From 5ce21342589a93e1713e4e2169f1327be5bf38e5 Mon Sep 17 00:00:00 2001 From: Justin Ruggles Date: Sun, 9 Dec 2007 03:23:04 +0000 Subject: [PATCH] cosmetics: rename ac3 bit allocation variables Originally committed as revision 11194 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/ac3.c | 112 +++++++++++++++++------------------ libavcodec/ac3.h | 49 +++++++-------- libavcodec/ac3_parser.c | 28 ++++----- libavcodec/ac3dec.c | 68 ++++++++++----------- libavcodec/ac3enc.c | 128 ++++++++++++++++++++-------------------- 5 files changed, 193 insertions(+), 192 deletions(-) diff --git a/libavcodec/ac3.c b/libavcodec/ac3.c index cc436c7e1a..cc80277bc6 100644 --- a/libavcodec/ac3.c +++ b/libavcodec/ac3.c @@ -28,8 +28,8 @@ #include "ac3.h" #include "bitstream.h" -static uint8_t bndtab[51]; -static uint8_t masktab[253]; +static uint8_t band_start_tab[51]; +static uint8_t bin_to_band_tab[253]; static inline int calc_lowcomp1(int a, int b0, int b1, int c) { @@ -53,7 +53,7 @@ static inline int calc_lowcomp(int a, int b0, int b1, int bin) } void ff_ac3_bit_alloc_calc_psd(int8_t *exp, int start, int end, int16_t *psd, - int16_t *bndpsd) + int16_t *band_psd) { int bin, i, j, k, end1, v; @@ -64,26 +64,26 @@ void ff_ac3_bit_alloc_calc_psd(int8_t *exp, int start, int end, int16_t *psd, /* PSD integration */ j=start; - k=masktab[start]; + k=bin_to_band_tab[start]; do { v=psd[j]; j++; - end1 = FFMIN(bndtab[k+1], end); + end1 = FFMIN(band_start_tab[k+1], end); for(i=j;i> 1, 255); v = FFMAX(v, psd[j]) + ff_ac3_log_add_tab[adr]; j++; } - bndpsd[k]=v; + band_psd[k]=v; k++; - } while (end > bndtab[k]); + } while (end > band_start_tab[k]); } -void ff_ac3_bit_alloc_calc_mask(AC3BitAllocParameters *s, int16_t *bndpsd, - int start, int end, int fgain, int is_lfe, - int deltbae, int deltnseg, uint8_t *deltoffst, - uint8_t *deltlen, uint8_t *deltba, +void ff_ac3_bit_alloc_calc_mask(AC3BitAllocParameters *s, int16_t *band_psd, + int start, int end, int fast_gain, int is_lfe, + int dba_mode, int dba_nsegs, uint8_t *dba_offsets, + uint8_t *dba_lengths, uint8_t *dba_values, int16_t *mask) { int16_t excite[50]; /* excitation */ @@ -92,24 +92,24 @@ void ff_ac3_bit_alloc_calc_mask(AC3BitAllocParameters *s, int16_t *bndpsd, int lowcomp, fastleak, slowleak; /* excitation function */ - bndstrt = masktab[start]; - bndend = masktab[end-1] + 1; + bndstrt = bin_to_band_tab[start]; + bndend = bin_to_band_tab[end-1] + 1; if (bndstrt == 0) { lowcomp = 0; - lowcomp = calc_lowcomp1(lowcomp, bndpsd[0], bndpsd[1], 384); - excite[0] = bndpsd[0] - fgain - lowcomp; - lowcomp = calc_lowcomp1(lowcomp, bndpsd[1], bndpsd[2], 384); - excite[1] = bndpsd[1] - fgain - lowcomp; + lowcomp = calc_lowcomp1(lowcomp, band_psd[0], band_psd[1], 384); + excite[0] = band_psd[0] - fast_gain - lowcomp; + lowcomp = calc_lowcomp1(lowcomp, band_psd[1], band_psd[2], 384); + excite[1] = band_psd[1] - fast_gain - lowcomp; begin = 7; for (bin = 2; bin < 7; bin++) { if (!