/*
* WMA compatible encoder
* Copyright (c) 2007 Michael Niedermayer
*
* 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
*/
#include "libavutil/attributes.h"
#include "libavutil/ffmath.h"
#include "avcodec.h"
#include "internal.h"
#include "wma.h"
#include "libavutil/avassert.h"
static av_cold int encode_init(AVCodecContext *avctx)
{
WMACodecContext *s = avctx->priv_data;
int i, flags1, flags2, block_align;
uint8_t *extradata;
int ret;
s->avctx = avctx;
if (avctx->channels > MAX_CHANNELS) {
av_log(avctx, AV_LOG_ERROR,
"too many channels: got %i, need %i or fewer\n",
avctx->channels, MAX_CHANNELS);
return AVERROR(EINVAL);
}
if (avctx->sample_rate > 48000) {
av_log(avctx, AV_LOG_ERROR, "sample rate is too high: %d > 48kHz\n",
avctx->sample_rate);
return AVERROR(EINVAL);
}
if (avctx->bit_rate < 24 * 1000) {
av_log(avctx, AV_LOG_ERROR,
"bitrate too low: got %"PRId64", need 24000 or higher\n",
(int64_t)avctx->bit_rate);
return AVERROR(EINVAL);
}
/* extract flag info */
flags1 = 0;
flags2 = 1;
if (avctx->codec->id == AV_CODEC_ID_WMAV1) {
extradata = av_malloc(4);
if (!extradata)
return AVERROR(ENOMEM);
avctx->extradata_size = 4;
AV_WL16(extradata, flags1);
AV_WL16(extradata + 2, flags2);
} else if (avctx->codec->id == AV_CODEC_ID_WMAV2) {
extradata = av_mallocz(10);
if (!extradata)
return AVERROR(ENOMEM);
avctx->extradata_size = 10;
AV_WL32(extradata, flags1);
AV_WL16(extradata + 4, flags2);
} else {
av_assert0(0);
}
avctx->extradata = extradata;
s->use_exp_vlc = flags2 & 0x0001;
s->use_bit_reservoir = flags2 & 0x0002;
s->use_variable_block_len = flags2 & 0x0004;
if (avctx->channels == 2)
s->ms_stereo = 1;
if ((ret = ff_wma_init(avctx, flags2)) < 0)
return ret;
/* init MDCT */
for (i = 0; i < s->nb_block_sizes; i++)
ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 0, 1.0);
block_align = avctx->bit_rate * (int64_t) s->frame_len /
(avctx->sample_rate * 8);
block_align = FFMIN(block_align, MAX_CODED_SUPERFRAME_SIZE);
avctx->block_align = block_align;
avctx->frame_size = avctx->initial_padding = s->frame_len;
return 0;
}
static int apply_window_and_mdct(AVCodecContext *avctx, const AVFrame *frame)
{
WMACodecContext *s = avctx->priv_data;
float **audio = (float **) frame->extended_data;
int len = frame->nb_samples;
int window_index = s->frame_len_bits - s->block_len_bits;
FFTContext *mdct = &s->mdct_ctx[window_index];
int ch;
const float *win = s->windows[window_index];
int window_len = 1 << s->block_len_bits;
float n = 2.0 * 32768.0 / window_len;
for (ch = 0; ch < avctx->channels; ch++) {
memcpy(s->output, s->frame_out[ch], window_len * sizeof(*s->output));
s->fdsp->vector_fmul_scalar(s->frame_out[ch], audio[ch], n, len);
s->fdsp->vector_fmul_reverse(&s->output[window_len], s->frame_out[ch],
win, len);
s->fdsp->vector_fmul(s->frame_out[ch], s->frame_out[ch], win, len);
mdct->mdct_calc(mdct, s->coefs[ch], s->output);
if (!isfinite(s->coefs[ch][0])) {
av_log(avctx, AV_LOG_ERROR, "Input contains NaN/+-Inf\n");
return AVERROR(EINVAL);
}
}
return 0;
}
// FIXME use for decoding too
static void init_exp(WMACodecContext *s, int ch, const int *exp_param)
{
int n;
const uint16_t *ptr;
float v, *q, max_scale, *q_end;
ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
q = s->exponents[ch];
q_end = q + s->block_len;
max_scale = 0;
while (q < q_end) {
/* XXX: use a table */
v = ff_exp10(*exp_param++ *(1.0 / 16.0));
max_scale = FFMAX(max_scale, v);
n = *ptr++;
do {
*q++ = v;
} while (--n);
}
s->max_exponent[ch] = max_scale;
}
static void encode_exp_vlc(WMACodecContext *s, int ch, const int *exp_param)
