X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fg726.c;h=c509292b6acbed6aeb5c96abc889862839ed0ee0;hb=849f10351d673ced1db6f13e399876f22121f60c;hp=a630c2a3eb1f718af6f74bd1009f05adf02767f9;hpb=eb5b0422b595d488f5c2f2a37a62cd46dfbb6aa7;p=ffmpeg diff --git a/libavcodec/g726.c b/libavcodec/g726.c index a630c2a3eb1..c509292b6ac 100644 --- a/libavcodec/g726.c +++ b/libavcodec/g726.c @@ -1,191 +1,194 @@ /* - * G.726 ADPCM audio codec + * G.726 ADPCM audio codec * Copyright (c) 2004 Roman Shaposhnik. * * This is a very straightforward rendition of the G.726 - * Section 4 "Computational Details". + * Section 4 "Computational Details". * - * This library is free software; you can redistribute it and/or + * 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 of the License, or (at your option) any later version. + * version 2.1 of the License, or (at your option) any later version. * - * This library is distributed in the hope that it will be useful, + * 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 this library; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include #include "avcodec.h" #include "common.h" +#include "bitstream.h" -/* - * G.726 Standard uses rather odd 11bit floating point arithmentic for +/** + * G.726 11bit float. + * G.726 Standard uses rather odd 11bit floating point arithmentic for * numerous occasions. It's a mistery to me why they did it this way * instead of simply using 32bit integer arithmetic. */ typedef struct Float11 { - int sign; /* 1bit sign */ - int exp; /* 4bit exponent */ - int mant; /* 6bit mantissa */ + int sign; /**< 1bit sign */ + int exp; /**< 4bit exponent */ + int mant; /**< 6bit mantissa */ } Float11; static inline Float11* i2f(int16_t i, Float11* f) { - f->sign = (i < 0); - if (f->sign) - i = -i; - f->exp = av_log2_16bit(i) + !!i; - f->mant = i? (i<<6) >> f->exp : - 1<<5; - return f; + f->sign = (i < 0); + if (f->sign) + i = -i; + f->exp = av_log2_16bit(i) + !!i; + f->mant = i? (i<<6) >> f->exp : 1<<5; + return f; } static inline int16_t mult(Float11* f1, Float11* f2) { - int res, exp; + int res, exp; - exp = f1->exp + f2->exp; - res = (((f1->mant * f2->mant) + 0x30) >> 4) << 7; - res = exp > 26 ? res << (exp - 26) : res >> (26 - exp); - return (f1->sign ^ f2->sign) ? -res : res; + exp = f1->exp + f2->exp; + res = (((f1->mant * f2->mant) + 0x30) >> 4) << 7; + res = exp > 26 ? res << (exp - 26) : res >> (26 - exp); + return (f1->sign ^ f2->sign) ? -res : res; } static inline int sgn(int value) { - return (value < 0) ? -1 : 1; + return (value < 0) ? -1 : 1; } typedef struct G726Tables { - int bits; /* bits per sample */ - int* quant; /* quantization table */ - int* iquant; /* inverse quantization table */ - int* W; /* special table #1 ;-) */ - int* F; /* special table #2 */ + int bits; /**< bits per sample */ + int* quant; /**< quantization table */ + int* iquant; /**< inverse quantization table */ + int* W; /**< special table #1 ;-) */ + int* F; /**< special table #2 */ } G726Tables; typedef struct G726Context { - G726Tables* tbls; /* static tables needed for computation */ - - Float11 sr[2]; /* prev. reconstructed samples */ - Float11 dq[6]; /* prev. difference */ - int a[2]; /* second order predictor coeffs */ - int b[6]; /* sixth order predictor coeffs */ - int pk[2]; /* signs of prev. 2 sez + dq */ - - int ap; /* scale factor control */ - int yu; /* fast scale factor */ - int yl; /* slow scale factor */ - int dms; /* short average magnitude of F[i] */ - int dml; /* long average magnitude of F[i] */ - int td; /* tone detect */ - - int se; /* estimated signal for the next iteration */ - int sez; /* estimated second order