(is_lfe && bin == 6)) - lowcomp = calc_lowcomp1(lowcomp, bndpsd[bin], bndpsd[bin+1], 384); - fastleak = bndpsd[bin] - fgain; - slowleak = bndpsd[bin] - s->sgain; + lowcomp = calc_lowcomp1(lowcomp, band_psd[bin], band_psd[bin+1], 384); + fastleak = band_psd[bin] - fast_gain; + slowleak = band_psd[bin] - s->slow_gain; excite[bin] = fastleak - lowcomp; if (!(is_lfe && bin == 6)) { - if (bndpsd[bin] <= bndpsd[bin+1]) { + if (band_psd[bin] <= band_psd[bin+1]) { begin = bin + 1; break; } @@ -121,10 +121,10 @@ void ff_ac3_bit_alloc_calc_mask(AC3BitAllocParameters *s, int16_t *bndpsd, for (bin = begin; bin < end1; bin++) { if (!(is_lfe && bin == 6)) - lowcomp = calc_lowcomp(lowcomp, bndpsd[bin], bndpsd[bin+1], bin); + lowcomp = calc_lowcomp(lowcomp, band_psd[bin], band_psd[bin+1], bin); - fastleak = FFMAX(fastleak - s->fdecay, bndpsd[bin] - fgain); - slowleak = FFMAX(slowleak - s->sdecay, bndpsd[bin] - s->sgain); + fastleak = FFMAX(fastleak - s->fast_decay, band_psd[bin] - fast_gain); + slowleak = FFMAX(slowleak - s->slow_decay, band_psd[bin] - s->slow_gain); excite[bin] = FFMAX(fastleak - lowcomp, slowleak); } begin = 22; @@ -132,39 +132,39 @@ void ff_ac3_bit_alloc_calc_mask(AC3BitAllocParameters *s, int16_t *bndpsd, /* coupling channel */ begin = bndstrt; - fastleak = (s->cplfleak << 8) + 768; - slowleak = (s->cplsleak << 8) + 768; + fastleak = (s->cpl_fast_leak << 8) + 768; + slowleak = (s->cpl_slow_leak << 8) + 768; } for (bin = begin; bin < bndend; bin++) { - fastleak = FFMAX(fastleak - s->fdecay, bndpsd[bin] - fgain); - slowleak = FFMAX(slowleak - s->sdecay, bndpsd[bin] - s->sgain); + fastleak = FFMAX(fastleak - s->fast_decay, band_psd[bin] - fast_gain); + slowleak = FFMAX(slowleak - s->slow_decay, band_psd[bin] - s->slow_gain); excite[bin] = FFMAX(fastleak, slowleak); } /* compute masking curve */ for (bin = bndstrt; bin < bndend; bin++) { - tmp = s->dbknee - bndpsd[bin]; + tmp = s->db_per_bit - band_psd[bin]; if (tmp > 0) { excite[bin] += tmp >> 2; } - mask[bin] = FFMAX(ff_ac3_hearing_threshold_tab[bin >> s->halfratecod][s->fscod], excite[bin]); + mask[bin] = FFMAX(ff_ac3_hearing_threshold_tab[bin >> s->sr_shift][s->sr_code], excite[bin]); } /* delta bit allocation */ - if (deltbae == DBA_REUSE || deltbae == DBA_NEW) { + if (dba_mode == DBA_REUSE || dba_mode == DBA_NEW) { int band, seg, delta; band = 0; - for (seg = 0; seg < deltnseg; seg++) { - band += deltoffst[seg]; - if (deltba[seg] >= 4) { - delta = (deltba[seg] - 3) << 7; + for (seg = 0; seg < dba_nsegs; seg++) { + band += dba_offsets[seg]; + if (dba_values[seg] >= 4) { + delta = (dba_values[seg] - 3) << 7; } else { - delta = (deltba[seg] - 4) << 7; + delta = (dba_values[seg] - 4) << 7; } - for (k = 0; k < deltlen[seg]; k++) { + for (k = 0; k < dba_lengths[seg]; k++) { mask[band] += delta; band++; } @@ -173,49 +173,49 @@ void ff_ac3_bit_alloc_calc_mask(AC3BitAllocParameters *s, int16_t *bndpsd, } void ff_ac3_bit_alloc_calc_bap(int16_t *mask, int16_t *psd, int start, int end, - int snroffset, int floor, uint8_t *bap) + int