{
int last_exp;
const uint16_t *ptr;
float *q, *q_end;
ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
q = s->exponents[ch];
q_end = q + s->block_len;
if (s->version == 1) {
last_exp = *exp_param++;
av_assert0(last_exp - 10 >= 0 && last_exp - 10 < 32);
put_bits(&s->pb, 5, last_exp - 10);
q += *ptr++;
} else
last_exp = 36;
while (q < q_end) {
int exp = *exp_param++;
int code = exp - last_exp + 60;
av_assert1(code >= 0 && code < 120);
put_bits(&s->pb, ff_aac_scalefactor_bits[code],
ff_aac_scalefactor_code[code]);
/* XXX: use a table */
q += *ptr++;
last_exp = exp;
}
}
static int encode_block(WMACodecContext *s, float (*src_coefs)[BLOCK_MAX_SIZE],
int total_gain)
{
int v, bsize, ch, coef_nb_bits, parse_exponents;
float mdct_norm;
int nb_coefs[MAX_CHANNELS];
static const int fixed_exp[25] = {
20, 20, 20, 20, 20,
20, 20, 20, 20, 20,
20, 20, 20, 20, 20,
20, 20, 20, 20, 20,
20, 20, 20, 20, 20
};
// FIXME remove duplication relative to decoder
if (s->use_variable_block_len) {
av_assert0(0); // FIXME not implemented
} else {
/* fixed block len */
s->next_block_len_bits = s->frame_len_bits;
s->prev_block_len_bits = s->frame_len_bits;
s->block_len_bits = s->frame_len_bits;
}
s->block_len = 1 << s->block_len_bits;
// av_assert0((s->block_pos + s->block_len) <= s->frame_len);
bsize = s->frame_len_bits - s->block_len_bits;
// FIXME factor
v = s->coefs_end[bsize] - s->coefs_start;
for (ch = 0; ch < s->avctx->channels; ch++)
nb_coefs[ch] = v;
{
int n4 = s->block_len / 2;
mdct_norm = 1.0 / (float) n4;
if (s->version == 1)
mdct_norm *= sqrt(n4);
}
if (s->avctx->channels == 2)
put_bits(&s->pb, 1, !!s->ms_stereo);
for (ch = 0; ch < s->avctx->channels; ch++) {
// FIXME only set channel_coded when needed, instead of always
s->channel_coded[ch] = 1;
if (s->channel_coded[ch])
init_exp(s, ch, fixed_exp);
}
for (ch = 0; ch < s->avctx->channels; ch++) {
if (s->channel_coded[ch]) {
WMACoef *coefs1;
float *coefs, *exponents, mult;
int i, n;
coefs1 = s->coefs1[ch];
exponents = s->exponents[ch];
mult = ff_exp10(total_gain * 0.05) / s->max_exponent[ch];
mult *= mdct_norm;
coefs = src_coefs[ch];
if (s->use_noise_coding && 0) {
av_assert0(0); // FIXME not implemented
} else {
coefs += s->coefs_start;
n = nb_coefs[ch];
for (i = 0; i < n; i++) {
double t = *coefs++ / (exponents[i] * mult);
if (t < -32768 || t > 32767)
return -1;
coefs1[i] = lrint(t);
}
}
}
}
v = 0;
for (ch = 0; ch < s->avctx->channels; ch++) {
int a = s->channel_coded[ch];
put_bits(&s->pb, 1, a);
v |= a;
}
if (!v)
return 1;
for (v = total_gain - 1; v >= 127; v -= 127)
put_bits(&s->pb, 7, 127);
put_bits(&s->pb, 7, v);
coef_nb_bits = ff_wma_total_gain_to_bits(total_gain);
if (s->use_noise_coding) {
for (ch = 0; ch < s->avctx->channels; ch++) {
if (s->channel_coded[ch]) {
int i, n;
n = s->exponent_high_sizes[bsize];
for (i = 0; i < n; i++) {
put_bits(&s->pb, 1, s->high_band_coded[ch][i] = 0);
if (0)
nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
}
}
}
}
parse_exponents = 1;
if (s->block_len_bits != s->frame_len_bits)
put_bits(&s->pb, 1, parse_exponents);
if (parse_exponents) {
for (ch = 0; ch < s->avctx->channels; ch++) {
if (s->channel_coded[ch]) {
if (s->use_exp_vlc) {
encode_exp_vlc(s, ch, fixed_exp);
} else {
av_assert0(0); // FIXME not implemented
// encode_exp_lsp(s, ch);
}
}
}
} else
av_assert0(0); // FIXME not implemented
for (ch = 0; ch < s->avctx->channels; ch++) {
if (s->channel_coded[ch]) {
int run, tindex;
WMACoef *ptr, *eptr;
tindex = (ch == 1 && s->ms_stereo);
ptr = &s->coefs1[ch][0];
eptr = ptr + nb_coefs[ch];
