mkxp-z/SDL2_sound/SDL_sound_shn.c

1309 lines
50 KiB
C

/**
* SDL_sound; A sound processing toolkit.
*
* Please see the file LICENSE.txt in the source's root directory.
*
* This file written by Ryan C. Gordon.
*/
/*
* Shorten decoder for SDL_sound.
*
* This driver handles Shorten-compressed waveforms. Despite the fact that
* SHNs tend to be much bigger than MP3s, they are still the de facto
* standard in online music trading communities. If an MP3 crunches the
* waveform to 10-20 percent of its original size, SHNs only go to about
* 50-60%. Why do the Phish fans of the world use this format then? Rabid
* music traders appreciate the sound quality; SHNs, unlike MP3s, do not
* throw away any part of the waveform. Yes, there are people that notice
* this, and further more, they demand it...and if they can't get a good
* transfer of those larger files over the 'net, they haven't underestimated
* the bandwidth of CDs travelling the world through the postal system.
*
* Shorten homepage: http://www.softsound.com/Shorten.html
*
* !!! FIXME: softsound.com is gone, I think.
*
* The Shorten format was gleaned from the shorten codebase, by Tony
* Robinson and SoftSound Limited.
*/
#define __SDL_SOUND_INTERNAL__
#include "SDL_sound_internal.h"
#if SOUND_SUPPORTS_SHN
#define SHN_BUFSIZ 512
typedef struct
{
Sint32 version;
Sint32 datatype;
Sint32 nchan;
Sint32 blocksize;
Sint32 maxnlpc;
Sint32 nmean;
Sint32 nwrap;
Sint32 **buffer;
Sint32 **offset;
Sint32 *qlpc;
Sint32 lpcqoffset;
Sint32 bitshift;
int nbitget;
int nbyteget;
Uint8 *getbuf;
Uint8 *getbufp;
Uint32 gbuffer;
Uint8 *backBuffer;
Uint32 backBufferSize;
Uint32 backBufLeft;
Uint32 start_pos;
} shn_t;
static const Uint32 mask_table[] =
{
0x00000000, 0x00000001, 0x00000003, 0x00000007, 0x0000000F, 0x0000001F,
0x0000003F, 0x0000007F, 0x000000FF, 0x000001FF, 0x000003FF, 0x000007FF,
0x00000FFF, 0x00001FFF, 0x00003FFF, 0x00007FFF, 0x0000FFFF, 0x0001FFFF,
0x0003FFFF, 0x0007FFFF, 0x000FFFFF, 0x001FFFFF, 0x003FFFFF, 0x007FFFFF,
0x00FFFFFF, 0x01FFFFFF, 0x03FFFFFF, 0x07FFFFFF, 0x0FFFFFFF, 0x1FFFFFFF,
0x3FFFFFFF, 0x7FFFFFFF, 0xFFFFFFFF
};
static const Uint8 ulaw_outward[13][256] = {
{127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,255,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128},
{112,114,116,118,120,122,124,126,127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,113,115,117,119,121,123,125,255,253,251,249,247,245,243,241,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128,254,252,250,248,246,244,242,240},
{96,98,100,102,104,106,108,110,112,113,114,116,117,118,120,121,122,124,125,126,127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,97,99,101,103,105,107,109,111,115,119,123,255,251,247,243,239,237,235,233,231,229,227,225,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128,254,253,252,250,249,248,246,245,244,242,241,240,238,236,234,232,230,228,226,224},
{80,82,84,86,88,90,92,94,96,97,98,100,101,102,104,105,106,108,109,110,112,113,114,115,116,117,118,120,121,122,123,124,125,126,127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,81,83,85,87,89,91,93,95,99,103,107,111,119,255,247,239,235,231,227,223,221,219,217,215,213,211,209,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128,254,253,252,251,250,249,248,246,245,244,243,242,241,240,238,237,236,234,233,232,230,229,228,226,225,224,222,220,218,216,214,212,210,208},
{64,66,68,70,72,74,76,78,80,81,82,84,85,86,88,89,90,92,93,94,96,97,98,99,100,101,102,104,105,106,107,108,109,110,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,65,67,69,71,73,75,77,79,83,87,91,95,103,111,255,239,231,223,219,215,211,207,205,203,201,199,197,195,193,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,238,237,236,235,234,233,232,230,229,228,227,226,225,224,222,221,220,218,217,216,214,213,212,210,209,208,206,204,202,200,198,196,194,192},
{49,51,53,55,57,59,61,63,64,66,67,68,70,71,72,74,75,76,78,79,80,81,82,84,85,86,87,88,89,90,92,93,94,95,96,97,98,99,100,101,102,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,50,52,54,56,58,60,62,65,69,73,77,83,91,103,255,231,219,211,205,201,197,193,190,188,186,184,182,180,178,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,230,229,228,227,226,225,224,223,222,221,220,218,217,216,215,214,213,212,210,209,208,207,206,204,203,202,200,199,198,196,195,194,192,191,189,187,185,183,181,179,177},
