// Reference: DOCS/tech/hwac3.txt !!!!! /* DTS code based on "ac3/decode_dts.c" and "ac3/conversion.c" from "ogle 0.9" (see http://www.dtek.chalmers.se/~dvd/) */ #include #include #include #include #include "config.h" #ifdef USE_LIBA52 #include "mp_msg.h" #include "help_mp.h" #include "mpbswap.h" #include "ad_internal.h" #include "liba52/a52.h" static int isdts = -1; static ad_info_t info = { "AC3/DTS pass-through S/PDIF", "hwac3", "Nick Kurshev/Peter Schüller", "???", "" }; LIBAD_EXTERN(hwac3) static int dts_syncinfo(uint8_t *indata_ptr, int *flags, int *sample_rate, int *bit_rate); static int decode_audio_dts(unsigned char *indata_ptr, int len, unsigned char *buf); static int ac3dts_fillbuff(sh_audio_t *sh_audio) { int length = 0; int flags = 0; int sample_rate = 0; int bit_rate = 0; sh_audio->a_in_buffer_len = 0; /* sync frame:*/ while(1) { // DTS has a 10 byte header while(sh_audio->a_in_buffer_len < 10) { int c = demux_getc(sh_audio->ds); if(c<0) return -1; /* EOF*/ sh_audio->a_in_buffer[sh_audio->a_in_buffer_len++] = c; } length = dts_syncinfo(sh_audio->a_in_buffer, &flags, &sample_rate, &bit_rate); if(length >= 10) { if(isdts != 1) { mp_msg(MSGT_DECAUDIO, MSGL_STATUS, "hwac3: switched to DTS, %d bps, %d Hz\n", bit_rate, sample_rate); isdts = 1; } break; } length = a52_syncinfo(sh_audio->a_in_buffer, &flags, &sample_rate, &bit_rate); if(length >= 7 && length <= 3840) { if(isdts != 0) { mp_msg(MSGT_DECAUDIO, MSGL_STATUS, "hwac3: switched to AC3, %d bps, %d Hz\n", bit_rate, sample_rate); isdts = 0; } break; /* we're done.*/ } /* bad file => resync*/ memcpy(sh_audio->a_in_buffer, sh_audio->a_in_buffer + 1, 9); --sh_audio->a_in_buffer_len; } mp_msg(MSGT_DECAUDIO, MSGL_DBG2, "ac3dts: %s len=%d flags=0x%X %d Hz %d bit/s\n", isdts == 1 ? "DTS" : isdts == 0 ? "AC3" : "unknown", length, flags, sample_rate, bit_rate); sh_audio->samplerate = sample_rate; sh_audio->i_bps = bit_rate / 8; demux_read_data(sh_audio->ds, sh_audio->a_in_buffer + 10, length - 10); sh_audio->a_in_buffer_len = length; // TODO: is DTS also checksummed? if(isdts == 0 && crc16_block(sh_audio->a_in_buffer + 2, length - 2) != 0) mp_msg(MSGT_DECAUDIO, MSGL_STATUS, "a52: CRC check failed! \n"); return length; } static int preinit(sh_audio_t *sh) { /* Dolby AC3 audio: */ sh->audio_out_minsize = 128 * 32 * 2 * 2; // DTS seems to need more than AC3 sh->audio_in_minsize = 8192; sh->channels = 2; sh->samplesize = 2; sh->sample_format = AF_FORMAT_AC3; return 1; } static int init(sh_audio_t *sh_audio) { /* Dolby AC3 passthrough:*/ a52_state_t *a52_state = a52_init(0); if(a52_state == NULL) { mp_msg(MSGT_DECAUDIO, MSGL_ERR, "A52 init failed\n"); return 0; } if(ac3dts_fillbuff(sh_audio) < 0) { mp_msg(MSGT_DECAUDIO, MSGL_ERR, "AC3/DTS sync failed\n"); return 0; } return 1; } static void uninit(sh_audio_t *sh) { } static int control(sh_audio_t *sh,int cmd,void* arg, ...) { switch(cmd) { case ADCTRL_RESYNC_STREAM: case ADCTRL_SKIP_FRAME: ac3dts_fillbuff(sh); return CONTROL_TRUE; } return CONTROL_UNKNOWN; } static int decode_audio(sh_audio_t *sh_audio,unsigned char *buf,int minlen,int maxlen) { int len = sh_audio->a_in_buffer_len; if(len <= 0) if((len = ac3dts_fillbuff(sh_audio)) <= 0) return len; /*EOF*/ sh_audio->a_in_buffer_len = 0; if(isdts == 1) { return decode_audio_dts(sh_audio->a_in_buffer, len, buf); } else if(isdts == 0) { uint16_t *buf16 = (uint16_t *)buf; buf16[0] = 0xF872; // iec 61937 syncword 1 buf16[1] = 0x4E1F; // iec 61937 syncword 2 buf16[2] = 0x0001; // data-type ac3 buf16[3] = len << 3; // number of bits in payload #ifdef WORDS_BIGENDIAN memcpy(buf + 8, sh_audio->a_in_buffer, len); #else swab(sh_audio->a_in_buffer, buf + 8, len); #endif memset(buf + 8 + len, 0, 6144 - 8 - len); return 6144; } else return -1; } static int DTS_SAMPLEFREQS[16] = { 0, 8000, 16000, 32000, 64000, 128000, 11025, 22050, 44100, 88200, 176400, 12000, 24000, 48000, 96000, 192000 }; static int DTS_BITRATES[30] = { 32000, 56000, 64000, 96000, 112000, 128000, 192000, 224000, 256000, 320000, 384000, 448000, 512000, 576000, 640000, 768000, 896000, 1024000, 1152000, 1280000, 1344000, 1408000, 1411200, 1472000, 1536000, 1920000, 2048000, 3072000, 3840000, 4096000 }; static int dts_decode_header(uint8_t *indata_ptr, int *rate, int *nblks, int *sfreq) { int ftype; int surp; int unknown_bit; int fsize; int amode; if(((indata_ptr[0] << 24) | (indata_ptr[1] << 16) | (indata_ptr[2] << 8) | (indata_ptr[3])) != 0x7ffe8001) return -1; ftype = indata_ptr[4] >> 7; surp = (indata_ptr[4] >> 2) & 0x1f; surp = (surp + 1) % 32; unknown_bit = (indata_ptr[4] >> 1) & 0x01; *nblks = (indata_ptr[4] & 0x01) << 6 | (indata_ptr[5] >> 2); *nblks = *nblks + 1; fsize = (indata_ptr[5] & 0x03) << 12 | (indata_ptr[6] << 4) | (indata_ptr[7] >> 4); fsize = fsize + 1; amode = (indata_ptr[7] & 0x0f) << 2 | (indata_ptr[8] >> 6); *sfreq = (indata_ptr[8] >> 2) & 0x0f; *rate = (indata_ptr[8] & 0x03) << 3 | ((indata_ptr[9] >> 5) & 0x07); if(ftype != 1) { mp_msg(MSGT_DECAUDIO, MSGL_ERR, "DTS: Termination frames not handled, REPORT BUG\n"); return -1; } if(*sfreq != 13) { mp_msg(MSGT_DECAUDIO, MSGL_ERR, "DTS: Only 48kHz supported, REPORT BUG\n"); return -1; } if((fsize > 8192) || (fsize < 96)) { mp_msg(MSGT_DECAUDIO, MSGL_ERR, "DTS: fsize: %d invalid, REPORT BUG\n", fsize); return -1; } if(*nblks != 8 && *nblks != 16 && *nblks != 32 && *nblks != 64 && *nblks != 128 && ftype == 1) { mp_msg(MSGT_DECAUDIO, MSGL_ERR, "DTS: nblks %d not valid for normal frame, REPORT BUG\n", *nblks); return -1; } return fsize; } static int dts_syncinfo(uint8_t *indata_ptr, int *flags, int *sample_rate, int *bit_rate) { int nblks; int fsize; int rate; int sfreq; fsize = dts_decode_header(indata_ptr, &rate, &nblks, &sfreq); if(fsize >= 0) { if(rate >= 0 && rate <= 29) *bit_rate = DTS_BITRATES[rate]; else *bit_rate = 0; if(sfreq >= 1 && sfreq <= 15) *sample_rate = DTS_SAMPLEFREQS[sfreq]; else *sample_rate = 0; } return fsize; } static int decode_audio_dts(unsigned char *indata_ptr, int len, unsigned char *buf) { int nblks; int fsize; int rate; int sfreq; int burst_len; int nr_samples; uint16_t *buf16 = (uint16_t *)buf; fsize = dts_decode_header(indata_ptr, &rate, &nblks, &sfreq); if(fsize < 0) return -1; burst_len = fsize * 8; nr_samples = nblks * 32; buf16[0] = 0xf872; /* iec 61937 */ buf16[1] = 0x4e1f; /* syncword */ switch(nr_samples) { case 512: buf16[2] = 0x000b; /* DTS-1 (512-sample bursts) */ break; case 1024: buf16[2] = 0x000c; /* DTS-2 (1024-sample bursts) */ break; case 2048: buf16[2] = 0x000d; /* DTS-3 (2048-sample bursts) */ break; default: mp_msg(MSGT_DECAUDIO, MSGL_ERR, "DTS: %d-sample bursts not supported\n", nr_samples); buf16[2] = 0x0000; break; } buf16[3] = burst_len; if(fsize + 8 > nr_samples * 2 * 2) { mp_msg(MSGT_DECAUDIO, MSGL_ERR, "DTS: more data than fits\n"); } #ifdef WORDS_BIGENDIAN memcpy(&buf[8], indata_ptr, fsize); #else //TODO if fzise is odd, swab doesn't copy the last byte swab(indata_ptr, &buf[8], fsize); if (fsize & 1) buf[8+fsize] = indata_ptr[fsize]; #endif memset(&buf[fsize + 8], 0, nr_samples * 2 * 2 - (fsize + 8)); return nr_samples * 2 * 2; } #endif