/* * Musepack SV7 decoder * Copyright (c) 2006 Konstantin Shishkov * * This file is part of Libav. * * Libav 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. * * Libav 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 Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples * divided into 32 subbands. */ #include "libavutil/channel_layout.h" #include "libavutil/internal.h" #include "libavutil/lfg.h" #include "avcodec.h" #include "get_bits.h" #include "internal.h" #include "mpegaudiodsp.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 const uint16_t quant_offsets[MPC7_QUANT_VLC_TABLES*2 + 1] = { 0, 512, 1024, 1536, 2052, 2564, 3076, 3588, 4100, 4612, 5124, 5636, 6164, 6676, 7224 }; static av_cold int mpc7_decode_init(AVCodecContext * avctx) { int i, j; MPCContext *c = avctx->priv_data; GetBitContext gb; LOCAL_ALIGNED_16(uint8_t, buf, [16]); static int vlc_initialized = 0; static VLC_TYPE scfi_table[1 << MPC7_SCFI_BITS][2]; static VLC_TYPE dscf_table[1 << MPC7_DSCF_BITS][2]; static VLC_TYPE hdr_table[1 << MPC7_HDR_BITS][2]; static VLC_TYPE quant_tables[7224][2]; /* Musepack SV7 is always stereo */ if (avctx->channels != 2) { avpriv_request_sample(avctx, "%d channels", avctx->channels); return AVERROR_PATCHWELCOME; } 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_lfg_init(&c->rnd, 0xDEADBEEF); ff_bswapdsp_init(&c->bdsp); ff_mpadsp_init(&c->mpadsp); c->bdsp.bswap_buf((uint32_t *) buf, (const uint32_t *) 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_long(&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; avctx->sample_fmt = AV_SAMPLE_FMT_S16P; avctx->channel_layout = AV_CH_LAYOUT_STEREO; if(vlc_initialized) return 0; av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n"); scfi_vlc.table = scfi_table; scfi_vlc.table_allocated = 1 << MPC7_SCFI_BITS; if(init_vlc(&scfi_vlc, MPC7_SCFI_BITS, MPC7_SCFI_SIZE, &mpc7_scfi[1], 2, 1, &mpc7_scfi[0], 2, 1, INIT_VLC_USE_NEW_STATIC)){ av_log(avctx, AV_LOG_ERROR, "Cannot init SCFI VLC\n"); return -1; } dscf_vlc.table = dscf_table; dscf_vlc.table_allocated = 1 << MPC7_DSCF_BITS; if(init_vlc(&dscf_vlc, MPC7_DSCF_BITS, MPC7_DSCF_SIZE, &mpc7_dscf[1], 2, 1, &mpc7_dscf[0], 2, 1, INIT_VLC_USE_NEW_STATIC)){ av_log(avctx, AV_LOG_ERROR, "Cannot init DSCF VLC\n"); return -1; } hdr_vlc.table = hdr_table; hdr_vlc.table_allocated = 1 << MPC7_HDR_BITS; if(init_vlc(&hdr_vlc, MPC7_HDR_BITS, MPC7_HDR_SIZE, &mpc7_hdr[1], 2, 1, &mpc7_hdr[0], 2, 1, INIT_VLC_USE_NEW_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++){ quant_vlc[i][j].table = &quant_tables[quant_offsets[i*2 + j]]; quant_vlc[i][j].table_allocated = quant_offsets[i*2 + j + 1] - quant_offsets[i*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_NEW_STATIC)){ av_log(avctx, AV_LOG_ERROR, "Cannot init QUANT VLC %i,%i\n",i,j); return -1; } } } vlc_initialized = 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_lfg_get(&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 get_scale_idx(GetBitContext *gb, int ref) { int t = get_vlc2(gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7; if (t == 8) return get_bits(gb, 6); return av_clip_uintp2(ref + t, 7); } static int mpc7_decode_frame(AVCodecContext * avctx, void *data, int *got_frame_ptr, AVPacket *avpkt) { AVFrame *frame = data; const uint8_t *buf = avpkt->data; int buf_size; MPCContext *c = avctx->priv_data; GetBitContext gb; int i, ch; int mb = -1; Band *bands = c->bands; int off, ret, last_frame, skip; int bits_used, bits_avail; memset(bands, 0, sizeof(*bands) * (c->maxbands + 1)); buf_size = avpkt->size & ~3; if (buf_size <= 0) { av_log(avctx, AV_LOG_ERROR, "packet size is too small (%i bytes)\n", avpkt->size); return AVERROR_INVALIDDATA; } if (buf_size != avpkt->size) { av_log(avctx, AV_LOG_WARNING, "packet size is not a multiple of 4. " "extra bytes at the end will be skipped.\n"); } skip = buf[0]; last_frame = buf[1]; buf += 4; buf_size -= 4; /* get output buffer */ frame->nb_samples = last_frame ? c->lastframelen : MPC_FRAME_SIZE; if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) { av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); return ret; } av_fast_padded_malloc(&c->bits, &c->buf_size, buf_size); if (!c->bits) return AVERROR(ENOMEM); c->bdsp.bswap_buf((uint32_t *) c->bits, (const uint32_t *) buf, buf_size >> 2); init_get_bits(&gb, c->bits, buf_size * 8); skip_bits_long(&gb, skip); /* read subband indexes */ for(i = 0; i <= c->maxbands; i++){ for(ch = 0; ch < 2; ch++){ int t = 4; if(i) t = get_vlc2(&gb, hdr_vlc.table, MPC7_HDR_BITS, 1) - 5; if(t == 4) bands[i].res[ch] = get_bits(&gb, 4); else bands[i].res[ch] = av_clip(bands[i-1].res[ch] + t, 0, 17); } 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]; bands[i].scf_idx[ch][0] = get_scale_idx(&gb, bands[i].scf_idx[ch][2]); switch(bands[i].scfi[ch]){ case 0: bands[i].scf_idx[ch][1] = get_scale_idx(&gb, bands[i].scf_idx[ch][0]); bands[i].scf_idx[ch][2] = get_scale_idx(&gb, bands[i].scf_idx[ch][1]); break; case 1: bands[i].scf_idx[ch][1] = get_scale_idx(&gb, bands[i].scf_idx[ch][0]); 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]; bands[i].scf_idx[ch][2] = get_scale_idx(&gb, bands[i].scf_idx[ch][1]); 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, (int16_t **)frame->extended_data, 2); bits_used = get_bits_count(&gb); bits_avail = buf_size * 8; if (!last_frame && ((bits_avail < bits_used) || (bits_used + 32 <= bits_avail))) { av_log(avctx, AV_LOG_ERROR, "Error decoding frame: used %i of %i bits\n", bits_used, bits_avail); return -1; } if(c->frames_to_skip){ c->frames_to_skip--; *got_frame_ptr = 0; return avpkt->size; } *got_frame_ptr = 1; return avpkt->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; } static av_cold int mpc7_decode_close(AVCodecContext *avctx) { MPCContext *c = avctx->priv_data; av_freep(&c->bits); c->buf_size = 0; return 0; } AVCodec ff_mpc7_decoder = { .name = "mpc7", .long_name = NULL_IF_CONFIG_SMALL("Musepack SV7"), .type = AVMEDIA_TYPE_AUDIO, .id = AV_CODEC_ID_MUSEPACK7, .priv_data_size = sizeof(MPCContext), .init = mpc7_decode_init, .close = mpc7_decode_close, .decode = mpc7_decode_frame, .flush = mpc7_decode_flush, .capabilities = AV_CODEC_CAP_DR1, .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P, AV_SAMPLE_FMT_NONE }, };