{32,34,36,38,40,42,44,46,48,49,51,52,53,55,56,57,59,60,61,63,64,65,66,67,68,70,71,72,73,74,75,76,78,79,80,81,82,83,84,85,86,87,88,89,90,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,33,35,37,39,41,43,45,47,50,54,58,62,69,77,91,255,219,205,197,190,186,182,178,175,173,171,169,167,165,163,161,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,218,217,216,215,214,213,212,211,210,209,208,207,206,204,203,202,201,200,199,198,196,195,194,193,192,191,189,188,187,185,184,183,181,180,179,177,176,174,172,170,168,166,164,162,160},
{16,18,20,22,24,26,28,30,32,33,34,36,37,38,40,41,42,44,45,46,48,49,50,51,52,53,55,56,57,58,59,60,61,63,64,65,66,67,68,69,70,71,72,73,74,75,76,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,17,19,21,23,25,27,29,31,35,39,43,47,54,62,77,255,205,190,182,175,171,167,163,159,157,155,153,151,149,147,145,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,204,203,202,201,200,199,198,197,196,195,194,193,192,191,189,188,187,186,185,184,183,181,180,179,178,177,176,174,173,172,170,169,168,166,165,164,162,161,160,158,156,154,152,150,148,146,144},
{2,4,6,8,10,12,14,16,17,18,20,21,22,24,25,26,28,29,30,32,33,34,35,36,37,38,40,41,42,43,44,45,46,48,49,50,51,52,53,54,55,56,57,58,59,60,61,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,1,3,5,7,9,11,13,15,19,23,27,31,39,47,62,255,190,175,167,159,155,151,147,143,141,139,137,135,133,131,129,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,189,188,187,186,185,184,183,182,181,180,179,178,177,176,174,173,172,171,170,169,168,166,165,164,163,162,161,160,158,157,156,154,153,152,150,149,148,146,145,144,142,140,138,136,134,132,130,128},
{1,2,4,5,6,8,9,10,12,13,14,16,17,18,19,20,21,22,24,25,26,27,28,29,30,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,3,7,11,15,23,31,47,255,175,159,151,143,139,135,131,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,158,157,156,155,154,153,152,150,149,148,147,146,145,144,142,141,140,138,137,136,134,133,132,130,129,128},
{1,2,3,4,5,6,8,9,10,11,12,13,14,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,7,15,31,255,159,143,135,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,142,141,140,139,138,137,136,134,133,132,131,130,129,128},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,15,255,143,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,255,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128}
};
#ifndef MIN_MACRO
#define MIN_MACRO(a,b) (((a)<(b))?(a):(b))
#endif
#ifndef MAX_MACRO
#define MAX_MACRO(a,b) (((a)>(b))?(a):(b))
#endif
#define POSITIVE_ULAW_ZERO 0xff
#define NEGATIVE_ULAW_ZERO 0x7f
#define CAPMAXSCHAR(x) ((x > 127) ? 127 : x)
#define CAPMAXUCHAR(x) ((x > 255) ? 255 : x)
#define CAPMAXSHORT(x) ((x > 32767) ? 32767 : x)
#define CAPMAXUSHORT(x) ((x > 65535) ? 65535 : x)
#define UNDEFINED_UINT -1
#define DEFAULT_BLOCK_SIZE 256
#define DEFAULT_V0NMEAN 0
#define DEFAULT_V2NMEAN 4
#define DEFAULT_MAXNLPC 0
#define DEFAULT_NCHAN 1
#define DEFAULT_NSKIP 0
#define DEFAULT_NDISCARD 0
#define NBITPERLONG 32
#define DEFAULT_MINSNR 256
#define DEFAULT_QUANTERROR 0
#define MINBITRATE 2.5
#define MEAN_VERSION0 0
#define MEAN_VERSION2 4
#define SHN_FN_DIFF0 0
#define SHN_FN_DIFF1 1
#define SHN_FN_DIFF2 2
#define SHN_FN_DIFF3 3
#define SHN_FN_QUIT 4
#define SHN_FN_BLOCKSIZE 5
#define SHN_FN_BITSHIFT 6
#define SHN_FN_QLPC 7
#define SHN_FN_ZERO 8
#define SHN_FN_VERBATIM 9
#define SHN_TYPE_AU1 0
#define SHN_TYPE_S8 1
#define SHN_TYPE_U8 2
#define SHN_TYPE_S16HL 3
#define SHN_TYPE_U16HL 4
#define SHN_TYPE_S16LH 5
#define SHN_TYPE_U16LH 6
#define SHN_TYPE_ULAW 7
#define SHN_TYPE_AU2 8
#define SHN_TYPE_AU3 9
#define SHN_TYPE_ALAW 10
#define SHN_TYPE_RIFF_WAVE 11
#define SHN_TYPE_EOF 12
#define SHN_TYPE_GENERIC_ULAW 128
#define SHN_TYPE_GENERIC_ALAW 129
#define SHN_FNSIZE 2
#define SHN_CHANNELSIZE 0
#define SHN_TYPESIZE 4
#define SHN_ULONGSIZE 2
#define SHN_NSKIPSIZE 1
#define SHN_LPCQSIZE 2
#define SHN_LPCQUANT 5
#define SHN_XBYTESIZE 7
#define SHN_VERBATIM_CKSIZE_SIZE 5
