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, 276 insertions, 0 deletions

diff --git a/libavcodec/mpc7.c b/libavcodec/mpc7.c
new file mode 100644
index 0000000000..1632dfc2af
--- /dev/null
+++ b/libavcodec/mpc7.c
@@ -0,0 +1,276 @@
+/*
+ * Musepack SV7 decoder
+ * Copyright (c) 2006 Konstantin Shishkov
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file mpc7.c Musepack SV7 decoder
+ * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
+ * divided into 32 subbands.
+ */
+
+#include "avcodec.h"
+#include "bitstream.h"
+#include "dsputil.h"
+#include "random.h"
+
+#ifdef CONFIG_MPEGAUDIO_HP
+#define USE_HIGHPRECISION
+#endif
+#include "mpegaudio.h"
+
+#include "mpc.h"
+#include "mpc7data.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 int mpc7_decode_init(AVCodecContext * avctx)
+{
+    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_mpc_init();
+    init_get_bits(&gb, buf, 128);
+
+    c->IS = get_bits1(&gb);
+    c->MSS = get_bits1(&gb);
+    c->maxbands = get_bits(&gb, 6);
+    if(c->maxbands >= BANDS){
+        av_log(avctx, AV_LOG_ERROR, "Too many bands: %i\n", c->maxbands);
+        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->maxbands);
+    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;
+}
+
+/**
+ * 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++ = mpc7_idx30[t];
+            *dst++ = mpc7_idx31[t];
+            *dst++ = mpc7_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++ = mpc7_idx50[t];
+            *dst++ = mpc7_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)
+{
+    MPCContext *c = avctx->priv_data;
+    GetBitContext gb;
+    uint8_t *bits;
+    int i, ch, t;
+    int mb = -1;
+    Band *bands = c->bands;
+    int off;
+    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->maxbands; 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(c->Q, 0, sizeof(c->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], c->Q[ch] + off);
+
+    ff_mpc_dequantize_and_synth(c, mb, 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,
+};