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authorFabrice Bellard <fabrice@bellard.org>2001-09-15 22:40:28 +0000
committerFabrice Bellard <fabrice@bellard.org>2001-09-15 22:40:28 +0000
commit239c2f4cd0a488617d2a49e0c317748dd3f8fddc (patch)
tree5dd6271aea217d0a5c955a68f82aa06b90079f6f
parentc8fbc22deea1a0498b212943ff4e1d0c08e384e2 (diff)
downloadffmpeg-239c2f4cd0a488617d2a49e0c317748dd3f8fddc.tar.gz
added completely new mpeg audio decoder (integer only, free format support, lsf/mpeg25 support, high/low precision support, simpler code)
Originally committed as revision 117 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat
-rw-r--r--libavcodec/mpegaudiodec.c2328
1 files changed, 2208 insertions, 120 deletions
diff --git a/libavcodec/mpegaudiodec.c b/libavcodec/mpegaudiodec.c
index f3fa90af55..ca610d65ef 100644
--- a/libavcodec/mpegaudiodec.c
+++ b/libavcodec/mpegaudiodec.c
@@ -16,76 +16,934 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
+//#define DEBUG
#include "avcodec.h"
-#include "mpglib/mpg123.h"
+#include <math.h>
+#include "mpegaudio.h"
/*
- * TODO:
- * - add free format
- * - do not rely anymore on mpglib (first step: implement dct64 and decoding filter)
+ * TODO:
+ * - in low precision mode, use more 16 bit multiplies in synth filter
+ * - test lsf / mpeg25 extensively.
*/
+/* define USE_HIGHPRECISION to have a bit exact (but slower) mpeg
+ audio decoder */
+//#define USE_HIGHPRECISION
+
+#ifdef USE_HIGHPRECISION
+#define FRAC_BITS 23 /* fractional bits for sb_samples and dct */
+#define WFRAC_BITS 16 /* fractional bits for window */
+#else
+#define FRAC_BITS 15 /* fractional bits for sb_samples and dct */
+#define WFRAC_BITS 14 /* fractional bits for window */
+#endif
+
+#define FRAC_ONE (1 << FRAC_BITS)
+
+#define MULL(a,b) (((INT64)(a) * (INT64)(b)) >> FRAC_BITS)
+#define MUL64(a,b) ((INT64)(a) * (INT64)(b))
+#define FIX(a) ((int)((a) * FRAC_ONE))
+/* WARNING: only correct for posititive numbers */
+#define FIXR(a) ((int)((a) * FRAC_ONE + 0.5))
+#define FRAC_RND(a) (((a) + (FRAC_ONE/2)) >> FRAC_BITS)
+
+#if FRAC_BITS <= 15
+typedef INT16 MPA_INT;
+#else
+typedef INT32 MPA_INT;
+#endif
+
+/****************/
+
#define HEADER_SIZE 4
#define BACKSTEP_SIZE 512
typedef struct MPADecodeContext {
- struct mpstr mpstr;
- UINT8 inbuf1[2][MAXFRAMESIZE + BACKSTEP_SIZE]; /* input buffer */
+ UINT8 inbuf1[2][MPA_MAX_CODED_FRAME_SIZE + BACKSTEP_SIZE]; /* input buffer */
int inbuf_index;
UINT8 *inbuf_ptr, *inbuf;
int frame_size;
+ int free_format_frame_size; /* frame size in case of free format
+ (zero if currently unknown) */
+ /* next header (used in free format parsing) */
+ UINT32 free_format_next_header;
int error_protection;
int layer;
int sample_rate;
+ int sample_rate_index; /* between 0 and 8 */
int bit_rate;
int old_frame_size;
GetBitContext gb;
+ int nb_channels;
+ int mode;
+ int mode_ext;
+ int lsf;
+ MPA_INT synth_buf[MPA_MAX_CHANNELS][512 * 2];
+ int synth_buf_offset[MPA_MAX_CHANNELS];
+ INT32 sb_samples[MPA_MAX_CHANNELS][36][SBLIMIT];
+ INT32 mdct_buf[MPA_MAX_CHANNELS][SBLIMIT * 18]; /* previous samples, for layer 3 MDCT */
+#ifdef DEBUG
+ int frame_count;
+#endif
} MPADecodeContext;
-/* XXX: suppress that mess */
-struct mpstr *gmp;
-GetBitContext *gmp_gb;
-static MPADecodeContext *gmp_s;
+/* layer 3 "granule" */
+typedef struct GranuleDef {
+ UINT8 scfsi;
+ int part2_3_length;
+ int big_values;
+ int global_gain;
+ int scalefac_compress;
+ UINT8 block_type;
+ UINT8 switch_point;
+ int table_select[3];
+ int subblock_gain[3];
+ UINT8 scalefac_scale;
+ UINT8 count1table_select;
+ int region_size[3]; /* number of huffman codes in each region */
+ int preflag;
+ int short_start, long_end; /* long/short band indexes */
+ UINT8 scale_factors[40];
+ INT32 sb_hybrid[SBLIMIT * 18]; /* 576 samples */
+} GranuleDef;
-/* XXX: merge constants with encoder */
-static const unsigned short mp_bitrate_tab[2][3][15] = {
- { {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}
- }
+#define MODE_EXT_MS_STEREO 2
+#define MODE_EXT_I_STEREO 1
+
+/* layer 3 huffman tables */
+typedef struct HuffTable {
+ int xsize;
+ const UINT8 *bits;
+ const UINT16 *codes;
+} HuffTable;
+
+#include "mpegaudiodectab.h"
+
+/* vlc structure for decoding layer 3 huffman tables */
+static VLC huff_vlc[16];
+static UINT8 *huff_code_table[16];
+static VLC huff_quad_vlc[2];
+/* computed from band_size_long */
+static UINT16 band_index_long[9][23];
+/* XXX: free when all decoders are closed */
+#define TABLE_4_3_SIZE (8191 + 16)
+static UINT8 *table_4_3_exp;
+#if FRAC_BITS <= 15
+static UINT16 *table_4_3_value;
+#else
+static UINT32 *table_4_3_value;
+#endif
+/* intensity stereo coef table */
+static INT32 is_table[2][16];
+static INT32 is_table_lsf[2][2][16];
+static INT32 csa_table[8][2];
+static INT32 mdct_win[8][36];
+
+/* lower 2 bits: modulo 3, higher bits: shift */
+static UINT16 scale_factor_modshift[64];
+/* [i][j]: 2^(-j/3) * FRAC_ONE * 2^(i+2) / (2^(i+2) - 1) */
+static INT32 scale_factor_mult[15][3];
+/* mult table for layer 2 group quantization */
+
+#define SCALE_GEN(v) \
+{ FIXR(1.0 * (v)), FIXR(0.7937005259 * (v)), FIXR(0.6299605249 * (v)) }
+
+static INT32 scale_factor_mult2[3][3] = {
+ SCALE_GEN(1.0 / 3.0), /* 3 steps */
+ SCALE_GEN(1.0 / 5.0), /* 5 steps */
+ SCALE_GEN(1.0 / 9.0), /* 9 steps */
+};
+
+/* 2^(n/4) */
+static UINT32 scale_factor_mult3[4] = {
+ FIXR(1.0),
+ FIXR(1.18920711500272106671),
+ FIXR(1.41421356237309504880),
+ FIXR(1.68179283050742908605),
};
-static unsigned short mp_freq_tab[3] = { 44100, 48000, 32000 };
+static MPA_INT window[512];
+
+/* layer 1 unscaling */
+/* n = number of bits of the mantissa minus 1 */
+static inline int l1_unscale(int n, int mant, int scale_factor)
+{
+ int shift, mod;
+ INT64 val;
+
+ shift = scale_factor_modshift[scale_factor];
+ mod = shift & 3;
+ shift >>= 2;
+ val = MUL64(mant + (-1 << n) + 1, scale_factor_mult[n-1][mod]);
+ shift += n;
+ return (int)((val + (1 << (shift - 1))) >> shift);
+}
+
+static inline int l2_unscale_group(int steps, int mant, int scale_factor)
+{
+ int shift, mod, val;
+
+ shift = scale_factor_modshift[scale_factor];
+ mod = shift & 3;
+ shift >>= 2;
+ /* XXX: store the result directly */
+ val = (2 * (mant - (steps >> 1))) * scale_factor_mult2[steps >> 2][mod];
+ return (val + (1 << (shift - 1))) >> shift;
+}
+
+/* compute value^(4/3) * 2^(exponent/4). It normalized to FRAC_BITS */
+static inline int l3_unscale(int value, int exponent)
+{
+#if FRAC_BITS <= 15
+ unsigned int m;
+#else
+ UINT64 m;
+#endif
+ int e;
+
+ e = table_4_3_exp[value];
+ e += (exponent >> 2);
+ e = FRAC_BITS - e;
+#if FRAC_BITS <= 15
+ if (e > 31)
+ e = 31;
+#endif
+ m = table_4_3_value[value];
+#if FRAC_BITS <= 15
+ m = (m * scale_factor_mult3[exponent & 3]);
+ m = (m + (1 << (e-1))) >> e;
+ return m;
+#else
+ m = MUL64(m, scale_factor_mult3[exponent & 3]);
+ m = (m + (UINT64_C(1) << (e-1))) >> e;
+ return m;
+#endif
+}
+
static int decode_init(AVCodecContext * avctx)
{
MPADecodeContext *s = avctx->priv_data;
- struct mpstr *mp = &s->mpstr;
static int init;
-
- mp->fr.single = -1;
- mp->synth_bo = 1;
+ int i, j, k;
if(!init) {
+ /* scale factors table for layer 1/2 */
+ for(i=0;i<64;i++) {
+ int shift, mod;
+ /* 1.0 (i = 3) is normalized to 2 ^ FRAC_BITS */
+ shift = (i / 3) - 1;
+ mod = i % 3;
+#if FRAC_BITS <= 15
+ if (shift > 31)
