/*
- * The simplest AC3 encoder
- * Copyright (c) 2000 Fabrice Bellard.
+ * The simplest AC-3 encoder
+ * Copyright (c) 2000 Fabrice Bellard
*
* This file is part of FFmpeg.
*
*/
/**
- * @file ac3enc.c
- * The simplest AC3 encoder.
+ * @file libavcodec/ac3enc.c
+ * The simplest AC-3 encoder.
*/
//#define DEBUG
//#define DEBUG_BITALLOC
+#include "libavutil/crc.h"
#include "avcodec.h"
-#include "bitstream.h"
-#include "crc.h"
+#include "get_bits.h" // for ff_reverse
+#include "put_bits.h"
#include "ac3.h"
+#include "audioconvert.h"
typedef struct AC3EncodeContext {
PutBitContext pb;
int nb_channels;
int nb_all_channels;
int lfe_channel;
+ const uint8_t *channel_map;
int bit_rate;
unsigned int sample_rate;
- unsigned int bsid;
+ unsigned int bitstream_id;
unsigned int frame_size_min; /* minimum frame size in case rounding is necessary */
unsigned int frame_size; /* current frame size in words */
unsigned int bits_written;
unsigned int samples_written;
- int halfratecod;
- unsigned int frmsizecod;
- unsigned int fscod; /* frequency */
- unsigned int acmod;
+ int sr_shift;
+ unsigned int frame_size_code;
+ unsigned int sr_code; /* frequency */
+ unsigned int channel_mode;
int lfe;
- unsigned int bsmod;
+ unsigned int bitstream_mode;
short last_samples[AC3_MAX_CHANNELS][256];
unsigned int chbwcod[AC3_MAX_CHANNELS];
int nb_coefs[AC3_MAX_CHANNELS];
/* bitrate allocation control */
- int sgaincod, sdecaycod, fdecaycod, dbkneecod, floorcod;
+ int slow_gain_code, slow_decay_code, fast_decay_code, db_per_bit_code, floor_code;
AC3BitAllocParameters bit_alloc;
- int csnroffst;
- int fgaincod[AC3_MAX_CHANNELS];
- int fsnroffst[AC3_MAX_CHANNELS];
+ int coarse_snr_offset;
+ int fast_gain_code[AC3_MAX_CHANNELS];
+ int fine_snr_offset[AC3_MAX_CHANNELS];
/* mantissa encoding */
int mant1_cnt, mant2_cnt, mant4_cnt;
} AC3EncodeContext;
static int16_t costab[64];
static int16_t sintab[64];
-static int16_t fft_rev[512];
static int16_t xcos1[128];
static int16_t xsin1[128];
/* new exponents are sent if their Norm 1 exceed this number */
#define EXP_DIFF_THRESHOLD 1000
-static void fft_init(int ln);
-
static inline int16_t fix15(float a)
{
int v;
short re,im;
} IComplex;
-static void fft_init(int ln)
+static av_cold void fft_init(int ln)
{
- int i, j, m, n;
+ int i, n;
float alpha;
n = 1 << ln;
costab[i] = fix15(cos(alpha));
sintab[i] = fix15(sin(alpha));
}
-
- for(i=0;i<n;i++) {
- m=0;
- for(j=0;j<ln;j++) {
- m |= ((i >> j) & 1) << (ln-j-1);
- }
- fft_rev[i]=m;
- }
}
/* butter fly op */
qim = (by - ay) >> 1;\
}
-#define MUL16(a,b) ((a) * (b))
-
#define CMUL(pre, pim, are, aim, bre, bim) \
{\
pre = (MUL16(are, bre) - MUL16(aim, bim)) >> 15;\
/* reverse */
for(j=0;j<np;j++) {
- int k;
- IComplex tmp;
- k = fft_rev[j];
- if (k < j) {
- tmp = z[k];
- z[k] = z[j];
- z[j] = tmp;
- }
+ int k = ff_reverse[j] >> (8 - ln);
