0,0 → 1,536 |
/* |
* RealAudio Lossless decoder |
* |
* Copyright (c) 2012 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 |
* This is a decoder for Real Audio Lossless format. |
* Dedicated to the mastermind behind it, Ralph Wiggum. |
*/ |
|
#include "libavutil/attributes.h" |
#include "libavutil/channel_layout.h" |
#include "avcodec.h" |
#include "get_bits.h" |
#include "golomb.h" |
#include "internal.h" |
#include "unary.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 { |
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 av_cold 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; |
int nb = 0; |
|
for (i = 0; i <= 16; i++) |
counts[i] = 0; |
for (i = 0; i < elems; i++) { |
cur_len = (nb ? *data & 0xF : *data >> 4) + 1; |
counts[cur_len]++; |
max_bits = FFMAX(max_bits, cur_len); |
lens[i] = cur_len; |
data += nb; |
nb ^= 1; |
} |
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) { |
avpriv_request_sample(avctx, "Unknown version %X", 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_S16P; |
avctx->channel_layout = (avctx->channels == 2) ? AV_CH_LAYOUT_STEREO |
: AV_CH_LAYOUT_MONO; |
|
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 *dst0, int16_t *dst1) |
{ |
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++) |
dst0[i] = ch0[i] + ctx->bias[0]; |
break; |
case 1: |
for (i = 0; i < len; i++) { |
dst0[i] = ch0[i] + ctx->bias[0]; |
dst1[i] = ch1[i] + ctx->bias[1]; |
} |
break; |
case 2: |
for (i = 0; i < len; i++) { |
ch0[i] += ctx->bias[0]; |
dst0[i] = ch0[i]; |
dst1[i] = 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]; |
dst0[i] = t + t2; |
dst1[i] = 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); |
dst0[i] = (t2 + t) / 2; |
dst1[i] = (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; |
AVFrame *frame = data; |
int16_t *samples0; |
int16_t *samples1; |
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; |
} |
|
frame->nb_samples = ctx->max_frame_size; |
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) |
return ret; |
samples0 = (int16_t *)frame->data[0]; |
samples1 = (int16_t *)frame->data[1]; |
|
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, samples0 + ctx->sample_offset, |
samples1 + ctx->sample_offset) < 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]; |
} |
|
frame->nb_samples = ctx->sample_offset; |
*got_frame_ptr = ctx->sample_offset > 0; |
|
return avpkt->size; |
} |
|
static void decode_flush(AVCodecContext *avctx) |
{ |
RALFContext *ctx = avctx->priv_data; |
|
ctx->has_pkt = 0; |
} |
|
|
AVCodec ff_ralf_decoder = { |
.name = "ralf", |
.long_name = NULL_IF_CONFIG_SMALL("RealAudio Lossless"), |
.type = AVMEDIA_TYPE_AUDIO, |
.id = AV_CODEC_ID_RALF, |
.priv_data_size = sizeof(RALFContext), |
.init = decode_init, |
.close = decode_close, |
.decode = decode_frame, |
.flush = decode_flush, |
.capabilities = CODEC_CAP_DR1, |
.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P, |
AV_SAMPLE_FMT_NONE }, |
}; |