From b8560637d93b632bd6b318baea4dc68b79e2ef85 Mon Sep 17 00:00:00 2001 From: Kostya Shishkov Date: Sat, 17 Mar 2012 08:48:57 +0100 Subject: RealAudio Lossless decoder --- libavcodec/ralf.c | 536 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 536 insertions(+) create mode 100644 libavcodec/ralf.c (limited to 'libavcodec/ralf.c') diff --git a/libavcodec/ralf.c b/libavcodec/ralf.c new file mode 100644 index 0000000000..38e7e69cb7 --- /dev/null +++ b/libavcodec/ralf.c @@ -0,0 +1,536 @@ +/* + * RealAudio Lossless decoder + * + * Copyright (c) 2012 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 + * This is a decoder for Real Audio Lossless format. + * Dedicated to the mastermind behind it, Ralph Wiggum. + */ + +#include "avcodec.h" +#include "get_bits.h" +#include "golomb.h" +#include "unary.h" +#include "libavutil/audioconvert.h" +#include "ralfdata.h" + +#define FILTER_NONE 0 +#define FILTER_RAW 642 + +typedef struct VLCSet { + VLC filter_params; + VLC bias; + VLC coding_mode; + VLC filter_coeffs[10][11]; + VLC short_codes[15]; + VLC long_codes[125]; +} VLCSet; + +#define RALF_MAX_PKT_SIZE 8192 + +typedef struct RALFContext { + AVFrame frame; + + int version; + int max_frame_size; + VLCSet sets[3]; + int32_t channel_data[2][4096]; + + int filter_params; ///< combined filter parameters for the current channel data + int filter_length; ///< length of the filter for the current channel data + int filter_bits; ///< filter precision for the current channel data + int32_t filter[64]; + + int bias[2]; ///< a constant value added to channel data after filtering + + int num_blocks; ///< number of blocks inside the frame + int sample_offset; + int block_size[1 << 12]; ///< size of the blocks + int block_pts[1 << 12]; ///< block start time (in milliseconds) + + uint8_t pkt[16384]; + int has_pkt; +} RALFContext; + +#define MAX_ELEMS 644 // no RALF table uses more than that + +static int init_ralf_vlc(VLC *vlc, const uint8_t *data, int elems) +{ + uint8_t lens[MAX_ELEMS]; + uint16_t codes[MAX_ELEMS]; + int counts[17], prefixes[18]; + int i, cur_len; + int max_bits = 0; + GetBitContext gb; + + init_get_bits(&gb, data, elems * 4); + + for (i = 0; i <= 16; i++) + counts[i] = 0; + for (i = 0; i < elems; i++) { + cur_len = get_bits(&gb, 4) + 1; + counts[cur_len]++; + max_bits = FFMAX(max_bits, cur_len); + lens[i] = cur_len; + } + prefixes[1] = 0; + for (i = 1; i <= 16; i++) + prefixes[i + 1] = (prefixes[i] + counts[i]) << 1; + + for (i = 0; i < elems; i++) + codes[i] = prefixes[lens[i]]++; + + return ff_init_vlc_sparse(vlc, FFMIN(max_bits, 9), elems, + lens, 1, 1, codes, 2, 2, NULL, 0, 0, 0); +} + +static av_cold int decode_close(AVCodecContext *avctx) +{ + RALFContext *ctx = avctx->priv_data; + int i, j, k; + + for (i = 0; i < 3; i++) { + ff_free_vlc(&ctx->sets[i].filter_params); + ff_free_vlc(&ctx->sets[i].bias); + ff_free_vlc(&ctx->sets[i].coding_mode); + for (j = 0; j < 10; j++) + for (k = 0; k < 11; k++) + ff_free_vlc(&ctx->sets[i].filter_coeffs[j][k]); + for (j = 0; j < 15; j++) + ff_free_vlc(&ctx->sets[i].short_codes[j]); + for (j = 0; j < 125; j++) + ff_free_vlc(&ctx->sets[i].long_codes[j]); + } + + return 0; +} + +static av_cold int decode_init(AVCodecContext *avctx) +{ + RALFContext *ctx = avctx->priv_data; + int i, j, k; + int ret; + + if (avctx->extradata_size < 24 || memcmp(avctx->extradata, "LSD:", 4)) { + av_log(avctx, AV_LOG_ERROR, "Extradata is not groovy, dude\n"); + return