snr_offset, int floor, uint8_t *bap) { int i, j, k, end1, v, address; - /* special case, if snroffset is -960, set all bap's to zero */ - if(snroffset == -960) { + /* special case, if snr offset is -960, set all bap's to zero */ + if(snr_offset == -960) { memset(bap, 0, 256); return; } i = start; - j = masktab[start]; + j = bin_to_band_tab[start]; do { - v = (FFMAX(mask[j] - snroffset - floor, 0) & 0x1FE0) + floor; - end1 = FFMIN(bndtab[j] + ff_ac3_critical_band_size_tab[j], end); + v = (FFMAX(mask[j] - snr_offset - floor, 0) & 0x1FE0) + floor; + end1 = FFMIN(band_start_tab[j] + ff_ac3_critical_band_size_tab[j], end); for (k = i; k < end1; k++) { address = av_clip((psd[i] - v) >> 5, 0, 63); bap[i] = ff_ac3_bap_tab[address]; i++; } - } while (end > bndtab[j++]); + } while (end > band_start_tab[j++]); } /* AC3 bit allocation. The algorithm is the one described in the AC3 spec. */ void ac3_parametric_bit_allocation(AC3BitAllocParameters *s, uint8_t *bap, int8_t *exp, int start, int end, - int snroffset, int fgain, int is_lfe, - int deltbae,int deltnseg, - uint8_t *deltoffst, uint8_t *deltlen, - uint8_t *deltba) + int snr_offset, int fast_gain, int is_lfe, + int dba_mode, int dba_nsegs, + uint8_t *dba_offsets, uint8_t *dba_lengths, + uint8_t *dba_values) { int16_t psd[256]; /* scaled exponents */ - int16_t bndpsd[50]; /* interpolated exponents */ + int16_t band_psd[50]; /* interpolated exponents */ int16_t mask[50]; /* masking value */ - ff_ac3_bit_alloc_calc_psd(exp, start, end, psd, bndpsd); + ff_ac3_bit_alloc_calc_psd(exp, start, end, psd, band_psd); - ff_ac3_bit_alloc_calc_mask(s, bndpsd, start, end, fgain, is_lfe, - deltbae, deltnseg, deltoffst, deltlen, deltba, + ff_ac3_bit_alloc_calc_mask(s, band_psd, start, end, fast_gain, is_lfe, + dba_mode, dba_nsegs, dba_offsets, dba_lengths, dba_values, mask); - ff_ac3_bit_alloc_calc_bap(mask, psd, start, end, snroffset, s->floor, bap); + ff_ac3_bit_alloc_calc_bap(mask, psd, start, end, snr_offset, s->floor, bap); } /** @@ -230,10 +230,10 @@ void ac3_common_init(void) k = 0; l = 0; for(i=0;i<50;i++) { - bndtab[i] = l; + band_start_tab[i] = l; v = ff_ac3_critical_band_size_tab[i]; - for(j=0;jcrc1 = get_bits(&gbc, 16); - hdr->fscod = get_bits(&gbc, 2); - if(hdr->fscod == 3) + hdr->sr_code = get_bits(&gbc, 2); + if(hdr->sr_code == 3) return AC3_PARSE_ERROR_SAMPLE_RATE; hdr->frmsizecod = get_bits(&gbc, 6); @@ -75,11 +75,11 @@ int ff_ac3_parse_header(const uint8_t buf[7], AC3HeaderInfo *hdr) } hdr->lfeon = get_bits1(&gbc); - hdr->halfratecod = FFMAX(hdr->bsid, 8) - 8; - hdr->sample_rate = ff_ac3_sample_rate_tab[hdr->fscod] >> hdr->halfratecod; - hdr->bit_rate = (ff_ac3_bitrate_tab[hdr->frmsizecod>>1] * 1000) >> hdr->halfratecod; + hdr->sr_shift = FFMAX(hdr->bsid, 8) - 8; + hdr->sample_rate = ff_ac3_sample_rate_tab[hdr->sr_code] >> hdr->sr_shift; + hdr->bit_rate = (ff_ac3_bitrate_tab[hdr->frmsizecod>>1] * 1000) >> hdr->sr_shift; hdr->channels = ff_ac3_channels_tab[hdr->acmod] + hdr->lfeon; - hdr->frame_size = ff_ac3_frame_size_tab[hdr->frmsizecod][hdr->fscod] * 2; + hdr->frame_size = ff_ac3_frame_size_tab[hdr->frmsizecod][hdr->sr_code] * 2; return 0; } @@ -88,8 +88,8 @@ static int ac3_sync(const uint8_t *buf, int *channels, int *sample_rate, int *bit_rate, int *samples) { int err; - unsigned int fscod, acmod, bsid, lfeon; - unsigned int strmtyp, substreamid, frmsiz, fscod2, numblkscod; + unsigned int sr_code, acmod, bsid, lfeon; + unsigned int strmtyp, substreamid, frmsiz, sr_code2, numblkscod; GetBitContext bits; AC3HeaderInfo hdr; @@ -117,19 +117,19 @@ static int ac3_sync(const uint8_t *buf, int *channels, int *sample_rate, if(frmsiz*2 < AC3_HEADER_SIZE) return 0; - fscod = get_bits(&bits, 2); - if (fscod == 3) { - fscod2 = get_bits(&bits, 2); + sr_code = get_bits(&bits, 2); + if (sr_code == 3) { + sr_code2 = get_bits(&bits, 2); numblkscod = 3; - if(fscod2 == 3) + if(sr_code2 == 3) return 0; - *sample_rate = ff_ac3_sample_rate_tab[fscod2] / 2; + *sample_rate = ff_ac3_sample_rate_tab[sr_code2] / 2; } else { numblkscod = get_bits(&bits, 2); - *sample_rate = ff_ac3_sample_rate_tab[fscod]; + *sample_rate = ff_ac3_sample_rate_tab[sr_code]; } acmod = get_bits(&bits, 3); diff --git a/libavcodec/ac3dec.c b/libavcodec/ac3dec.c index be061854ec..f667608975 100644 --- a/libavcodec/ac3dec.c +++ b/libavcodec/ac3dec.c @@ -141,13 +141,13 @@ typedef struct { int nrematbnd; ///< number of rematrixing bands int rematflg[4]; ///< rematrixing flags int expstr[AC3_MAX_CHANNELS]; ///< exponent strategies - int snroffst[AC3_MAX_CHANNELS]; ///< signal-to-noise ratio offsets - int fgain[AC3_MAX_CHANNELS]; ///< fast gain values (signal-to-mask ratio) - int deltbae[AC3_MAX_CHANNELS]; ///< delta bit allocation exists - int deltnseg[AC3_MAX_CHANNELS]; ///< number of delta segments - uint8_t deltoffst[AC3_MAX_CHANNELS][8]; ///< delta segment offsets - uint8_t deltlen[AC3_MAX_CHANNELS][8]; ///< delta segment lengths - uint8_t deltba[AC3_MAX_CHANNELS][8]; ///< delta values for each segment + int snr_offset[AC3_MAX_CHANNELS]; ///< signal-to-noise ratio offsets + int fast_gain[AC3_MAX_CHANNELS]; ///< fast gain values (signal-to-mask ratio) + int dba_mode[AC3_MAX_CHANNELS]; ///< delta bit allocation mode + int dba_nsegs[AC3_MAX_CHANNELS]; ///< number of delta segments + uint8_t dba_offsets[AC3_MAX_CHANNELS][8]; ///< delta segment offsets + uint8_t dba_lengths[AC3_MAX_CHANNELS][8]; ///< delta segment lengths + uint8_t dba_values[AC3_MAX_CHANNELS][8]; ///< delta values for each segment int sampling_rate; ///< sample frequency, in Hz int bit_rate; ///< stream bit rate, in bits-per-second @@ -173,7 +173,7 @@ typedef struct { int8_t dexps[AC3_MAX_CHANNELS][256]; ///< decoded exponents uint8_t bap[AC3_MAX_CHANNELS][256]; ///< bit allocation pointers int16_t psd[AC3_MAX_CHANNELS][256]; ///< scaled exponents - int16_t bndpsd[AC3_MAX_CHANNELS][50]; ///< interpolated exponents + int16_t band_psd[AC3_MAX_CHANNELS][50]; ///< interpolated exponents int16_t