yading@10: /* yading@10: * Real Audio 1.0 (14.4K) yading@10: * yading@10: * Copyright (c) 2008 Vitor Sessak yading@10: * Copyright (c) 2003 Nick Kurshev yading@10: * Based on public domain decoder at http://www.honeypot.net/audio yading@10: * yading@10: * This file is part of FFmpeg. yading@10: * yading@10: * FFmpeg is free software; you can redistribute it and/or yading@10: * modify it under the terms of the GNU Lesser General Public yading@10: * License as published by the Free Software Foundation; either yading@10: * version 2.1 of the License, or (at your option) any later version. yading@10: * yading@10: * FFmpeg is distributed in the hope that it will be useful, yading@10: * but WITHOUT ANY WARRANTY; without even the implied warranty of yading@10: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU yading@10: * Lesser General Public License for more details. yading@10: * yading@10: * You should have received a copy of the GNU Lesser General Public yading@10: * License along with FFmpeg; if not, write to the Free Software yading@10: * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA yading@10: */ yading@10: yading@10: #include "libavutil/channel_layout.h" yading@10: #include "avcodec.h" yading@10: #include "get_bits.h" yading@10: #include "internal.h" yading@10: #include "ra144.h" yading@10: yading@10: yading@10: static av_cold int ra144_decode_init(AVCodecContext * avctx) yading@10: { yading@10: RA144Context *ractx = avctx->priv_data; yading@10: yading@10: ractx->avctx = avctx; yading@10: yading@10: ractx->lpc_coef[0] = ractx->lpc_tables[0]; yading@10: ractx->lpc_coef[1] = ractx->lpc_tables[1]; yading@10: yading@10: avctx->channels = 1; yading@10: avctx->channel_layout = AV_CH_LAYOUT_MONO; yading@10: avctx->sample_fmt = AV_SAMPLE_FMT_S16; yading@10: yading@10: return 0; yading@10: } yading@10: yading@10: static void do_output_subblock(RA144Context *ractx, const int16_t *lpc_coefs, yading@10: int gval, GetBitContext *gb) yading@10: { yading@10: int cba_idx = get_bits(gb, 7); // index of the adaptive CB, 0 if none yading@10: int gain = get_bits(gb, 8); yading@10: int cb1_idx = get_bits(gb, 7); yading@10: int cb2_idx = get_bits(gb, 7); yading@10: yading@10: ff_subblock_synthesis(ractx, lpc_coefs, cba_idx, cb1_idx, cb2_idx, gval, yading@10: gain); yading@10: } yading@10: yading@10: /** Uncompress one block (20 bytes -> 160*2 bytes). */ yading@10: static int ra144_decode_frame(AVCodecContext * avctx, void *data, yading@10: int *got_frame_ptr, AVPacket *avpkt) yading@10: { yading@10: AVFrame *frame = data; yading@10: const uint8_t *buf = avpkt->data; yading@10: int buf_size = avpkt->size; yading@10: static const uint8_t sizes[LPC_ORDER] = {6, 5, 5, 4, 4, 3, 3, 3, 3, 2}; yading@10: unsigned int refl_rms[NBLOCKS]; // RMS of the reflection coefficients yading@10: int16_t block_coefs[NBLOCKS][LPC_ORDER]; // LPC coefficients of each sub-block yading@10: unsigned int lpc_refl[LPC_ORDER]; // LPC reflection coefficients of the frame yading@10: int i, j; yading@10: int ret; yading@10: int16_t *samples; yading@10: unsigned int energy; yading@10: yading@10: RA144Context *ractx = avctx->priv_data; yading@10: GetBitContext gb; yading@10: yading@10: if (buf_size < FRAMESIZE) { yading@10: av_log(avctx, AV_LOG_ERROR, yading@10: "Frame too small (%d bytes). Truncated file?\n", buf_size); yading@10: *got_frame_ptr = 0; yading@10: return AVERROR_INVALIDDATA; yading@10: } yading@10: yading@10: /* get output buffer */ yading@10: frame->nb_samples = NBLOCKS * BLOCKSIZE; yading@10: if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) yading@10: return ret; yading@10: samples = (int16_t *)frame->data[0]; yading@10: yading@10: init_get_bits(&gb, buf, FRAMESIZE * 8); yading@10: yading@10: for (i = 0; i < LPC_ORDER; i++) yading@10: lpc_refl[i] = ff_lpc_refl_cb[i][get_bits(&gb, sizes[i])]; yading@10: yading@10: ff_eval_coefs(ractx->lpc_coef[0], lpc_refl); yading@10: ractx->lpc_refl_rms[0] = ff_rms(lpc_refl); yading@10: yading@10: energy = ff_energy_tab[get_bits(&gb, 5)]; yading@10: yading@10: refl_rms[0] = ff_interp(ractx, block_coefs[0], 1, 1, ractx->old_energy); yading@10: refl_rms[1] = ff_interp(ractx, block_coefs[1], 2, yading@10: energy <= ractx->old_energy, yading@10: ff_t_sqrt(energy*ractx->old_energy) >> 12); yading@10: refl_rms[2] = ff_interp(ractx, block_coefs[2], 3, 0, energy); yading@10: refl_rms[3] = ff_rescale_rms(ractx->lpc_refl_rms[0], energy); yading@10: yading@10: ff_int_to_int16(block_coefs[3], ractx->lpc_coef[0]); yading@10: yading@10: for (i=0; i < NBLOCKS; i++) { yading@10: do_output_subblock(ractx, block_coefs[i], refl_rms[i], &gb); yading@10: yading@10: for (j=0; j < BLOCKSIZE; j++) yading@10: *samples++ = av_clip_int16(ractx->curr_sblock[j + 10] << 2); yading@10: } yading@10: yading@10: ractx->old_energy = energy; yading@10: ractx->lpc_refl_rms[1] = ractx->lpc_refl_rms[0]; yading@10: yading@10: FFSWAP(unsigned int *, ractx->lpc_coef[0], ractx->lpc_coef[1]); yading@10: yading@10: *got_frame_ptr = 1; yading@10: yading@10: return FRAMESIZE; yading@10: } yading@10: yading@10: AVCodec ff_ra_144_decoder = { yading@10: .name = "real_144", yading@10: .type = AVMEDIA_TYPE_AUDIO, yading@10: .id = AV_CODEC_ID_RA_144, yading@10: .priv_data_size = sizeof(RA144Context), yading@10: .init = ra144_decode_init, yading@10: .decode = ra144_decode_frame, yading@10: .capabilities = CODEC_CAP_DR1, yading@10: .long_name = NULL_IF_CONFIG_SMALL("RealAudio 1.0 (14.4K)"), yading@10: };