AVERROR_INVALIDDATA; + } + + ctx->version = AV_RB16(avctx->extradata + 4); + if (ctx->version != 0x103) { + av_log_ask_for_sample(avctx, "unknown version %X\n", ctx->version); + return AVERROR_PATCHWELCOME; + } + + avctx->channels = AV_RB16(avctx->extradata + 8); + avctx->sample_rate = AV_RB32(avctx->extradata + 12); + if (avctx->channels < 1 || avctx->channels > 2 + || avctx->sample_rate < 8000 || avctx->sample_rate > 96000) { + av_log(avctx, AV_LOG_ERROR, "Invalid coding parameters %d Hz %d ch\n", + avctx->sample_rate, avctx->channels); + return AVERROR_INVALIDDATA; + } + avctx->sample_fmt = AV_SAMPLE_FMT_S16; + avctx->channel_layout = (avctx->channels == 2) ? AV_CH_LAYOUT_STEREO + : AV_CH_LAYOUT_MONO; + + avcodec_get_frame_defaults(&ctx->frame); + avctx->coded_frame = &ctx->frame; + + ctx->max_frame_size = AV_RB32(avctx->extradata + 16); + if (ctx->max_frame_size > (1 << 20) || !ctx->max_frame_size) { + av_log(avctx, AV_LOG_ERROR, "invalid frame size %d\n", + ctx->max_frame_size); + } + ctx->max_frame_size = FFMAX(ctx->max_frame_size, avctx->sample_rate); + + for (i = 0; i < 3; i++) { + ret = init_ralf_vlc(&ctx->sets[i].filter_params, filter_param_def[i], + FILTERPARAM_ELEMENTS); + if (ret < 0) { + decode_close(avctx); + return ret; + } + ret = init_ralf_vlc(&ctx->sets[i].bias, bias_def[i], BIAS_ELEMENTS); + if (ret < 0) { + decode_close(avctx); + return ret; + } + ret = init_ralf_vlc(&ctx->sets[i].coding_mode, coding_mode_def[i], + CODING_MODE_ELEMENTS); + if (ret < 0) { + decode_close(avctx); + return ret; + } + for (j = 0; j < 10; j++) { + for (k = 0; k < 11; k++) { + ret = init_ralf_vlc(&ctx->sets[i].filter_coeffs[j][k], + filter_coeffs_def[i][j][k], + FILTER_COEFFS_ELEMENTS); + if (ret < 0) { + decode_close(avctx); + return ret; + } + } + } + for (j = 0; j < 15; j++) { + ret = init_ralf_vlc(&ctx->sets[i].short_codes[j], + short_codes_def[i][j], SHORT_CODES_ELEMENTS); + if (ret < 0) { + decode_close(avctx); + return ret; + } + } + for (j = 0; j < 125; j++) { + ret = init_ralf_vlc(&ctx->sets[i].long_codes[j], + long_codes_def[i][j], LONG_CODES_ELEMENTS); + if (ret < 0) { + decode_close(avctx); + return ret; + } + } + } + + return 0; +} + +static inline int extend_code(GetBitContext *gb, int val, int range, int bits) +{ + if (val == 0) { + val = -range - get_ue_golomb(gb); + } else if (val == range * 2) { + val = range + get_ue_golomb(gb); + } else { + val -= range; + } + if (bits) + val = (val << bits) | get_bits(gb, bits); + return val; +} + +static int decode_channel(RALFContext *ctx, GetBitContext *gb, int ch, + int length, int mode, int bits) +{ + int i, t; + int code_params; + VLCSet *set = ctx->sets + mode; + VLC *code_vlc; int range, range2, add_bits; + int *dst = ctx->channel_data[ch]; + + ctx->filter_params = get_vlc2(gb, set->filter_params.table, 9, 2); + ctx->filter_bits = (ctx->filter_params - 2) >> 6; + ctx->filter_length = ctx->filter_params - (ctx->filter_bits << 6) - 1; + + if (ctx->filter_params == FILTER_RAW) { + for (i = 0; i < length; i++) + dst[i] = get_bits(gb, bits); + ctx->bias[ch] = 0; + return 0; + } + + ctx->bias[ch] = get_vlc2(gb, set->bias.table, 9, 2); + ctx->bias[ch] = extend_code(gb, ctx->bias[ch], 127, 4); + + if (ctx->filter_params == FILTER_NONE) { + memset(dst, 0, sizeof(*dst) * length); + return 0; + } + + if (ctx->filter_params > 1) { + int cmode = 0, coeff = 0; + VLC *vlc = set->filter_coeffs[ctx->filter_bits] + 5; + + add_bits = ctx->filter_bits; + + for (i = 