#define SHN_VERBATIM_BYTE_SIZE 8
#define SHN_ENERGYSIZE 3
#define SHN_BITSHIFTSIZE 2
#define SHN_LPCQOFFSET_VER2 (1 << SHN_LPCQUANT)
#define SHN_MAGIC 0x676B6A61 /* looks like "ajkg" as chars. */
#ifndef M_LN2
#define M_LN2 0.69314718055994530942
#endif
#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif
static int word_get(shn_t *shn, SDL_RWops *rw, Uint32 *word)
{
if (shn->nbyteget < 4)
{
shn->nbyteget += SDL_RWread(rw, shn->getbuf, 1, SHN_BUFSIZ);
BAIL_IF_MACRO(shn->nbyteget < 4, NULL, 0);
shn->getbufp = shn->getbuf;
} /* if */
if (word != NULL)
{
*word = (((Sint32) shn->getbufp[0]) << 24) |
(((Sint32) shn->getbufp[1]) << 16) |
(((Sint32) shn->getbufp[2]) << 8) |
(((Sint32) shn->getbufp[3]) );
} /* if */
shn->getbufp += 4;
shn->nbyteget -= 4;
return 1;
} /* word_get */
static int uvar_get(int nbin, shn_t *shn, SDL_RWops *rw, Sint32 *word)
{
Sint32 result;
if (shn->nbitget == 0)
{
BAIL_IF_MACRO(!word_get(shn, rw, &shn->gbuffer), NULL, 0);
shn->nbitget = 32;
} /* if */
for (result = 0; !(shn->gbuffer & (1L << --shn->nbitget)); result++)
{
if (shn->nbitget == 0)
{
BAIL_IF_MACRO(!word_get(shn, rw, &shn->gbuffer), NULL, 0);
shn->nbitget = 32;
} /* if */
} /* for */
while (nbin != 0)
{
if (shn->nbitget >= nbin)
{
result = ( (result << nbin) |
((shn->gbuffer >> (shn->nbitget - nbin)) &
mask_table[nbin]) );
shn->nbitget -= nbin;
break;
} /* if */
else
{
result = (result << shn->nbitget) |
(shn->gbuffer & mask_table[shn->nbitget]);
BAIL_IF_MACRO(!word_get(shn, rw, &shn->gbuffer), NULL, 0);
nbin -= shn->nbitget;
shn->nbitget = 32;
} /* else */
} /* while */
if (word != NULL)
*word = result;
return 1;
} /* uvar_get */
static int var_get(int nbin, shn_t *shn, SDL_RWops *rw, Sint32 *word)
{
BAIL_IF_MACRO(!uvar_get(nbin + 1, shn, rw, word), NULL, 0);
if ((*word) & 1)
*word = (Sint32) ~((*word) >> 1);
else
*word = (Sint32) ((*word) >> 1);
return 1;
} /* var_get */
static int ulong_get(shn_t *shn, SDL_RWops *rw, Sint32 *word)
{
Sint32 nbit;
Sint32 retval;
BAIL_IF_MACRO(!uvar_get(SHN_ULONGSIZE, shn, rw, &nbit), NULL, 0);
BAIL_IF_MACRO(!uvar_get(nbit, shn, rw, &retval), NULL, 0);
if (word != NULL)
*word = retval;
return 1;
} /* ulong_get */
static SDL_INLINE int uint_get(int nbit, shn_t *shn, SDL_RWops *rw, Sint32 *w)
{
return (shn->version == 0) ? uvar_get(nbit, shn, rw, w) : ulong_get(shn, rw, w);
} /* uint_get */
static int SHN_init(void)
{
return 1; /* initialization always successful. */
} /* SHN_init */
static void SHN_quit(void)
{
/* it's a no-op. */
} /* SHN_quit */
/*
* Look through the whole file for a SHN magic number. This is costly, so
* it should only be done if the user SWEARS they have a Shorten stream...
*/
static SDL_INLINE int extended_shn_magic_search(Sound_Sample *sample)
{
SDL_RWops *rw = ((Sound_SampleInternal *) sample->opaque)->rw;
Uint32 word = 0;
Uint8 ch;
while (1)
{
BAIL_IF_MACRO(SDL_RWread(rw, &ch, sizeof (ch), 1) != 1, NULL, -1);
word = ((word << 8) & 0xFFFFFF00) | ch;
if (SDL_SwapBE32(word) == SHN_MAGIC)
{
BAIL_IF_MACRO(SDL_RWread(rw, &ch, sizeof (ch), 1) != 1, NULL, -1);
return (int) ch;
} /* if */
} /* while */
return (int) ch;
} /* extended_shn_magic_search */
/* look for the magic number in the RWops and see what kind of file this is. */
static SDL_INLINE int determine_shn_version(Sound_Sample *sample,
const char *ext)
{
SDL_RWops *rw = ((Sound_SampleInternal *) sample->opaque)->rw;
Uint32 magic;
Uint8 ch;
/*
* Apparently the magic number can start at any byte offset in the file,
* and we should just discard prior data, but I'm going to restrict it
* to offset zero for now, so we don't chug down every file that might
* happen to pass through here. If the extension is explicitly "SHN", we
* check the whole stream, though.
*/
if (SDL_strcasecmp(ext, "shn") == 0)
return extended_shn_magic_search(sample);
BAIL_IF_MACRO(SDL_RWread(rw, &magic, sizeof (magic), 1) != 1, NULL, -1);
BAIL_IF_MACRO(SDL_SwapLE32(magic) != SHN_MAGIC, "SHN: Not a SHN file", -1);
BAIL_IF_MACRO(SDL_RWread(rw, &ch, sizeof (ch), 1) != 1, NULL, -1);
BAIL_IF_MACRO(ch > 3, "SHN: Unsupported file version", -1);
return (int) ch;
} /* determine_shn_version */
