diff options
Diffstat (limited to 'contrib/ffmpeg/libavcodec/flacenc.c')
| -rw-r--r-- | contrib/ffmpeg/libavcodec/flacenc.c | 1371 |
1 files changed, 0 insertions, 1371 deletions
diff --git a/contrib/ffmpeg/libavcodec/flacenc.c b/contrib/ffmpeg/libavcodec/flacenc.c deleted file mode 100644 index 9dd6c7eb8..000000000 --- a/contrib/ffmpeg/libavcodec/flacenc.c +++ /dev/null @@ -1,1371 +0,0 @@ -/** - * FLAC audio encoder - * Copyright (c) 2006 Justin Ruggles <jruggle@earthlink.net> - * - * 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 "avcodec.h" -#include "bitstream.h" -#include "crc.h" -#include "golomb.h" -#include "lls.h" - -#define FLAC_MAX_CH 8 -#define FLAC_MIN_BLOCKSIZE 16 -#define FLAC_MAX_BLOCKSIZE 65535 - -#define FLAC_SUBFRAME_CONSTANT 0 -#define FLAC_SUBFRAME_VERBATIM 1 -#define FLAC_SUBFRAME_FIXED 8 -#define FLAC_SUBFRAME_LPC 32 - -#define FLAC_CHMODE_NOT_STEREO 0 -#define FLAC_CHMODE_LEFT_RIGHT 1 -#define FLAC_CHMODE_LEFT_SIDE 8 -#define FLAC_CHMODE_RIGHT_SIDE 9 -#define FLAC_CHMODE_MID_SIDE 10 - -#define ORDER_METHOD_EST 0 -#define ORDER_METHOD_2LEVEL 1 -#define ORDER_METHOD_4LEVEL 2 -#define ORDER_METHOD_8LEVEL 3 -#define ORDER_METHOD_SEARCH 4 -#define ORDER_METHOD_LOG 5 - -#define FLAC_STREAMINFO_SIZE 34 - -#define MIN_LPC_ORDER 1 -#define MAX_LPC_ORDER 32 -#define MAX_FIXED_ORDER 4 -#define MAX_PARTITION_ORDER 8 -#define MAX_PARTITIONS (1 << MAX_PARTITION_ORDER) -#define MAX_LPC_PRECISION 15 -#define MAX_LPC_SHIFT 15 -#define MAX_RICE_PARAM 14 - -typedef struct CompressionOptions { - int compression_level; - int block_time_ms; - int use_lpc; - int lpc_coeff_precision; - int min_prediction_order; - int max_prediction_order; - int prediction_order_method; - int min_partition_order; - int max_partition_order; -} CompressionOptions; - -typedef struct RiceContext { - int porder; - int params[MAX_PARTITIONS]; -} RiceContext; - -typedef struct FlacSubframe { - int type; - int type_code; - int obits; - int order; - int32_t coefs[MAX_LPC_ORDER]; - int shift; - RiceContext rc; - int32_t samples[FLAC_MAX_BLOCKSIZE]; - int32_t residual[FLAC_MAX_BLOCKSIZE]; -} FlacSubframe; - -typedef struct FlacFrame { - FlacSubframe subframes[FLAC_MAX_CH]; - int blocksize; - int bs_code[2]; - uint8_t crc8; - int ch_mode; -} FlacFrame; - -typedef struct FlacEncodeContext { - PutBitContext pb; - int channels; - int ch_code; - int samplerate; - int sr_code[2]; - int blocksize; - int max_framesize; - uint32_t frame_count; - FlacFrame frame; - CompressionOptions options; - AVCodecContext *avctx; -} FlacEncodeContext; - -static const int flac_samplerates[16] = { - 0, 0, 0, 0, - 8000, 16000, 22050, 24000, 32000, 44100, 48000, 96000, - 0, 0, 0, 0 -}; - -static const int flac_blocksizes[16] = { - 0, - 192, - 576, 1152, 2304, 4608, - 0, 0, - 256, 512, 1024, 2048, 4096, 8192, 16384, 32768 -}; - -/** - * Writes streaminfo metadata block to byte array - */ -static void write_streaminfo(FlacEncodeContext *s, uint8_t *header) -{ - PutBitContext pb; - - memset(header, 0, FLAC_STREAMINFO_SIZE); - init_put_bits(&pb, header, FLAC_STREAMINFO_SIZE); - - /* streaminfo metadata block */ - put_bits(&pb, 16, s->blocksize); - put_bits(&pb, 16, s->blocksize); - put_bits(&pb, 24, 0); - put_bits(&pb, 24, s->max_framesize); - put_bits(&pb, 20, s->samplerate); - put_bits(&pb, 3, s->channels-1); - put_bits(&pb, 5, 15); /* bits per sample - 1 */ - flush_put_bits(&pb); - /* total samples = 0 */ - /* MD5 signature = 0 */ -} - -/** - * Sets blocksize based on samplerate - * Chooses the closest predefined blocksize >= BLOCK_TIME_MS milliseconds - */ -static int select_blocksize(int samplerate, int block_time_ms) -{ - int i; - int target; - int blocksize; - - assert(samplerate > 0); - blocksize = flac_blocksizes[1]; - target = (samplerate * block_time_ms) / 1000; - for(i=0; i<16; i++) { - if(target >= flac_blocksizes[i] && flac_blocksizes[i] > blocksize) { - blocksize = flac_blocksizes[i]; - } - } - return blocksize; -} - -static int flac_encode_init(AVCodecContext *avctx) -{ - int freq = avctx->sample_rate; - int channels = avctx->channels; - FlacEncodeContext *s = avctx->priv_data; - int i, level; - uint8_t *streaminfo; - - s->avctx = avctx; - - if(avctx->sample_fmt != SAMPLE_FMT_S16) { - return -1; - } - - if(channels < 1 || channels > FLAC_MAX_CH) { - return -1; - } - s->channels = channels; - s->ch_code = s->channels-1; - - /* find samplerate in table */ - if(freq < 1) - return -1; - for(i=4; i<12; i++) { - if(freq == flac_samplerates[i]) { - s->samplerate = flac_samplerates[i]; - s->sr_code[0] = i; - s->sr_code[1] = 0; - break; - } - } - /* if not in table, samplerate is non-standard */ - if(i == 12) { - if(freq % 1000 == 0 && freq < 255000) { - s->sr_code[0] = 12; - s->sr_code[1] = freq / 1000; - } else if(freq % 10 == 0 && freq < 655350) { - s->sr_code[0] = 14; - s->sr_code[1] = freq / 10; - } else if(freq < 65535) { - s->sr_code[0] = 13; - s->sr_code[1] = freq; - } else { - return -1; - } - s->samplerate = freq; - } - - /* set compression option defaults based on avctx->compression_level */ - if(avctx->compression_level < 0) { - s->options.compression_level = 5; - } else { - s->options.compression_level = avctx->compression_level; - } - av_log(avctx, AV_LOG_DEBUG, " compression: %d\n", s->options.compression_level); - - level= s->options.compression_level; - if(level > 12) { - av_log(avctx, AV_LOG_ERROR, "invalid compression level: %d\n", - s->options.compression_level); - return -1; - } - - s->options.block_time_ms = ((int[]){ 27, 27, 27,105,105,105,105,105,105,105,105,105,105})[level]; - s->options.use_lpc = ((int[]){ 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1})[level]; - s->options.min_prediction_order= ((int[]){ 2, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1})[level]; - s->options.max_prediction_order= ((int[]){ 3, 4, 4, 6, 8, 8, 8, 8, 12, 12, 12, 32, 32})[level]; - s->options.prediction_order_method = ((int[]){ ORDER_METHOD_EST, ORDER_METHOD_EST, ORDER_METHOD_EST, - ORDER_METHOD_EST, ORDER_METHOD_EST, ORDER_METHOD_EST, - ORDER_METHOD_4LEVEL, ORDER_METHOD_LOG, ORDER_METHOD_4LEVEL, - ORDER_METHOD_LOG, ORDER_METHOD_SEARCH, ORDER_METHOD_LOG, - ORDER_METHOD_SEARCH})[level]; - s->options.min_partition_order = ((int[]){ 2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0})[level]; - s->options.max_partition_order = ((int[]){ 2, 2, 3, 3, 3, 8, 8, 8, 8, 8, 8, 8, 8})[level]; - - /* set compression option overrides from AVCodecContext */ - if(avctx->use_lpc >= 0) { - s->options.use_lpc = av_clip(avctx->use_lpc, 0, 11); - } - if(s->options.use_lpc == 1) - av_log(avctx, AV_LOG_DEBUG, " use lpc: Levinson-Durbin recursion with Welch window\n"); - else if(s->options.use_lpc > 1) - av_log(avctx, AV_LOG_DEBUG, " use lpc: Cholesky factorization\n"); - - if(avctx->min_prediction_order >= 0) { - if(s->options.use_lpc) { - if(avctx->min_prediction_order < MIN_LPC_ORDER || - avctx->min_prediction_order > MAX_LPC_ORDER) { - av_log(avctx, AV_LOG_ERROR, "invalid min prediction order: %d\n", - avctx->min_prediction_order); - return -1; - } - } else { - if(avctx->min_prediction_order > MAX_FIXED_ORDER) { - av_log(avctx, AV_LOG_ERROR, "invalid min prediction order: %d\n", - avctx->min_prediction_order); - return -1; - } - } - s->options.min_prediction_order = avctx->min_prediction_order; - } - if(avctx->max_prediction_order >= 0) { - if(s->options.use_lpc) { - if(avctx->max_prediction_order < MIN_LPC_ORDER || - avctx->max_prediction_order > MAX_LPC_ORDER) { - av_log(avctx, AV_LOG_ERROR, "invalid max prediction order: %d\n", - avctx->max_prediction_order); - return -1; - } - } else { - if(avctx->max_prediction_order > MAX_FIXED_ORDER) { - av_log(avctx, AV_LOG_ERROR, "invalid max prediction order: %d\n", - avctx->max_prediction_order); - return -1; - } - } - s->options.max_prediction_order = avctx->max_prediction_order; - } - if(s->options.max_prediction_order < s->options.min_prediction_order) { - av_log(avctx, AV_LOG_ERROR, "invalid prediction orders: min=%d max=%d\n", - s->options.min_prediction_order, s->options.max_prediction_order); - return -1; - } - av_log(avctx, AV_LOG_DEBUG, " prediction order: %d, %d\n", - s->options.min_prediction_order, s->options.max_prediction_order); - - if(avctx->prediction_order_method >= 0) { - if(avctx->prediction_order_method > ORDER_METHOD_LOG) { - av_log(avctx, AV_LOG_ERROR, "invalid prediction order method: %d\n", - avctx->prediction_order_method); - return -1; - } - s->options.prediction_order_method = avctx->prediction_order_method; - } - switch(s->options.prediction_order_method) { - case ORDER_METHOD_EST: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n", - "estimate"); break; - case