run = 0;
for (; ptr < eptr; ptr++) {
if (*ptr) {
int level = *ptr;
int abs_level = FFABS(level);
int code = 0;
if (abs_level <= s->coef_vlcs[tindex]->max_level)
if (run < s->coef_vlcs[tindex]->levels[abs_level - 1])
code = run + s->int_table[tindex][abs_level - 1];
av_assert2(code < s->coef_vlcs[tindex]->n);
put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[code],
s->coef_vlcs[tindex]->huffcodes[code]);
if (code == 0) {
if (1 << coef_nb_bits <= abs_level)
return -1;
put_bits(&s->pb, coef_nb_bits, abs_level);
put_bits(&s->pb, s->frame_len_bits, run);
}
// FIXME the sign is flipped somewhere
put_bits(&s->pb, 1, level < 0);
run = 0;
} else
run++;
}
if (run)
put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[1],
s->coef_vlcs[tindex]->huffcodes[1]);
}
if (s->version == 1 && s->avctx->channels >= 2)
avpriv_align_put_bits(&s->pb);
}
return 0;
}
static int encode_frame(WMACodecContext *s, float (*src_coefs)[BLOCK_MAX_SIZE],
uint8_t *buf, int buf_size, int total_gain)
{
init_put_bits(&s->pb, buf, buf_size);
if (s->use_bit_reservoir)
av_assert0(0); // FIXME not implemented
else if (encode_block(s, src_coefs, total_gain) < 0)
return INT_MAX;
avpriv_align_put_bits(&s->pb);
return put_bits_count(&s->pb) / 8 - s->avctx->block_align;
}
static int encode_superframe(AVCodecContext *avctx, AVPacket *avpkt,
const AVFrame *frame, int *got_packet_ptr)
{
WMACodecContext *s = avctx->priv_data;
int i, total_gain, ret, error;
s->block_len_bits = s->frame_len_bits; // required by non variable block len
s->block_len = 1 << s->block_len_bits;
ret = apply_window_and_mdct(avctx, frame);
if (ret < 0)
return ret;
if (s->ms_stereo) {
float a, b;
int i;
for (i = 0; i < s->block_len; i++) {
a = s->coefs[0][i] * 0.5;
b = s->coefs[1][i] * 0.5;
s->coefs[0][i] = a + b;
s->coefs[1][i] = a - b;
}
}
if ((ret = ff_alloc_packet2(avctx, avpkt, 2 * MAX_CODED_SUPERFRAME_SIZE, 0)) < 0)
return ret;
total_gain = 128;
for (i = 64; i; i >>= 1) {
error = encode_frame(s, s->coefs, avpkt->data, avpkt->size,
total_gain - i);
if (error <= 0)
total_gain -= i;
}
while(total_gain <= 128 && error > 0)
error = encode_frame(s, s->coefs, avpkt->data, avpkt->size, total_gain++);
if (error > 0) {
av_log(avctx, AV_LOG_ERROR, "Invalid input data or requested bitrate too low, cannot encode\n");
avpkt->size = 0;
return AVERROR(EINVAL);
}
av_assert0((put_bits_count(&s->pb) & 7) == 0);
i= avctx->block_align - (put_bits_count(&s->pb)+7)/8;
av_assert0(i>=0);
while(i--)
put_bits(&s->pb, 8, 'N');
flush_put_bits(&s->pb);
av_assert0(put_bits_ptr(&s->pb) - s->pb.buf == avctx->block_align);
if (frame->pts != AV_NOPTS_VALUE)
avpkt->pts = frame->pts - ff_samples_to_time_base(avctx, avctx->initial_padding);
avpkt->size = avctx->block_align;
*got_packet_ptr = 1;
return 0;
}
#if CONFIG_WMAV1_ENCODER
AVCodec ff_wmav1_encoder = {
.name = "wmav1",
.long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 1"),
.type = AVMEDIA_TYPE_AUDIO,
.id = AV_CODEC_ID_WMAV1,
.priv_data_size = sizeof(WMACodecContext),
.init = encode_init,
.encode2 = encode_superframe,
.close = ff_wma_end,
.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
AV_SAMPLE_FMT_NONE },
};
#endif
#if CONFIG_WMAV2_ENCODER
AVCodec ff_wmav2_encoder = {
.name = "wmav2",
.long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 2"),
.type = AVMEDIA_TYPE_AUDIO,
.id = AV_CODEC_ID_WMAV2,
.priv_data_size = sizeof(WMACodecContext),
.init = encode_init,
.encode2 = encode_superframe,
.close = ff_wma_end,
.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
AV_SAMPLE_FMT_NONE },
};
#endif