+ shift = 31;
+#endif
+ scale_factor_modshift[i] = mod | (shift << 2);
+ }
+
+ /* scale factor multiply for layer 1 */
+ for(i=0;i<15;i++) {
+ int n, norm;
+ n = i + 2;
+ norm = ((INT64_C(1) << n) * FRAC_ONE) / ((1 << n) - 1);
+ scale_factor_mult[i][0] = MULL(FIXR(1.0), norm);
+ scale_factor_mult[i][1] = MULL(FIXR(0.7937005259), norm);
+ scale_factor_mult[i][2] = MULL(FIXR(0.6299605249), norm);
+ dprintf("%d: norm=%x s=%x %x %x\n",
+ i, norm,
+ scale_factor_mult[i][0],
+ scale_factor_mult[i][1],
+ scale_factor_mult[i][2]);
+ }
+
+ /* window */
+ /* max = 18760, max sum over all 16 coefs : 44736 */
+ for(i=0;i<257;i++) {
+ int v;
+ v = mpa_enwindow[i];
+#if WFRAC_BITS < 16
+ v = (v + (1 << (16 - WFRAC_BITS - 1))) >> (16 - WFRAC_BITS);
+#endif
+ window[i] = v;
+ if ((i & 63) != 0)
+ v = -v;
+ if (i != 0)
+ window[512 - i] = v;
+ }
+
+ /* huffman decode tables */
+ huff_code_table[0] = NULL;
+ for(i=1;i<16;i++) {
+ const HuffTable *h = &mpa_huff_tables[i];
+ int xsize, n, x, y;
+ UINT8 *code_table;
+
+ xsize = h->xsize;
+ n = xsize * xsize;
+ /* XXX: fail test */
+ init_vlc(&huff_vlc[i], 8, n,
+ h->bits, 1, 1, h->codes, 2, 2);
+
+ code_table = av_mallocz(n);
+ j = 0;
+ for(x=0;x<xsize;x++) {
+ for(y=0;y<xsize;y++)
+ code_table[j++] = (x << 4) | y;
+ }
+ huff_code_table[i] = code_table;
+ }
+ for(i=0;i<2;i++) {
+ init_vlc(&huff_quad_vlc[i], i == 0 ? 7 : 4, 16,
+ mpa_quad_bits[i], 1, 1, mpa_quad_codes[i], 1, 1);
+ }
+
+ for(i=0;i<9;i++) {
+ k = 0;
+ for(j=0;j<22;j++) {
+ band_index_long[i][j] = k;
+ k += band_size_long[i][j];
+ }
+ band_index_long[i][22] = k;
+ }
+
+ /* compute n ^ (4/3) and store it in mantissa/exp format */
+ table_4_3_exp = av_mallocz(TABLE_4_3_SIZE *
+ sizeof(table_4_3_exp[0]));
+ if (!table_4_3_exp)
+ return -1;
+ table_4_3_value = av_mallocz(TABLE_4_3_SIZE *
+ sizeof(table_4_3_value[0]));
+ if (!table_4_3_value) {
+ free(table_4_3_exp);
+ return -1;
+ }
+
+ for(i=1;i<TABLE_4_3_SIZE;i++) {
+ double f, fm;
+ int e, m;
+ f = pow((double)i, 4.0 / 3.0);
+ fm = frexp(f, &e);
+ m = FIXR(2 * fm);
+#if FRAC_BITS <= 15
+ if ((unsigned short)m != m)
+ m = 65535;
+#endif
+ /* normalized to FRAC_BITS */
+ table_4_3_value[i] = m;
+ table_4_3_exp[i] = e - 1;
+ }
+
+
+ for(i=0;i<7;i++) {
+ float f;
+ int v;
+ if (i != 6) {
+ f = tan((double)i * M_PI / 12.0);
+ v = FIXR(f / (1.0 + f));
+ } else {
+ v = FIXR(1.0);
+ }
+ is_table[0][i] = v;
+ is_table[1][6 - i] = v;
+ }
+ /* invalid values */
+ for(i=7;i<16;i++)
+ is_table[0][i] = is_table[1][i] = 0.0;
+
+ for(i=0;i<16;i++) {
+ double f;
+ int e, k;
+
+ for(j=0;j<2;j++) {
+ e = -(j + 1) * ((i + 1) >> 1);
+ f = pow(2.0, e / 4.0);
+ k = i & 1;
+ is_table_lsf[j][k ^ 1][i] = FIXR(f);
+ is_table_lsf[j][k][i] = FIXR(1.0);
+ dprintf("is_table_lsf %d %d: %x %x\n",
+ i, j, is_table_lsf[j][0][i], is_table_lsf[j][1][i]);
+ }
+ }
+
+ for(i=0;i<8;i++) {
+ float ci, cs, ca;
+ ci = ci_table[i];
+ cs = 1.0 / sqrt(1.0 + ci * ci);
+ ca = cs * ci;
+ csa_table[i][0] = FIX(cs);
+ csa_table[i][1] = FIX(ca);
+ }
+
+ /* compute mdct windows */
+ for(i=0;i<36;i++) {
+ int v;
+ v = FIXR(sin(M_PI * (i + 0.5) / 36.0));
+ mdct_win[0][i] = v;
+ mdct_win[1][i] = v;
+ mdct_win[3][i] = v;
+ }
+ for(i=0;i<6;i++) {
+ mdct_win[1][18 + i] = FIXR(1.0);
+ mdct_win[1][24 + i] = FIXR(sin(M_PI * ((i + 6) + 0.5) / 12.0));
+ mdct_win[1][30 + i] = FIXR(0.0);
+
+ mdct_win[3][i] = FIXR(0.0);
+ mdct_win[3][6 + i] = FIXR(sin(M_PI * (i + 0.5) / 12.0));
+ mdct_win[3][12 + i] = FIXR(1.0);
+ }
+
+ for(i=0;i<12;i++)
+ mdct_win[2][i] = FIXR(sin(M_PI * (i + 0.5) / 12.0));
+
+ /* NOTE: we do frequency inversion adter the MDCT by changing
+ the sign of the right window coefs */
+ for(j=0;j<4;j++) {
+ for(i=0;i<36;i+=2) {
+ mdct_win[j + 4][i] = mdct_win[j][i];
+ mdct_win[j + 4][i + 1] = -mdct_win[j][i + 1];
+ }
+ }
+
+#if defined(DEBUG)
+ for(j=0;j<8;j++) {
+ printf("win%d=\n", j);
+ for(i=0;i<36;i++)
+ printf("%f, ", (double)mdct_win[j][i] / FRAC_ONE);
+ printf("\n");
+ }
+#endif
init = 1;
- make_decode_tables(32767);
- init_layer2();
- init_layer3(SBLIMIT);
}
s->inbuf_index = 0;
s->inbuf = &s->inbuf1[s->inbuf_index][BACKSTEP_SIZE];
s->inbuf_ptr = s->inbuf;
-
+#ifdef DEBUG
+ s->frame_count = 0;
+#endif
return 0;
}
+/* tab[i][j] = 1.0 / (2.0 * cos(pi*(2*k+1) / 2^(6 - j))) */;
+
+/* cos(i*pi/64) */
+
+#define COS0_0 FIXR(0.50060299823519630134)
+#define COS0_1 FIXR(0.50547095989754365998)
+#define COS0_2 FIXR(0.51544730992262454697)
+#define COS0_3 FIXR(0.53104259108978417447)
+#define COS0_4 FIXR(0.55310389603444452782)
+#define COS0_5 FIXR(0.58293496820613387367)
+#define COS0_6 FIXR(0.62250412303566481615)
+#define COS0_7 FIXR(0.67480834145500574602)
+#define COS0_8 FIXR(0.74453627100229844977)
+#define COS0_9 FIXR(0.83934964541552703873)
+#define COS0_10 FIXR(0.97256823786196069369)
+#define COS0_11 FIXR(1.16943993343288495515)
+#define COS0_12 FIXR(1.48416461631416627724)
+#define COS0_13 FIXR(2.05778100995341155085)
+#define COS0_14 FIXR(3.40760841846871878570)
+#define COS0_15 FIXR(10.19000812354805681150)
+
+#define COS1_0 FIXR(0.50241928618815570551)
+#define COS1_1 FIXR(0.52249861493968888062)
+#define COS1_2 FIXR(0.56694403481635770368)
+#define COS1_3 FIXR(0.64682178335999012954)
+#define COS1_4 FIXR(0.78815462345125022473)
+#define COS1_5 FIXR(1.06067768599034747134)
+#define COS1_6 FIXR(1.72244709823833392782)
+#define COS1_7 FIXR(5.10114861868916385802)
+
+#define COS2_0 FIXR(0.50979557910415916894)
+#define COS2_1 FIXR(0.60134488693504528054)
+#define COS2_2 FIXR(0.89997622313641570463)
+#define COS2_3 FIXR(2.56291544774150617881)
+
+#define COS3_0 FIXR(0.54119610014619698439)
+#define COS3_1 FIXR(1.30656296487637652785)
+
+#define COS4_0 FIXR(0.70710678118654752439)
+
+/* butterfly operator */
+#define BF(a, b, c)\
+{\
+ tmp0 = tab[a] + tab[b];\
+ tmp1 = tab[a] - tab[b];\
+ tab[a] = tmp0;\
+ tab[b] = MULL(tmp1, c);\
+}
+
+#define BF1(a, b, c, d)\
+{\
+ BF(a, b, COS4_0);\
+ BF(c, d, -COS4_0);\
+ tab[c] += tab[d];\
+}
+
+#define BF2(a, b, c, d)\
+{\
+ BF(a, b, COS4_0);\
+ BF(c, d, -COS4_0);\
+ tab[c] += tab[d];\
+ tab[a] += tab[c];\
+ tab[c] += tab[b];\
+ tab[b] += tab[d];\
+}
+
+#define ADD(a, b) tab[a] += tab[b]
+
+/* DCT32 without 1/sqrt(2) coef zero scaling. */
+static void dct32(INT32 *out, INT32 *tab)
+{
+ int tmp0, tmp1;
+
+ /* pass 1 */
+ BF(0, 31, COS0_0);
+ BF(1, 30, COS0_1);
+ BF(2, 29, COS0_2);
+ BF(3, 28, COS0_3);
+ BF(4, 27, COS0_4);
+ BF(5, 26, COS0_5);
+ BF(6, 25, COS0_6);
+ BF(7, 24, COS0_7);
+ BF(8, 23, COS0_8);
+ BF(9, 22, COS0_9);
+ BF(10, 21, COS0_10);
+ BF(11, 20, COS0_11);
+ BF(12, 19, COS0_12);
+ BF(13, 18, COS0_13);
+ BF(14, 17, COS0_14);
+ BF(15, 16, COS0_15);
+
+ /* pass 2 */
+ BF(0, 15, COS1_0);
+ BF(1, 14, COS1_1);
+ BF(2, 13, COS1_2);
+ BF(3, 12, COS1_3);
+ BF(4, 11, COS1_4);
+ BF(5, 10, COS1_5);
+ BF(6, 9, COS1_6);
+ BF(7, 8, COS1_7);
+
+ BF(16, 31, -COS1_0);
+ BF(17, 30, -COS1_1);
+ BF(18, 29, -COS1_2);
+ BF(19, 28, -COS1_3);
+ BF(20, 27, -COS1_4);
+ BF(21, 26, -COS1_5);
+ BF(22, 25, -COS1_6);
+ BF(23, 24, -COS1_7);
+
+ /* pass 3 */
+ BF(0, 7, COS2_0);
+ BF(1, 6, COS2_1);
+ BF(2, 5, COS2_2);
+ BF(3, 4, COS2_3);
+
+ BF(8, 15, -COS2_0);
+ BF(9, 14, -COS2_1);
+ BF(10, 13, -COS2_2);
+ BF(11, 12, -COS2_3);
+
+ BF(16, 23, COS2_0);
+ BF(17, 22, COS2_1);
+ BF(18, 21, COS2_2);
+ BF(19, 20, COS2_3);
+
+ BF(24, 31, -COS2_0);
+ BF(25, 30, -COS2_1);
