--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/decoders/mpglib/mpglib_common.c	Mon Mar 25 20:51:32 2002 +0000
@@ -0,0 +1,246 @@
+#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 mpglib_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 /= mpglib_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 /= mpglib_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 /= mpglib_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],mpglib_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],
+		mpglib_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;
+}
+
+
+