/*************************************************************************** * __________ __ ___. * Open \______ \ ____ ____ | | _\_ |__ _______ ___ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ * \/ \/ \/ \/ \/ * $Id$ * * Copyright (C) 2005 Thom Johansen * Copyright (C) 2010 Andree Buschmann * * 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 2 * of the License, or (at your option) any later version. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ****************************************************************************/ #include #include #include "system.h" #include "metadata.h" #include "metadata_common.h" #include "metadata_parsers.h" #include "logf.h" #include "replaygain.h" #include "fixedpoint.h" /* Needed for replay gain and clipping prevention of SV8 files. */ #define SV8_TO_SV7_CONVERT_GAIN (6482) /* 64.82 * 100, MPC_OLD_GAIN_REF */ #define SV8_TO_SV7_CONVERT_PEAK (23119) /* 256 * 20 * log10(32768) */ static int set_replaygain_sv7(struct mp3entry* id3, bool album, long value, long used) { long gain = (int16_t) ((value >> 16) & 0xffff); long peak = (uint16_t) (value & 0xffff); /* We use a peak value of 0 to indicate a given gain type isn't used. */ if (peak != 0) { /* Save the ReplayGain data to id3-structure for further processing. */ used += parse_replaygain_int(album, gain * 512 / 100, peak << 9, id3, id3->toc + used, sizeof(id3->toc) - used); } return used; } static int set_replaygain_sv8(struct mp3entry* id3, bool album, long gain, long peak, long used) { gain = (long)(SV8_TO_SV7_CONVERT_GAIN - ((gain*100)/256)); /* Transform SV8's logarithmic peak representation to the desired linear * representation: linear = pow(10, peak/256/20). * * FP_BITS = 24 bits = desired fp representation for dsp routines * FRAC_BITS = 12 bits = resolution used for fp_bits * fp_factor(peak*(1<toc + used, sizeof(id3->toc) - used); } return used; } static int sv8_get_size(uint8_t *buffer, int index, uint64_t *p_size) { unsigned char tmp; uint64_t size = 0; do { tmp = buffer[index++]; size = (size << 7) | (tmp & 0x7F); } while((tmp & 0x80)); *p_size = size; return index; } bool get_musepack_metadata(int fd, struct mp3entry *id3) { static const int32_t sfreqs[4] = { 44100, 48000, 37800, 32000 }; uint32_t header[8]; uint64_t samples = 0; int i; if (!skip_id3v2(fd, id3)) return false; if (read(fd, header, 4*8) != 4*8) return false; /* Musepack files are little endian, might need swapping */ for (i = 1; i < 8; i++) header[i] = letoh32(header[i]); if (!memcmp(header, "MP+", 3)) { /* Compare to sig "MP+" */ unsigned int streamversion; header[0] = letoh32(header[0]); streamversion = (header[0] >> 24) & 15; if (streamversion == 7) { unsigned int gapless = (header[5] >> 31) & 0x0001; unsigned int last_frame_samples = (header[5] >> 20) & 0x07ff; unsigned int bufused = 0; id3->frequency = sfreqs[(header[2] >> 16) & 0x0003]; samples = (uint64_t)header[1]*1152; /* 1152 is mpc frame size */ if (gapless) samples -= 1152 - last_frame_samples; else samples -= 481; /* Musepack subband synth filter delay */ bufused = set_replaygain_sv7(id3, false, header[3], bufused); bufused = set_replaygain_sv7(id3, true , header[4], bufused); } else { return false; /* only SV7 is allowed within a "MP+" signature */ } } else if (!memcmp(header, "MPCK", 4)) { /* Compare to sig "MPCK" */ uint8_t sv8_header[32]; /* 4 bytes 'MPCK' */ lseek(fd, 4, SEEK_SET); if (read(fd, sv8_header, 2) != 2) return false; /* read frame ID */ if (!memcmp(sv8_header, "SH", 2)) { /* Stream Header ID */ int32_t k = 0; uint32_t streamversion; uint64_t size = 0; /* tag size */ uint64_t dummy = 0; /* used to dummy read data from header */ /* 4 bytes 'MPCK' + 2 'SH' */ lseek(fd, 6, SEEK_SET); if (read(fd, sv8_header, 32) != 32) return false; /* Read the size of 'SH'-tag */ k = sv8_get_size(sv8_header, k, &size); /* Skip crc32 */ k += 4; /* Read stream version */ streamversion = sv8_header[k++]; if (streamversion != 8) return false; /* Only SV8 is allowed. */ /* Number of samples */ k = sv8_get_size(sv8_header, k, &samples); /* Number of leading zero-samples */ k = sv8_get_size(sv8_header, k, &dummy); /* Sampling frequency */ id3->frequency = sfreqs[(sv8_header[k++] >> 5) & 0x0003]; /* Number of channels */ id3->channels = (sv8_header[k++] >> 4) + 1; /* Skip to next tag: k = size -2 */ k = size - 2; if (!memcmp(sv8_header+k, "RG", 2)) { /* Replay Gain ID */ long peak, gain; int bufused = 0; k += 2; /* 2 bytes 'RG' */ /* sv8_get_size must be called to skip the right amount of * bits within the header data. */ k = sv8_get_size(sv8_header, k, &size); /* Read and set replay gain */ if (sv8_header[k++] == 1) { /* Title's peak and gain */ gain = (int16_t) ((sv8_header[k]<<8) + sv8_header[k+1]); k += 2; peak = (uint16_t)((sv8_header[k]<<8) + sv8_header[k+1]); k += 2; bufused += set_replaygain_sv8(id3, false, gain, peak, bufused); /* Album's peak and gain */ gain = (int16_t) ((sv8_header[k]<<8) + sv8_header[k+1]); k += 2; peak = (uint16_t)((sv8_header[k]<<8) + sv8_header[k+1]); k += 2; bufused += set_replaygain_sv8(id3, true , gain, peak, bufused); } } } else { /* No sv8 stream header found */ return false; } } else { return false; /* SV4-6 is not supported anymore */ } id3->vbr = true; /* Estimate bitrate, we should probably subtract the various header sizes here for super-accurate results */ id3->length = ((int64_t) samples * 1000) / id3->frequency; if (id3->length <= 0) { logf("mpc length invalid!"); return false; } id3->filesize = filesize(fd); id3->bitrate = id3->filesize * 8 / id3->length; return true; }