+ BF(26, 29, -COS2_2);
+ BF(27, 28, -COS2_3);
+
+ /* pass 4 */
+ BF(0, 3, COS3_0);
+ BF(1, 2, COS3_1);
+
+ BF(4, 7, -COS3_0);
+ BF(5, 6, -COS3_1);
+
+ BF(8, 11, COS3_0);
+ BF(9, 10, COS3_1);
+
+ BF(12, 15, -COS3_0);
+ BF(13, 14, -COS3_1);
+
+ BF(16, 19, COS3_0);
+ BF(17, 18, COS3_1);
+
+ BF(20, 23, -COS3_0);
+ BF(21, 22, -COS3_1);
+
+ BF(24, 27, COS3_0);
+ BF(25, 26, COS3_1);
+
+ BF(28, 31, -COS3_0);
+ BF(29, 30, -COS3_1);
+
+ /* pass 5 */
+ BF1(0, 1, 2, 3);
+ BF2(4, 5, 6, 7);
+ BF1(8, 9, 10, 11);
+ BF2(12, 13, 14, 15);
+ BF1(16, 17, 18, 19);
+ BF2(20, 21, 22, 23);
+ BF1(24, 25, 26, 27);
+ BF2(28, 29, 30, 31);
+
+ /* pass 6 */
+
+ ADD( 8, 12);
+ ADD(12, 10);
+ ADD(10, 14);
+ ADD(14, 9);
+ ADD( 9, 13);
+ ADD(13, 11);
+ ADD(11, 15);
+
+ out[ 0] = tab[0];
+ out[16] = tab[1];
+ out[ 8] = tab[2];
+ out[24] = tab[3];
+ out[ 4] = tab[4];
+ out[20] = tab[5];
+ out[12] = tab[6];
+ out[28] = tab[7];
+ out[ 2] = tab[8];
+ out[18] = tab[9];
+ out[10] = tab[10];
+ out[26] = tab[11];
+ out[ 6] = tab[12];
+ out[22] = tab[13];
+ out[14] = tab[14];
+ out[30] = tab[15];
+
+ ADD(24, 28);
+ ADD(28, 26);
+ ADD(26, 30);
+ ADD(30, 25);
+ ADD(25, 29);
+ ADD(29, 27);
+ ADD(27, 31);
+
+ out[ 1] = tab[16] + tab[24];
+ out[17] = tab[17] + tab[25];
+ out[ 9] = tab[18] + tab[26];
+ out[25] = tab[19] + tab[27];
+ out[ 5] = tab[20] + tab[28];
+ out[21] = tab[21] + tab[29];
+ out[13] = tab[22] + tab[30];
+ out[29] = tab[23] + tab[31];
+ out[ 3] = tab[24] + tab[20];
+ out[19] = tab[25] + tab[21];
+ out[11] = tab[26] + tab[22];
+ out[27] = tab[27] + tab[23];
+ out[ 7] = tab[28] + tab[18];
+ out[23] = tab[29] + tab[19];
+ out[15] = tab[30] + tab[17];
+ out[31] = tab[31];
+}
+
+#define OUT_SHIFT (WFRAC_BITS + FRAC_BITS - 15)
+
+#if FRAC_BITS <= 15
+
+#define OUT_SAMPLE(sum)\
+{\
+ int sum1;\
+ sum1 = (sum + (1 << (OUT_SHIFT - 1))) >> OUT_SHIFT;\
+ if (sum1 < -32768)\
+ sum1 = -32768;\
+ else if (sum1 > 32767)\
+ sum1 = 32767;\
+ *samples = sum1;\
+ samples += incr;\
+}
+
+#define SUM8(off, op) \
+{ \
+ sum op w[0 * 64 + off] * p[0 * 64];\
+ sum op w[1 * 64 + off] * p[1 * 64];\
+ sum op w[2 * 64 + off] * p[2 * 64];\
+ sum op w[3 * 64 + off] * p[3 * 64];\
+ sum op w[4 * 64 + off] * p[4 * 64];\
+ sum op w[5 * 64 + off] * p[5 * 64];\
+ sum op w[6 * 64 + off] * p[6 * 64];\
+ sum op w[7 * 64 + off] * p[7 * 64];\
+}
+
+#else
+
+#define OUT_SAMPLE(sum)\
+{\
+ int sum1;\
+ sum1 = (int)((sum + (INT64_C(1) << (OUT_SHIFT - 1))) >> OUT_SHIFT);\
+ if (sum1 < -32768)\
+ sum1 = -32768;\
+ else if (sum1 > 32767)\
+ sum1 = 32767;\
+ *samples = sum1;\
+ samples += incr;\
+}
+
+#define SUM8(off, op) \
+{ \
+ sum op MUL64(w[0 * 64 + off], p[0 * 64]);\
+ sum op MUL64(w[1 * 64 + off], p[1 * 64]);\
+ sum op MUL64(w[2 * 64 + off], p[2 * 64]);\
+ sum op MUL64(w[3 * 64 + off], p[3 * 64]);\
+ sum op MUL64(w[4 * 64 + off], p[4 * 64]);\
+ sum op MUL64(w[5 * 64 + off], p[5 * 64]);\
+ sum op MUL64(w[6 * 64 + off], p[6 * 64]);\
+ sum op MUL64(w[7 * 64 + off], p[7 * 64]);\
+}
+
+#endif
+
+/* 32 sub band synthesis filter. Input: 32 sub band samples, Output:
+ 32 samples. */
+/* XXX: optimize by avoiding ring buffer usage */
+static void synth_filter(MPADecodeContext *s1,
+ int ch, INT16 *samples, int incr,
+ INT32 sb_samples[SBLIMIT])
+{
+ INT32 tmp[32];
+ register MPA_INT *synth_buf, *p;
+ register MPA_INT *w;
+ int j, offset, v;
+#if FRAC_BITS <= 15
+ int sum;
+#else
+ INT64 sum;
+#endif
+
+ dct32(tmp, sb_samples);
+
+ offset = s1->synth_buf_offset[ch];
+ synth_buf = s1->synth_buf[ch] + offset;
+
+ for(j=0;j<32;j++) {
+ v = tmp[j];
+#if FRAC_BITS <= 15
+ if (v > 32767)
+ v = 32767;
+ else if (v < -32768)
+ v = -32768;
+#endif
+ synth_buf[j] = v;
+ }
+ /* copy to avoid wrap */
+ memcpy(synth_buf + 512, synth_buf, 32 * sizeof(MPA_INT));
+
+ w = window;
+ for(j=0;j<16;j++) {
+ sum = 0;
+ p = synth_buf + 16 + j; /* 0-15 */
+ SUM8(0, +=);
+ p = synth_buf + 48 - j; /* 32-47 */
+ SUM8(32, -=);
+ OUT_SAMPLE(sum);
+ w++;
+ }
+
+ p = synth_buf + 32; /* 48 */
+ sum = 0;
+ SUM8(32, -=);
+ OUT_SAMPLE(sum);
+ w++;
+
+ for(j=17;j<32;j++) {
+ sum = 0;
+ p = synth_buf + 48 - j; /* 17-31 */
+ SUM8(0, -=);
+ p = synth_buf + 16 + j; /* 49-63 */
+ SUM8(32, -=);
+ OUT_SAMPLE(sum);
+ w++;
+ }
+ offset = (offset - 32) & 511;
+ s1->synth_buf_offset[ch] = offset;
+}
+
+/* cos(pi*i/24) */
+#define C1 FIXR(0.99144486137381041114)
+#define C3 FIXR(0.92387953251128675612)
+#define C5 FIXR(0.79335334029123516458)
+#define C7 FIXR(0.60876142900872063941)
+#define C9 FIXR(0.38268343236508977173)
+#define C11 FIXR(0.13052619222005159154)
+
+/* 12 points IMDCT. We compute it "by hand" by factorizing obvious
+ cases. */
+static void imdct12(int *out, int *in)
+{
+ int tmp;
+ INT64 in1_3, in1_9, in4_3, in4_9;
+
+ in1_3 = MUL64(in[1], C3);
+ in1_9 = MUL64(in[1], C9);
+ in4_3 = MUL64(in[4], C3);
+ in4_9 = MUL64(in[4], C9);
+
+ tmp = FRAC_RND(MUL64(in[0], C7) - in1_3 - MUL64(in[2], C11) +
+ MUL64(in[3], C1) - in4_9 - MUL64(in[5], C5));
+ out[0] = tmp;
+ out[5] = -tmp;
+ tmp = FRAC_RND(MUL64(in[0] - in[3], C9) - in1_3 +
+ MUL64(in[2] + in[5], C3) - in4_9);
+ out[1] = tmp;
+ out[4] = -tmp;
+ tmp = FRAC_RND(MUL64(in[0], C11) - in1_9 + MUL64(in[2], C7) -
+ MUL64(in[3], C5) + in4_3 - MUL64(in[5], C1));
+ out[2] = tmp;
+ out[3] = -tmp;
+ tmp = FRAC_RND(MUL64(-in[0], C5) + in1_9 + MUL64(in[2], C1) +
+ MUL64(in[3], C11) - in4_3 - MUL64(in[5], C7));
+ out[6] = tmp;
+ out[11] = tmp;
+ tmp = FRAC_RND(MUL64(-in[0] + in[3], C3) - in1_9 +
+ MUL64(in[2] + in[5], C9) + in4_3);
+ out[7] = tmp;
+ out[10] = tmp;
+ tmp = FRAC_RND(-MUL64(in[0], C1) - in1_3 - MUL64(in[2], C5) -
+ MUL64(in[3], C7) - in4_9 - MUL64(in[5], C11));
+ out[8] = tmp;
+ out[9] = tmp;
+}
+
+#undef C1
+#undef C3
+#undef C5
+#undef C7
+#undef C9
+#undef C11
+
+/* cos(pi*i/18) */
+#define C1 FIXR(0.98480775301220805936)
+#define C2 FIXR(0.93969262078590838405)
+#define C3 FIXR(0.86602540378443864676)
+#define C4 FIXR(0.76604444311897803520)
+#define C5 FIXR(0.64278760968653932632)
+#define C6 FIXR(0.5)
+#define C7 FIXR(0.34202014332566873304)
+#define C8 FIXR(0.17364817766693034885)
+
+/* 0.5 / cos(pi*(2*i+1)/36) */
+static const int icos36[9] = {
+ FIXR(0.50190991877167369479),
+ FIXR(0.51763809020504152469),
+ FIXR(0.55168895948124587824),
+ FIXR(0.61038729438072803416),
+ FIXR(0.70710678118654752439),
+ FIXR(0.87172339781054900991),
+ FIXR(1.18310079157624925896),
+ FIXR(1.93185165257813657349),
+ FIXR(5.73685662283492756461),
+};
+
+static const int icos72[18] = {
+ /* 0.5 / cos(pi*(2*i+19)/72) */
+ FIXR(0.74009361646113053152),
+ FIXR(0.82133981585229078570),
+ FIXR(0.93057949835178895673),
+ FIXR(1.08284028510010010928),
+ FIXR(1.30656296487637652785),
+ FIXR(1.66275476171152078719),
+ FIXR(2.31011315767264929558),
+ FIXR(3.83064878777019433457),
+ FIXR(11.46279281302667383546),
+
+ /* 0.5 / cos(pi*(2*(i + 18) +19)/72) */
+ FIXR(-0.67817085245462840086),
+ FIXR(-0.63023620700513223342),
+ FIXR(-0.59284452371708034528),
+ FIXR(-0.56369097343317117734),
+ FIXR(-0.54119610014619698439),
+ FIXR(-0.52426456257040533932),
+ FIXR(-0.51213975715725461845),
+ FIXR(-0.50431448029007636036),
+ FIXR(-0.50047634258165998492),
+};
+
+/* using Lee like decomposition followed by hand coded 9 points DCT */
+static void imdct36(int *out, int *in)
+{
+ int i, j, t0, t1, t2, t3, s0, s1, s2, s3;
+ int tmp[18], *tmp1, *in1;
+ INT64 in3_3, in6_6;
+
+ for(i=17;i>=1;i--)