+ if (k < j)
+ FFSWAP(IComplex, z[k], z[j]);
}
/* pass 0 */
int16_t mask[NB_BLOCKS][AC3_MAX_CHANNELS][50])
{
int blk, ch;
- int16_t bndpsd[NB_BLOCKS][AC3_MAX_CHANNELS][50];
+ int16_t band_psd[NB_BLOCKS][AC3_MAX_CHANNELS][50];
for(blk=0; blk<NB_BLOCKS; blk++) {
for(ch=0;ch<s->nb_all_channels;ch++) {
} else {
ff_ac3_bit_alloc_calc_psd(encoded_exp[blk][ch], 0,
s->nb_coefs[ch],
- psd[blk][ch], bndpsd[blk][ch]);
- ff_ac3_bit_alloc_calc_mask(&s->bit_alloc, bndpsd[blk][ch],
+ psd[blk][ch], band_psd[blk][ch]);
+ ff_ac3_bit_alloc_calc_mask(&s->bit_alloc, band_psd[blk][ch],
0, s->nb_coefs[ch],
- ff_fgaintab[s->fgaincod[ch]],
+ ff_ac3_fast_gain_tab[s->fast_gain_code[ch]],
ch == s->lfe_channel,
- 2, 0, NULL, NULL, NULL,
+ DBA_NONE, 0, NULL, NULL, NULL,
mask[blk][ch]);
}
}
int16_t mask[NB_BLOCKS][AC3_MAX_CHANNELS][50],
int16_t psd[NB_BLOCKS][AC3_MAX_CHANNELS][N/2],
uint8_t bap[NB_BLOCKS][AC3_MAX_CHANNELS][N/2],
- int frame_bits, int csnroffst, int fsnroffst)
+ int frame_bits, int coarse_snr_offset, int fine_snr_offset)
{
int i, ch;
- int snroffset;
+ int snr_offset;
- snroffset = (((csnroffst - 15) << 4) + fsnroffst) << 2;
+ snr_offset = (((coarse_snr_offset - 15) << 4) + fine_snr_offset) << 2;
/* compute size */
for(i=0;i<NB_BLOCKS;i++) {
s->mant2_cnt = 0;
s->mant4_cnt = 0;
for(ch=0;ch<s->nb_all_channels;ch++) {
- ff_ac3_bit_alloc_calc_bap(mask[i][ch], psd[i][ch],
- 0, s->nb_coefs[ch],
- snroffset,
- s->bit_alloc.floor, bap[i][ch]);
+ ff_ac3_bit_alloc_calc_bap(mask[i][ch], psd[i][ch], 0,
+ s->nb_coefs[ch], snr_offset,
+ s->bit_alloc.floor, ff_ac3_bap_tab,
+ bap[i][ch]);
frame_bits += compute_mantissa_size(s, bap[i][ch],
s->nb_coefs[ch]);
}
}
#if 0
printf("csnr=%d fsnr=%d frame_bits=%d diff=%d\n",
- csnroffst, fsnroffst, frame_bits,
+ coarse_snr_offset, fine_snr_offset, frame_bits,
16 * s->frame_size - ((frame_bits + 7) & ~7));
#endif
return 16 * s->frame_size - frame_bits;
int frame_bits)
{
int i, ch;
- int csnroffst, fsnroffst;
+ int coarse_snr_offset, fine_snr_offset;
uint8_t bap1[NB_BLOCKS][AC3_MAX_CHANNELS][N/2];
int16_t psd[NB_BLOCKS][AC3_MAX_CHANNELS][N/2];
int16_t mask[NB_BLOCKS][AC3_MAX_CHANNELS][50];
- static int frame_bits_inc[8] = { 0, 0, 2, 2, 2, 4, 2, 4 };
+ static const int frame_bits_inc[8] = { 0, 0, 2, 2, 2, 4, 2, 4 };
/* init default parameters */
- s->sdecaycod = 2;
- s->fdecaycod = 1;
- s->sgaincod = 1;
- s->dbkneecod = 2;
- s->floorcod = 4;
+ s->slow_decay_code = 2;
+ s->fast_decay_code = 1;
+ s->slow_gain_code = 1;
+ s->db_per_bit_code = 2;
+ s->floor_code = 4;
for(ch=0;ch<s->nb_all_channels;ch++)
- s->fgaincod[ch] = 4;
+ s->fast_gain_code[ch] = 4;
/* compute real values */
- s->bit_alloc.fscod = s->fscod;
- s->bit_alloc.halfratecod = s->halfratecod;
- s->bit_alloc.sdecay = ff_sdecaytab[s->sdecaycod] >> s->halfratecod;
- s->bit_alloc.fdecay = ff_fdecaytab[s->fdecaycod] >> s->halfratecod;