static void init_shn_offset(Sint32 **offset, int nchan, int nblock, int ftype)
{
Sint32 mean = 0;
int chan;
switch (ftype)
{
case SHN_TYPE_AU1:
case SHN_TYPE_S8:
case SHN_TYPE_S16HL:
case SHN_TYPE_S16LH:
case SHN_TYPE_ULAW:
case SHN_TYPE_AU2:
case SHN_TYPE_AU3:
case SHN_TYPE_ALAW:
mean = 0;
break;
case SHN_TYPE_U8:
mean = 0x80;
break;
case SHN_TYPE_U16HL:
case SHN_TYPE_U16LH:
mean = 0x8000;
break;
default:
__Sound_SetError("SHN: unknown file type");
return;
} /* switch */
for(chan = 0; chan < nchan; chan++)
{
int i;
for(i = 0; i < nblock; i++)
offset[chan][i] = mean;
} /* for */
} /* init_shn_offset */
static SDL_INLINE Uint16 cvt_shnftype_to_sdlfmt(Sint16 shntype)
{
switch (shntype)
{
case SHN_TYPE_S8:
return AUDIO_S8;
case SHN_TYPE_ALAW:
case SHN_TYPE_ULAW:
case SHN_TYPE_AU1:
case SHN_TYPE_AU2:
case SHN_TYPE_AU3:
case SHN_TYPE_U8:
return AUDIO_U8;
case SHN_TYPE_S16HL:
return AUDIO_S16MSB;
case SHN_TYPE_S16LH:
return AUDIO_S16LSB;
case SHN_TYPE_U16HL:
return AUDIO_U16MSB;
case SHN_TYPE_U16LH:
return AUDIO_U16LSB;
} /* switch */
return 0;
} /* cvt_shnftype_to_sdlfmt */
static SDL_INLINE int skip_bits(shn_t *shn, SDL_RWops *rw)
{
int i;
Sint32 skip;
Sint32 trash;
BAIL_IF_MACRO(!uint_get(SHN_NSKIPSIZE, shn, rw, &skip), NULL, 0);
for(i = 0; i < skip; i++)
{
BAIL_IF_MACRO(!uint_get(SHN_XBYTESIZE, shn, rw, &trash), NULL, 0);
} /* for */
return 1;
} /* skip_bits */
static Sint32 **shn_long2d(Uint32 n0, Uint32 n1)
{
Sint32 **array0;
Uint32 size = (n0 * sizeof (Sint32 *)) + (n0 * n1 * sizeof (Sint32));
array0 = (Sint32 **) SDL_malloc(size);
if (array0 != NULL)
{
int i;
Sint32 *array1 = (Sint32 *) (array0 + n0);
for(i = 0; i < n0; i++)
array0[i] = array1 + (i * n1);
} /* if */
return array0;
} /* shn_long2d */
#define riffID 0x46464952 /* "RIFF", in ascii. */
#define waveID 0x45564157 /* "WAVE", in ascii. */
#define fmtID 0x20746D66 /* "fmt ", in ascii. */
#define dataID 0x61746164 /* "data", in ascii. */
static int verb_ReadLE32(shn_t *shn, SDL_RWops *rw, Uint32 *word)
{
int i;
Uint8 chars[4];
Sint32 byte;
for (i = 0; i < 4; i++)
{
if (!uvar_get(SHN_VERBATIM_BYTE_SIZE, shn, rw, &byte))
return 0;
chars[i] = (Uint8) byte;
} /* for */
SDL_memcpy(word, chars, sizeof (*word));
*word = SDL_SwapLE32(*word);
return 1;
} /* verb_ReadLE32 */
static int verb_ReadLE16(shn_t *shn, SDL_RWops *rw, Uint16 *word)
{
int i;
Uint8 chars[2];
Sint32 byte;
for (i = 0; i < 2; i++)
{
if (!uvar_get(SHN_VERBATIM_BYTE_SIZE, shn, rw, &byte))
return 0;
chars[i] = (Uint8) byte;
} /* for */
SDL_memcpy(word, chars, sizeof (*word));
*word = SDL_SwapLE16(*word);
return 1;
} /* verb_ReadLE16 */
static SDL_INLINE int parse_riff_header(shn_t *shn, Sound_Sample *sample)
{
Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
SDL_RWops *rw = internal->rw;
Uint16 u16;
Uint32 u32;
Sint32 cklen;
Uint32 bytes_per_second;
BAIL_IF_MACRO(!uvar_get(SHN_VERBATIM_CKSIZE_SIZE, shn, rw, &cklen), NULL, 0);
BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* RIFF header */
BAIL_IF_MACRO(u32 != riffID, "SHN: No RIFF header.", 0);
BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* length */
BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* WAVE header */
BAIL_IF_MACRO(u32 != waveID, "SHN: No WAVE header.", 0);
BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* 'fmt ' header */
BAIL_IF_MACRO(u32 != fmtID, "SHN: No 'fmt ' header.", 0);
BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* chunksize */
BAIL_IF_MACRO(!verb_ReadLE16(shn, rw, &u16), NULL, 0); /* format */
BAIL_IF_MACRO(!verb_ReadLE16(shn, rw, &u16), NULL, 0); /* channels */
sample->actual.channels = u16;
BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* sample rate */
sample->actual.rate = u32;
BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* bytespersec */
bytes_per_second = u32;
BAIL_IF_MACRO(!verb_ReadLE16(shn, rw, &u16), NULL, 0); /* blockalign */
BAIL_IF_MACRO(!verb_ReadLE16(shn, rw, &u16), NULL, 0); /* bitspersample */
BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* 'data' header */
BAIL_IF_MACRO(u32 != dataID, "SHN: No 'data' header.", 0);
BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* chunksize */