+ in[i] += in[i-1];
+ for(i=17;i>=3;i-=2)
+ in[i] += in[i-2];
+
+ for(j=0;j<2;j++) {
+ tmp1 = tmp + j;
+ in1 = in + j;
+
+ in3_3 = MUL64(in1[2*3], C3);
+ in6_6 = MUL64(in1[2*6], C6);
+
+ tmp1[0] = FRAC_RND(MUL64(in1[2*1], C1) + in3_3 +
+ MUL64(in1[2*5], C5) + MUL64(in1[2*7], C7));
+ tmp1[2] = in1[2*0] + FRAC_RND(MUL64(in1[2*2], C2) +
+ MUL64(in1[2*4], C4) + in6_6 +
+ MUL64(in1[2*8], C8));
+ tmp1[4] = FRAC_RND(MUL64(in1[2*1] - in1[2*5] - in1[2*7], C3));
+ tmp1[6] = FRAC_RND(MUL64(in1[2*2] - in1[2*4] - in1[2*8], C6)) -
+ in1[2*6] + in1[2*0];
+ tmp1[8] = FRAC_RND(MUL64(in1[2*1], C5) - in3_3 -
+ MUL64(in1[2*5], C7) + MUL64(in1[2*7], C1));
+ tmp1[10] = in1[2*0] + FRAC_RND(MUL64(-in1[2*2], C8) -
+ MUL64(in1[2*4], C2) + in6_6 +
+ MUL64(in1[2*8], C4));
+ tmp1[12] = FRAC_RND(MUL64(in1[2*1], C7) - in3_3 +
+ MUL64(in1[2*5], C1) -
+ MUL64(in1[2*7], C5));
+ tmp1[14] = in1[2*0] + FRAC_RND(MUL64(-in1[2*2], C4) +
+ MUL64(in1[2*4], C8) + in6_6 -
+ MUL64(in1[2*8], C2));
+ tmp1[16] = in1[2*0] - in1[2*2] + in1[2*4] - in1[2*6] + in1[2*8];
+ }
+
+ i = 0;
+ for(j=0;j<4;j++) {
+ t0 = tmp[i];
+ t1 = tmp[i + 2];
+ s0 = t1 + t0;
+ s2 = t1 - t0;
+
+ t2 = tmp[i + 1];
+ t3 = tmp[i + 3];
+ s1 = MULL(t3 + t2, icos36[j]);
+ s3 = MULL(t3 - t2, icos36[8 - j]);
+
+ t0 = MULL(s0 + s1, icos72[9 + 8 - j]);
+ t1 = MULL(s0 - s1, icos72[8 - j]);
+ out[18 + 9 + j] = t0;
+ out[18 + 8 - j] = t0;
+ out[9 + j] = -t1;
+ out[8 - j] = t1;
+
+ t0 = MULL(s2 + s3, icos72[9+j]);
+ t1 = MULL(s2 - s3, icos72[j]);
+ out[18 + 9 + (8 - j)] = t0;
+ out[18 + j] = t0;
+ out[9 + (8 - j)] = -t1;
+ out[j] = t1;
+ i += 4;
+ }
+
+ s0 = tmp[16];
+ s1 = MULL(tmp[17], icos36[4]);
+ t0 = MULL(s0 + s1, icos72[9 + 4]);
+ t1 = MULL(s0 - s1, icos72[4]);
+ out[18 + 9 + 4] = t0;
+ out[18 + 8 - 4] = t0;
+ out[9 + 4] = -t1;
+ out[8 - 4] = t1;
+}
+
/* fast header check for resync */
static int check_header(UINT32 header)
{
@@ -95,9 +953,8 @@ static int check_header(UINT32 header)
/* layer check */
if (((header >> 17) & 3) == 0)
return -1;
- /* bit rate : currently no free format supported */
- if (((header >> 12) & 0xf) == 0xf ||
- ((header >> 12) & 0xf) == 0x0)
+ /* bit rate */
+ if (((header >> 12) & 0xf) == 0xf)
return -1;
/* frequency */
if (((header >> 10) & 3) == 3)
@@ -105,123 +962,1281 @@ static int check_header(UINT32 header)
return 0;
}
+/* header + layer + bitrate + freq + lsf/mpeg25 */
+#define SAME_HEADER_MASK \
+ (0xffe00000 | (3 << 17) | (0xf << 12) | (3 << 10) | (3 << 19))
+
/* header decoding. MUST check the header before because no
- consistency check is done there */
-static void decode_header(MPADecodeContext *s, UINT32 header)
+ consistency check is done there. Return 1 if free format found and
+ that the frame size must be computed externally */
+static int decode_header(MPADecodeContext *s, UINT32 header)
{
- struct frame *fr = &s->mpstr.fr;
- int sample_rate, frame_size;
-
+ int sample_rate, frame_size, mpeg25, padding;
+ int sample_rate_index, bitrate_index;
if (header & (1<<20)) {
- fr->lsf = (header & (1<<19)) ? 0 : 1;
- fr->mpeg25 = 0;
+ s->lsf = (header & (1<<19)) ? 0 : 1;
+ mpeg25 = 0;
} else {
- fr->lsf = 1;
- fr->mpeg25 = 1;
+ s->lsf = 1;
+ mpeg25 = 1;
}
s->layer = 4 - ((header >> 17) & 3);
/* extract frequency */
- fr->sampling_frequency = ((header >> 10) & 3);
- sample_rate = mp_freq_tab[fr->sampling_frequency] >> (fr->lsf + fr->mpeg25);
- fr->sampling_frequency += 3 * (fr->lsf + fr->mpeg25);
-
- s->error_protection = ((header>>16) & 1) ^ 1;
+ sample_rate_index = (header >> 10) & 3;
+ sample_rate = mpa_freq_tab[sample_rate_index] >> (s->lsf + mpeg25);
+ sample_rate_index += 3 * (s->lsf + mpeg25);
+ s->sample_rate_index = sample_rate_index;
+ s->error_protection = ((header >> 16) & 1) ^ 1;
- fr->bitrate_index = ((header>>12)&0xf);
- fr->padding = ((header>>9)&0x1);
- fr->extension = ((header>>8)&0x1);
- fr->mode = ((header>>6)&0x3);
- fr->mode_ext = ((header>>4)&0x3);
- fr->copyright = ((header>>3)&0x1);
- fr->original = ((header>>2)&0x1);
- fr->emphasis = header & 0x3;
-
- fr->stereo = (fr->mode == MPG_MD_MONO) ? 1 : 2;
+ bitrate_index = (header >> 12) & 0xf;
+ padding = (header >> 9) & 1;
+ //extension = (header >> 8) & 1;
+ s->mode = (header >> 6) & 3;
+ s->mode_ext = (header >> 4) & 3;
+ //copyright = (header >> 3) & 1;
+ //original = (header >> 2) & 1;
+ //emphasis = header & 3;
+ if (s->mode == MPA_MONO)
+ s->nb_channels = 1;
+ else
+ s->nb_channels = 2;
- frame_size = mp_bitrate_tab[fr->lsf][s->layer - 1][fr->bitrate_index];
- s->bit_rate = frame_size * 1000;
- switch(s->layer) {
- case 1:
- frame_size = (frame_size * 12000) / sample_rate;
- frame_size = ((frame_size + fr->padding) << 2);
- break;
- case 2:
- frame_size = (frame_size * 144000) / sample_rate;
- frame_size += fr->padding;
- break;
- case 3:
- frame_size = (frame_size * 144000) / (sample_rate << fr->lsf);
- frame_size += fr->padding;
- break;
+ if (bitrate_index != 0) {
+ frame_size = mpa_bitrate_tab[s->lsf][s->layer - 1][bitrate_index];
+ s->bit_rate = frame_size * 1000;
+ switch(s->layer) {
+ case 1:
+ frame_size = (frame_size * 12000) / sample_rate;
+ frame_size = (frame_size + padding) * 4;
+ break;
+ case 2:
+ frame_size = (frame_size * 144000) / sample_rate;
+ frame_size += padding;
+ break;
+ default:
+ case 3:
+ frame_size = (frame_size * 144000) / (sample_rate << s->lsf);
+ frame_size += padding;
+ break;
+ }
+ s->frame_size = frame_size;
+ } else {
+ /* if no frame size computed, signal it */
+ if (!s->free_format_frame_size)
+ return 1;
+ /* free format: compute bitrate and real frame size from the
+ frame size we extracted by reading the bitstream */
+ s->frame_size = s->free_format_frame_size;
+ switch(s->layer) {
+ case 1:
+ s->frame_size += padding * 4;
+ s->bit_rate = (s->frame_size * sample_rate) / 48000;
+ break;
+ case 2:
+ s->frame_size += padding;
+ s->bit_rate = (s->frame_size * sample_rate) / 144000;
+ break;
+ default:
+ case 3:
+ s->frame_size += padding;
+ s->bit_rate = (s->frame_size * (sample_rate << s->lsf)) / 144000;
+ break;
+ }
}
- s->frame_size = frame_size;
s->sample_rate = sample_rate;
-
-#if 0
- printf("layer%d, %d Hz, %d kbits/s, %s\n",
- s->layer, s->sample_rate, s->bit_rate, fr->stereo ? "stereo" : "mono");
+
+#ifdef DEBUG
+ printf("layer%d, %d Hz, %d kbits/s, ",
+ s->layer, s->sample_rate, s->bit_rate);
+ if (s->nb_channels == 2) {
+ if (s->layer == 3) {
+ if (s->mode_ext & MODE_EXT_MS_STEREO)
+ printf("ms-");
+ if (s->mode_ext & MODE_EXT_I_STEREO)
+ printf("i-");
+ }
+ printf("stereo");
+ } else {
+ printf("mono");
+ }
+ printf("\n");
#endif
+ return 0;
}
-static int mp_decode_frame(MPADecodeContext *s,
- short *samples)
+/* return the number of decoded frames */
+static int mp_decode_layer1(MPADecodeContext *s)
{
- int nb_bytes;
+ int bound, i, v, n, ch, j, mant;
+ UINT8 allocation[MPA_MAX_CHANNELS][SBLIMIT];
+ UINT8 scale_factors[MPA_MAX_CHANNELS][SBLIMIT];
+
+ if (s->mode == MPA_JSTEREO)
+ bound = (s->mode_ext + 1) * 4;
+ else
+ bound = SBLIMIT;
+
+ /* allocation bits */
+ for(i=0;i<bound;i++) {
+ for(ch=0;ch<s->nb_channels;ch++) {
+ allocation[ch][i] = get_bits(&s->gb, 4);
+ }
+ }
+ for(i=bound;i<SBLIMIT;i++) {
+ allocation[0][i] = get_bits(&s->gb, 4);
+ }
+
+ /* scale factors */
+ for(i=0;i<bound;i++) {
+ for(ch=0;ch<s->nb_channels;ch++) {
+ if (allocation[ch][i])
+ scale_factors[ch][i] = get_bits(&s->gb, 6);
+ }
