Split Musepack decoder into SV7 decoder and synth core

(for upcoming SV8 decoder)

Originally committed as revision 10905 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 14 insertions, 259 deletions

diff --git a/libavcodec/mpc.c b/libavcodec/mpc.c
index 25d0e2ee7f..96e1a20b0c 100644
--- a/libavcodec/mpc.c
+++ b/libavcodec/mpc.c
@@ -1,5 +1,5 @@
 /*
- * Musepack decoder
+ * Musepack decoder core
  * Copyright (c) 2006 Konstantin Shishkov
  *
  * This file is part of FFmpeg.
@@ -20,7 +20,7 @@
  */
 
 /**
- * @file mpc.c Musepack decoder
+ * @file mpc.c Musepack decoder core
  * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
  * divided into 32 subbands.
  */
@@ -35,108 +35,18 @@
 #endif
 #include "mpegaudio.h"
 
+#include "mpc.h"
 #include "mpcdata.h"
 
-#define BANDS            32
-#define SAMPLES_PER_BAND 36
-#define MPC_FRAME_SIZE   (BANDS * SAMPLES_PER_BAND)
-
-static VLC scfi_vlc, dscf_vlc, hdr_vlc, quant_vlc[MPC7_QUANT_VLC_TABLES][2];
-
 static DECLARE_ALIGNED_16(MPA_INT, mpa_window[512]);
 
-typedef struct {
-    DSPContext dsp;
-    int IS, MSS, gapless;
-    int lastframelen, bands;
-    int oldDSCF[2][BANDS];
-    AVRandomState rnd;
-    int frames_to_skip;
-    /* for synthesis */
-    DECLARE_ALIGNED_16(MPA_INT, synth_buf[MPA_MAX_CHANNELS][512*2]);
-    int synth_buf_offset[MPA_MAX_CHANNELS];
-    DECLARE_ALIGNED_16(int32_t, sb_samples[MPA_MAX_CHANNELS][36][SBLIMIT]);
-} MPCContext;
-
-/** Subband structure - hold all variables for each subband */
-typedef struct {
-    int msf; ///< mid-stereo flag
-    int res[2];
-    int scfi[2];
-    int scf_idx[2][3];
-    int Q[2];
-}Band;
-
-static int mpc7_decode_init(AVCodecContext * avctx)
+void ff_mpc_init()
 {
-    int i, j;
-    MPCContext *c = avctx->priv_data;
-    GetBitContext gb;
-    uint8_t buf[16];
-    static int vlc_inited = 0;
-
-    if(avctx->extradata_size < 16){
-        av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
-        return -1;
-    }
-    memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
-    av_init_random(0xDEADBEEF, &c->rnd);
-    dsputil_init(&c->dsp, avctx);
-    c->dsp.bswap_buf(buf, avctx->extradata, 4);
     ff_mpa_synth_init(mpa_window);
-    init_get_bits(&gb, buf, 128);
-
-    c->IS = get_bits1(&gb);
-    c->MSS = get_bits1(&gb);
-    c->bands = get_bits(&gb, 6);
-    if(c->bands >= BANDS){
-        av_log(avctx, AV_LOG_ERROR, "Too many bands: %i\n", c->bands);
-        return -1;
-    }
-    skip_bits(&gb, 88);
-    c->gapless = get_bits1(&gb);
-    c->lastframelen = get_bits(&gb, 11);
-    av_log(avctx, AV_LOG_DEBUG, "IS: %d, MSS: %d, TG: %d, LFL: %d, bands: %d\n",
-            c->IS, c->MSS, c->gapless, c->lastframelen, c->bands);
-    c->frames_to_skip = 0;
-
-    if(vlc_inited) return 0;
-    av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
-    if(init_vlc(&scfi_vlc, MPC7_SCFI_BITS, MPC7_SCFI_SIZE,
-                &mpc7_scfi[1], 2, 1,
-                &mpc7_scfi[0], 2, 1, INIT_VLC_USE_STATIC)){
-        av_log(avctx, AV_LOG_ERROR, "Cannot init SCFI VLC\n");
-        return -1;
-    }
-    if(init_vlc(&dscf_vlc, MPC7_DSCF_BITS, MPC7_DSCF_SIZE,
-                &mpc7_dscf[1], 2, 1,
-                &mpc7_dscf[0], 2, 1, INIT_VLC_USE_STATIC)){
-        av_log(avctx, AV_LOG_ERROR, "Cannot init DSCF VLC\n");
-        return -1;
-    }
-    if(init_vlc(&hdr_vlc, MPC7_HDR_BITS, MPC7_HDR_SIZE,
-                &mpc7_hdr[1], 2, 1,
-                &mpc7_hdr[0], 2, 1, INIT_VLC_USE_STATIC)){
-        av_log(avctx, AV_LOG_ERROR, "Cannot init HDR VLC\n");
-        return -1;
-    }
-    for(i = 0; i < MPC7_QUANT_VLC_TABLES; i++){
-        for(j = 0; j < 2; j++){
-            if(init_vlc(&quant_vlc[i][j], 9, mpc7_quant_vlc_sizes[i],
-                        &mpc7_quant_vlc[i][j][1], 4, 2,
-                        &mpc7_quant_vlc[i][j][0], 4, 2, INIT_VLC_USE_STATIC)){
-                av_log(avctx, AV_LOG_ERROR, "Cannot init QUANT VLC %i,%i\n",i,j);
-                return -1;
-            }
-        }
-    }
-    vlc_inited = 1;
-    return 0;
 }
 