- s->bit_alloc.sgain = ff_sgaintab[s->sgaincod];
- s->bit_alloc.dbknee = ff_dbkneetab[s->dbkneecod];
- s->bit_alloc.floor = ff_floortab[s->floorcod];
+ s->bit_alloc.sr_code = s->sr_code;
+ s->bit_alloc.sr_shift = s->sr_shift;
+ s->bit_alloc.slow_decay = ff_ac3_slow_decay_tab[s->slow_decay_code] >> s->sr_shift;
+ s->bit_alloc.fast_decay = ff_ac3_fast_decay_tab[s->fast_decay_code] >> s->sr_shift;
+ s->bit_alloc.slow_gain = ff_ac3_slow_gain_tab[s->slow_gain_code];
+ s->bit_alloc.db_per_bit = ff_ac3_db_per_bit_tab[s->db_per_bit_code];
+ s->bit_alloc.floor = ff_ac3_floor_tab[s->floor_code];
/* header size */
frame_bits += 65;
- // if (s->acmod == 2)
+ // if (s->channel_mode == 2)
// frame_bits += 2;
- frame_bits += frame_bits_inc[s->acmod];
+ frame_bits += frame_bits_inc[s->channel_mode];
/* audio blocks */
for(i=0;i<NB_BLOCKS;i++) {
frame_bits += s->nb_channels * 2 + 2; /* blksw * c, dithflag * c, dynrnge, cplstre */
- if (s->acmod == 2) {
+ if (s->channel_mode == AC3_CHMODE_STEREO) {
frame_bits++; /* rematstr */
if(i==0) frame_bits += 4;
}
/* now the big work begins : do the bit allocation. Modify the snr
offset until we can pack everything in the requested frame size */
- csnroffst = s->csnroffst;
- while (csnroffst >= 0 &&
- bit_alloc(s, mask, psd, bap, frame_bits, csnroffst, 0) < 0)
- csnroffst -= SNR_INC1;
- if (csnroffst < 0) {
- av_log(NULL, AV_LOG_ERROR, "Bit allocation failed, try increasing the bitrate, -ab 384 for example!\n");
+ coarse_snr_offset = s->coarse_snr_offset;
+ while (coarse_snr_offset >= 0 &&
+ bit_alloc(s, mask, psd, bap, frame_bits, coarse_snr_offset, 0) < 0)
+ coarse_snr_offset -= SNR_INC1;
+ if (coarse_snr_offset < 0) {
+ av_log(NULL, AV_LOG_ERROR, "Bit allocation failed. Try increasing the bitrate.\n");
return -1;
}
- while ((csnroffst + SNR_INC1) <= 63 &&
+ while ((coarse_snr_offset + SNR_INC1) <= 63 &&
bit_alloc(s, mask, psd, bap1, frame_bits,
- csnroffst + SNR_INC1, 0) >= 0) {
- csnroffst += SNR_INC1;
+ coarse_snr_offset + SNR_INC1, 0) >= 0) {
+ coarse_snr_offset += SNR_INC1;
memcpy(bap, bap1, sizeof(bap1));
}
- while ((csnroffst + 1) <= 63 &&
- bit_alloc(s, mask, psd, bap1, frame_bits, csnroffst + 1, 0) >= 0) {
- csnroffst++;
+ while ((coarse_snr_offset + 1) <= 63 &&
+ bit_alloc(s, mask, psd, bap1, frame_bits, coarse_snr_offset + 1, 0) >= 0) {
+ coarse_snr_offset++;
memcpy(bap, bap1, sizeof(bap1));
}
- fsnroffst = 0;
- while ((fsnroffst + SNR_INC1) <= 15 &&
+ fine_snr_offset = 0;
+ while ((fine_snr_offset + SNR_INC1) <= 15 &&
bit_alloc(s, mask, psd, bap1, frame_bits,
- csnroffst, fsnroffst + SNR_INC1) >= 0) {
- fsnroffst += SNR_INC1;
+ coarse_snr_offset, fine_snr_offset + SNR_INC1) >= 0) {
+ fine_snr_offset += SNR_INC1;
memcpy(bap, bap1, sizeof(bap1));
}
- while ((fsnroffst + 1) <= 15 &&
+ while ((fine_snr_offset + 1) <= 15 &&
bit_alloc(s, mask, psd, bap1, frame_bits,