+ }
+ for(i=bound;i<SBLIMIT;i++) {
+ if (allocation[0][i]) {
+ scale_factors[0][i] = get_bits(&s->gb, 6);
+ scale_factors[1][i] = get_bits(&s->gb, 6);
+ }
+ }
- init_get_bits(&s->gb, s->inbuf + HEADER_SIZE, s->inbuf_ptr - s->inbuf - HEADER_SIZE);
+ /* compute samples */
+ for(j=0;j<12;j++) {
+ for(i=0;i<bound;i++) {
+ for(ch=0;ch<s->nb_channels;ch++) {
+ n = allocation[ch][i];
+ if (n) {
+ mant = get_bits(&s->gb, n + 1);
+ v = l1_unscale(n, mant, scale_factors[ch][i]);
+ } else {
+ v = 0;
+ }
+ s->sb_samples[ch][j][i] = v;
+ }
+ }
+ for(i=bound;i<SBLIMIT;i++) {
+ n = allocation[0][i];
+ if (n) {
+ mant = get_bits(&s->gb, n + 1);
+ v = l1_unscale(n, mant, scale_factors[0][i]);
+ s->sb_samples[0][j][i] = v;
+ v = l1_unscale(n, mant, scale_factors[1][i]);
+ s->sb_samples[1][j][i] = v;
+ } else {
+ s->sb_samples[0][j][i] = 0;
+ s->sb_samples[1][j][i] = 0;
+ }
+ }
+ }
+ return 12;
+}
+
+/* bitrate is in kb/s */
+int l2_select_table(int bitrate, int nb_channels, int freq, int lsf)
+{
+ int ch_bitrate, table;
- /* skip error protection field */
- if (s->error_protection)
- get_bits(&s->gb, 16);
+ ch_bitrate = bitrate / nb_channels;
+ if (!lsf) {
+ if ((freq == 48000 && ch_bitrate >= 56) ||
+ (ch_bitrate >= 56 && ch_bitrate <= 80))
+ table = 0;
+ else if (freq != 48000 && ch_bitrate >= 96)
+ table = 1;
+ else if (freq != 32000 && ch_bitrate <= 48)
+ table = 2;
+ else
+ table = 3;
+ } else {
+ table = 4;
+ }
+ return table;
+}
- /* XXX: horrible: global! */
- gmp = &s->mpstr;
- gmp_s = s;
- gmp_gb = &s->gb;
+static int mp_decode_layer2(MPADecodeContext *s)
+{
+ int sblimit; /* number of used subbands */
+ const unsigned char *alloc_table;
+ int table, bit_alloc_bits, i, j, ch, bound, v;
+ unsigned char bit_alloc[MPA_MAX_CHANNELS][SBLIMIT];
+ unsigned char scale_code[MPA_MAX_CHANNELS][SBLIMIT];
+ unsigned char scale_factors[MPA_MAX_CHANNELS][SBLIMIT][3], *sf;
+ int scale, qindex, bits, steps, k, l, m, b;
- nb_bytes = 0;
- switch(s->layer) {
- case 1:
- do_layer1(&s->mpstr.fr,(unsigned char *)samples, &nb_bytes);
- break;
- case 2:
- do_layer2(&s->mpstr.fr,(unsigned char *)samples, &nb_bytes);
- break;
- case 3:
- do_layer3(&s->mpstr.fr,(unsigned char *)samples, &nb_bytes);
- s->inbuf_index ^= 1;
- s->inbuf = &s->inbuf1[s->inbuf_index][BACKSTEP_SIZE];
- s->old_frame_size = s->frame_size;
- break;
- default:
- break;
+ /* select decoding table */
+ table = l2_select_table(s->bit_rate / 1000, s->nb_channels,
+ s->sample_rate, s->lsf);
+ sblimit = sblimit_table[table];
+ alloc_table = alloc_tables[table];
+
+ if (s->mode == MPA_JSTEREO)
+ bound = (s->mode_ext + 1) * 4;
+ else
+ bound = sblimit;
+
+ dprintf("bound=%d sblimit=%d\n", bound, sblimit);
+ /* parse bit allocation */
+ j = 0;
+ for(i=0;i<bound;i++) {
+ bit_alloc_bits = alloc_table[j];
+ for(ch=0;ch<s->nb_channels;ch++) {
+ bit_alloc[ch][i] = get_bits(&s->gb, bit_alloc_bits);
+ }
+ j += 1 << bit_alloc_bits;
+ }
+ for(i=bound;i<sblimit;i++) {
+ bit_alloc_bits = alloc_table[j];
+ v = get_bits(&s->gb, bit_alloc_bits);
+ bit_alloc[0][i] = v;
+ bit_alloc[1][i] = v;
+ j += 1 << bit_alloc_bits;
}
- return nb_bytes;
+
+#ifdef DEBUG
+ {
+ for(ch=0;ch<s->nb_channels;ch++) {
+ for(i=0;i<sblimit;i++)
+ printf(" %d", bit_alloc[ch][i]);
+ printf("\n");
+ }
+ }
+#endif
+
+ /* scale codes */
+ for(i=0;i<sblimit;i++) {
+ for(ch=0;ch<s->nb_channels;ch++) {
+ if (bit_alloc[ch][i])
+ scale_code[ch][i] = get_bits(&s->gb, 2);
+ }
+ }
+
+ /* scale factors */
+ for(i=0;i<sblimit;i++) {
+ for(ch=0;ch<s->nb_channels;ch++) {
+ if (bit_alloc[ch][i]) {
+ sf = scale_factors[ch][i];
+ switch(scale_code[ch][i]) {
+ default:
+ case 0:
+ sf[0] = get_bits(&s->gb, 6);
+ sf[1] = get_bits(&s->gb, 6);
+ sf[2] = get_bits(&s->gb, 6);
+ break;
+ case 2:
+ sf[0] = get_bits(&s->gb, 6);
+ sf[1] = sf[0];
+ sf[2] = sf[0];
+ break;
+ case 1:
+ sf[0] = get_bits(&s->gb, 6);
+ sf[2] = get_bits(&s->gb, 6);
+ sf[1] = sf[0];
+ break;
+ case 3:
+ sf[0] = get_bits(&s->gb, 6);
+ sf[2] = get_bits(&s->gb, 6);
+ sf[1] = sf[2];
+ break;
+ }
+ }
+ }
+ }
+
+#ifdef DEBUG
+ for(ch=0;ch<s->nb_channels;ch++) {
+ for(i=0;i<sblimit;i++) {
+ if (bit_alloc[ch][i]) {
+ sf = scale_factors[ch][i];
+ printf(" %d %d %d", sf[0], sf[1], sf[2]);
+ } else {
+ printf(" -");
+ }
+ }
+ printf("\n");
+ }
+#endif
+
+ /* samples */
+ for(k=0;k<3;k++) {
+ for(l=0;l<12;l+=3) {
+ j = 0;
+ for(i=0;i<bound;i++) {
+ bit_alloc_bits = alloc_table[j];
+ for(ch=0;ch<s->nb_channels;ch++) {
+ b = bit_alloc[ch][i];
+ if (b) {
+ scale = scale_factors[ch][i][k];
+ qindex = alloc_table[j+b];
+ bits = quant_bits[qindex];
+ if (bits < 0) {
+ /* 3 values at the same time */
+ v = get_bits(&s->gb, -bits);
+ steps = quant_steps[qindex];
+ s->sb_samples[ch][k * 12 + l + 0][i] =
+ l2_unscale_group(steps, v % steps, scale);
+ v = v / steps;
+ s->sb_samples[ch][k * 12 + l + 1][i] =
+ l2_unscale_group(steps, v % steps, scale);
+ v = v / steps;
+ s->sb_samples[ch][k * 12 + l + 2][i] =
+ l2_unscale_group(steps, v, scale);
+ } else {
+ for(m=0;m<3;m++) {
+ v = get_bits(&s->gb, bits);
+ v = l1_unscale(bits - 1, v, scale);
+ s->sb_samples[ch][k * 12 + l + m][i] = v;
+ }
+ }
+ } else {
+ s->sb_samples[ch][k * 12 + l + 0][i] = 0;
+ s->sb_samples[ch][k * 12 + l + 1][i] = 0;
+ s->sb_samples[ch][k * 12 + l + 2][i] = 0;
+ }
+ }
+ /* next subband in alloc table */
+ j += 1 << bit_alloc_bits;
+ }
+ /* XXX: find a way to avoid this duplication of code */
+ for(i=bound;i<sblimit;i++) {
+ bit_alloc_bits = alloc_table[j];
+ b = bit_alloc[0][i];
+ if (b) {
+ int mant, scale0, scale1;
+ scale0 = scale_factors[0][i][k];
+ scale1 = scale_factors[1][i][k];
+ qindex = alloc_table[j+b];
+ bits = quant_bits[qindex];
+ if (bits < 0) {
+ /* 3 values at the same time */
+ v = get_bits(&s->gb, -bits);
+ steps = quant_steps[qindex];
+ mant = v % steps;
+ v = v / steps;
+ s->sb_samples[0][k * 12 + l + 0][i] =
+ l2_unscale_group(steps, mant, scale0);
+ s->sb_samples[1][k * 12 + l + 0][i] =
+ l2_unscale_group(steps, mant, scale1);
+ mant = v % steps;
+ v = v / steps;
+ s->sb_samples[0][k * 12 + l + 1][i] =
+ l2_unscale_group(steps, mant, scale0);
+ s->sb_samples[1][k * 12 + l + 1][i] =
+ l2_unscale_group(steps, mant, scale1);
+ s->sb_samples[0][k * 12 + l + 2][i] =
+ l2_unscale_group(steps, v, scale0);
+ s->sb_samples[1][k * 12 + l + 2][i] =
+ l2_unscale_group(steps, v, scale1);
+ } else {
+ for(m=0;m<3;m++) {
+ mant = get_bits(&s->gb, bits);
+ s->sb_samples[0][k * 12 + l + m][i] =
+ l1_unscale(bits - 1, mant, scale0);
+ s->sb_samples[1][k * 12 + l + m][i] =
+ l1_unscale(bits - 1, mant, scale1);
+ }
+ }
+ } else {
+ s->sb_samples[0][k * 12 + l + 0][i] = 0;
+ s->sb_samples[0][k * 12 + l + 1][i] = 0;
+ s->sb_samples[0][k * 12 + l + 2][i] = 0;
+ s->sb_samples[1][k * 12 + l + 0][i] = 0;
+ s->sb_samples[1][k * 12 + l + 1][i] = 0;
+ s->sb_samples[1][k * 12 + l + 2][i] = 0;
+ }
+ /* next subband in alloc table */
+ j += 1 << bit_alloc_bits;
+ }
+ /* fill remaining samples to zero */
+ for(i=sblimit;i<SBLIMIT;i++) {
+ for(ch=0;ch<s->nb_channels;ch++) {
+ s->sb_samples[ch][k * 12 + l + 0][i] = 0;
+ s->sb_samples[ch][k * 12 + l + 1][i] = 0;
+ s->sb_samples[ch][k * 12 + l + 2][i] = 0;
+ }
+ }
+ }
+ }
+ return 3 * 12;
}
/*
- * seek back in the stream for backstep bytes (at most 511 bytes, and
- * at most in last frame). Note that this is slightly incorrect (data
- * can span more than one block!)
