#include "MP3Header.h" #include "global.h" #include "nmrCommon/stl/stringUtils.h" #include "nmrCommon/services/stdServiceImpl.h" #include "nmrCommon/unicode/uniString.h" const __uint32 make28BitValue(const __uint8 buf[4]) { return ((((__uint32)buf[0]) << 21) | (((__uint32)buf[1]) << 14) | (((__uint32)buf[2]) << 7) | (((__uint32)buf[3]))); } // Bitrates - use [version][layer][bitrate] const __uint16 mpeg_bitrates[4][4][16] = { { // Version 2.5 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, // Reserved { 0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0 }, // Layer 3 { 0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0 }, // Layer 2 { 0, 32, 48, 56, 64, 80, 96, 112, 128, 144, 160, 176, 192, 224, 256, 0 } // Layer 1 }, { // Reserved { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, // Invalid { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, // Invalid { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, // Invalid { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 } // Invalid }, { // Version 2 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, // Reserved { 0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0 }, // Layer 3 { 0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0 }, // Layer 2 { 0, 32, 48, 56, 64, 80, 96, 112, 128, 144, 160, 176, 192, 224, 256, 0 } // Layer 1 }, { // Version 1 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, // Reserved { 0, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 0 }, // Layer 3 { 0, 32, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 384, 0 }, // Layer 2 { 0, 32, 64, 96, 128, 160, 192, 224, 256, 288, 320, 352, 384, 416, 448, 0 }, // Layer 1 } }; // Sample rates - use [version][srate] const __uint16 mpeg_srates[4][4] = { { 11025, 12000, 8000, 0 }, // MPEG 2.5 { 0, 0, 0, 0 }, // Reserved { 22050, 24000, 16000, 0 }, // MPEG 2 { 44100, 48000, 32000, 0 } // MPEG 1 }; // Samples per frame - use [version][layer] const __uint16 mpeg_frame_samples[4][4] = { // Rsvd 3 2 1 < Layer v Version { 0, 576, 1152, 384 }, // 2.5 { 0, 0, 0, 0 }, // Reserved { 0, 576, 1152, 384 }, // 2 { 0, 1152, 1152, 384 } // 1 }; // Slot size (MPEG unit of measurement) - use [layer] const __uint8 mpeg_slot_size[4] = { 0, 1, 1, 4 }; // Rsvd, 3, 2, 1 const char *MP3_FrameInfo::getLayerName() const { switch (m_layer) { case 1: return "3"; case 2: return "2"; case 3: return "1"; } return "unknown layer"; } const char *MP3_FrameInfo::getVersionName() const { switch (m_version) { case 0: return "v2.5"; case 2: return "v2"; case 3: return "v1"; } return "unknown version"; } int getMP3FrameSize (MP3_FrameInfo &info, const unsigned char *hdr, unsigned int len) { if (len < 4) return 0; int samples = mpeg_frame_samples[info.m_version][info.m_layer]; if (samples == 0) return -1; int bitrate = mpeg_bitrates [info.m_version] [info.m_layer] [((hdr[2] & 0xf0) >> 4)]; if (bitrate == 0) return -1; info.m_bitrate = bitrate; info.m_samples = samples; return (int)(((float)(samples / 8.0) * (float)bitrate * 1000) / (float)info.m_samplerate) + (((hdr[2] & 0x02) >> 1) ? mpeg_slot_size[info.m_layer] : 0); } const int getMP3FrameInfo(const char *hdr, unsigned int *samplerate, int *bitrate, bool *mono) { // Quick validity check if ( ( ((unsigned char)hdr[0] & 0xFF) != 0xFF) || ( ((unsigned char)hdr[1] & 0xE0) != 0xE0) // 3 sync bits || ( ((unsigned char)hdr[1] & 0x18) == 0x08) // Version rsvd || ( ((unsigned char)hdr[1] & 0x06) == 0x00) // Layer rsvd || ( ((unsigned char)hdr[2] & 0xF0) == 0xF0) // Bitrate rsvd ) return 0; // Data to be extracted from the header __uint8 ver = (hdr[1] & 0x18) >> 3; // Version index __uint8 lyr = (hdr[1] & 0x06) >> 1; // Layer index //__uint8 pad = (hdr[2] & 0x02) >> 1; // Padding? 