ORDER_METHOD_2LEVEL: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n", - "2-level"); break; - case ORDER_METHOD_4LEVEL: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n", - "4-level"); break; - case ORDER_METHOD_8LEVEL: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n", - "8-level"); break; - case ORDER_METHOD_SEARCH: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n", - "full search"); break; - case ORDER_METHOD_LOG: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n", - "log search"); break; - } - - if(avctx->min_partition_order >= 0) { - if(avctx->min_partition_order > MAX_PARTITION_ORDER) { - av_log(avctx, AV_LOG_ERROR, "invalid min partition order: %d\n", - avctx->min_partition_order); - return -1; - } - s->options.min_partition_order = avctx->min_partition_order; - } - if(avctx->max_partition_order >= 0) { - if(avctx->max_partition_order > MAX_PARTITION_ORDER) { - av_log(avctx, AV_LOG_ERROR, "invalid max partition order: %d\n", - avctx->max_partition_order); - return -1; - } - s->options.max_partition_order = avctx->max_partition_order; - } - if(s->options.max_partition_order < s->options.min_partition_order) { - av_log(avctx, AV_LOG_ERROR, "invalid partition orders: min=%d max=%d\n", - s->options.min_partition_order, s->options.max_partition_order); - return -1; - } - av_log(avctx, AV_LOG_DEBUG, " partition order: %d, %d\n", - s->options.min_partition_order, s->options.max_partition_order); - - if(avctx->frame_size > 0) { - if(avctx->frame_size < FLAC_MIN_BLOCKSIZE || - avctx->frame_size > FLAC_MAX_BLOCKSIZE) { - av_log(avctx, AV_LOG_ERROR, "invalid block size: %d\n", - avctx->frame_size); - return -1; - } - s->blocksize = avctx->frame_size; - } else { - s->blocksize = select_blocksize(s->samplerate, s->options.block_time_ms); - avctx->frame_size = s->blocksize; - } - av_log(avctx, AV_LOG_DEBUG, " block size: %d\n", s->blocksize); - - /* set LPC precision */ - if(avctx->lpc_coeff_precision > 0) { - if(avctx->lpc_coeff_precision > MAX_LPC_PRECISION) { - av_log(avctx, AV_LOG_ERROR, "invalid lpc coeff precision: %d\n", - avctx->lpc_coeff_precision); - return -1; - } - s->options.lpc_coeff_precision = avctx->lpc_coeff_precision; - } else { - /* select LPC precision based on block size */ - if( s->blocksize <= 192) s->options.lpc_coeff_precision = 7; - else if(s->blocksize <= 384) s->options.lpc_coeff_precision = 8; - else if(s->blocksize <= 576) s->options.lpc_coeff_precision = 9; - else if(s->blocksize <= 1152) s->options.lpc_coeff_precision = 10; - else if(s->blocksize <= 2304) s->options.lpc_coeff_precision = 11; - else if(s->blocksize <= 4608) s->options.lpc_coeff_precision = 12; - else if(s->blocksize <= 8192) s->options.lpc_coeff_precision = 13; - else if(s->blocksize <= 16384) s->options.lpc_coeff_precision = 14; - else s->options.lpc_coeff_precision = 15; - } - av_log(avctx, AV_LOG_DEBUG, " lpc precision: %d\n", - s->options.lpc_coeff_precision); - - /* set maximum encoded frame size in verbatim mode */ - if(s->channels == 2) { - s->max_framesize = 14 + ((s->blocksize * 33 + 7) >> 3); - } else { - s->max_framesize = 14 + (s->blocksize * s->channels * 2); - } - - streaminfo = av_malloc(FLAC_STREAMINFO_SIZE); - write_streaminfo(s, streaminfo); - avctx->extradata = streaminfo; - avctx->extradata_size = FLAC_STREAMINFO_SIZE; - - s->frame_count = 0; - - avctx->coded_frame = avcodec_alloc_frame(); - avctx->coded_frame->key_frame = 1; - - return 0; -} - -static void init_frame(FlacEncodeContext *s) -{ - int i, ch; - FlacFrame *frame; - - frame = &s->frame; - - for(i=0; i<16; i++) { - if(s->blocksize == flac_blocksizes[i]) { - frame->blocksize = flac_blocksizes[i]; - frame->bs_code[0] = i; - frame->bs_code[1] = 0; - break; - } - } - if(i == 16) { - frame->blocksize = s->blocksize; - if(frame->blocksize <= 256) { - frame->bs_code[0] = 6; - frame->bs_code[1] = frame->blocksize-1; - } else { - frame->bs_code[0] = 7; - frame->bs_code[1] = frame->blocksize-1; - } - } - - for(ch=0; ch<s->channels; ch++) { - frame->subframes[ch].obits = 16; - } -} - -/** - * Copy channel-interleaved input samples into separate subframes - */ -static void copy_samples(FlacEncodeContext *s, int16_t *samples) -{ - int i, j, ch; - FlacFrame *frame; - - frame = &s->frame; - for(i=0,j=0; i<frame->blocksize; i++) { - for(ch=0; ch<s->channels; ch++,j++) { - frame->subframes[ch].samples[i] = samples[j]; - } - } -} - - -#define