 /**
  * Process decoded Musepack data and produce PCM
- * @todo make it available for MPC8 and MPC6
  */
 static void mpc_synth(MPCContext *c, int16_t *out)
 {
@@ -158,147 +68,29 @@ static void mpc_synth(MPCContext *c, int16_t *out)
         *out++=samples[i];
 }
 
-/**
- * Fill samples for given subband
- */
-static inline void idx_to_quant(MPCContext *c, GetBitContext *gb, int idx, int *dst)
-{
-    int i, i1, t;
-    switch(idx){
-    case -1:
-        for(i = 0; i < SAMPLES_PER_BAND; i++){
-            *dst++ = (av_random(&c->rnd) & 0x3FC) - 510;
-        }
-        break;
-    case 1:
-        i1 = get_bits1(gb);
-        for(i = 0; i < SAMPLES_PER_BAND/3; i++){
-            t = get_vlc2(gb, quant_vlc[0][i1].table, 9, 2);
-            *dst++ = mpc_idx30[t];
-            *dst++ = mpc_idx31[t];
-            *dst++ = mpc_idx32[t];
-        }
-        break;
-    case 2:
-        i1 = get_bits1(gb);
-        for(i = 0; i < SAMPLES_PER_BAND/2; i++){
-            t = get_vlc2(gb, quant_vlc[1][i1].table, 9, 2);
-            *dst++ = mpc_idx50[t];
-            *dst++ = mpc_idx51[t];
-        }
-        break;
-    case  3: case  4: case  5: case  6: case  7:
-        i1 = get_bits1(gb);
-        for(i = 0; i < SAMPLES_PER_BAND; i++)
-            *dst++ = get_vlc2(gb, quant_vlc[idx-1][i1].table, 9, 2) - mpc7_quant_vlc_off[idx-1];
-        break;
-    case  8: case  9: case 10: case 11: case 12:
-    case 13: case 14: case 15: case 16: case 17:
-        t = (1 << (idx - 2)) - 1;
-        for(i = 0; i < SAMPLES_PER_BAND; i++)
-            *dst++ = get_bits(gb, idx - 1) - t;
-        break;
-    default: // case 0 and -2..-17
-        return;
-    }
-}
-
-static int mpc7_decode_frame(AVCodecContext * avctx,
-                            void *data, int *data_size,
-                            uint8_t * buf, int buf_size)
+void ff_mpc_dequantize_and_synth(MPCContext * c, int maxband, void *data)
 {
-    MPCContext *c = avctx->priv_data;
-    GetBitContext gb;
-    uint8_t *bits;
-    int i, j, ch, t;
-    int mb = -1;
-    Band bands[BANDS];
-    int Q[2][MPC_FRAME_SIZE];
+    int i, j, ch;
+    Band *bands = c->bands;
     int off;
     float mul;
-    int bits_used, bits_avail;
 