+ * Seek back in the stream for backstep bytes (at most 511 bytes)
*/
-int set_pointer(long backstep)
+static void seek_to_maindata(MPADecodeContext *s, long backstep)
{
UINT8 *ptr;
/* compute current position in stream */
- ptr = gmp_gb->buf_ptr - (gmp_gb->bit_cnt >> 3);
+ ptr = s->gb.buf_ptr - (s->gb.bit_cnt >> 3);
/* copy old data before current one */
ptr -= backstep;
- memcpy(ptr, gmp_s->inbuf1[gmp_s->inbuf_index ^ 1] +
- BACKSTEP_SIZE + gmp_s->old_frame_size - backstep, backstep);
+ memcpy(ptr, s->inbuf1[s->inbuf_index ^ 1] +
+ BACKSTEP_SIZE + s->old_frame_size - backstep, backstep);
/* init get bits again */
- init_get_bits(gmp_gb, ptr, gmp_s->frame_size + backstep);
+ init_get_bits(&s->gb, ptr, s->frame_size + backstep);
+ /* prepare next buffer */
+ s->inbuf_index ^= 1;
+ s->inbuf = &s->inbuf1[s->inbuf_index][BACKSTEP_SIZE];
+ s->old_frame_size = s->frame_size;
+}
+
+static inline void lsf_sf_expand(int *slen,
+ int sf, int n1, int n2, int n3)
+{
+ if (n3) {
+ slen[3] = sf % n3;
+ sf /= n3;
+ } else {
+ slen[3] = 0;
+ }
+ if (n2) {
+ slen[2] = sf % n2;
+ sf /= n2;
+ } else {
+ slen[2] = 0;
+ }
+ slen[1] = sf % n1;
+ sf /= n1;
+ slen[0] = sf;
+}
+
+static void exponents_from_scale_factors(MPADecodeContext *s,
+ GranuleDef *g,
+ INT16 *exponents)
+{
+ const UINT8 *bstab, *pretab;
+ int len, i, j, k, l, v0, shift, gain, gains[3];
+ INT16 *exp_ptr;
+
+ exp_ptr = exponents;
+ gain = g->global_gain - 210;
+ shift = g->scalefac_scale + 1;
+
+ bstab = band_size_long[s->sample_rate_index];
+ pretab = mpa_pretab[g->preflag];
+ for(i=0;i<g->long_end;i++) {
+ v0 = gain - ((g->scale_factors[i] + pretab[i]) << shift);
+ len = bstab[i];
+ for(j=len;j>0;j--)
+ *exp_ptr++ = v0;
+ }
+
+ if (g->short_start < 13) {
+ bstab = band_size_short[s->sample_rate_index];
+ gains[0] = gain - (g->subblock_gain[0] << 3);
+ gains[1] = gain - (g->subblock_gain[1] << 3);
+ gains[2] = gain - (g->subblock_gain[2] << 3);
+ k = g->long_end;
+ for(i=g->short_start;i<13;i++) {
+ len = bstab[i];
+ for(l=0;l<3;l++) {
+ v0 = gains[l] - (g->scale_factors[k++] << shift);
+ for(j=len;j>0;j--)
+ *exp_ptr++ = v0;
+ }
+ }
+ }
+}
+
+/* handle n = 0 too */
+static inline int get_bitsz(GetBitContext *s, int n)
+{
+ if (n == 0)
+ return 0;
+ else
+ return get_bits(s, n);
+}
+
+static int huffman_decode(MPADecodeContext *s, GranuleDef *g,
+ INT16 *exponents, int end_pos)
+{
+ int s_index;
+ int linbits, code, x, y, l, v, i, j, k, pos;
+ UINT8 *last_buf_ptr;
+ UINT32 last_bit_buf;
+ int last_bit_cnt;
+ VLC *vlc;
+ UINT8 *code_table;
+
+ /* low frequencies (called big values) */
+ s_index = 0;
+ for(i=0;i<3;i++) {
+ j = g->region_size[i];
+ if (j == 0)
+ continue;
+ /* select vlc table */
+ k = g->table_select[i];
+ l = mpa_huff_data[k][0];
+ linbits = mpa_huff_data[k][1];
+ vlc = &huff_vlc[l];
+ code_table = huff_code_table[l];
+
+ /* read huffcode and compute each couple */
+ for(;j>0;j--) {
+ if (get_bits_count(&s->gb) >= end_pos)
+ break;
+ if (code_table) {
+ code = get_vlc(&s->gb, vlc);
+ if (code < 0)
+ return -1;
+ y = code_table[code];
+ x = y >> 4;
+ y = y & 0x0f;
+ } else {
+ x = 0;
+ y = 0;
+ }
+ dprintf("region=%d n=%d x=%d y=%d exp=%d\n",
+ i, g->region_size[i] - j, x, y, exponents[s_index]);
+ if (x) {
+ if (x == 15)
+ x += get_bitsz(&s->gb, linbits);
+ v = l3_unscale(x, exponents[s_index]);
+ if (get_bits1(&s->gb))
+ v = -v;
+ } else {
+ v = 0;
+ }
+ g->sb_hybrid[s_index++] = v;
+ if (y) {
+ if (y == 15)
+ y += get_bitsz(&s->gb, linbits);
+ v = l3_unscale(y, exponents[s_index]);
+ if (get_bits1(&s->gb))
+ v = -v;
+ } else {
+ v = 0;
+ }
+ g->sb_hybrid[s_index++] = v;
+ }
+ }
+
+ /* high frequencies */
+ vlc = &huff_quad_vlc[g->count1table_select];
+ last_buf_ptr = NULL;
+ last_bit_buf = 0;
+ last_bit_cnt = 0;
+ while (s_index <= 572) {
+ pos = get_bits_count(&s->gb);
+ if (pos >= end_pos) {
+ if (pos > end_pos && last_buf_ptr != NULL) {
+ /* some encoders generate an incorrect size for this
+ part. We must go back into the data */
+ s_index -= 4;
+ s->gb.buf_ptr = last_buf_ptr;
+ s->gb.bit_buf = last_bit_buf;
+ s->gb.bit_cnt = last_bit_cnt;
+ }
+ break;
+ }
+ last_buf_ptr = s->gb.buf_ptr;
+ last_bit_buf = s->gb.bit_buf;
+ last_bit_cnt = s->gb.bit_cnt;
+
+ code = get_vlc(&s->gb, vlc);
+ dprintf("t=%d code=%d\n", g->count1table_select, code);
+ if (code < 0)
+ return -1;
+ for(i=0;i<4;i++) {
+ if (code & (8 >> i)) {
+ /* non zero value. Could use a hand coded function for
+ 'one' value */
+ v = l3_unscale(1, exponents[s_index]);
+ if(get_bits1(&s->gb))
+ v = -v;
+ } else {
+ v = 0;
+ }
+ g->sb_hybrid[s_index++] = v;
+ }
+ }
+ while (s_index < 576)
+ g->sb_hybrid[s_index++] = 0;
return 0;
}
+/* Reorder short blocks from bitstream order to interleaved order. It
+ would be faster to do it in parsing, but the code would be far more
+ complicated */
+static void reorder_block(MPADecodeContext *s, GranuleDef *g)
+{
+ int i, j, k, len;
+ INT32 *ptr, *dst, *ptr1;
+ INT32 tmp[576];
+
+ if (g->block_type != 2)
+ return;
+
+ if (g->switch_point) {
+ if (s->sample_rate_index != 8) {
+ ptr = g->sb_hybrid + 36;
+ } else {
+ ptr = g->sb_hybrid + 48;
+ }
+ } else {
+ ptr = g->sb_hybrid;
+ }
+
+ for(i=g->short_start;i<13;i++) {
+ len = band_size_short[s->sample_rate_index][i];
+ ptr1 = ptr;
+ for(k=0;k<3;k++) {
+ dst = tmp + k;
+ for(j=len;j>0;j--) {
+ *dst = *ptr++;
+ dst += 3;
+ }
+ }
+ memcpy(ptr1, tmp, len * 3 * sizeof(INT32));
+ }
+}
+
+#define ISQRT2 FIXR(0.70710678118654752440)
+
+static void compute_stereo(MPADecodeContext *s,
+ GranuleDef *g0, GranuleDef *g1)
+{
+ int i, j, k, l;
+ INT32 v1, v2;
+ int sf_max, tmp0, tmp1, sf, len, non_zero_found;
+ INT32 (*is_tab)[16];
+ INT32 *tab0, *tab1;
+ int non_zero_found_short[3];
+
+ /* intensity stereo */
+ if (s->mode_ext & MODE_EXT_I_STEREO) {
+ if (!s->lsf) {
+ is_tab = is_table;
+ sf_max = 7;
+ } else {
+ is_tab = is_table_lsf[g1->scalefac_compress & 1];
+ sf_max = 16;
+ }
+
+ tab0 = g0->sb_hybrid + 576;
+ tab1 = g1->sb_hybrid + 576;
+
+ non_zero_found_short[0] = 0;
+ non_zero_found_short[1] = 0;
+ non_zero_found_short[2] = 0;
+ k = (13 - g1->short_start) * 3 + g1->long_end - 3;
+ for(i = 12;i >= g1->short_start;i--) {
+ /* for last band, use previous scale factor */
+ if (i != 11)
+ k -= 3;
+ len = band_size_short[s->sample_rate_index][i];
+ for(l=2;l>=0;l--) {
+ tab0 -= len;
+ tab1 -= len;
+ if (!non_zero_found_short[l]) {
+ /* test if non zero band. if so, stop doing i-stereo */
+ for(j=0;j<len;j++) {
+ if (tab1[j] != 0) {
+ non_zero_found_short[l] = 1;
+ goto found1;
+ }
+ }
+ sf = g1->scale_factors[k + l];
+ if (sf >= sf_max)
+ goto found1;
+
+ v1 = is_tab[0][sf];
+ v2 = is_tab[1][sf];
+ for(j=0;j<len;j++) {
+ tmp0 = tab0[j];
+ tab0[j] = MULL(tmp0, v1);
+ tab1[j] = MULL(tmp0, v2);
+ }
+ } else {
+ found1:
+ if (s->mode_ext & MODE_EXT_MS_STEREO) {
+ /* lower part of the spectrum : do ms stereo
+ if enabled */
+ for(j=0;j<len;j++) {
+ tmp0 = tab0[j];
+ tmp1 = tab1[j];
+ tab0[j] = MULL(tmp0 + tmp1, ISQRT2);
+ tab1[j] = MULL(tmp0 - tmp1, ISQRT2);
+ }
+ }
+ }
+ }
+ }
+
+ non_zero_found = non_zero_found_short[0] |
+ non_zero_found_short[1] |
+ non_zero_found_short[2];
+
+ for(i = g1->long_end - 1;i >= 0;i--) {
+ len = band_size_long[s->sample_rate_index][i];
+ tab0 -= len;
+ tab1 -= len;
+ /* test if non zero band. if so, stop doing i-stereo */
+ if (!non_zero_found) {
+ for(j=0;j<len;j++) {
+ if (tab1[j] != 0) {
+ non_zero_found = 1;
+ goto found2;
+ }
+ }
+ /* for last band, use previous scale factor */
+ k = (i == 21) ? 20 : i;
+ sf = g1->scale_factors[k];
+ if (sf >= sf_max)
+ goto found2;
+ v1 = is_tab[0][sf];
+ v2 = is_tab[1][sf];
+ for(j=0;j<len;j++) {
+ tmp0 = tab0[j];
+ tab0[j] = MULL(tmp0, v1);
+ tab1[j] = MULL(tmp0, v2);
+ }
+ } else {
+ found2:
+ if (s->mode_ext & MODE_EXT_MS_STEREO) {
+ /* lower part of the spectrum : do ms stereo
+ if enabled */
+ for(j=0;j<len;j++) {
+ tmp0 = tab0[j];
+ tmp1 = tab1[j];
+ tab0[j] = MULL(tmp0 + tmp1, ISQRT2);