mask[AC3_MAX_CHANNELS][50]; ///< masking curve values DECLARE_ALIGNED_16(float, transform_coeffs[AC3_MAX_CHANNELS][256]); ///< transform coefficients @@ -344,13 +344,13 @@ static int ac3_parse_header(AC3DecodeContext *ctx) return err; /* get decoding parameters from header info */ - ctx->bit_alloc_params.fscod = hdr.fscod; + ctx->bit_alloc_params.sr_code = hdr.sr_code; ctx->acmod = hdr.acmod; cmixlev = gain_levels[clevs[hdr.cmixlev]]; surmixlev = gain_levels[slevs[hdr.surmixlev]]; ctx->dsurmod = hdr.dsurmod; ctx->lfeon = hdr.lfeon; - ctx->bit_alloc_params.halfratecod = hdr.halfratecod; + ctx->bit_alloc_params.sr_shift = hdr.sr_shift; ctx->sampling_rate = hdr.sample_rate; ctx->bit_rate = hdr.bit_rate; ctx->nchans = hdr.channels; @@ -947,10 +947,10 @@ static int ac3_parse_audio_block(AC3DecodeContext *ctx, int blk) /* bit allocation information */ if (get_bits1(gb)) { - ctx->bit_alloc_params.sdecay = ff_ac3_slow_decay_tab[get_bits(gb, 2)] >> ctx->bit_alloc_params.halfratecod; - ctx->bit_alloc_params.fdecay = ff_ac3_fast_decay_tab[get_bits(gb, 2)] >> ctx->bit_alloc_params.halfratecod; - ctx->bit_alloc_params.sgain = ff_ac3_slow_gain_tab[get_bits(gb, 2)]; - ctx->bit_alloc_params.dbknee = ff_ac3_db_per_bit_tab[get_bits(gb, 2)]; + ctx->bit_alloc_params.slow_decay = ff_ac3_slow_decay_tab[get_bits(gb, 2)] >> ctx->bit_alloc_params.sr_shift; + ctx->bit_alloc_params.fast_decay = ff_ac3_fast_decay_tab[get_bits(gb, 2)] >> ctx->bit_alloc_params.sr_shift; + ctx->bit_alloc_params.slow_gain = ff_ac3_slow_gain_tab[get_bits(gb, 2)]; + ctx->bit_alloc_params.db_per_bit = ff_ac3_db_per_bit_tab[get_bits(gb, 2)]; ctx->bit_alloc_params.floor = ff_ac3_floor_tab[get_bits(gb, 3)]; for(ch=!ctx->cplinu; ch<=ctx->nchans; ch++) { bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2); @@ -962,16 +962,16 @@ static int ac3_parse_audio_block(AC3DecodeContext *ctx, int blk) int csnr; csnr = (get_bits(gb, 6) - 15) << 4; for (ch = !ctx->cplinu; ch <= ctx->nchans; ch++) { /* snr offset and fast gain */ - ctx->snroffst[ch] = (csnr + get_bits(gb, 4)) << 2; - ctx->fgain[ch] = ff_ac3_fast_gain_tab[get_bits(gb, 3)]; + ctx->snr_offset[ch] = (csnr + get_bits(gb, 4)) << 2; + ctx->fast_gain[ch] = ff_ac3_fast_gain_tab[get_bits(gb, 3)]; } memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS); } /* coupling leak information */ if (ctx->cplinu && get_bits1(gb)) { - ctx->bit_alloc_params.cplfleak = get_bits(gb, 3); - ctx->bit_alloc_params.cplsleak = get_bits(gb, 3); + ctx->bit_alloc_params.cpl_fast_leak = get_bits(gb, 3); + ctx->bit_alloc_params.cpl_slow_leak = get_bits(gb, 3); bit_alloc_stages[CPL_CH] = FFMAX(bit_alloc_stages[CPL_CH], 2); } @@ -979,8 +979,8 @@ static int ac3_parse_audio_block(AC3DecodeContext *ctx, int blk) if (get_bits1(gb)) { /* delta bit allocation exists (strategy) */ for (ch = !ctx->cplinu; ch <= nfchans; ch++) { - ctx->deltbae[ch] = get_bits(gb, 2); - if (ctx->deltbae[ch] == DBA_RESERVED) { + ctx->dba_mode[ch] = get_bits(gb, 2); + if (ctx->dba_mode[ch] == DBA_RESERVED) { av_log(ctx->avctx, AV_LOG_ERROR, "delta bit allocation strategy reserved\n"); return -1; } @@ -988,18 +988,18 @@ static int ac3_parse_audio_block(AC3DecodeContext *ctx, int blk) } /* channel delta offset, len and bit allocation */ for (ch = !ctx->cplinu; ch <= nfchans; ch++) { - if (ctx->deltbae[ch] == DBA_NEW) { - ctx->deltnseg[ch] = get_bits(gb, 3); - for (seg = 0; seg <= ctx->deltnseg[ch]; seg++) { - ctx->deltoffst[ch][seg] = get_bits(gb, 5); - ctx->deltlen[ch][seg] = get_bits(gb, 4); - ctx->deltba[ch][seg] = get_bits(gb, 3); + if (ctx->dba_mode[ch] == DBA_NEW) { + ctx->dba_nsegs[ch] = get_bits(gb, 3); + for (seg = 0; seg <= ctx->dba_nsegs[ch]; seg++) { + ctx->dba_offsets[ch][seg] = get_bits(gb, 5); + ctx->dba_lengths[ch][seg] = get_bits(gb, 4); + ctx->dba_values[ch][seg] = get_bits(gb, 3); } } } } else if(blk == 0) { for(ch=0; ch<=ctx->nchans; ch++) { - ctx->deltbae[ch] = DBA_NONE; + ctx->dba_mode[ch] = DBA_NONE; } } @@ -1009,23 +1009,23 @@ static int ac3_parse_audio_block(AC3DecodeContext *ctx, int blk) /* Exponent mapping into PSD and PSD integration */ ff_ac3_bit_alloc_calc_psd(ctx->dexps[ch], ctx->startmant[ch], ctx->endmant[ch], - ctx->psd[ch], ctx->bndpsd[ch]); + ctx->psd[ch], ctx->band_psd[ch]); } if(bit_alloc_stages[ch] > 1) { /* Compute excitation function, Compute masking curve, and Apply delta bit allocation */ - ff_ac3_bit_alloc_calc_mask(&ctx->bit_alloc_params, ctx->bndpsd[ch], + ff_ac3_bit_alloc_calc_mask(&ctx->bit_alloc_params, ctx->band_psd[ch], ctx->startmant[ch], ctx->endmant[ch], - ctx->fgain[ch], (ch == ctx->lfe_ch), - ctx->deltbae[ch], ctx->deltnseg[ch], - ctx->deltoffst[ch], ctx->deltlen[ch], - ctx->deltba[ch], ctx->mask[ch]); + ctx->fast_gain[ch], (ch == ctx->lfe_ch), + ctx->dba_mode[ch], ctx->dba_nsegs[ch], + ctx->dba_offsets[ch], ctx->dba_lengths[ch], + ctx->dba_values[ch], ctx->mask[ch]); } if(bit_alloc_stages[ch] > 0) { /* Compute bit allocation */ ff_ac3_bit_alloc_calc_bap(ctx->mask[ch], ctx->psd[ch], ctx->startmant[ch], ctx->endmant[ch], - ctx->snroffst[ch], + ctx->snr_offset[ch], ctx->bit_alloc_params.floor, ctx->bap[ch]); } diff --git a/libavcodec/ac3enc.c b/libavcodec/ac3enc.c index d594905e68..07fc12c45c 100644 --- a/libavcodec/ac3enc.c +++ b/libavcodec/ac3enc.c @@ -42,9 +42,9 @@ typedef struct AC3EncodeContext { unsigned int frame_size; /* current frame size in words */ unsigned int bits_written; unsigned int samples_written; - int halfratecod; + int sr_shift; unsigned int frmsizecod; - unsigned int fscod; /* frequency */ + unsigned int sr_code; /* frequency */ unsigned int acmod; int lfe; unsigned int bsmod; @@ -53,11 +53,11 @@ typedef struct AC3EncodeContext { 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; @@ -438,7 +438,7 @@ static void bit_alloc_masking(AC3EncodeContext *s, 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; blknb_all_channels;ch++) { @@ -448,10 +448,10 @@ static void bit_alloc_masking(AC3EncodeContext *s, } 