0/1 //__uint8 brx = (hdr[2] & 0xf0) >> 4; // Bitrate index __uint8 srx = (hdr[2] & 0x0c) >> 2; // SampRate index if (mono) { *mono = (((hdr[3] >> 6) & 3) == 0x3); // Channel mode } // Lookup real values of these fields *samplerate = mpeg_srates[ver][srx]; *bitrate = mpeg_bitrates[ver][lyr][((hdr[2] & 0xf0) >> 4)]; //__uint16 samples = mpeg_frame_samples[ver][lyr]; //__uint8 slot_size = mpeg_slot_size[lyr]; // Frame sizes are truncated integers return (__uint16)(((float)(mpeg_frame_samples[ver][lyr] / 8.0) * (float)*bitrate * 1000) / (float)mpeg_srates[ver][srx]) + (((hdr[2] & 0x02) >> 1) ? mpeg_slot_size[lyr] : 0); } const int getMP3FrameInfo (const unsigned char *hdr, unsigned int len, MP3_FrameInfo &info) { // Quick validity check if ( len < 4 || ( ((unsigned char)hdr[0] & 0xFF) != 0xFF) || ( ((unsigned char)hdr[1] & 0xE0) != 0xE0) // 3 sync bits || ( ((unsigned char)hdr[1] & 0x18) == 0x08) // Version rsvd || ( ((unsigned char)hdr[1] & 0x06) == 0x00) // Layer rsvd || ( ((unsigned char)hdr[2] & 0xF0) == 0xF0) // Bitrate rsvd ) return -1; // Data to be extracted from the header __uint8 ver = (hdr[1] & 0x18) >> 3; // Version index __uint8 lyr = (hdr[1] & 0x06) >> 1; // Layer index __uint8 srx = (hdr[2] & 0x0c) >> 2; // SampRate index do { // Lookup real values of these fields unsigned int samplerate = mpeg_srates [ver][srx]; if (samplerate == 0) break; int bitrate = mpeg_bitrates [ver][lyr][((hdr[2] & 0xf0) >> 4)]; if (bitrate == 0) break; info.m_bitrate = bitrate; // the following are not supposed to change info.m_samplerate = samplerate; info.m_mono = (((hdr[3] >> 6) & 3) == 0x3); // Channel mode info.m_layer = lyr; // Layer index info.m_version = ver; if (info.m_pattern == 0) info.m_pattern = (unsigned long)(hdr[0]<<24 | (hdr[1]<<16) | (hdr[2]<<8) | hdr[0]) & info.m_mask; // DLOG (uniString::utf8("MPEG ") + info.getVersionName() + " layer " + info.getLayerName() + (info.m_mono ? " mono (" : " stereo (") + stringUtil::tos(bitrate) + "k)"); return getMP3FrameSize (info, hdr, 4); } while (0); return -1; } int MP3_FrameInfo::verifyFrame (const unsigned char *buf, unsigned int len) { if (len > 4) { unsigned long v = (unsigned long)(buf[0])<<24 | (buf[1]<<16) | (buf[2]<<8) | buf[0]; if ((v & m_mask) == m_pattern) { #if 0 if (len > 40) { unsigned char str[6] = "LAME"; int i; for (i=0; i < 5 && buf[36+i] == str[i]; i++) ; if (str[i] == '\0') DLOG ("LAME header found"); } #endif return getMP3FrameSize (*this, buf, len); } // DLOG ("MPG: mask is " + stringUtil::tos(v&m_mask) + ", patt " + stringUtil::tos(m_pattern)); return -1; } return 0; } MP3_FrameInfo::MP3_FrameInfo (unsigned long value) : parserInfo (0xFFFE0000, value) { m_description = "MPEG "; } MP3_FrameInfo::MP3_FrameInfo(const unsigned char *p, unsigned int len) : parserInfo() { m_mask = 0xFFFE0000; m_description = "MPEG "; getMP3FrameInfo (p, len, *this); }