- csnroffst, fsnroffst + 1) >= 0) {
- fsnroffst++;
+ coarse_snr_offset, fine_snr_offset + 1) >= 0) {
+ fine_snr_offset++;
memcpy(bap, bap1, sizeof(bap1));
}
- s->csnroffst = csnroffst;
+ s->coarse_snr_offset = coarse_snr_offset;
for(ch=0;ch<s->nb_all_channels;ch++)
- s->fsnroffst[ch] = fsnroffst;
+ s->fine_snr_offset[ch] = fine_snr_offset;
#if defined(DEBUG_BITALLOC)
{
int j;
return 0;
}
-static int AC3_encode_init(AVCodecContext *avctx)
+static av_cold int set_channel_info(AC3EncodeContext *s, int channels,
+ int64_t *channel_layout)
+{
+ int ch_layout;
+
+ if (channels < 1 || channels > AC3_MAX_CHANNELS)
+ return -1;
+ if ((uint64_t)*channel_layout > 0x7FF)
+ return -1;
+ ch_layout = *channel_layout;
+ if (!ch_layout)
+ ch_layout = avcodec_guess_channel_layout(channels, CODEC_ID_AC3, NULL);
+ if (avcodec_channel_layout_num_channels(ch_layout) != channels)
+ return -1;
+
+ s->lfe = !!(ch_layout & CH_LOW_FREQUENCY);
+ s->nb_all_channels = channels;
+ s->nb_channels = channels - s->lfe;
+ s->lfe_channel = s->lfe ? s->nb_channels : -1;
+ if (s->lfe)
+ ch_layout -= CH_LOW_FREQUENCY;
+
+ switch (ch_layout) {
+ case CH_LAYOUT_MONO: s->channel_mode = AC3_CHMODE_MONO; break;
+ case CH_LAYOUT_STEREO: s->channel_mode = AC3_CHMODE_STEREO; break;
+ case CH_LAYOUT_SURROUND: s->channel_mode = AC3_CHMODE_3F; break;
+ case CH_LAYOUT_2_1: s->channel_mode = AC3_CHMODE_2F1R; break;
+ case CH_LAYOUT_4POINT0: s->channel_mode = AC3_CHMODE_3F1R; break;
+ case CH_LAYOUT_QUAD:
+ case CH_LAYOUT_2_2: s->channel_mode = AC3_CHMODE_2F2R; break;
+ case CH_LAYOUT_5POINT0:
+ case CH_LAYOUT_5POINT0_BACK: s->channel_mode = AC3_CHMODE_3F2R; break;
+ default:
+ return -1;
+ }
+
+ s->channel_map = ff_ac3_enc_channel_map[s->channel_mode][s->lfe];
+ *channel_layout = ch_layout;
+ if (s->lfe)
+ *channel_layout |= CH_LOW_FREQUENCY;
+
+ return 0;
+}
+
+static av_cold int AC3_encode_init(AVCodecContext *avctx)
{
int freq = avctx->sample_rate;
int bitrate = avctx->bit_rate;
- int channels = avctx->channels;
AC3EncodeContext *s = avctx->priv_data;
int i, j, ch;
float alpha;
- static const uint8_t acmod_defs[6] = {
- 0x01, /* C */
- 0x02, /* L R */
- 0x03, /* L C R */
- 0x06, /* L R SL SR */
- 0x07, /* L C R SL SR */
- 0x07, /* L C R SL SR (+LFE) */
- };
+ int bw_code;
avctx->frame_size = AC3_FRAME_SIZE;
ac3_common_init();
- /* number of channels */
- if (channels < 1 || channels > 6)
+ if (!avctx->channel_layout) {
+ av_log(avctx, AV_LOG_WARNING, "No channel layout specified. The "
+ "encoder will guess the layout, but it "
+ "might be incorrect.\n");
+ }
+ if (set_channel_info(s, avctx->channels, &avctx->channel_layout)) {
+ av_log(avctx, AV_LOG_ERROR, "invalid channel layout\n");
return -1;
- s->acmod = acmod_defs[channels - 1];
- s->lfe = (channels == 6) ? 1 : 0;
- s->nb_all_channels = channels;
- s->nb_channels = channels > 5 ? 5 : channels;