0; i < ctx->filter_length; i++) { + t = get_vlc2(gb, vlc[cmode].table, vlc[cmode].bits, 2); + t = extend_code(gb, t, 21, add_bits); + if (!cmode) + coeff -= 12 << add_bits; + coeff = t - coeff; + ctx->filter[i] = coeff; + + cmode = coeff >> add_bits; + if (cmode < 0) { + cmode = -1 - av_log2(-cmode); + if (cmode < -5) + cmode = -5; + } else if (cmode > 0) { + cmode = 1 + av_log2(cmode); + if (cmode > 5) + cmode = 5; + } + } + } + + code_params = get_vlc2(gb, set->coding_mode.table, set->coding_mode.bits, 2); + if (code_params >= 15) { + add_bits = av_clip((code_params / 5 - 3) / 2, 0, 10); + if (add_bits > 9 && (code_params % 5) != 2) + add_bits--; + range = 10; + range2 = 21; + code_vlc = set->long_codes + code_params - 15; + } else { + add_bits = 0; + range = 6; + range2 = 13; + code_vlc = set->short_codes + code_params; + } + + for (i = 0; i < length; i += 2) { + int code1, code2; + + t = get_vlc2(gb, code_vlc->table, code_vlc->bits, 2); + code1 = t / range2; + code2 = t % range2; + dst[i] = extend_code(gb, code1, range, 0) << add_bits; + dst[i + 1] = extend_code(gb, code2, range, 0) << add_bits; + if (add_bits) { + dst[i] |= get_bits(gb, add_bits); + dst[i + 1] |= get_bits(gb, add_bits); + } + } + + return 0; +} + +static void apply_lpc(RALFContext *ctx, int ch, int length, int bits) +{ + int i, j, acc; + int *audio = ctx->channel_data[ch]; + int bias = 1 << (ctx->filter_bits - 1); + int max_clip = (1 << bits) - 1, min_clip = -max_clip - 1; + + for (i = 1; i < length; i++) { + int flen = FFMIN(ctx->filter_length, i); + + acc = 0; + for (j = 0; j < flen; j++) + acc += ctx->filter[j] * audio[i - j - 1]; + if (acc < 0) { + acc = (acc + bias - 1) >> ctx->filter_bits; + acc = FFMAX(acc, min_clip); + } else { + acc = (acc + bias) >> ctx->filter_bits; + acc = FFMIN(acc, max_clip); + } + audio[i] += acc; + } +} + +static int decode_block(AVCodecContext *avctx, GetBitContext *gb, int16_t *dst) +{ + RALFContext *ctx = avctx->priv_data; + int len, ch, ret; + int dmode, mode[2], bits[2]; + int *ch0, *ch1; + int i, t, t2; + + len = 12 - get_unary(gb, 0, 6); + + if (len <= 7) len ^= 1; // codes for length = 6 and 7 are swapped + len = 1 << len; + + if (ctx->sample_offset + len > ctx->max_frame_size) { + av_log(avctx, AV_LOG_ERROR, + "Decoder's stomach is crying, it ate too many samples\n"); + return AVERROR_INVALIDDATA; + } + + if (avctx->channels > 1) + dmode = get_bits(gb, 2) + 1; + else + dmode = 0; + + mode[0] = (dmode == 4) ? 1 : 0; + mode[1] = (dmode >= 2) ? 2 : 0; + bits[0] = 16; + bits[1] = (mode[1] == 2) ? 17 : 16; + + for (ch = 0; ch < avctx->channels; ch++) { + if ((ret = decode_channel(ctx, gb, ch, len, mode[ch], bits[ch])) < 0) + return ret; + if (ctx->filter_params > 1 && ctx->filter_params != FILTER_RAW) { + ctx->filter_bits += 3; + apply_lpc(ctx, ch, len, bits[ch]); + } + if (get_bits_left(gb) < 0) + return AVERROR_INVALIDDATA; + } + ch0 = ctx->channel_data[0]; + ch1 = ctx->channel_data[1]; + switch (dmode) { + case 0: + for (i = 0; i < len; i++) + *dst++ = ch0[i] + ctx->bias[0]; + break; + case 1: + for (i = 0; i < len; i++) { + *dst++ = ch0[i] + ctx->bias[0]; + *dst++ = ch1[i] + ctx->bias[1]; + } + break; + case 2: + for (i = 0; i < len; i++) { + ch0[i] += ctx->bias[0]; + *dst++ = ch0[i]; + *dst++ = ch0[i] - (ch1[i] + ctx->bias[1]); + } + break; + case 3: + for (i = 0; i < len; i++) { + t = ch0[i] + ctx->bias[0]; + t2 = ch1[i] + ctx->bias[1]; + *dst++ = t + t2; + *dst++ = t; + } + break; + case 