rice_encode_count(sum, n, k) (((n)*((k)+1))+((sum-(n>>1))>>(k))) - -static int find_optimal_param(uint32_t sum, int n) -{ - int k, k_opt; - uint32_t nbits[MAX_RICE_PARAM+1]; - - k_opt = 0; - nbits[0] = UINT32_MAX; - for(k=0; k<=MAX_RICE_PARAM; k++) { - nbits[k] = rice_encode_count(sum, n, k); - if(nbits[k] < nbits[k_opt]) { - k_opt = k; - } - } - return k_opt; -} - -static uint32_t calc_optimal_rice_params(RiceContext *rc, int porder, - uint32_t *sums, int n, int pred_order) -{ - int i; - int k, cnt, part; - uint32_t all_bits; - - part = (1 << porder); - all_bits = 0; - - cnt = (n >> porder) - pred_order; - for(i=0; i<part; i++) { - if(i == 1) cnt = (n >> porder); - k = find_optimal_param(sums[i], cnt); - rc->params[i] = k; - all_bits += rice_encode_count(sums[i], cnt, k); - } - all_bits += (4 * part); - - rc->porder = porder; - - return all_bits; -} - -static void calc_sums(int pmin, int pmax, uint32_t *data, int n, int pred_order, - uint32_t sums[][MAX_PARTITIONS]) -{ - int i, j; - int parts; - uint32_t *res, *res_end; - - /* sums for highest level */ - parts = (1 << pmax); - res = &data[pred_order]; - res_end = &data[n >> pmax]; - for(i=0; i<parts; i++) { - sums[pmax][i] = 0; - while(res < res_end){ - sums[pmax][i] += *(res++); - } - res_end+= n >> pmax; - } - /* sums for lower levels */ - for(i=pmax-1; i>=pmin; i--) { - parts = (1 << i); - for(j=0; j<parts; j++) { - sums[i][j] = sums[i+1][2*j] + sums[i+1][2*j+1]; - } - } -} - -static uint32_t calc_rice_params(RiceContext *rc, int pmin, int pmax, - int32_t *data, int n, int pred_order) -{ - int i; - uint32_t bits[MAX_PARTITION_ORDER+1]; - int opt_porder; - RiceContext tmp_rc; - uint32_t *udata; - uint32_t sums[MAX_PARTITION_ORDER+1][MAX_PARTITIONS]; - - assert(pmin >= 0 && pmin <= MAX_PARTITION_ORDER); - assert(pmax >= 0 && pmax <= MAX_PARTITION_ORDER); - assert(pmin <= pmax); - - udata = av_malloc(n * sizeof(uint32_t)); - for(i=0; i<n; i++) { - udata[i] = (2*data[i]) ^ (data[i]>>31); - } - - calc_sums(pmin, pmax, udata, n, pred_order, sums); - - opt_porder = pmin; - bits[pmin] = UINT32_MAX; - for(i=pmin; i<=pmax; i++) { - bits[i] = calc_optimal_rice_params(&tmp_rc, i, sums[i], n, pred_order); - if(bits[i] <= bits[opt_porder]) { - opt_porder = i; - *rc= tmp_rc; - } - } - - av_freep(&udata); - return bits[opt_porder]; -} - -static int get_max_p_order(int max_porder, int n, int order) -{ - int porder = FFMIN(max_porder, av_log2(n^(n-1))); - if(order > 0) - porder = FFMIN(porder, av_log2(n/order)); - return porder; -} - -static uint32_t calc_rice_params_fixed(RiceContext *rc, int pmin, int pmax, - int32_t *data, int n, int pred_order, - int bps) -{ - uint32_t bits; - pmin = get_max_p_order(pmin, n, pred_order); - pmax = get_max_p_order(pmax, n, pred_order); - bits = pred_order*bps + 6; - bits += calc_rice_params(rc, pmin, pmax, data, n, pred_order); - return bits; -} - -static uint32_t calc_rice_params_lpc(RiceContext *rc, int pmin, int pmax, - int32_t *data, int n, int pred_order, - int bps, int precision) -{ - uint32_t bits; - pmin = get_max_p_order(pmin, n, pred_order); - pmax = get_max_p_order(pmax, n, pred_order); - bits = pred_order*bps + 4 + 5 + pred_order*precision + 6; - bits += calc_rice_params(rc, pmin, pmax, data, n, pred_order); - return bits; -} - -/** - * Apply Welch window function to audio block - */ -static void apply_welch_window(const int32_t *data, int len, double *w_data) -{ - int i, n2; - double w; - double c; - - n2 = (len >> 1); - c = 2.0 / (len - 1.0); - for(i=0; i<n2; i++) { - w = c - i - 1.0; - w = 1.0 - (w * w); - w_data[i] = data[i] * w; - w_data[len-1-i] = data[len-1-i] * w; - } -} - -/** - * Calculates autocorrelation data from audio samples - * A Welch window function is applied before calculation. - */ -static void compute_autocorr(const int32_t *data, int len, int lag, - double *autoc) -{ - int i, lag_ptr; - double tmp[len + lag]; - double *data1= tmp + lag; - - apply_welch_window(data, len, data1); - - for(i=0; i<lag; i++){ - autoc[i] = 1.0; - data1[i-lag]= 0.0; - } - - for(i=0; i<len; i++){ - for(lag_ptr= i-lag; lag_ptr<=i; lag_ptr++){ - autoc[i-lag_ptr] += data1[i] * data1[lag_ptr]; - } - } -} - -/** - * Levinson-Durbin recursion. - * Produces LPC coefficients from autocorrelation data. - */ -static void compute_lpc_coefs(const double *autoc, int max_order, - double lpc[][MAX_LPC_ORDER], double *ref) -{ - int i, j, i2; - double r, err, tmp; - double lpc_tmp[MAX_LPC_ORDER]; - - for(i=0; i<max_order; i++) lpc_tmp[i] = 0; - err = autoc[0]; - - for(i=0; i<max_order; i++) { - r = -autoc[i+1]; - for(j=0; j<i; j++) { - r -= lpc_tmp[j] * autoc[i-j]; - } - r /= err; - ref[i] = fabs(r); - - err *= 1.0 - (r * r); - - i2 = (i >> 1); - lpc_tmp[i] = r; - for(j=0; j<i2; j++) { - tmp = lpc_tmp[j]; - lpc_tmp[j] += r * lpc_tmp[i-1-j]; - lpc_tmp[i-1-j] += r * tmp; - } - if(i & 1) { - lpc_tmp[j] += lpc_tmp[j] * r; - } - - for(j=0; j<=i; j++) { - lpc[i][j] = -lpc_tmp[j]; - } - } -} - -/** - * Quantize LPC coefficients - */ -static void quantize_lpc_coefs(double *lpc_in, int order, int precision, - int32_t *lpc_out, int *shift) -{ - int i; - double cmax, error; - int32_t qmax; - int sh; - - /* define maximum levels */ - qmax = (1 << (precision - 1)) - 1; - - /* find maximum coefficient value */ - cmax = 0.0; - for(i=0; i<order; i++) { - cmax= FFMAX(cmax, fabs(lpc_in[i])); - } - - /* if maximum value quantizes to zero, return all zeros */ - if(cmax * (1 << MAX_LPC_SHIFT) < 1.0) { - *shift = 0; - memset(lpc_out, 0, sizeof(int32_t) * order); - return; - } - - /* calculate level shift which scales max coeff to available bits */ - sh = MAX_LPC_SHIFT; - while((cmax * (1 << sh) > qmax) && (sh > 0)) { - sh--; - } - - /* since negative shift values are unsupported in decoder, scale down - coefficients instead */ - if(sh == 0 && cmax > qmax) { - double scale = ((double)qmax) / cmax; - for(i=0; i<order; i++) { - lpc_in[i] *= scale; - } - } - - /* output quantized coefficients and level shift */ - error=0; - for(i=0; i<order; i++) { - error += lpc_in[i] * (1 << sh); - lpc_out[i] = av_clip(lrintf(error), -qmax, qmax); - error -= lpc_out[i]; - } - *shift = sh; -} - -static int estimate_best_order(double *ref, int max_order) -{ - int i, est; - - est = 1; - for(i=max_order-1; i>=0; i--) { - if(ref[i] > 0.10) { - est = i+1; - break; - } - } - return est; -} - -/** - * Calculate LPC coefficients for multiple orders - */ -static int lpc_calc_coefs(const int32_t *samples, int blocksize, int max_order, - int precision, int32_t coefs[][MAX_LPC_ORDER], - int *shift, int use_lpc, int omethod) -{ - double autoc[MAX_LPC_ORDER+1]; - double ref[MAX_LPC_ORDER]; - double lpc[MAX_LPC_ORDER][MAX_LPC_ORDER]; - int i, j, pass; - int opt_order; - - assert(max_order >= MIN_LPC_ORDER && max_order <= MAX_LPC_ORDER); - - if(use_lpc == 1){ - compute_autocorr(samples, blocksize, max_order+1, autoc); - - compute_lpc_coefs(autoc, max_order, lpc, ref); - }else{ - LLSModel m[2]; - double var[MAX_LPC_ORDER+1], eval, weight; - - for(pass=0; pass<use_lpc-1; pass++){ - av_init_lls(&m[pass&1], max_order); - - weight=0; - for(i=max_order; i<blocksize; i++){ - for(j=0; j<=max_order; j++) - var[j]= samples[i-j]; - - if(pass){ - eval= av_evaluate_lls(&m[(pass-1)&1], var+1, max_order-1); - eval= (512>>pass) + fabs(eval - var[0]); - for(j=0; j<=max_order; j++) - var[j]/= sqrt(eval); - weight += 1/eval; - }else - weight++; - - av_update_lls(&m[pass&1], var, 1.0); - } - av_solve_lls(&m[pass&1], 0.001, 0); - } - - for(i=0; i<max_order; i++){ - for(j=0; j<max_order; j++) - lpc[i][j]= m[(pass-1)&1].coeff[i][j]; - ref[i]= sqrt(m[(pass-1)&1].variance[i] / weight) * (blocksize - max_order) / 4000; - } - for(i=max_order-1; i>0; i--) - ref[i] = ref[i-1] - ref[i]; - } - opt_order = max_order; - - if(omethod == ORDER_METHOD_EST) { - opt_order = estimate_best_order(ref, max_order); - i = opt_order-1; - quantize_lpc_coefs(lpc[i], i+1, precision, coefs[i], &shift[i]); - } else { - for(i=0; i<max_order; i++) { - quantize_lpc_coefs(lpc[i], i+1, precision, coefs[i], &shift[i]); - } - } - - return opt_order; -} - - -static void encode_residual_verbatim(int32_t *res, int32_t *smp, int n) -{ - assert(n > 0); - memcpy(res, smp, n * sizeof(int32_t)); -} - -static void encode_residual_fixed(int32_t *res, const int32_t *smp, int n, - int order) -{ - int i; - - for(i=0; i<order; i++) { - res[i] = smp[i]; - } - - if(order==0){ - for(i=order; i<n; i++) - res[i]= smp[i]; - }else if(order==1){ - for(i=order; i<n; i++) - res[i]= smp[i] - smp[i-1]; - }else if(order==2){ - for(i=order; i<n; i++) - res[i]= smp[i] - 2*smp[i-1] + smp[i-2]; - }else if(order==3){ - for(i=order; i<n; i++) - res[i]= smp[i] - 3*smp[i-1] + 3*smp[i-2] - smp[i-3]; - }else{ - for(i=order; i<n; i++) - res[i]= smp[i] - 