- s->lfe_channel = s->lfe ? 5 : -1;
+ }
/* frequency */
for(i=0;i<3;i++) {
for(j=0;j<3;j++)
- if ((ff_ac3_freqs[j] >> i) == freq)
+ if ((ff_ac3_sample_rate_tab[j] >> i) == freq)
goto found;
}
return -1;
found:
s->sample_rate = freq;
- s->halfratecod = i;
- s->fscod = j;
- s->bsid = 8 + s->halfratecod;
- s->bsmod = 0; /* complete main audio service */
+ s->sr_shift = i;
+ s->sr_code = j;
+ s->bitstream_id = 8 + s->sr_shift;
+ s->bitstream_mode = 0; /* complete main audio service */
/* bitrate & frame size */
- bitrate /= 1000;
for(i=0;i<19;i++) {
- if ((ff_ac3_bitratetab[i] >> s->halfratecod) == bitrate)
+ if ((ff_ac3_bitrate_tab[i] >> s->sr_shift)*1000 == bitrate)
break;
}
if (i == 19)
return -1;
s->bit_rate = bitrate;
- s->frmsizecod = i << 1;
- s->frame_size_min = ff_ac3_frame_sizes[s->frmsizecod][s->fscod];
+ s->frame_size_code = i << 1;
+ s->frame_size_min = ff_ac3_frame_size_tab[s->frame_size_code][s->sr_code];
s->bits_written = 0;
s->samples_written = 0;
s->frame_size = s->frame_size_min;
/* bit allocation init */
+ if(avctx->cutoff) {
+ /* calculate bandwidth based on user-specified cutoff frequency */
+ int cutoff = av_clip(avctx->cutoff, 1, s->sample_rate >> 1);
+ int fbw_coeffs = cutoff * 512 / s->sample_rate;
+ bw_code = av_clip((fbw_coeffs - 73) / 3, 0, 60);
+ } else {
+ /* use default bandwidth setting */
+ /* XXX: should compute the bandwidth according to the frame
+ size, so that we avoid annoying high frequency artifacts */
+ bw_code = 50;
+ }
for(ch=0;ch<s->nb_channels;ch++) {
/* bandwidth for each channel */
- /* XXX: should compute the bandwidth according to the frame
- size, so that we avoid anoying high freq artefacts */
- s->chbwcod[ch] = 50; /* sample bandwidth as mpeg audio layer 2 table 0 */
- s->nb_coefs[ch] = ((s->chbwcod[ch] + 12) * 3) + 37;
+ s->chbwcod[ch] = bw_code;
+ s->nb_coefs[ch] = bw_code * 3 + 73;
}
if (s->lfe) {
s->nb_coefs[s->lfe_channel] = 7; /* fixed */
}
/* initial snr offset */
- s->csnroffst = 40;
+ s->coarse_snr_offset = 40;
/* mdct init */
fft_init(MDCT_NBITS - 2);
return 0;
}
-/* output the AC3 frame header */
+/* output the AC-3 frame header */
static void output_frame_header(AC3EncodeContext *s, unsigned char *frame)
{
init_put_bits(&s->pb, frame, AC3_MAX_CODED_FRAME_SIZE);
put_bits(&s->pb, 16, 0x0b77); /* frame header */
put_bits(&s->pb, 16, 0); /* crc1: will be filled later */
- put_bits(&s->pb, 2, s->fscod);
- put_bits(&s->pb, 6, s->frmsizecod + (s->frame_size - s->frame_size_min));
- put_bits(&s->pb, 5, s->bsid);
- put_bits(&s->pb, 3, s->bsmod);
- put_bits(&s->pb, 3, s->acmod);
- if ((s->acmod & 0x01) && s->acmod != 0x01)
+ put_bits(&s->pb, 2, s->sr_code);
+ put_bits(&s->pb, 6, s->frame_size_code + (s->frame_size - s->frame_size_min));
+ put_bits(&s->pb, 5, s->bitstream_id);
+ put_bits(&s->pb, 3, s->bitstream_mode);