4: + for (i = 0; i < len; i++) { + t = ch1[i] + ctx->bias[1]; + t2 = ((ch0[i] + ctx->bias[0]) << 1) | (t & 1); + *dst++ = (t2 + t) / 2; + *dst++ = (t2 - t) / 2; + } + break; + } + + ctx->sample_offset += len; + + return 0; +} + +static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, + AVPacket *avpkt) +{ + RALFContext *ctx = avctx->priv_data; + int16_t *samples; + int ret; + GetBitContext gb; + int table_size, table_bytes, i; + const uint8_t *src, *block_pointer; + int src_size; + int bytes_left; + + if (ctx->has_pkt) { + ctx->has_pkt = 0; + table_bytes = (AV_RB16(avpkt->data) + 7) >> 3; + if (table_bytes + 3 > avpkt->size || avpkt->size > RALF_MAX_PKT_SIZE) { + av_log(avctx, AV_LOG_ERROR, "Wrong packet's breath smells of wrong data!\n"); + return AVERROR_INVALIDDATA; + } + if (memcmp(ctx->pkt, avpkt->data, 2 + table_bytes)) { + av_log(avctx, AV_LOG_ERROR, "Wrong packet tails are wrong!\n"); + return AVERROR_INVALIDDATA; + } + + src = ctx->pkt; + src_size = RALF_MAX_PKT_SIZE + avpkt->size; + memcpy(ctx->pkt + RALF_MAX_PKT_SIZE, avpkt->data + 2 + table_bytes, + avpkt->size - 2 - table_bytes); + } else { + if (avpkt->size == RALF_MAX_PKT_SIZE) { + memcpy(ctx->pkt, avpkt->data, avpkt->size); + ctx->has_pkt = 1; + *got_frame_ptr = 0; + + return avpkt->size; + } + src = avpkt->data; + src_size = avpkt->size; + } + + ctx->frame.nb_samples = ctx->max_frame_size; + if ((ret = avctx->get_buffer(avctx, &ctx->frame)) < 0) { + av_log(avctx, AV_LOG_ERROR, "Me fail get_buffer()? That's unpossible!\n"); + return ret; + } + samples = (int16_t*)ctx->frame.data[0]; + + if (src_size < 5) { + av_log(avctx, AV_LOG_ERROR, "too short packets are too short!\n"); + return AVERROR_INVALIDDATA; + } + table_size = AV_RB16(src); + table_bytes = (table_size + 7) >> 3; + if (src_size < table_bytes + 3) { + av_log(avctx, AV_LOG_ERROR, "short packets are short!\n"); + return AVERROR_INVALIDDATA; + } + init_get_bits(&gb, src + 2, table_size); + ctx->num_blocks = 0; + while (get_bits_left(&gb) > 0) { + ctx->block_size[ctx->num_blocks] = get_bits(&gb, 15); + if (get_bits1(&gb)) { + ctx->block_pts[ctx->num_blocks] = get_bits(&gb, 9); + } else { + ctx->block_pts[ctx->num_blocks] = 0; + } + ctx->num_blocks++; + } + + block_pointer = src + table_bytes + 2; + bytes_left = src_size - table_bytes - 2; + ctx->sample_offset = 0; + for (i = 0; i < ctx->num_blocks; i++) { + if (bytes_left < ctx->block_size[i]) { + av_log(avctx, AV_LOG_ERROR, "I'm pedaling backwards\n"); + break; + } + init_get_bits(&gb, block_pointer, ctx->block_size[i] * 8); + if (decode_block(avctx, &gb, samples + ctx->sample_offset + * avctx->channels) < 0) { + av_log(avctx, AV_LOG_ERROR, "Sir, I got carsick in your office. Not decoding the rest of packet.\n"); + break; + } + block_pointer += ctx->block_size[i]; + bytes_left -= ctx->block_size[i]; + } + + ctx->frame.nb_samples = ctx->sample_offset; + *got_frame_ptr = ctx->sample_offset > 0; + *(AVFrame*)data = ctx->frame; + + return avpkt->size; +} + +static void decode_flush(AVCodecContext *avctx) +{ + RALFContext *ctx = avctx->priv_data; + + ctx->has_pkt = 0; +} + + +AVCodec ff_ralf_decoder = { + .name = "ralf", + .type = AVMEDIA_TYPE_AUDIO, + .id = CODEC_ID_RALF, + .priv_data_size = sizeof(RALFContext), + .init = decode_init, + .close = decode_close, + .decode = decode_frame, + .flush = decode_flush, + .capabilities = CODEC_CAP_DR1, + .long_name = NULL_IF_CONFIG_SMALL("RealAudio Lossless") +}; -- cgit v1.2.3