+ tab1[j] = MULL(tmp0 - tmp1, ISQRT2);
+ }
+ }
+ }
+ }
+ } else if (s->mode_ext & MODE_EXT_MS_STEREO) {
+ /* ms stereo ONLY */
+ /* NOTE: the 1/sqrt(2) normalization factor is included in the
+ global gain */
+ tab0 = g0->sb_hybrid;
+ tab1 = g1->sb_hybrid;
+ for(i=0;i<576;i++) {
+ tmp0 = tab0[i];
+ tmp1 = tab1[i];
+ tab0[i] = tmp0 + tmp1;
+ tab1[i] = tmp0 - tmp1;
+ }
+ }
+}
+
+static void compute_antialias(MPADecodeContext *s,
+ GranuleDef *g)
+{
+ INT32 *ptr, *p0, *p1, *csa;
+ int n, tmp0, tmp1, i, j;
+
+ /* we antialias only "long" bands */
+ if (g->block_type == 2) {
+ if (!g->switch_point)
+ return;
+ /* XXX: check this for 8000Hz case */
+ n = 1;
+ } else {
+ n = SBLIMIT - 1;
+ }
+
+ ptr = g->sb_hybrid + 18;
+ for(i = n;i > 0;i--) {
+ p0 = ptr - 1;
+ p1 = ptr;
+ csa = &csa_table[0][0];
+ for(j=0;j<8;j++) {
+ tmp0 = *p0;
+ tmp1 = *p1;
+ *p0 = FRAC_RND(MUL64(tmp0, csa[0]) - MUL64(tmp1, csa[1]));
+ *p1 = FRAC_RND(MUL64(tmp0, csa[1]) + MUL64(tmp1, csa[0]));
+ p0--;
+ p1++;
+ csa += 2;
+ }
+ ptr += 18;
+ }
+}
+
+static void compute_imdct(MPADecodeContext *s,
+ GranuleDef *g,
+ INT32 *sb_samples,
+ INT32 *mdct_buf)
+{
+ INT32 *ptr, *win, *win1, *buf, *buf2, *out_ptr, *ptr1;
+ INT32 in[6];
+ INT32 out[36];
+ INT32 out2[12];
+ int i, j, k, mdct_long_end, v, sblimit;
+
+ /* find last non zero block */
+ ptr = g->sb_hybrid + 576;
+ ptr1 = g->sb_hybrid + 2 * 18;
+ while (ptr >= ptr1) {
+ ptr -= 6;
+ v = ptr[0] | ptr[1] | ptr[2] | ptr[3] | ptr[4] | ptr[5];
+ if (v != 0)
+ break;
+ }
+ sblimit = ((ptr - g->sb_hybrid) / 18) + 1;
+
+ if (g->block_type == 2) {
+ /* XXX: check for 8000 Hz */
+ if (g->switch_point)
+ mdct_long_end = 2;
+ else
+ mdct_long_end = 0;
+ } else {
+ mdct_long_end = sblimit;
+ }
+
+ buf = mdct_buf;
+ ptr = g->sb_hybrid;
+ for(j=0;j<mdct_long_end;j++) {
+ imdct36(out, ptr);
+ /* apply window & overlap with previous buffer */
+ out_ptr = sb_samples + j;
+ /* select window */
+ if (g->switch_point && j < 2)
+ win1 = mdct_win[0];
+ else
+ win1 = mdct_win[g->block_type];
+ /* select frequency inversion */
+ win = win1 + ((4 * 36) & -(j & 1));
+ for(i=0;i<18;i++) {
+ *out_ptr = MULL(out[i], win[i]) + buf[i];
+ buf[i] = MULL(out[i + 18], win[i + 18]);
+ out_ptr += SBLIMIT;
+ }
+ ptr += 18;
+ buf += 18;
+ }
+ for(j=mdct_long_end;j<sblimit;j++) {
+ for(i=0;i<6;i++) {
+ out[i] = 0;
+ out[6 + i] = 0;
+ out[30+i] = 0;
+ }
+ /* select frequency inversion */
+ win = mdct_win[2] + ((4 * 36) & -(j & 1));
+ buf2 = out + 6;
+ for(k=0;k<3;k++) {
+ /* reorder input for short mdct */
+ ptr1 = ptr + k;
+ for(i=0;i<6;i++) {
+ in[i] = *ptr1;
+ ptr1 += 3;
+ }
+ imdct12(out2, in);
+ /* apply 12 point window and do small overlap */
+ for(i=0;i<6;i++) {
+ buf2[i] = MULL(out2[i], win[i]) + buf2[i];
+ buf2[i + 6] = MULL(out2[i + 6], win[i + 6]);
+ }
+ buf2 += 6;
+ }
+ /* overlap */
+ out_ptr = sb_samples + j;
+ for(i=0;i<18;i++) {
+ *out_ptr = out[i] + buf[i];
+ buf[i] = out[i + 18];
+ out_ptr += SBLIMIT;
+ }
+ ptr += 18;
+ buf += 18;
+ }
+ /* zero bands */
+ for(j=sblimit;j<SBLIMIT;j++) {
+ /* overlap */
+ out_ptr = sb_samples + j;
+ for(i=0;i<18;i++) {
+ *out_ptr = buf[i];
+ buf[i] = 0;
+ out_ptr += SBLIMIT;
+ }
+ buf += 18;
+ }
+}
+
+#ifdef DEBUG
+void sample_dump(int fnum, INT32 *tab, int n)
+{
+ static FILE *files[16], *f;
+ char buf[512];
+
+ f = files[fnum];
+ if (!f) {
+ sprintf(buf, "/tmp/out%d.pcm", fnum);
+ f = fopen(buf, "w");
+ if (!f)
+ return;
+ files[fnum] = f;
+ }
+
+ if (fnum == 0) {
+ int i;
+ static int pos = 0;
+ printf("pos=%d\n", pos);
+ for(i=0;i<n;i++) {
+ printf(" %f", (double)tab[i] / 32768.0);
+ if ((i % 18) == 17)
+ printf("\n");
+ }
+ pos += n;
+ }
+
+ fwrite(tab, 1, n * sizeof(INT32), f);
+}
+#endif
+
+
+/* main layer3 decoding function */
+static int mp_decode_layer3(MPADecodeContext *s)
+{
+ int nb_granules, main_data_begin, private_bits;
+ int gr, ch, blocksplit_flag, i, j, k, n, bits_pos, bits_left;
+ GranuleDef granules[2][2], *g;
+ INT16 exponents[576];
+
+ /* read side info */
+ if (s->lsf) {
+ main_data_begin = get_bits(&s->gb, 8);
+ if (s->nb_channels == 2)
+ private_bits = get_bits(&s->gb, 2);
+ else
+ private_bits = get_bits(&s->gb, 1);
+ nb_granules = 1;
+ } else {
+ main_data_begin = get_bits(&s->gb, 9);
+ if (s->nb_channels == 2)
+ private_bits = get_bits(&s->gb, 3);
+ else
+ private_bits = get_bits(&s->gb, 5);
+ nb_granules = 2;
+ for(ch=0;ch<s->nb_channels;ch++) {
+ granules[ch][0].scfsi = 0; /* all scale factors are transmitted */
+ granules[ch][1].scfsi = get_bits(&s->gb, 4);
+ }
+ }
+
+ for(gr=0;gr<nb_granules;gr++) {
+ for(ch=0;ch<s->nb_channels;ch++) {
+ dprintf("gr=%d ch=%d: side_info\n", gr, ch);
+ g = &granules[ch][gr];
+ g->part2_3_length = get_bits(&s->gb, 12);
+ g->big_values = get_bits(&s->gb, 9);
+ g->global_gain = get_bits(&s->gb, 8);
+ /* if MS stereo only is selected, we precompute the
+ 1/sqrt(2) renormalization factor */
+ if ((s->mode_ext & (MODE_EXT_MS_STEREO | MODE_EXT_I_STEREO)) ==
+ MODE_EXT_MS_STEREO)
+ g->global_gain -= 2;
+ if (s->lsf)
+ g->scalefac_compress = get_bits(&s->gb, 9);
+ else
+ g->scalefac_compress = get_bits(&s->gb, 4);
+ blocksplit_flag = get_bits(&s->gb, 1);
+ if (blocksplit_flag) {
+ g->block_type = get_bits(&s->gb, 2);
+ if (g->block_type == 0)
+ return -1;
+ g->switch_point = get_bits(&s->gb, 1);
+ for(i=0;i<2;i++)
+ g->table_select[i] = get_bits(&s->gb, 5);
+ for(i=0;i<3;i++)
+ g->subblock_gain[i] = get_bits(&s->gb, 3);
+ /* compute huffman coded region sizes */
+ if (g->block_type == 2)
+ g->region_size[0] = (36 / 2);
+ else {
+ if (s->sample_rate_index <= 2)
+ g->region_size[0] = (36 / 2);
+ else if (s->sample_rate_index != 8)
+ g->region_size[0] = (54 / 2);
+ else
+ g->region_size[0] = (108 / 2);
+ }
+ g->region_size[1] = (576 / 2);
+ } else {
+ int region_address1, region_address2, l;
+ g->block_type = 0;
+ g->switch_point = 0;
+ for(i=0;i<3;i++)
+ g->table_select[i] = get_bits(&s->gb, 5);
+ /* compute huffman coded region sizes */
+ region_address1 = get_bits(&s->gb, 4);
+ region_address2 = get_bits(&s->gb, 3);
+ dprintf("region1=%d region2=%d\n",
+ region_address1, region_address2);
+ g->region_size[0] =
+ band_index_long[s->sample_rate_index][region_address1 + 1] >> 1;
+ l = region_address1 + region_address2 + 2;
+ /* should not overflow */
+ if (l > 22)
+ l = 22;
+ g->region_size[1] =
+ band_index_long[s->sample_rate_index][l] >> 1;
+ }
+ /* convert region offsets to region sizes and truncate
+ size to big_values */
+ g->region_size[2] = (576 / 2);
+ j = 0;
+ for(i=0;i<3;i++) {
+ k = g->region_size[i];
+ if (k > g->big_values)
+ k = g->big_values;
+ g->region_size[i] = k - j;
+ j = k;
+ }
+
+ /* compute band indexes */
+ if (g->block_type == 2) {
+ if (g->switch_point) {
+ /* if switched mode, we handle the 36 first samples as
+ long blocks. For 8000Hz, we handle the 48 first
+ exponents as long blocks (XXX: check this!) */
+ if (s->sample_rate_index <= 2)
+ g->long_end = 8;
+ else if (s->sample_rate_index != 8)
+ g->long_end = 6;
+ else
+ g->long_end = 4; /* 8000 Hz */
+
+ if (s->sample_rate_index != 8)
+ g->short_start = 3;
+ else
+ g->short_start = 2;
+ } else {
+ g->long_end = 0;
+ g->short_start = 0;
+ }
+ } else {
+ g->short_start = 13;
+ g->long_end = 22;
+ }
+
+ g->preflag = 0;
+ if (!s->lsf)
+ g->preflag = get_bits(&s->gb, 1);
+ g->scalefac_scale = get_bits(&s->gb, 1);
+ g->count1table_select = get_bits(&s->gb, 1);
+ dprintf("block_type=%d switch_point=%d\n",
+ g->block_type, g->switch_point);
+ }
+ }
+
+ /* now we get bits from the main_data_begin offset */
+ dprintf("seekback: %d\n", main_data_begin);
+ seek_to_maindata(s, main_data_begin);
+
+ for(gr=0;gr<nb_granules;gr++) {
+ for(ch=0;ch<s->nb_channels;ch++) {
+ g = &granules[ch][gr];
+
+ bits_pos = get_bits_count(&s->gb);
+
+ if (!s->lsf) {
+ UINT8 *sc;
+ int slen, slen1, slen2;
+
+ /* MPEG1 scale factors */
+ slen1 = slen_table[0][g->scalefac_compress];
+ slen2 = slen_table[1][g->scalefac_compress];