+ put_bits(&s->pb, 3, s->channel_mode);
+ if ((s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO)
put_bits(&s->pb, 2, 1); /* XXX -4.5 dB */
- if (s->acmod & 0x04)
+ if (s->channel_mode & 0x04)
put_bits(&s->pb, 2, 1); /* XXX -6 dB */
- if (s->acmod == 0x02)
+ if (s->channel_mode == AC3_CHMODE_STEREO)
put_bits(&s->pb, 2, 0); /* surround not indicated */
put_bits(&s->pb, 1, s->lfe); /* LFE */
put_bits(&s->pb, 5, 31); /* dialog norm: -31 db */
put_bits(&s->pb, 1, 1); /* original bitstream */
put_bits(&s->pb, 1, 0); /* no time code 1 */
put_bits(&s->pb, 1, 0); /* no time code 2 */
- put_bits(&s->pb, 1, 0); /* no addtional bit stream info */
+ put_bits(&s->pb, 1, 0); /* no additional bit stream info */
}
/* symetric quantization on 'levels' levels */
return v & ((1 << qbits)-1);
}
-/* Output one audio block. There are NB_BLOCKS audio blocks in one AC3
+/* Output one audio block. There are NB_BLOCKS audio blocks in one AC-3
frame */
static void output_audio_block(AC3EncodeContext *s,
uint8_t exp_strategy[AC3_MAX_CHANNELS],
put_bits(&s->pb, 1, 0); /* no new coupling strategy */
}
- if (s->acmod == 2)
+ if (s->channel_mode == AC3_CHMODE_STEREO)
{
if(block_num==0)
{
baie = (block_num == 0);
put_bits(&s->pb, 1, baie);
if (baie) {
- put_bits(&s->pb, 2, s->sdecaycod);
- put_bits(&s->pb, 2, s->fdecaycod);
- put_bits(&s->pb, 2, s->sgaincod);
- put_bits(&s->pb, 2, s->dbkneecod);
- put_bits(&s->pb, 3, s->floorcod);
+ put_bits(&s->pb, 2, s->slow_decay_code);
+ put_bits(&s->pb, 2, s->fast_decay_code);
+ put_bits(&s->pb, 2, s->slow_gain_code);
+ put_bits(&s->pb, 2, s->db_per_bit_code);
+ put_bits(&s->pb, 3, s->floor_code);
}
/* snr offset */
put_bits(&s->pb, 1, baie); /* always present with bai */
if (baie) {
- put_bits(&s->pb, 6, s->csnroffst);
+ put_bits(&s->pb, 6, s->coarse_snr_offset);
for(ch=0;ch<s->nb_all_channels;ch++) {
- put_bits(&s->pb, 4, s->fsnroffst[ch]);
- put_bits(&s->pb, 3, s->fgaincod[ch]);
+ put_bits(&s->pb, 4, s->fine_snr_offset[ch]);
+ put_bits(&s->pb, 3, s->fast_gain_code[ch]);
}
}
flush_put_bits(&s->pb);
/* add zero bytes to reach the frame size */
frame = s->pb.buf;
- n = 2 * s->frame_size - (pbBufPtr(&s->pb) - frame) - 2;
+ n = 2 * s->frame_size - (put_bits_ptr(&s->pb) - frame) - 2;
assert(n >= 0);
if(n>0)
- memset(pbBufPtr(&s->pb), 0, n);
+ memset(put_bits_ptr(&s->pb), 0, n);
/* Now we must compute both crcs : this is not so easy for crc1
because it is at the beginning of the data... */
frame_size_58 = (frame_size >> 1) + (frame_size >> 3);
- crc1 = bswap_16(av_crc(av_crc8005, 0, frame + 4, 2 * frame_size_58 - 4));
+ crc1 = bswap_16(av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0,
+ frame + 4, 2 * frame_size_58 - 4));
/* XXX: could precompute crc_inv */
crc_inv = pow_poly((CRC16_POLY >> 1), (16 * frame_size_58) - 16, CRC16_POLY);
crc1 = mul_poly(crc_inv, crc1, CRC16_POLY);
