/ 4096 }, + { 0x3fff, 86.05, 14, 42, 0, 0, 1-1.0/16384, -1.0/16384, 1/(1-1.0/16384), 1.0/ 8192 }, + { 0x7fff, 92.01, 15, 45, 0, 0, 1-1.0/32768, -1.0/32768, 1/(1-1.0/32768), 1.0/16384 }, + { 0xffff, 98.01, 16, 48, 0, 0, 1-1.0/65536, -1.0/65536, 1/(1-1.0/65536), 1.0/32768 }, +}; + +const double mpeg_audio::scalefactors[64] = { + 2.00000000000000, 1.58740105196820, 1.25992104989487, 1.00000000000000, + 0.79370052598410, 0.62996052494744, 0.50000000000000, 0.39685026299205, + 0.31498026247372, 0.25000000000000, 0.19842513149602, 0.15749013123686, + 0.12500000000000, 0.09921256574801, 0.07874506561843, 0.06250000000000, + 0.04960628287401, 0.03937253280921, 0.03125000000000, 0.02480314143700, + 0.01968626640461, 0.01562500000000, 0.01240157071850, 0.00984313320230, + 0.00781250000000, 0.00620078535925, 0.00492156660115, 0.00390625000000, + 0.00310039267963, 0.00246078330058, 0.00195312500000, 0.00155019633981, + 0.00123039165029, 0.00097656250000, 0.00077509816991, 0.00061519582514, + 0.00048828125000, 0.00038754908495, 0.00030759791257, 0.00024414062500, + 0.00019377454248, 0.00015379895629, 0.00012207031250, 0.00009688727124, + 0.00007689947814, 0.00006103515625, 0.00004844363562, 0.00003844973907, + 0.00003051757812, 0.00002422181781, 0.00001922486954, 0.00001525878906, + 0.00001211090890, 0.00000961243477, 0.00000762939453, 0.00000605545445, + 0.00000480621738, 0.00000381469727, 0.00000302772723, 0.00000240310869, + 0.00000190734863, 0.00000151386361, 0.00000120155435, 0.00000000000000 +}; + +const double mpeg_audio::synthesis_filter[512] = { + +0.000000000, -0.000015259, -0.000015259, -0.000015259, -0.000015259, -0.000015259, -0.000015259, -0.000030518, + -0.000030518, -0.000030518, -0.000030518, -0.000045776, -0.000045776, -0.000061035, -0.000061035, -0.000076294, + -0.000076294, -0.000091553, -0.000106812, -0.000106812, -0.000122070, -0.000137329, -0.000152588, -0.000167847, + -0.000198364, -0.000213623, -0.000244141, -0.000259399, -0.000289917, -0.000320435, -0.000366211, -0.000396729, + -0.000442505, -0.000473022, -0.000534058, -0.000579834, -0.000625610, -0.000686646, -0.000747681, -0.000808716, + -0.000885010, -0.000961304, -0.001037598, -0.001113892, -0.001205444, -0.001296997, -0.001388550, -0.001480103, + -0.001586914, -0.001693726, -0.001785278, -0.001907349, -0.002014160, -0.002120972, -0.002243042, -0.002349854, + -0.002456665, -0.002578735, -0.002685547, -0.002792358, -0.002899170, -0.002990723, -0.003082275, -0.003173828, + +0.003250122, +0.003326416, +0.003387451, +0.003433228, +0.003463745, +0.003479004, +0.003479004, +0.003463745, + +0.003417969, +0.003372192, +0.003280640, +0.003173828, +0.003051758, +0.002883911, +0.002700806, +0.002487183, + +0.002227783, +0.001937866, +0.001617432, +0.001266479, +0.000869751, +0.000442505, -0.000030518, -0.000549316, + -0.001098633, -0.001693726, -0.002334595, -0.003005981, -0.003723145, -0.004486084, -0.005294800, -0.006118774, + -0.007003784, -0.007919312, -0.008865356, -0.009841919, -0.010848999, -0.011886597, -0.012939453, -0.014022827, + -0.015121460, -0.016235352, -0.017349243, -0.018463135, -0.019577026, -0.020690918, -0.021789550, -0.022857666, + -0.023910522, -0.024932861, -0.025909424, -0.026840210, -0.027725220, -0.028533936, -0.029281616, -0.029937744, + -0.030532837, -0.031005860, -0.031387330, -0.031661987, -0.031814575, -0.031845093, -0.031738280, -0.031478880, + +0.031082153, +0.030517578, +0.029785156, +0.028884888, +0.027801514, +0.026535034, +0.025085450, +0.023422241, + +0.021575928, +0.019531250, +0.017257690, +0.014801025, +0.012115479, +0.009231567, +0.006134033, +0.002822876, + -0.000686646, -0.004394531, -0.008316040, -0.012420654, -0.016708374, -0.021179200, -0.025817871, -0.030609130, + -0.035552980, -0.040634155, -0.045837402, -0.051132202, -0.056533813, -0.061996460, -0.067520140, -0.073059080, + -0.078628540, -0.084182740, -0.089706420, -0.095169070, -0.100540160, -0.105819700, -0.110946655, -0.115921020, + -0.120697020, -0.125259400, -0.129562380, -0.133590700, -0.137298580, -0.140670780, -0.143676760, -0.146255500, + -0.148422240, -0.150115970, -0.151306150, -0.151962280, 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unsigned char *data, int &pos, int count) +{ + int v = 0; + for(int i=0; i != count; i++) { + v <<= 1; + if(data[pos >> 3] & (0x01 << (pos & 7))) + v |= 1; + pos++; + } + return v; +} + +int mpeg_audio::get_band_param(int band) +{ + int bit_count = band_parameter_index_bits_count[param_index][band]; + int index = gb(bit_count); + return band_parameter_indexed_values[param_index][band][index]; +} + +void mpeg_audio::read_band_params() +{ + int band = 0; + + while(band < joint_bands) { + for(int chan=0; chan < channel_count; chan++) + band_param[chan][band] = get_band_param(band); + band++; + } + + while(band < total_bands) { + int val = get_band_param(band); + band_param[0][band] = val; + band_param[1][band] = val; + band++; + } + + while(band < 32) { + band_param[0][band] = 0; + band_param[1][band] = 0; + band++; + } +} + +void mpeg_audio::read_scfci() +{ + memset(scfsi, 0, sizeof(scfsi)); + for(int band=0; band < total_bands; band++) + for(int chan=0; chan < channel_count; chan++) + if(band_param[chan][band]) + scfsi[chan][band] = gb(2); +} + +void mpeg_audio::read_band_amplitude_params() +{ + memset(scf, 0, sizeof(scf)); + for(int band=0; band < total_bands; band++) + for(int chan=0; chan<channel_count; chan++) + if(band_param[chan][band]) { + switch(scfsi[chan][band]) { + case 0: + scf[chan][0][band] = gb(6); + scf[chan][1][band] = gb(6); + scf[chan][2][band] = gb(6); + break; + + case 1: { + int val = gb(6); + scf[chan][0][band] = val; + scf[chan][1][band] = val; + scf[chan][2][band] = gb(6); + break; + } + + case 2: { + int val = gb(6); + scf[chan][0][band] = val; + scf[chan][1][band] = val; + scf[chan][2][band] = val; + break; + } + + case 3: { + scf[chan][0][band] = gb(6); + int val = gb(6); + scf[chan][1][band] = val; + scf[chan][2][band] = val; + break; + } + } + } +} + +void mpeg_audio::build_amplitudes() +{ + memset(amp_values, 0, sizeof(amp_values)); + + for(int band=0; band < total_bands; band++) + for(int chan=0; chan<channel_count; chan++) + if(band_param[chan][band]) + for(int step=0; step<3; step++) + amp_values[chan][step][band] = scalefactors[scf[chan][step][band]]; +} + +void