Mercurial > SDL_sound_CoreAudio
view decoders/mpglib/common.c @ 278:dfe4a46f88f7
Updated.
author | Ryan C. Gordon <icculus@icculus.org> |
---|---|
date | Thu, 14 Mar 2002 16:38:32 +0000 |
parents | 9e7f9e09ea0e |
children | a9e211c3faa4 |
line wrap: on
line source
#include <ctype.h> #include <stdlib.h> #include <signal.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include "SDL_sound.h" #define __SDL_SOUND_INTERNAL__ #include "SDL_sound_internal.h" #include "mpg123_sdlsound.h" struct parameter param = { 1 , 1 , 0 , 0 }; int tabsel_123[2][3][16] = { { {0,32,64,96,128,160,192,224,256,288,320,352,384,416,448,}, {0,32,48,56, 64, 80, 96,112,128,160,192,224,256,320,384,}, {0,32,40,48, 56, 64, 80, 96,112,128,160,192,224,256,320,} }, { {0,32,48,56,64,80,96,112,128,144,160,176,192,224,256,}, {0,8,16,24,32,40,48,56,64,80,96,112,128,144,160,}, {0,8,16,24,32,40,48,56,64,80,96,112,128,144,160,} } }; long freqs[9] = { 44100, 48000, 32000, 22050, 24000, 16000 , 11025 , 12000 , 8000 }; int bitindex; unsigned char *wordpointer; unsigned char *pcm_sample; int pcm_point = 0; #define HDRCMPMASK 0xfffffd00 #if 0 int head_check(unsigned long head) { if( (head & 0xffe00000) != 0xffe00000) return FALSE; if(!((head>>17)&3)) return FALSE; if( ((head>>12)&0xf) == 0xf) return FALSE; if( ((head>>10)&0x3) == 0x3 ) return FALSE; return TRUE; } #endif /* * the code a header and write the information * into the frame structure */ int decode_header(struct frame *fr,unsigned long newhead) { if( newhead & (1<<20) ) { fr->lsf = (newhead & (1<<19)) ? 0x0 : 0x1; fr->mpeg25 = 0; } else { fr->lsf = 1; fr->mpeg25 = 1; } fr->lay = 4-((newhead>>17)&3); if( ((newhead>>10)&0x3) == 0x3) { Sound_SetError("MPGLIB: Corrupted header"); return 0; } if(fr->mpeg25) { fr->sampling_frequency = 6 + ((newhead>>10)&0x3); } else fr->sampling_frequency = ((newhead>>10)&0x3) + (fr->lsf*3); fr->error_protection = ((newhead>>16)&0x1)^0x1; if(fr->mpeg25) /* allow Bitrate change for 2.5 ... */ fr->bitrate_index = ((newhead>>12)&0xf); fr->bitrate_index = ((newhead>>12)&0xf); fr->padding = ((newhead>>9)&0x1); fr->extension = ((newhead>>8)&0x1); fr->mode = ((newhead>>6)&0x3); fr->mode_ext = ((newhead>>4)&0x3); fr->copyright = ((newhead>>3)&0x1); fr->original = ((newhead>>2)&0x1); fr->emphasis = newhead & 0x3; fr->stereo = (fr->mode == MPG_MD_MONO) ? 1 : 2; if(!fr->bitrate_index) { Sound_SetError("MPGLIB: Free format not supported."); return (0); } switch(fr->lay) { case 1: #ifdef LAYER1 #if 0 fr->jsbound = (fr->mode == MPG_MD_JOINT_STEREO) ? (fr->mode_ext<<2)+4 : 32; #endif fr->framesize = (long) tabsel_123[fr->lsf][0][fr->bitrate_index] * 12000; fr->framesize /= freqs[fr->sampling_frequency]; fr->framesize = ((fr->framesize+fr->padding)<<2)-4; #else Sound_SetError("MPGLIB: Not supported!"); #endif break; case 2: #ifdef LAYER2 #if 0 fr->jsbound = (fr->mode == MPG_MD_JOINT_STEREO) ? (fr->mode_ext<<2)+4 : fr->II_sblimit; #endif fr->framesize = (long) tabsel_123[fr->lsf][1][fr->bitrate_index] * 144000; fr->framesize /= freqs[fr->sampling_frequency]; fr->framesize += fr->padding - 4; #else Sound_SetError("MPGLIB: Not supported!"); #endif break; case 3: #if 0 fr->do_layer = do_layer3; if(fr->lsf) ssize = (fr->stereo == 1) ? 9 : 17; else ssize = (fr->stereo == 1) ? 17 : 32; #endif #if 0 if(fr->error_protection) ssize += 2; #endif fr->framesize = (long) tabsel_123[fr->lsf][2][fr->bitrate_index] * 144000; fr->framesize /= freqs[fr->sampling_frequency]<<(fr->lsf); fr->framesize = fr->framesize + fr->padding - 4; break; default: Sound_SetError("MPGLIB: Unknown layer type."); return (0); } return 1; } #if 0 void print_header(struct frame *fr) { static char *modes[4] = { "Stereo", "Joint-Stereo", "Dual-Channel", "Single-Channel" }; static char *layers[4] = { "Unknown" , "I", "II", "III" }; fprintf(stderr,"MPEG %s, Layer: %s, Freq: %ld, mode: %s, modext: %d, BPF : %d\n", fr->mpeg25 ? "2.5" : (fr->lsf ? "2.0" : "1.0"), layers[fr->lay],freqs[fr->sampling_frequency], modes[fr->mode],fr->mode_ext,fr->framesize+4); fprintf(stderr,"Channels: %d, copyright: %s, original: %s, CRC: %s, emphasis: %d.\n", fr->stereo,fr->copyright?"Yes":"No", fr->original?"Yes":"No",fr->error_protection?"Yes":"No", fr->emphasis); fprintf(stderr,"Bitrate: %d Kbits/s, Extension value: %d\n", tabsel_123[fr->lsf][fr->lay-1][fr->bitrate_index],fr->extension); } void print_header_compact(struct frame *fr) { static char *modes[4] = { "stereo", "joint-stereo", "dual-channel", "mono" }; static char *layers[4] = { "Unknown" , "I", "II", "III" }; fprintf(stderr,"MPEG %s layer %s, %d kbit/s, %ld Hz %s\n", fr->mpeg25 ? "2.5" : (fr->lsf ? "2.0" : "1.0"), layers[fr->lay], tabsel_123[fr->lsf][fr->lay-1][fr->bitrate_index], freqs[fr->sampling_frequency], modes[fr->mode]); } #endif unsigned int getbits(int number_of_bits) { unsigned long rval; if(!number_of_bits) return 0; { rval = wordpointer[0]; rval <<= 8; rval |= wordpointer[1]; rval <<= 8; rval |= wordpointer[2]; rval <<= bitindex; rval &= 0xffffff; bitindex += number_of_bits; rval >>= (24-number_of_bits); wordpointer += (bitindex>>3); bitindex &= 7; } return rval; } unsigned int getbits_fast(int number_of_bits) { unsigned long rval; { rval = wordpointer[0]; rval <<= 8; rval |= wordpointer[1]; rval <<= bitindex; rval &= 0xffff; bitindex += number_of_bits; rval >>= (16-number_of_bits); wordpointer += (bitindex>>3); bitindex &= 7; } return rval; } unsigned int get1bit(void) { unsigned char rval; rval = *wordpointer << bitindex; bitindex++; wordpointer += (bitindex>>3); bitindex &= 7; return rval>>7; }