4*smp[i-1] + 6*smp[i-2] - 4*smp[i-3] + smp[i-4]; - } -} - -static void encode_residual_lpc(int32_t *res, const int32_t *smp, int n, - int order, const int32_t *coefs, int shift) -{ - int i, j; - int32_t pred; - - for(i=0; i<order; i++) { - res[i] = smp[i]; - } - for(i=order; i<n; i++) { - pred = 0; - for(j=0; j<order; j++) { - pred += coefs[j] * smp[i-j-1]; - } - res[i] = smp[i] - (pred >> shift); - } -} - -static int encode_residual(FlacEncodeContext *ctx, int ch) -{ - int i, n; - int min_order, max_order, opt_order, precision, omethod; - int min_porder, max_porder; - FlacFrame *frame; - FlacSubframe *sub; - int32_t coefs[MAX_LPC_ORDER][MAX_LPC_ORDER]; - int shift[MAX_LPC_ORDER]; - int32_t *res, *smp; - - frame = &ctx->frame; - sub = &frame->subframes[ch]; - res = sub->residual; - smp = sub->samples; - n = frame->blocksize; - - /* CONSTANT */ - for(i=1; i<n; i++) { - if(smp[i] != smp[0]) break; - } - if(i == n) { - sub->type = sub->type_code = FLAC_SUBFRAME_CONSTANT; - res[0] = smp[0]; - return sub->obits; - } - - /* VERBATIM */ - if(n < 5) { - sub->type = sub->type_code = FLAC_SUBFRAME_VERBATIM; - encode_residual_verbatim(res, smp, n); - return sub->obits * n; - } - - min_order = ctx->options.min_prediction_order; - max_order = ctx->options.max_prediction_order; - min_porder = ctx->options.min_partition_order; - max_porder = ctx->options.max_partition_order; - precision = ctx->options.lpc_coeff_precision; - omethod = ctx->options.prediction_order_method; - - /* FIXED */ - if(!ctx->options.use_lpc || max_order == 0 || (n <= max_order)) { - uint32_t bits[MAX_FIXED_ORDER+1]; - if(max_order > MAX_FIXED_ORDER) max_order = MAX_FIXED_ORDER; - opt_order = 0; - bits[0] = UINT32_MAX; - for(i=min_order; i<=max_order; i++) { - encode_residual_fixed(res, smp, n, i); - bits[i] = calc_rice_params_fixed(&sub->rc, min_porder, max_porder, res, - n, i, sub->obits); - if(bits[i] < bits[opt_order]) { - opt_order = i; - } - } - sub->order = opt_order; - sub->type = FLAC_SUBFRAME_FIXED; - sub->type_code = sub->type | sub->order; - if(sub->order != max_order) { - encode_residual_fixed(res, smp, n, sub->order); - return calc_rice_params_fixed(&sub->rc, min_porder, max_porder, res, n, - sub->order, sub->obits); - } - return bits[sub->order]; - } - - /* LPC */ - opt_order = lpc_calc_coefs(smp, n, max_order, precision, coefs, shift, ctx->options.use_lpc, omethod); - - if(omethod == ORDER_METHOD_2LEVEL || - omethod == ORDER_METHOD_4LEVEL || - omethod == ORDER_METHOD_8LEVEL) { - int levels = 1 << omethod; - uint32_t bits[levels]; - int order; - int opt_index = levels-1; - opt_order = max_order-1; - bits[opt_index] = UINT32_MAX; - for(i=levels-1; i>=0; i--) { - order = min_order + (((max_order-min_order+1) * (i+1)) / levels)-1; - if(order < 0) order = 0; - encode_residual_lpc(res, smp, n, order+1, coefs[order], shift[order]); - bits[i] = calc_rice_params_lpc(&sub->rc, min_porder, max_porder, - res, n, order+1, sub->obits, precision); - if(bits[i] < bits[opt_index]) { - opt_index = i; - opt_order = order; - } - } - opt_order++; - } else if(omethod == ORDER_METHOD_SEARCH) { - // brute-force optimal order search - uint32_t bits[MAX_LPC_ORDER]; - opt_order = 0; - bits[0] = UINT32_MAX; - for(i=min_order-1; i<max_order; i++) { - encode_residual_lpc(res, smp, n, i+1, coefs[i], shift[i]); - bits[i] = calc_rice_params_lpc(&sub->rc, min_porder, max_porder, - res, n, i+1, sub->obits, precision); - if(bits[i] < bits[opt_order]) { - opt_order = i; - } - } - opt_order++; - } else if(omethod == ORDER_METHOD_LOG) { - uint32_t bits[MAX_LPC_ORDER]; - int step; - - opt_order= min_order - 1 + (max_order-min_order)/3; - memset(bits, -1, sizeof(bits)); - - for(step=16 ;step; step>>=1){ - int last= opt_order; - for(i=last-step; i<=last+step; i+= step){ - if(i<min_order-1 || i>=max_order || bits[i] < UINT32_MAX) - continue; - encode_residual_lpc(res, smp, n, i+1, coefs[i], shift[i]); - bits[i] = calc_rice_params_lpc(&sub->rc, min_porder, max_porder, - res, n, i+1, sub->obits, precision); - if(bits[i] < bits[opt_order]) - opt_order= i; - } - } - opt_order++; - } - - sub->order = opt_order; - sub->type = FLAC_SUBFRAME_LPC; - sub->type_code = sub->type | (sub->order-1); - sub->shift = shift[sub->order-1]; - for(i=0; i<sub->order; i++) { - sub->coefs[i] = coefs[sub->order-1][i]; - } - encode_residual_lpc(res, smp, n, sub->order, sub->coefs, sub->shift); - return