- frame[2] = crc1 >> 8;
- frame[3] = crc1;
+ AV_WB16(frame+2,crc1);
- crc2 = bswap_16(av_crc(av_crc8005, 0, frame + 2 * frame_size_58, (frame_size - frame_size_58) * 2 - 2));
- frame[2*frame_size - 2] = crc2 >> 8;
- frame[2*frame_size - 1] = crc2;
+ crc2 = bswap_16(av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0,
+ frame + 2 * frame_size_58,
+ (frame_size - frame_size_58) * 2 - 2));
+ AV_WB16(frame+2*frame_size-2,crc2);
// printf("n=%d frame_size=%d\n", n, frame_size);
return frame_size * 2;
frame_bits = 0;
for(ch=0;ch<s->nb_all_channels;ch++) {
+ int ich = s->channel_map[ch];
/* fixed mdct to the six sub blocks & exponent computation */
for(i=0;i<NB_BLOCKS;i++) {
int16_t *sptr;
int sinc;
/* compute input samples */
- memcpy(input_samples, s->last_samples[ch], N/2 * sizeof(int16_t));
+ memcpy(input_samples, s->last_samples[ich], N/2 * sizeof(int16_t));
sinc = s->nb_all_channels;
- sptr = samples + (sinc * (N/2) * i) + ch;
+ sptr = samples + (sinc * (N/2) * i) + ich;
for(j=0;j<N/2;j++) {
v = *sptr;
input_samples[j + N/2] = v;
- s->last_samples[ch][j] = v;
+ s->last_samples[ich][j] = v;
sptr += sinc;
}
}
/* adjust for fractional frame sizes */
- while(s->bits_written >= s->bit_rate*1000 && s->samples_written >= s->sample_rate) {
- s->bits_written -= s->bit_rate*1000;
+ while(s->bits_written >= s->bit_rate && s->samples_written >= s->sample_rate) {
+ s->bits_written -= s->bit_rate;
s->samples_written -= s->sample_rate;
}
- s->frame_size = s->frame_size_min + (s->bits_written * s->sample_rate < s->samples_written * s->bit_rate*1000);
+ s->frame_size = s->frame_size_min + (s->bits_written * s->sample_rate < s->samples_written * s->bit_rate);
s->bits_written += s->frame_size * 16;
s->samples_written += AC3_FRAME_SIZE;
return output_frame_end(s);
}
-static int AC3_encode_close(AVCodecContext *avctx)
+static av_cold int AC3_encode_close(AVCodecContext *avctx)
{
av_freep(&avctx->coded_frame);
return 0;
/*************************************************************************/
/* TEST */
+#undef random
#define FN (N/4)
void fft_test(void)
AC3_encode_frame,
AC3_encode_close,
NULL,
+ .sample_fmts = (enum SampleFormat[]){SAMPLE_FMT_S16,SAMPLE_FMT_NONE},
+ .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52A (AC-3)"),
+ .channel_layouts = (int64_t[]){
+ CH_LAYOUT_MONO,
+ CH_LAYOUT_STEREO,
+ CH_LAYOUT_2_1,
+ CH_LAYOUT_SURROUND,
+ CH_LAYOUT_2_2,
+ CH_LAYOUT_QUAD,
+ CH_LAYOUT_4POINT0,
+ CH_LAYOUT_5POINT0,
+ CH_LAYOUT_5POINT0_BACK,
+ (CH_LAYOUT_MONO | CH_LOW_FREQUENCY),
+ (CH_LAYOUT_STEREO | CH_LOW_FREQUENCY),
+ (CH_LAYOUT_2_1 | CH_LOW_FREQUENCY),
+ (CH_LAYOUT_SURROUND | CH_LOW_FREQUENCY),
+ (CH_LAYOUT_2_2 | CH_LOW_FREQUENCY),
+ (CH_LAYOUT_QUAD | CH_LOW_FREQUENCY),
+ (CH_LAYOUT_4POINT0 | CH_LOW_FREQUENCY),
+ CH_LAYOUT_5POINT1,
+ CH_LAYOUT_5POINT1_BACK,
+ 0 },
};
projects / frescor / ffmpeg.git / blobdiff