mpeg_audio::read_band_value_triplet(int chan, int band) +{ + double buffer[3]; + + int band_idx = band_param[chan][band]; + switch(band_idx) { + case 0: + bdata[chan][0][band] = 0; + bdata[chan][1][band] = 0; + bdata[chan][2][band] = 0; + return; + + case 1: + case 2: + case 4: { + int modulo = band_infos[band_idx].modulo; + int val = gb(band_infos[band_idx].cube_bits); + buffer[0] = val % modulo; + val = val / modulo; + buffer[1] = val % modulo; + val = val / modulo; + buffer[2] = val % modulo; + break; + } + + default: { + int bits = band_infos[band_idx].bits; + buffer[0] = gb(bits); + buffer[1] = gb(bits); + buffer[2] = gb(bits); + break; + } + } + + double scale = 1 << (band_infos[band_idx].bits - 1); + + bdata[chan][0][band] = ((buffer[0] - scale) / scale + band_infos[band_idx].offset) * band_infos[band_idx].scale; + bdata[chan][1][band] = ((buffer[1] - scale) / scale + band_infos[band_idx].offset) * band_infos[band_idx].scale; + bdata[chan][2][band] = ((buffer[2] - scale) / scale + band_infos[band_idx].offset) * band_infos[band_idx].scale; +} + +void mpeg_audio::build_next_segments(int step) +{ + int band = 0; + while(band < joint_bands) { + for(int chan=0; chan<channel_count; chan++) { + read_band_value_triplet(chan, band); + double amp = amp_values[chan][step][band]; + bdata[chan][0][band] *= amp; + bdata[chan][1][band] *= amp; + bdata[chan][2][band] *= amp; + } + band++; + } + + while(band < joint_bands) { + read_band_value_triplet(0, band); + bdata[1][0][band] = bdata[0][0][band]; + bdata[1][1][band] = bdata[0][1][band]; + bdata[1][2][band] = bdata[0][2][band]; + + for(int chan=0; chan<channel_count; chan++) { + double amp = amp_values[chan][step][band]; + bdata[chan][0][band] *= amp; + bdata[chan][1][band] *= amp; + bdata[chan][2][band] *= amp; + } + band++; + } + + while(band < 32) { + bdata[0][0][band] = 0; + bdata[0][1][band] = 0; + bdata[0][2][band] = 0; + bdata[1][0][band] = 0; + bdata[1][1][band] = 0; + bdata[1][2][band] = 0; + band++; + } +} + +void mpeg_audio::retrieve_subbuffer(int step) +{ + for(int chan=0; chan<channel_count; chan++) + memcpy(subbuffer[chan], bdata[chan][step], 32*sizeof(subbuffer[0][0])); +} + +void mpeg_audio::idct32(const double *input, double *output) +{ + // Simplest idct32 ever, non-fast at all + for(int i=0; i<32; i++) { + double s = 0; + for(int j=0; j<32; j++) + s += input[j] * cos(i*(2*j+1)*M_PI/64); + output[i] = s; + } +} + +void mpeg_audio::resynthesis(const double *input, double *output) +{ + memset(output, 0, 32*sizeof(output[0])); + for(int j=0; j<64*8; j+=64) { + for(int i=0; i<16; i++) + output[i] += input[ i+j]*synthesis_filter[i+j] - input[32-i+j]*synthesis_filter[32+i+j]; + output[16] -= input[16+j]*synthesis_filter[32+16+j]; + for(int i=17; i<32; i++) + output[i] -= input[32-i+j]*synthesis_filter[i+j] + input[ i+j]*synthesis_filter[32+i+j]; + } +} + +void mpeg_audio::scale_and_clamp(const double *input, short *output, int step) +{ + for(int i=0; i<32; i++) { + double val = input[i]*32768 + 0.5; + short cval; + if(val <= -32768) + cval = -32768; + else if(val >= 32767) + cval = 32767; + else + cval = int(val); + *output = cval; + output += step; + } +} |