internal->total_time = u32 / bytes_per_second * 1000;
internal->total_time += (u32 % bytes_per_second) * 1000 / bytes_per_second;
return 1;
} /* parse_riff_header */
static int SHN_open(Sound_Sample *sample, const char *ext)
{
Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
SDL_RWops *rw = internal->rw;
shn_t _shn;
shn_t *shn = &_shn; /* malloc and copy later. */
Sint32 cmd;
Sint32 chan;
SDL_memset(shn, '\0', sizeof (shn_t));
shn->getbufp = shn->getbuf = (Uint8 *) SDL_malloc(SHN_BUFSIZ);
shn->datatype = SHN_TYPE_EOF;
shn->nchan = DEFAULT_NCHAN;
shn->blocksize = DEFAULT_BLOCK_SIZE;
shn->maxnlpc = DEFAULT_MAXNLPC;
shn->nmean = UNDEFINED_UINT;
shn->version = determine_shn_version(sample, ext);
if (shn->version == -1) goto shn_open_puke;
if (!uint_get(SHN_TYPESIZE, shn, rw, &shn->datatype)) goto shn_open_puke;
if (!uint_get(SHN_CHANNELSIZE, shn, rw, &shn->nchan)) goto shn_open_puke;
sample->actual.format = cvt_shnftype_to_sdlfmt(shn->datatype);
if (sample->actual.format == 0)
{
SDL_SetError(ERR_UNSUPPORTED_FORMAT);
goto shn_open_puke;
} /* if */
if (shn->version > 0)
{
int rc = uint_get((int) (SDL_log((double) DEFAULT_BLOCK_SIZE) / M_LN2),
shn, rw, &shn->blocksize);
if (!rc) goto shn_open_puke;;
if (!uint_get(SHN_LPCQSIZE, shn, rw, &shn->maxnlpc)) goto shn_open_puke;
if (!uint_get(0, shn, rw, &shn->nmean)) goto shn_open_puke;
if (!skip_bits(shn, rw)) goto shn_open_puke;
} /* else */
shn->nwrap = (shn->maxnlpc > 3) ? shn->maxnlpc : 3;
/* grab some space for the input buffer */
shn->buffer = shn_long2d((Uint32) shn->nchan, shn->blocksize + shn->nwrap);
shn->offset = shn_long2d((Uint32) shn->nchan, MAX_MACRO(1, shn->nmean));
for (chan = 0; chan < shn->nchan; chan++)
{
int i;
for(i = 0; i < shn->nwrap; i++)
shn->buffer[chan][i] = 0;
shn->buffer[chan] += shn->nwrap;
} /* for */
if (shn->maxnlpc > 0)
{
shn->qlpc = (int *) SDL_malloc((Uint32) (shn->maxnlpc * sizeof (Sint32)));
if (shn->qlpc == NULL)
{
__Sound_SetError(ERR_OUT_OF_MEMORY);
goto shn_open_puke;
} /* if */
} /* if */
if (shn->version > 1)
shn->lpcqoffset = SHN_LPCQOFFSET_VER2;
init_shn_offset(shn->offset, shn->nchan,
MAX_MACRO(1, shn->nmean), shn->datatype);
if ( (!uvar_get(SHN_FNSIZE, shn, rw, &cmd)) ||
(cmd != SHN_FN_VERBATIM) ||
(!parse_riff_header(shn, sample)) )
{
if (cmd != SHN_FN_VERBATIM) /* the other conditions set error state */
__Sound_SetError("SHN: Expected VERBATIM function");
goto shn_open_puke;
return 0;
} /* if */
shn->start_pos = SDL_RWtell(rw);
shn = (shn_t *) SDL_malloc(sizeof (shn_t));
if (shn == NULL)
{
__Sound_SetError(ERR_OUT_OF_MEMORY);
goto shn_open_puke;
} /* if */
SDL_memcpy(shn, &_shn, sizeof (shn_t));
internal->decoder_private = shn;
SNDDBG(("SHN: Accepting data stream.\n"));
sample->flags = SOUND_SAMPLEFLAG_NONE;
return 1; /* we'll handle this data. */
shn_open_puke:
if (_shn.getbuf)
SDL_free(_shn.getbuf);
if (_shn.buffer != NULL)
SDL_free(_shn.buffer);
if (_shn.offset != NULL)
SDL_free(_shn.offset);
if (_shn.qlpc != NULL)
SDL_free(_shn.qlpc);
return 0;
} /* SHN_open */
static void fix_bitshift(Sint32 *buffer, int nitem, int bitshift, int ftype)
{
int i;
if (ftype == SHN_TYPE_AU1)
{
for (i = 0; i < nitem; i++)
buffer[i] = ulaw_outward[bitshift][buffer[i] + 128];
} /* if */
else if (ftype == SHN_TYPE_AU2)
{
for(i = 0; i < nitem; i++)
{
if (buffer[i] >= 0)
buffer[i] = ulaw_outward[bitshift][buffer[i] + 128];
else if (buffer[i] == -1)
buffer[i] = NEGATIVE_ULAW_ZERO;
else
buffer[i] = ulaw_outward[bitshift][buffer[i] + 129];
} /* for */
} /* else if */
else
{
if (bitshift != 0)
{
for(i = 0; i < nitem; i++)
buffer[i] <<= bitshift;
} /* if */
} /* else */
} /* fix_bitshift */
static void SHN_close(Sound_Sample *sample)
{
Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
shn_t *shn = (shn_t *) internal->decoder_private;
if (shn->qlpc != NULL)
SDL_free(shn->qlpc);
if (shn->backBuffer != NULL)
SDL_free(shn->backBuffer);
if (shn->offset != NULL)
SDL_free(shn->offset);
if (shn->buffer != NULL)
SDL_free(shn->buffer);
if (shn->getbuf != NULL)
SDL_free(shn->getbuf);
SDL_free(shn);
} /* SHN_close */
/* xLaw conversions... */
/* adapted by ajr for int input */
static Uint8 Slinear2ulaw(int sample)