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_ac3_fast_gain_tab[s->fgaincod[ch]], + ff_ac3_fast_gain_tab[s->fast_gain_code[ch]], ch == s->lfe_channel, DBA_NONE, 0, NULL, NULL, NULL, mask[blk][ch]); @@ -464,12 +464,12 @@ static int bit_alloc(AC3EncodeContext *s, 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;imant4_cnt = 0; for(ch=0;chnb_all_channels;ch++) { ff_ac3_bit_alloc_calc_bap(mask[i][ch], psd[i][ch], 0, - s->nb_coefs[ch], snroffset, + s->nb_coefs[ch], snr_offset, s->bit_alloc.floor, bap[i][ch]); frame_bits += compute_mantissa_size(s, bap[i][ch], s->nb_coefs[ch]); @@ -486,7 +486,7 @@ static int bit_alloc(AC3EncodeContext *s, } #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; @@ -501,29 +501,29 @@ static int compute_bit_allocation(AC3EncodeContext *s, 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 }; /* 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;chnb_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_ac3_slow_decay_tab[s->sdecaycod] >> s->halfratecod; - s->bit_alloc.fdecay = ff_ac3_fast_decay_tab[s->fdecaycod] >> s->halfratecod; - s->bit_alloc.sgain = ff_ac3_slow_gain_tab[s->sgaincod]; - s->bit_alloc.dbknee = ff_ac3_db_per_bit_tab[s->dbkneecod]; - s->bit_alloc.floor = ff_ac3_floor_tab[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; @@ -568,43 +568,43 @@ static int compute_bit_allocation(AC3EncodeContext *s, /* 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) { + 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, -ab 384k for example!\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;chnb_all_channels;ch++) - s->fsnroffst[ch] = fsnroffst; + s->fine_snr_offset[ch] = fine_snr_offset; #if defined(DEBUG_BITALLOC) { int j; @@ -663,22 +663,22 @@ static int AC3_encode_init(AVCodecContext *avctx) return -1; found: s->sample_rate = freq; - s->halfratecod = i; - s->fscod = j; - s->bsid = 8 + s->halfratecod; + s->sr_shift = i; + s->sr_code = j; + s->bsid = 8 + s->sr_shift; s->bsmod = 0; /* complete main audio service */ /* bitrate & frame size */ bitrate /= 1000; for(i=0;i<19;i++) { - if ((ff_ac3_bitrate_tab[i] >> s->halfratecod) == bitrate) + if ((ff_ac3_bitrate_tab[i] >> s->sr_shift) == bitrate) break; } if (i == 19) return -1; s->bit_rate = bitrate; s->frmsizecod = i << 1; - s->frame_size_min = ff_ac3_frame_size_tab[s->frmsizecod][s->fscod]; + s->frame_size_min = ff_ac3_frame_size_tab[s->frmsizecod][s->sr_code]; s->bits_written = 0; s->samples_written = 0; s->frame_size = s->frame_size_min; @@ -695,7 +695,7 @@ static int AC3_encode_init(AVCodecContext *avctx) 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); @@ -718,7 +718,7 @@ static void output_frame_header(AC3EncodeContext *s, unsigned char *frame) 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, 2, s->sr_code); 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); @@ -900,20 +900,20 @@ static void output_audio_block(AC3EncodeContext *s, 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;chnb_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]); } }