+ dprintf("slen1=%d slen2=%d\n", slen1, slen2);
+ if (g->block_type == 2) {
+ n = g->switch_point ? 17 : 18;
+ j = 0;
+ for(i=0;i<n;i++)
+ g->scale_factors[j++] = get_bitsz(&s->gb, slen1);
+ for(i=0;i<18;i++)
+ g->scale_factors[j++] = get_bitsz(&s->gb, slen2);
+ for(i=0;i<3;i++)
+ g->scale_factors[j++] = 0;
+ } else {
+ sc = granules[ch][0].scale_factors;
+ j = 0;
+ for(k=0;k<4;k++) {
+ n = (k == 0 ? 6 : 5);
+ if ((g->scfsi & (0x8 >> k)) == 0) {
+ slen = (k < 2) ? slen1 : slen2;
+ for(i=0;i<n;i++)
+ g->scale_factors[j++] = get_bitsz(&s->gb, slen);
+ } else {
+ /* simply copy from last granule */
+ for(i=0;i<n;i++) {
+ g->scale_factors[j] = sc[j];
+ j++;
+ }
+ }
+ }
+ g->scale_factors[j++] = 0;
+ }
+#ifdef DEBUG
+ {
+ printf("scfsi=%x gr=%d ch=%d scale_factors:\n",
+ g->scfsi, gr, ch);
+ for(i=0;i<j;i++)
+ printf(" %d", g->scale_factors[i]);
+ printf("\n");
+ }
+#endif
+ } else {
+ int tindex, tindex2, slen[4], sl, sf;
+
+ /* LSF scale factors */
+ if (g->block_type == 2) {
+ tindex = g->switch_point ? 2 : 1;
+ } else {
+ tindex = 0;
+ }
+ sf = g->scalefac_compress;
+ if ((s->mode_ext & MODE_EXT_I_STEREO) && ch == 1) {
+ /* intensity stereo case */
+ sf >>= 1;
+ if (sf < 180) {
+ lsf_sf_expand(slen, sf, 6, 6, 0);
+ tindex2 = 3;
+ } else if (sf < 244) {
+ lsf_sf_expand(slen, sf - 180, 4, 4, 0);
+ tindex2 = 4;
+ } else {
+ lsf_sf_expand(slen, sf - 244, 3, 0, 0);
+ tindex2 = 5;
+ }
+ } else {
+ /* normal case */
+ if (sf < 400) {
+ lsf_sf_expand(slen, sf, 5, 4, 4);
+ tindex2 = 0;
+ } else if (sf < 500) {
+ lsf_sf_expand(slen, sf - 400, 5, 4, 0);
+ tindex2 = 1;
+ } else {
+ lsf_sf_expand(slen, sf - 500, 3, 0, 0);
+ tindex2 = 2;
+ g->preflag = 1;
+ }
+ }
+
+ j = 0;
+ for(k=0;k<4;k++) {
+ n = lsf_nsf_table[tindex2][tindex][k];
+ sl = slen[k];
+ for(i=0;i<n;i++)
+ g->scale_factors[j++] = get_bitsz(&s->gb, sl);
+ }
+ /* XXX: should compute exact size */
+ for(;j<40;j++)
+ g->scale_factors[j] = 0;
+#ifdef DEBUG
+ {
+ printf("gr=%d ch=%d scale_factors:\n",
+ gr, ch);
+ for(i=0;i<40;i++)
+ printf(" %d", g->scale_factors[i]);
+ printf("\n");
+ }
+#endif
+ }
+
+ exponents_from_scale_factors(s, g, exponents);
+
+ /* read Huffman coded residue */
+ if (huffman_decode(s, g, exponents,
+ bits_pos + g->part2_3_length) < 0)
+ return -1;
+#if defined(DEBUG) && 0
+ sample_dump(3, g->sb_hybrid, 576);
+#endif
+
+ /* skip extension bits */
+ bits_left = g->part2_3_length - (get_bits_count(&s->gb) - bits_pos);
+ if (bits_left < 0) {
+ dprintf("bits_left=%d\n", bits_left);
+ return -1;
+ }
+ while (bits_left >= 16) {
+ skip_bits(&s->gb, 16);
+ bits_left -= 16;
+ }
+ if (bits_left > 0)
+ skip_bits(&s->gb, bits_left);
+ } /* ch */
+
+ if (s->nb_channels == 2)
+ compute_stereo(s, &granules[0][gr], &granules[1][gr]);
+
+ for(ch=0;ch<s->nb_channels;ch++) {
+ g = &granules[ch][gr];
+
+ reorder_block(s, g);
+#ifdef DEBUG
+ sample_dump(0, g->sb_hybrid, 576);
+#endif
+ compute_antialias(s, g);
+#ifdef DEBUG
+ sample_dump(1, g->sb_hybrid, 576);
+#endif
+ compute_imdct(s, g, &s->sb_samples[ch][18 * gr][0], s->mdct_buf[ch]);
+#ifdef DEBUG
+ sample_dump(2, &s->sb_samples[ch][18 * gr][0], 576);
+#endif
+ }
+ } /* gr */
+ return nb_granules * 18;
+}
+
+static int mp_decode_frame(MPADecodeContext *s,
+ short *samples)
+{
+ int i, nb_frames, ch;
+ short *samples_ptr;
+
+ init_get_bits(&s->gb, s->inbuf + HEADER_SIZE,
+ s->inbuf_ptr - s->inbuf - HEADER_SIZE);
+
+ /* skip error protection field */
+ if (s->error_protection)
+ get_bits(&s->gb, 16);
+
+ dprintf("frame %d:\n", s->frame_count);
+ switch(s->layer) {
+ case 1:
+ nb_frames = mp_decode_layer1(s);
+ break;
+ case 2:
+ nb_frames = mp_decode_layer2(s);
+ break;
+ case 3:
+ default:
+ nb_frames = mp_decode_layer3(s);
+ break;
+ }
+#if defined(DEBUG)
+ for(i=0;i<nb_frames;i++) {
+ for(ch=0;ch<s->nb_channels;ch++) {
+ int j;
+ printf("%d-%d:", i, ch);
+ for(j=0;j<SBLIMIT;j++)
+ printf(" %0.6f", (double)s->sb_samples[ch][i][j] / FRAC_ONE);
+ printf("\n");
+ }
+ }
+#endif
+ /* apply the synthesis filter */
+ for(ch=0;ch<s->nb_channels;ch++) {
+ samples_ptr = samples + ch;
+ for(i=0;i<nb_frames;i++) {
+ synth_filter(s, ch, samples_ptr, s->nb_channels,
+ s->sb_samples[ch][i]);
+ samples_ptr += 32 * s->nb_channels;
+ }
+ }
+#ifdef DEBUG
+ s->frame_count++;
+#endif
+ return nb_frames * 32 * sizeof(short) * s->nb_channels;
+}
+
static int decode_frame(AVCodecContext * avctx,
void *data, int *data_size,
UINT8 * buf, int buf_size)
@@ -237,7 +2252,19 @@ static int decode_frame(AVCodecContext * avctx,
while (buf_size > 0) {
len = s->inbuf_ptr - s->inbuf;
if (s->frame_size == 0) {
- /* no header seen : find one. We need at least 7 bytes to parse it */
+ /* special case for next header for first frame in free
+ format case (XXX: find a simpler method) */
+ if (s->free_format_next_header != 0) {
+ s->inbuf[0] = s->free_format_next_header >> 24;
+ s->inbuf[1] = s->free_format_next_header >> 16;
+ s->inbuf[2] = s->free_format_next_header >> 8;
+ s->inbuf[3] = s->free_format_next_header;
+ s->inbuf_ptr = s->inbuf + 4;
+ s->free_format_next_header = 0;
+ goto got_header;
+ }
+ /* no header seen : find one. We need at least HEADER_SIZE
+ bytes to parse it */
len = HEADER_SIZE - len;
if (len > buf_size)
len = buf_size;
@@ -246,20 +2273,80 @@ static int decode_frame(AVCodecContext * avctx,
s->inbuf_ptr += len;
buf_size -= len;
if ((s->inbuf_ptr - s->inbuf) == HEADER_SIZE) {
+ got_header:
header = (s->inbuf[0] << 24) | (s->inbuf[1] << 16) |
(s->inbuf[2] << 8) | s->inbuf[3];
if (check_header(header) < 0) {
/* no sync found : move by one byte (inefficient, but simple!) */
memcpy(s->inbuf, s->inbuf + 1, HEADER_SIZE - 1);
s->inbuf_ptr--;
+ dprintf("skip %x\n", header);
+ /* reset free format frame size to give a chance
+ to get a new bitrate */
+ s->free_format_frame_size = 0;
} else {
- decode_header(s, header);
- /* update codec info */
- avctx->sample_rate = s->sample_rate;
- avctx->channels = s->mpstr.fr.stereo ? 2 : 1;
- avctx->bit_rate = s->bit_rate;
+ if (decode_header(s, header) == 1) {
+ /* free format: compute frame size */
+ s->frame_size = -1;
+ } else {
+ /* update codec info */
+ avctx->sample_rate = s->sample_rate;
+ avctx->channels = s->nb_channels;
+ avctx->bit_rate = s->bit_rate;
+ }
}
}
+ } else if (s->frame_size == -1) {
+ /* free format : find next sync to compute frame size */
+ len = MPA_MAX_CODED_FRAME_SIZE - len;
+ if (len > buf_size)
+ len = buf_size;
+ if (len == 0) {
+ /* frame too long: resync */
+ s->frame_size = 0;
+ } else {
+ UINT8 *p, *pend;
+ UINT32 header1;
+ int padding;
+
+ memcpy(s->inbuf_ptr, buf_ptr, len);
+ /* check for header */
+ p = s->inbuf_ptr - 3;
+ pend = s->inbuf_ptr + len - 4;
+ while (p <= pend) {
+ header = (p[0] << 24) | (p[1] << 16) |
+ (p[2] << 8) | p[3];
+ header1 = (s->inbuf[0] << 24) | (s->inbuf[1] << 16) |
+ (s->inbuf[2] << 8) | s->inbuf[3];
+ /* check with high probability that we have a
+ valid header */
+ if ((header & SAME_HEADER_MASK) ==
+ (header1 & SAME_HEADER_MASK)) {
+ /* header found: update pointers */
+ len = (p + 4) - s->inbuf_ptr;
+ buf_ptr += len;
+ buf_size -= len;
+ s->inbuf_ptr = p;
+ /* compute frame size */
+ s->free_format_next_header = header;
+ s->free_format_frame_size = s->inbuf_ptr - s->inbuf;
+ padding = (header1 >> 9) & 1;
+ if (s->layer == 1)
+ s->free_format_frame_size -= padding * 4;
+ else
+ s->free_format_frame_size -= padding;
+ dprintf("free frame size=%d padding=%d\n",
+ s->free_format_frame_size, padding);
+ decode_header(s, header1);
+ goto next_data;
+ }
+ p++;
+ }
+ /* not found: simply increase pointers */
+ buf_ptr += len;
+ s->inbuf_ptr += len;
+ buf_size -= len;
+ }
} else if (len < s->frame_size) {
len = s->frame_size - len;
if (len > buf_size)
@@ -276,6 +2363,7 @@ static int decode_frame(AVCodecContext * avctx,
*data_size = out_size;
break;
}
+ next_data:
}
return buf_ptr - buf;
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-20 20:39:10 +0000