{
/*
** This routine converts from linear to ulaw.
**
** Craig Reese: IDA/Supercomputing Research Center
** Joe Campbell: Department of Defense
** 29 September 1989
**
** References:
** 1) CCITT Recommendation G.711 (very difficult to follow)
** 2) "A New Digital Technique for Implementation of Any
** Continuous PCM Companding Law," Villeret, Michel,
** et al. 1973 IEEE Int. Conf. on Communications, Vol 1,
** 1973, pg. 11.12-11.17
** 3) MIL-STD-188-113,"Interoperability and Performance Standards
** for Analog-to_Digital Conversion Techniques,"
** 17 February 1987
**
** Input: Signed 16 bit linear sample
** Output: 8 bit ulaw sample
*/
#define BIAS 0x84 /* define the add-in bias for 16 bit samples */
#define CLIP 32635
int sign, exponent, mantissa;
Uint8 ulawbyte;
static const int exp_lut[256] = {0,0,1,1,2,2,2,2,3,3,3,3,3,3,3,3,
4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7};
/* Get the sample into sign-magnitude. */
if (sample >= 0)
sign = 0;
else
{
sign = 0x80;
sample = -sample;
} /* else */
/* clip the magnitude */
if (sample > CLIP)
sample = CLIP;
/* Convert from 16 bit linear to ulaw. */
sample = sample + BIAS;
exponent = exp_lut[( sample >> 7 ) & 0xFF];
mantissa = (sample >> (exponent + 3)) & 0x0F;
ulawbyte = ~(sign | (exponent << 4) | mantissa);
return ulawbyte;
} /* Slinear2ulaw */
/* this is derived from the Sun code - it is a bit simpler and has int input */
#define QUANT_MASK (0xf) /* Quantization field mask. */
#define NSEGS (8) /* Number of A-law segments. */
#define SEG_SHIFT (4) /* Left shift for segment number. */
static Uint8 Slinear2alaw(Sint32 linear)
{
int seg;
Uint8 aval, mask;
static const Sint32 seg_aend[NSEGS] =
{
0x1f,0x3f,0x7f,0xff,0x1ff,0x3ff,0x7ff,0xfff
};
linear >>= 3;
if(linear >= 0)
mask = 0xd5; /* sign (7th) bit = 1 */
else
{
mask = 0x55; /* sign bit = 0 */
linear = -linear - 1;
} /* else */
/* Convert the scaled magnitude to segment number. */
for (seg = 0; (seg < NSEGS) && (linear > seg_aend[seg]); seg++);
/* Combine the sign, segment, and quantization bits. */
if (seg >= NSEGS) /* out of range, return maximum value. */
return (Uint8) (0x7F ^ mask);
aval = (Uint8) seg << SEG_SHIFT;
if (seg < 2)
aval |= (linear >> 1) & QUANT_MASK;
else
aval |= (linear >> seg) & QUANT_MASK;
return (aval ^ mask);
} /* Slinear2alaw */
/* convert from signed ints to a given type and write */
static Uint32 put_to_buffers(Sound_Sample *sample, Uint32 bw)
{
Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
shn_t *shn = (shn_t *) internal->decoder_private;
int i, chan;
Sint32 *data0 = shn->buffer[0];
Sint32 nitem = shn->blocksize;
int datasize = ((sample->actual.format & 0xFF) / 8);
Uint32 bsiz = shn->nchan * nitem * datasize;
SDL_assert(shn->backBufLeft == 0);
if (shn->backBufferSize < bsiz)
{
void *rc = SDL_realloc(shn->backBuffer, bsiz);
if (rc == NULL)
{
sample->flags |= SOUND_SAMPLEFLAG_ERROR;
BAIL_MACRO(ERR_OUT_OF_MEMORY, 0);
} /* if */
shn->backBuffer = (Uint8 *) rc;
shn->backBufferSize = bsiz;
} /* if */
switch (shn->datatype)
{
case SHN_TYPE_AU1: /* leave the conversion to fix_bitshift() */
case SHN_TYPE_AU2:
{
Uint8 *writebufp = shn->backBuffer;
if (shn->nchan == 1)
{
for (i = 0; i < nitem; i++)
*writebufp++ = data0[i];
} /* if */
else
{
for (i = 0; i < nitem; i++)
{
for (chan = 0; chan < shn->nchan; chan++)
*writebufp++ = shn->buffer[chan][i];
} /* for */
} /* else */
} /* case */
break;
case SHN_TYPE_U8:
{
Uint8 *writebufp = shn->backBuffer;
if (shn->nchan == 1)
{
for (i = 0; i < nitem; i++)
*writebufp++ = CAPMAXUCHAR(data0[i]);
} /* if */
else
{
for (i = 0; i < nitem; i++)
{
for (chan = 0; chan < shn->nchan; chan++)
*writebufp++ = CAPMAXUCHAR(shn->buffer[chan][i]);
} /* for */
} /* else */
} /* case */
break;
case SHN_TYPE_S8:
{
Sint8 *writebufp = (Sint8 *) shn->backBuffer;
if (shn->nchan == 1)
{
for(i = 0; i < nitem; i++)
*writebufp++ = CAPMAXSCHAR(data0[i]);
} /* if */
else
{
for(i = 0; i < nitem; i++)
{
for(chan = 0; chan < shn->nchan; chan++)
*writebufp++ = CAPMAXSCHAR(shn->buffer[chan][i]);
} /* for */
} /* else */
} /* case */
break;
case SHN_TYPE_S16HL:
case SHN_TYPE_S16LH:
{
Sint16 *writebufp = (Sint16 *) shn->backBuffer;
if (shn->nchan == 1)
{
for (i = 0; i < nitem; i++)
*writebufp++ = CAPMAXSHORT(data0[i]);