calc_rice_params_lpc(&sub->rc, min_porder, max_porder, res, n, sub->order, - sub->obits, precision); -} - -static int encode_residual_v(FlacEncodeContext *ctx, int ch) -{ - int i, n; - FlacFrame *frame; - FlacSubframe *sub; - int32_t *res, *smp; - - frame = &ctx->frame; - sub = &frame->subframes[ch]; - res = sub->residual; - smp = sub->samples; - n = frame->blocksize; - - /* CONSTANT */ - for(i=1; i<n; i++) { - if(smp[i] != smp[0]) break; - } - if(i == n) { - sub->type = sub->type_code = FLAC_SUBFRAME_CONSTANT; - res[0] = smp[0]; - return sub->obits; - } - - /* VERBATIM */ - sub->type = sub->type_code = FLAC_SUBFRAME_VERBATIM; - encode_residual_verbatim(res, smp, n); - return sub->obits * n; -} - -static int estimate_stereo_mode(int32_t *left_ch, int32_t *right_ch, int n) -{ - int i, best; - int32_t lt, rt; - uint64_t sum[4]; - uint64_t score[4]; - int k; - - /* calculate sum of 2nd order residual for each channel */ - sum[0] = sum[1] = sum[2] = sum[3] = 0; - for(i=2; i<n; i++) { - lt = left_ch[i] - 2*left_ch[i-1] + left_ch[i-2]; - rt = right_ch[i] - 2*right_ch[i-1] + right_ch[i-2]; - sum[2] += FFABS((lt + rt) >> 1); - sum[3] += FFABS(lt - rt); - sum[0] += FFABS(lt); - sum[1] += FFABS(rt); - } - /* estimate bit counts */ - for(i=0; i<4; i++) { - k = find_optimal_param(2*sum[i], n); - sum[i] = rice_encode_count(2*sum[i], n, k); - } - - /* calculate score for each mode */ - score[0] = sum[0] + sum[1]; - score[1] = sum[0] + sum[3]; - score[2] = sum[1] + sum[3]; - score[3] = sum[2] + sum[3]; - - /* return mode with lowest score */ - best = 0; - for(i=1; i<4; i++) { - if(score[i] < score[best]) { - best = i; - } - } - if(best == 0) { - return FLAC_CHMODE_LEFT_RIGHT; - } else if(best == 1) { - return FLAC_CHMODE_LEFT_SIDE; - } else if(best == 2) { - return FLAC_CHMODE_RIGHT_SIDE; - } else { - return FLAC_CHMODE_MID_SIDE; - } -} - -/** - * Perform stereo channel decorrelation - */ -static void channel_decorrelation(FlacEncodeContext *ctx) -{ - FlacFrame *frame; - int32_t *left, *right; - int i, n; - - frame = &ctx->frame; - n = frame->blocksize; - left = frame->subframes[0].samples; - right = frame->subframes[1].samples; - - if(ctx->channels != 2) { - frame->ch_mode = FLAC_CHMODE_NOT_STEREO; - return; - } - - frame->ch_mode = estimate_stereo_mode(left, right, n); - - /* perform decorrelation and adjust bits-per-sample */ - if(frame->ch_mode == FLAC_CHMODE_LEFT_RIGHT) { - return; - } - if(frame->ch_mode == FLAC_CHMODE_MID_SIDE) { - int32_t tmp; - for(i=0; i<n; i++) { - tmp = left[i]; - left[i] = (tmp + right[i]) >> 1; - right[i] = tmp - right[i]; - } - frame->subframes[1].obits++; - } else if(frame->ch_mode == FLAC_CHMODE_LEFT_SIDE) { - for(i=0; i<n; i++) { - right[i] = left[i] - right[i]; - } - frame->subframes[1].obits++; - } else { - for(i=0; i<n; i++) { - left[i] -= right[i]; - } - frame->subframes[0].obits++; - } -} - -static void put_sbits(PutBitContext *pb, int bits, int32_t val) -{ - assert(bits >= 0 && bits <= 31); - - put_bits(pb, bits, val & ((1<<bits)-1)); -} - -static void write_utf8(PutBitContext *pb, uint32_t val) -{ - uint8_t tmp; - PUT_UTF8(val, tmp, put_bits(pb, 8, tmp);) -} - -static void output_frame_header(FlacEncodeContext *s) -{ - FlacFrame *frame; - int crc; - - frame = &s->frame; - - put_bits(&s->pb, 16, 0xFFF8); - put_bits(&s->pb, 4, frame->bs_code[0]); - put_bits(&s->pb, 4, s->sr_code[0]); - if(frame->ch_mode == FLAC_CHMODE_NOT_STEREO) { - put_bits(&s->pb, 4, s->ch_code); - } else { - put_bits(&s->pb, 4, frame->ch_mode); - } - put_bits(&s->pb, 3, 4); /* bits-per-sample code */ - put_bits(&s->pb, 1, 0); - write_utf8(&s->pb, s->frame_count); - if(frame->bs_code[0] == 6) { - put_bits(&s->pb, 8, frame->bs_code[1]); - } else if(frame->bs_code[0] == 7) { - put_bits(&s->pb, 16, frame->bs_code[1]); - } - if(s->sr_code[0] == 12) { - put_bits(&s->pb, 8, s->sr_code[1]); - } else if(s->sr_code[0] > 12) { - put_bits(&s->pb, 16, s->sr_code[1]); - } - flush_put_bits(&s->pb); - crc = av_crc(av_crc07, 0, s->pb.buf, put_bits_count(&s->pb)>>3); - put_bits(&s->pb, 8, crc); -} - -static void output_subframe_constant(FlacEncodeContext *s, int ch) -{ - FlacSubframe *sub; - int32_t res; - - sub = &s->frame.subframes[ch]; - res = sub->residual[0]; - put_sbits(&s->pb, sub->obits, res); -} - -static void output_subframe_verbatim(FlacEncodeContext *s, int ch) -{ - int i; - FlacFrame *frame; - FlacSubframe *sub; - int32_t res; - - frame = &s->frame; - sub = &frame->subframes[ch]; - - for(i=0; i<frame->blocksize; i++) { - res = sub->residual[i]; - put_sbits(&s->pb, sub->obits, res); - } -} - -static void output_residual(FlacEncodeContext *ctx, int ch) -{ - int i, j, p, n, parts; - int k, porder, psize, res_cnt; - FlacFrame *frame; - FlacSubframe *sub; - int32_t *res; - - frame = &ctx->frame; - sub = &frame->subframes[ch]; - res = sub->residual; - n = frame->blocksize; - - /* rice-encoded block */ - put_bits(&ctx->pb, 2, 0); - - /* partition order */ - porder = sub->rc.porder; - psize = n >> porder; - parts = (1 << porder); - put_bits(&ctx->pb, 4, porder); - res_cnt = psize - sub->order; - - /* residual */ - j = sub->order; - for(p=0; p<parts; p++) { - k = sub->rc.params[p]; - put_bits(&ctx->pb, 4, k); - if(p == 1) res_cnt = psize; - for(i=0; i<res_cnt && j<n; i++, j++) { - set_sr_golomb_flac(&ctx->pb, res[j], k, INT32_MAX, 0); - } - } -} - -static void output_subframe_fixed(FlacEncodeContext *ctx, int ch) -{ - int i; - FlacFrame *frame; - FlacSubframe *sub; - - frame = &ctx->frame; - sub = &frame->subframes[ch]; - - /* warm-up samples */ - for(i=0; i<sub->order; i++) { - put_sbits(&ctx->pb, sub->obits, sub->residual[i]); - } - - /* residual */ - output_residual(ctx, ch); -} - -static void output_subframe_lpc(FlacEncodeContext *ctx, int ch) -{ - int i, cbits; - FlacFrame *frame; - FlacSubframe *sub; - - frame = &ctx->frame; - sub = &frame->subframes[ch]; - - /* warm-up samples */ - for(i=0; i<sub->order; i++) { - put_sbits(&ctx->pb, sub->obits, sub->residual[i]); - } - - /* LPC coefficients */ - cbits = ctx->options.lpc_coeff_precision; - put_bits(&ctx->pb, 4, cbits-1); - put_sbits(&ctx->pb, 5, sub->shift); - for(i=0; i<sub->order; i++) { - put_sbits(&ctx->pb, cbits, sub->coefs[i]); - } - - /* residual */ - output_residual(ctx, ch); -} - -static void output_subframes(FlacEncodeContext *s) -{ - FlacFrame *frame; - FlacSubframe *sub; - int ch; - - frame = &s->frame; - - for(ch=0; ch<s->channels; ch++) { - sub = &frame->subframes[ch]; - - /* subframe header */ - put_bits(&s->pb, 1, 0); - put_bits(&s->pb, 6, sub->type_code); - put_bits(&s->pb, 1, 0); /* no wasted bits */ - - /* subframe */ - if(sub->type == FLAC_SUBFRAME_CONSTANT) { - output_subframe_constant(s, ch); - } else if(sub->type == FLAC_SUBFRAME_VERBATIM) { - output_subframe_verbatim(s, ch); - } else if(sub->type == FLAC_SUBFRAME_FIXED) { - output_subframe_fixed(s, ch); - } else if(sub->type == FLAC_SUBFRAME_LPC) { - output_subframe_lpc(s, ch); - } - } -} - -static void output_frame_footer(FlacEncodeContext *s) -{ - int crc; - flush_put_bits(&s->pb); - crc = bswap_16(av_crc(av_crc8005, 0, s->pb.buf, put_bits_count(&s->pb)>>3)); - put_bits(&s->pb, 16, crc); - flush_put_bits(&s->pb); -} - -static int flac_encode_frame(AVCodecContext *avctx, uint8_t *frame, - int buf_size, void *data) -{ - int ch; - FlacEncodeContext *s; - int16_t *samples = data; - int out_bytes; - - s = avctx->priv_data; - - s->blocksize = avctx->frame_size; - init_frame(s); - - copy_samples(s, samples); - - channel_decorrelation(s); - - for(ch=0; ch<s->channels; ch++) { - encode_residual(s, ch); - } - init_put_bits(&s->pb, frame, buf_size); - output_frame_header(s); - output_subframes(s); - output_frame_footer(s); - out_bytes = put_bits_count(&s->pb) >> 3; - - if(out_bytes > s->max_framesize || out_bytes >= buf_size) { - /* frame too large. use verbatim mode */ - for(ch=0; ch<s->channels; ch++) { - encode_residual_v(s, ch); - } - init_put_bits(&s->pb, frame, buf_size); - output_frame_header(s); - output_subframes(s); - output_frame_footer(s); - out_bytes = put_bits_count(&s->pb) >> 3; - - if(out_bytes > s->max_framesize || out_bytes >= buf_size) { - /* still too large. must be an error. */ - av_log(avctx, AV_LOG_ERROR, "error encoding frame\n"); - return -1; - } - } - - s->frame_count++; - return out_bytes; -} - -static int flac_encode_close(AVCodecContext *avctx) -{ - av_freep(&avctx->extradata); - avctx->extradata_size = 0; - av_freep(&avctx->coded_frame); - return 0; -} - -AVCodec flac_encoder = { - "flac", - CODEC_TYPE_AUDIO, - CODEC_ID_FLAC, - sizeof(FlacEncodeContext), - flac_encode_init, - flac_encode_frame, - flac_encode_close, - NULL, - .capabilities = CODEC_CAP_SMALL_LAST_FRAME, -}; |