-    memset(bands, 0, sizeof(bands));
-    if(buf_size <= 4){
-        av_log(avctx, AV_LOG_ERROR, "Too small buffer passed (%i bytes)\n", buf_size);
-    }
-
-    bits = av_malloc(((buf_size - 1) & ~3) + FF_INPUT_BUFFER_PADDING_SIZE);
-    c->dsp.bswap_buf(bits, buf + 4, (buf_size - 4) >> 2);
-    init_get_bits(&gb, bits, (buf_size - 4)* 8);
-    skip_bits(&gb, buf[0]);
-
-    /* read subband indexes */
-    for(i = 0; i <= c->bands; i++){
-        for(ch = 0; ch < 2; ch++){
-            if(i) t = get_vlc2(&gb, hdr_vlc.table, MPC7_HDR_BITS, 1) - 5;
-            if(!i || (t == 4)) bands[i].res[ch] = get_bits(&gb, 4);
-            else bands[i].res[ch] = bands[i-1].res[ch] + t;
-        }
-
-        if(bands[i].res[0] || bands[i].res[1]){
-            mb = i;
-            if(c->MSS) bands[i].msf = get_bits1(&gb);
-        }
-    }
-    /* get scale indexes coding method */
-    for(i = 0; i <= mb; i++)
-        for(ch = 0; ch < 2; ch++)
-            if(bands[i].res[ch]) bands[i].scfi[ch] = get_vlc2(&gb, scfi_vlc.table, MPC7_SCFI_BITS, 1);
-    /* get scale indexes */
-    for(i = 0; i <= mb; i++){
-        for(ch = 0; ch < 2; ch++){
-            if(bands[i].res[ch]){
-                bands[i].scf_idx[ch][2] = c->oldDSCF[ch][i];
-                t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
-                bands[i].scf_idx[ch][0] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][2] + t);
-                switch(bands[i].scfi[ch]){
-                case 0:
-                    t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
-                    bands[i].scf_idx[ch][1] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][0] + t);
-                    t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
-                    bands[i].scf_idx[ch][2] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][1] + t);
-                    break;
-                case 1:
-                    t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
-                    bands[i].scf_idx[ch][1] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][0] + t);
-                    bands[i].scf_idx[ch][2] = bands[i].scf_idx[ch][1];
-                    break;
-                case 2:
-                    bands[i].scf_idx[ch][1] = bands[i].scf_idx[ch][0];
-                    t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
-                    bands[i].scf_idx[ch][2] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][1] + t);
-                    break;
-                case 3:
-                    bands[i].scf_idx[ch][2] = bands[i].scf_idx[ch][1] = bands[i].scf_idx[ch][0];
-                    break;
-                }
-                c->oldDSCF[ch][i] = bands[i].scf_idx[ch][2];
-            }
-        }
-    }
-    /* get quantizers */
-    memset(Q, 0, sizeof(Q));
-    off = 0;
-    for(i = 0; i < BANDS; i++, off += SAMPLES_PER_BAND)
-        for(ch = 0; ch < 2; ch++)
-            idx_to_quant(c, &gb, bands[i].res[ch], Q[ch] + off);
     /* dequantize */
     memset(c->sb_samples, 0, sizeof(c->sb_samples));
     off = 0;
-    for(i = 0; i <= mb; i++, off += SAMPLES_PER_BAND){
+    for(i = 0; i <= maxband; i++, off += SAMPLES_PER_BAND){
         for(ch = 0; ch < 2; ch++){
             if(bands[i].res[ch]){
                 j = 0;
-                mul = mpc_CC[bands[i].res[ch]] * mpc7_SCF[bands[i].scf_idx[ch][0]];
+                mul = mpc_CC[bands[i].res[ch]] * mpc_SCF[bands[i].scf_idx[ch][0]];
                 for(; j < 12; j++)
-                    c->sb_samples[ch][j][i] = mul * Q[ch][j + off];
-                mul = mpc_CC[bands[i].res[ch]] * mpc7_SCF[bands[i].scf_idx[ch][1]];
+                    c->sb_samples[ch][j][i] = mul * c->Q[ch][j + off];
+                mul = mpc_CC[bands[i].res[ch]] * mpc_SCF[bands[i].scf_idx[ch][1]];
                 for(; j < 24; j++)
-                    c->sb_samples[ch][j][i] = mul * Q[ch][j + off];
-                mul = mpc_CC[bands[i].res[ch]] * mpc7_SCF[bands[i].scf_idx[ch][2]];
+                    c->sb_samples[ch][j][i] = mul * c->Q[ch][j + off];
+                mul = mpc_CC[bands[i].res[ch]] * mpc_SCF[bands[i].scf_idx[ch][2]];
                 for(; j < 36; j++)
-                    c->sb_samples[ch][j][i] = mul * Q[ch][j + off];
+                    c->sb_samples[ch][j][i] = mul * c->Q[ch][j + off];
             }
         }
         if(bands[i].msf){
@@ -313,41 +105,4 @@ static int mpc7_decode_frame(AVCodecContext * avctx,
     }
 
     mpc_synth(c, data);
-
-    av_free(bits);
-
-    bits_used = get_bits_count(&gb);
-    bits_avail = (buf_size - 4) * 8;
-    if(!buf[1] && ((bits_avail < bits_used) || (bits_used + 32 <= bits_avail))){
-        av_log(NULL,0, "Error decoding frame: used %i of %i bits\n", bits_used, bits_avail);
-        return -1;
-    }
-    if(c->frames_to_skip){
-        c->frames_to_skip--;
-        *data_size = 0;
-        return buf_size;
-    }
-    *data_size = (buf[1] ? c->lastframelen : MPC_FRAME_SIZE) * 4;
-
-    return buf_size;
-}
-
-static void mpc7_decode_flush(AVCodecContext *avctx)
-{
-    MPCContext *c = avctx->priv_data;
-
-    memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
-    c->frames_to_skip = 32;
 }
-
-AVCodec mpc7_decoder = {
-    "mpc sv7",
-    CODEC_TYPE_AUDIO,
-    CODEC_ID_MUSEPACK7,
-    sizeof(MPCContext),
-    mpc7_decode_init,
-    NULL,
-    NULL,
-    mpc7_decode_frame,
-    .flush = mpc7_decode_flush,
-};