} /* if */
else
{
for (i = 0; i < nitem; i++)
{
for (chan = 0; chan < shn->nchan; chan++)
*writebufp++ = CAPMAXSHORT(shn->buffer[chan][i]);
} /* for */
} /* else */
} /* case */
break;
case SHN_TYPE_U16HL:
case SHN_TYPE_U16LH:
{
Uint16 *writebufp = (Uint16 *) shn->backBuffer;
if (shn->nchan == 1)
{
for (i = 0; i < nitem; i++)
*writebufp++ = CAPMAXUSHORT(data0[i]);
} /* if */
else
{
for (i = 0; i < nitem; i++)
{
for (chan = 0; chan < shn->nchan; chan++)
*writebufp++ = CAPMAXUSHORT(shn->buffer[chan][i]);
} /* for */
} /* else */
} /* case */
break;
case SHN_TYPE_ULAW:
{
Uint8 *writebufp = shn->backBuffer;
if (shn->nchan == 1)
{
for(i = 0; i < nitem; i++)
*writebufp++ = Slinear2ulaw(CAPMAXSHORT((data0[i] << 3)));
} /* if */
else
{
for(i = 0; i < nitem; i++)
{
for(chan = 0; chan < shn->nchan; chan++)
*writebufp++ = Slinear2ulaw(CAPMAXSHORT((shn->buffer[chan][i] << 3)));
} /* for */
} /* else */
} /* case */
break;
case SHN_TYPE_AU3:
{
Uint8 *writebufp = shn->backBuffer;
if (shn->nchan == 1)
{
for (i = 0; i < nitem; i++)
if(data0[i] < 0)
*writebufp++ = (127 - data0[i]) ^ 0xd5;
else
*writebufp++ = (data0[i] + 128) ^ 0x55;
} /* if */
else
{
for (i = 0; i < nitem; i++)
{
for (chan = 0; chan < shn->nchan; chan++)
{
if (shn->buffer[chan][i] < 0)
*writebufp++ = (127 - shn->buffer[chan][i]) ^ 0xd5;
else
*writebufp++ = (shn->buffer[chan][i] + 128) ^ 0x55;
} /* for */
} /* for */
} /* else */
} /* case */
break;
case SHN_TYPE_ALAW:
{
Uint8 *writebufp = shn->backBuffer;
if (shn->nchan == 1)
{
for (i = 0; i < nitem; i++)
*writebufp++ = Slinear2alaw(CAPMAXSHORT((data0[i] << 3)));
} /* if */
else
{
for (i = 0; i < nitem; i++)
{
for(chan = 0; chan < shn->nchan; chan++)
*writebufp++ = Slinear2alaw(CAPMAXSHORT((shn->buffer[chan][i] << 3)));
} /* for */
}/* else */
} /* case */
break;
} /* switch */
i = MIN_MACRO(internal->buffer_size - bw, bsiz);
SDL_memcpy((char *)internal->buffer + bw, shn->backBuffer, i);
shn->backBufLeft = bsiz - i;
SDL_memcpy(shn->backBuffer, shn->backBuffer + i, shn->backBufLeft);
return i;
} /* put_to_buffers */
#define ROUNDEDSHIFTDOWN(x, n) (((n) == 0) ? (x) : ((x) >> ((n) - 1)) >> 1)
static Uint32 SHN_read(Sound_Sample *sample)
{
Uint32 retval = 0;
Sint32 chan = 0;
Uint32 cpyBytes = 0;
Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
SDL_RWops *rw = internal->rw;
shn_t *shn = (shn_t *) internal->decoder_private;
Sint32 cmd;
SDL_assert(shn->backBufLeft >= 0);
/* see if there are leftovers to copy... */
if (shn->backBufLeft > 0)
{
retval = MIN_MACRO(shn->backBufLeft, internal->buffer_size);
SDL_memcpy(internal->buffer, shn->backBuffer, retval);
shn->backBufLeft -= retval;
SDL_memcpy(shn->backBuffer, shn->backBuffer + retval, shn->backBufLeft);
} /* if */
SDL_assert((shn->backBufLeft == 0) || (retval == internal->buffer_size));
/* get commands from file and execute them */
while (retval < internal->buffer_size)
{
if (!uvar_get(SHN_FNSIZE, shn, rw, &cmd))
{
sample->flags |= SOUND_SAMPLEFLAG_ERROR;
return retval;
} /* if */
if (cmd == SHN_FN_QUIT)
{
sample->flags |= SOUND_SAMPLEFLAG_EOF;
return retval;
} /* if */
switch(cmd)
{
case SHN_FN_ZERO:
case SHN_FN_DIFF0:
case SHN_FN_DIFF1:
case SHN_FN_DIFF2:
case SHN_FN_DIFF3:
case SHN_FN_QLPC:
{
Sint32 i;
Sint32 coffset, *cbuffer = shn->buffer[chan];
Sint32 resn = 0, nlpc, j;
if (cmd != SHN_FN_ZERO)
{
if (!uvar_get(SHN_ENERGYSIZE, shn, rw, &resn))
{
sample->flags |= SOUND_SAMPLEFLAG_ERROR;
return retval;
} /* if */
/* version 0 differed in definition of var_get */
if (shn->version == 0)
resn--;
} /* if */
/* find mean offset : N.B. this code duplicated */
if (shn->nmean == 0)
coffset = shn->offset[chan][0];
else
{
Sint32 sum = (shn->version < 2) ? 0 : shn->nmean / 2;
for (i = 0; i < shn->nmean; i++)
sum += shn->offset[chan][i];
if (shn->version < 2)
coffset = sum / shn->nmean;
else
coffset = ROUNDEDSHIFTDOWN(sum / shn->nmean, shn->bitshift);
} /* else */
switch (cmd)
{
case SHN_FN_ZERO:
for (i = 0; i < shn->blocksize; i++)
cbuffer[i] = 0;
break;
case SHN_FN_DIFF0:
for(i = 0; i < shn->blocksize; i++)
{
if (!var_get(resn, shn, rw, &cbuffer[i]))
{
sample->flags |= SOUND_SAMPLEFLAG_ERROR;
return retval;
} /* if */
cbuffer[i] += coffset;
} /* for */
break;
case SHN_FN_DIFF1:
for(i = 0; i < shn->blocksize; i++)
{
if (!var_get(resn, shn, rw, &cbuffer[i]))
{
sample->flags |= SOUND_SAMPLEFLAG_ERROR;
return retval;
} /* if */
cbuffer[i] += cbuffer[i - 1];
} /* for */
break;
case SHN_FN_DIFF2:
for (i = 0; i < shn->blocksize; i++)
{
if (!var_get(resn, shn, rw, &cbuffer[i]))
{
sample->flags |= SOUND_SAMPLEFLAG_ERROR;
return retval;
} /* if */
cbuffer[i] += (2 * cbuffer[i-1] - cbuffer[i-2]);
} /* for */
break;
case SHN_FN_DIFF3:
for (i = 0; i < shn->blocksize; i++)
{
if (!var_get(resn, shn, rw, &cbuffer[i]))
{
sample->flags |= SOUND_SAMPLEFLAG_ERROR;
return retval;
} /* if */
cbuffer[i] += 3 * (cbuffer[i - 1] - cbuffer[i - 2]) + cbuffer[i - 3];
} /* for */
break;
case SHN_FN_QLPC:
if (!uvar_get(SHN_LPCQSIZE, shn, rw, &nlpc))
{
sample->flags |= SOUND_SAMPLEFLAG_ERROR;
return retval;
} /* if */
for(i = 0; i < nlpc; i++)
{
if (!var_get(SHN_LPCQUANT, shn, rw, &shn->qlpc[i]))
{
sample->flags |= SOUND_SAMPLEFLAG_ERROR;
return retval;
} /* if */
} /* for */
for(i = 0; i < nlpc; i++)
cbuffer[i - nlpc] -= coffset;
for(i = 0; i < shn->blocksize; i++)
{
Sint32 sum = shn->lpcqoffset;
for(j = 0; j < nlpc; j++)
sum += shn->qlpc[j] * cbuffer[i - j - 1];
if (!var_get(resn, shn, rw, &cbuffer[i]))
{
sample->flags |= SOUND_SAMPLEFLAG_ERROR;
return retval;
} /* if */
cbuffer[i] += (sum >> SHN_LPCQUANT);
} /* for */
if (coffset != 0)
{
for(i = 0; i < shn->blocksize; i++)
cbuffer[i] += coffset;
} /* if */
break;
} /* switch */
/* store mean value if appropriate : N.B. Duplicated code */
if (shn->nmean > 0)
{
Sint32 sum = (shn->version < 2) ? 0 : shn->blocksize / 2;
for (i = 0; i < shn->blocksize; i++)
sum += cbuffer[i];
for(i = 1; i < shn->nmean; i++)
shn->offset[chan][i - 1] = shn->offset[chan][i];
if (shn->version < 2)
shn->offset[chan][shn->nmean - 1] = sum / shn->blocksize;
else
shn->offset[chan][shn->nmean - 1] = (sum / shn->blocksize) << shn->bitshift;
} /* if */
/* do the wrap */
for(i = -shn->nwrap; i < 0; i++)
cbuffer[i] = cbuffer[i + shn->blocksize];
fix_bitshift(cbuffer, shn->blocksize, shn->bitshift, shn->datatype);
if (chan == shn->nchan - 1)
{
retval += put_to_buffers(sample, retval);
if (sample->flags & SOUND_SAMPLEFLAG_ERROR)
return retval;
} /* if */
chan = (chan + 1) % shn->nchan;
break;
} /* case */
case SHN_FN_BLOCKSIZE:
if (!uint_get((int) (SDL_log((double) shn->blocksize) / M_LN2),
shn, rw, &shn->blocksize))
{
sample->flags |= SOUND_SAMPLEFLAG_ERROR;
return retval;
} /* if */
break;
case SHN_FN_BITSHIFT:
if (!uvar_get(SHN_BITSHIFTSIZE, shn, rw, &shn->bitshift))
{
sample->flags |= SOUND_SAMPLEFLAG_ERROR;
return retval;
} /* if */
break;
case SHN_FN_VERBATIM:
default:
sample->flags |= SOUND_SAMPLEFLAG_ERROR;
BAIL_MACRO("SHN: Unhandled function.", retval);
} /* switch */
} /* while */
return retval;
} /* SHN_read */
static int SHN_rewind(Sound_Sample *sample)
{
Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
shn_t *shn = (shn_t *) internal->decoder_private;
#if 0
int rc = SDL_RWseek(internal->rw, shn->start_pos, SEEK_SET);
BAIL_IF_MACRO(rc != shn->start_pos, ERR_IO_ERROR, 0);
/* !!! FIXME: set state. */
return 1;
#else
/*
* !!! FIXME: This is really unacceptable; state should be reset and
* !!! FIXME: the RWops should be pointed to the start of the data
* !!! FIXME: to decode. The below kludge adds unneeded overhead and
* !!! FIXME: risk of failure.
*/
BAIL_IF_MACRO(SDL_RWseek(internal->rw, 0, SEEK_SET) != 0, ERR_IO_ERROR, 0);
SHN_close(sample);
return SHN_open(sample, "SHN");
#endif
} /* SHN_rewind */
static int SHN_seek(Sound_Sample *sample, Uint32 ms)
{
/*
* (This CAN be done for SHNs that have a seek table at the end of the
* stream, btw.)
*/
BAIL_MACRO("SHN: Seeking not implemented", 0);
} /* SHN_seek */
static const char *extensions_shn[] = { "SHN", NULL };
const Sound_DecoderFunctions __Sound_DecoderFunctions_SHN =
{
{
extensions_shn,
"Shorten-compressed audio data",
"Ryan C. Gordon <icculus@icculus.org>",
"https://icculus.org/SDL_sound/"
},
SHN_init, /* init() method */
SHN_quit, /* quit() method */
SHN_open, /* open() method */
SHN_close, /* close() method */
SHN_read, /* read() method */
SHN_rewind, /* rewind() method */
SHN_seek /* seek() method */
};
#endif /* defined SOUND_SUPPORTS_SHN */
/* end of SDL_sound_shn.c ... */