prediction */ - int y; /* quantizer scaling factor for the next iteration */ + G726Tables* tbls; /**< static tables needed for computation */ + + Float11 sr[2]; /**< prev. reconstructed samples */ + Float11 dq[6]; /**< prev. difference */ + int a[2]; /**< second order predictor coeffs */ + int b[6]; /**< sixth order predictor coeffs */ + int pk[2]; /**< signs of prev. 2 sez + dq */ + + int ap; /**< scale factor control */ + int yu; /**< fast scale factor */ + int yl; /**< slow scale factor */ + int dms; /**< short average magnitude of F[i] */ + int dml; /**< long average magnitude of F[i] */ + int td; /**< tone detect */ + + int se; /**< estimated signal for the next iteration */ + int sez; /**< estimated second order prediction */ + int y; /**< quantizer scaling factor for the next iteration */ } G726Context; -static int quant_tbl16[] = /* 16kbit/s 2bits per sample */ - { 260, INT_MAX }; +static int quant_tbl16[] = /**< 16kbit/s 2bits per sample */ + { 260, INT_MAX }; static int iquant_tbl16[] = { 116, 365, 365, 116 }; -static int W_tbl16[] = +static int W_tbl16[] = { -22, 439, 439, -22 }; static int F_tbl16[] = { 0, 7, 7, 0 }; - -static int quant_tbl24[] = /* 24kbit/s 3bits per sample */ + +static int quant_tbl24[] = /**< 24kbit/s 3bits per sample */ { 7, 217, 330, INT_MAX }; static int iquant_tbl24[] = { INT_MIN, 135, 273, 373, 373, 273, 135, INT_MIN }; -static int W_tbl24[] = - { -4, 30, 137, 582, 582, 137, 30, -4 }; +static int W_tbl24[] = + { -4, 30, 137, 582, 582, 137, 30, -4 }; static int F_tbl24[] = { 0, 1, 2, 7, 7, 2, 1, 0 }; - -static int quant_tbl32[] = /* 32kbit/s 4bits per sample */ + +static int quant_tbl32[] = /**< 32kbit/s 4bits per sample */ { -125, 79, 177, 245, 299, 348, 399, INT_MAX }; static int iquant_tbl32[] = - { INT_MIN, 4, 135, 213, 273, 323, 373, 425, - 425, 373, 323, 273, 213, 135, 4, INT_MIN }; -static int W_tbl32[] = + { INT_MIN, 4, 135, 213, 273, 323, 373, 425, + 425, 373, 323, 273, 213, 135, 4, INT_MIN }; +static int W_tbl32[] = { -12, 18, 41, 64, 112, 198, 355, 1122, - 1122, 355, 198, 112, 64, 41, 18, -12}; -static int F_tbl32[] = + 1122, 355, 198, 112, 64, 41, 18, -12}; +static int F_tbl32[] = { 0, 0, 0, 1, 1, 1, 3, 7, 7, 3, 1, 1, 1, 0, 0, 0 }; - -static int quant_tbl40[] = /* 40kbit/s 5bits per sample */ + +static int quant_tbl40[] = /**< 40kbit/s 5bits per sample */ { -122, -16, 67, 138, 197, 249, 297, 338, - 377, 412, 444, 474, 501, 527, 552, INT_MAX }; + 377, 412, 444, 474, 501, 527, 552, INT_MAX }; static int iquant_tbl40[] = - { INT_MIN, -66, 28, 104, 169, 224, 274, 318, - 358, 395, 429, 459, 488, 514, 539, 566, - 566, 539, 514, 488, 459, 429, 395, 358, - 318, 274, 224, 169, 104, 28, -66, INT_MIN }; -static int W_tbl40[] = + { INT_MIN, -66, 28, 104, 169, 224, 274, 318, + 358, 395, 429, 459, 488, 514, 539, 566, + 566, 539, 514, 488, 459, 429, 395, 358, + 318, 274, 224, 169, 104, 28, -66, INT_MIN }; +static int W_tbl40[] = { 14, 14, 24, 39, 40, 41, 58, 100, - 141, 179, 219, 280, 358, 440, 529, 696, - 696, 529, 440, 358, 280, 219, 179, 141, - 100, 58, 41, 40, 39, 24, 14, 14 }; -static int F_tbl40[] = + 141, 179, 219, 280, 358, 440, 529, 696, + 696, 529, 440, 358, 280, 219, 179, 141, + 100, 58, 41, 40, 39, 24, 14, 14 }; +static int F_tbl40[] = { 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 6, - 6, 6, 5, 4, 3, 2, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0 }; + 6, 6, 5, 4, 3, 2, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0 }; -static G726Tables G726Tables_pool[] = +static G726Tables G726Tables_pool[] = {{ 2, quant_tbl16, iquant_tbl16, W_tbl16, F_tbl16 }, - { 3, quant_tbl24, iquant_tbl24, W_tbl24, F_tbl24 }, - { 4, quant_tbl32, iquant_tbl32, W_tbl32, F_tbl32 }, + { 3, quant_tbl24, iquant_tbl24, W_tbl24, F_tbl24 }, + { 4, quant_tbl32, iquant_tbl32, W_tbl32, F_tbl32 }, { 5, quant_tbl40, iquant_tbl40, W_tbl40, F_tbl40 }}; - -/* - * Para 4.2.2 page 18: Adaptive quantizer. + +/** + * Para 4.2.2 page 18: Adaptive quantizer. */ static inline uint8_t quant(G726Context* c, int d) { - int sign, exp, i, dln; - - sign = i = 0; - if (d < 0) { - sign = 1; - d = -d; - } - exp = av_log2_16bit(d); - dln = ((exp<<7) + (((d<<7)>>exp)&0x7f)) - (c->y>>2); - - while (c->tbls->quant[i] < INT_MAX && c->tbls->quant[i] < dln) + int sign, exp, i, dln; + + sign = i = 0; + if (d < 0) { + sign = 1; + d = -d; + } + exp = av_log2_16bit(d); + dln = ((exp<<7) + (((d<<7)>>exp)&0x7f)) - (c->y>>2); + + while (c->tbls->quant[i] < INT_MAX && c->tbls->quant[i] < dln) ++i; - - if (sign) - i = ~i; - if (c->tbls->bits != 2 && i == 0) /* I'm not sure this is a good idea */ - i = 0xff; - return i; + if (sign) + i = ~i; + if (c->tbls->bits != 2 && i == 0) /* I'm not sure this is a good idea */ + i = 0xff; + + return i; } -/* +/** * Para 4.2.3 page 22: Inverse adaptive quantizer. */ static inline int16_t inverse_quant(G726Context* c, int i) { int dql, dex, dqt; - + dql = c->tbls->iquant[i] + (c->y >> 2); dex = (dql>>7) & 0xf; /* 4bit exponent */ dqt = (1<<7) + (dql & 0x7f); /* log2 -> linear */ - return (dql < 0) ? 0 : ((dqt<<7) >> (14-dex)); + return (dql < 0) ? 0 : ((dqt<<7) >> (14-dex)); } static inline int16_t g726_iterate(G726Context* c, int16_t I) { int dq, re_signal, pk0, fa1, i, tr, ylint, ylfrac, thr2, al, dq0; Float11 f; - + dq = inverse_quant(c, I); if (I >> (c->tbls->bits - 1)) /* get the sign */ dq = -dq; @@ -199,26 +202,26 @@ static inline int16_t g726_iterate(G726Context* c, int16_t I) tr = 1; else tr = 0; - + /* Update second order predictor coefficient A2 and A1 */ pk0 = (c->sez + dq) ? sgn(c->sez + dq) : 0; dq0 = dq ? sgn(dq) : 0; if (tr) { c->a[0] = 0; - c->a[1] = 0; + c->a[1] = 0; for (i=0; i<6; i++) - c->b[i] = 0; + c->b[i] = 0; } else { - /* This is a bit crazy, but it really is +255 not +256 */ - fa1 = clip((-c->a[0]*c->pk[0]*pk0)>>5, -256, 255); - - c->a[1] += 128*pk0*c->pk[1] + fa1 - (c->a[1]>>7); - c->a[1] = clip(c->a[1], -12288, 12288); + /* This is a bit crazy, but it really is +255 not +256 */ + fa1 = clip((-c->a[0]*c->pk[0]*pk0)>>5, -256, 255); + + c->a[1] += 128*pk0*c->pk[1] + fa1 - (c->a[1]>>7); + c->a[1] = clip(c->a[1], -12288, 12288); c->a[0] += 64*3*pk0*c->pk[0] - (c->a[0] >> 8); - c->a[0] = clip(c->a[0], -(15360 - c->a[1]), 15360 - c->a[1]); + c->a[0] = clip(c->a[0], -(15360 - c->a[1]), 15360 - c->a[1]); for (i=0; i<6; i++) - c->b[i] += 128*dq0*sgn(-c->dq[i].sign) - (c->b[i]>>8); + c->b[i] += 128*dq0*sgn(-c->dq[i].sign) - (c->b[i]>>8); } /* Update Dq and Sr and Pk */ @@ -227,38 +230,38 @@ static inline int16_t g726_iterate(G726Context* c, int16_t I) c->sr[1] = c->sr[0]; i2f(re_signal, &c->sr[0]); for (i=5; i>0; i--) - c->dq[i] = c->dq[i-1]; + c->dq[i] = c->dq[i-1]; i2f(dq, &c->dq[0]); c->dq[0].sign = I >> (c->tbls->bits - 1); /* Isn't it crazy ?!?! */ - + /* Update tone detect [I'm not sure 'tr == 0' is really needed] */ - c->td = (tr == 0 && c->a[1] < -11776); - + c->td = (tr == 0 && c->a[1] < -11776); + /* Update Ap */ c->dms += ((c->tbls->F[I]<<9) - c->dms) >> 5; c->dml += ((c->tbls->F[I]<<11) - c->dml) >> 7; - if (tr) - c->ap = 256; + if (tr) + c->ap = 256; else if (c->y > 1535 && !c->td && (abs((c->dms << 2) - c->dml) < (c->dml >> 3))) - c->ap += (-c->ap) >> 4; + c->ap += (-c->ap) >> 4; else - c->ap += (0x200 - c->ap) >> 4; + c->ap += (0x200 - c->ap) >> 4; /* Update Yu and Yl */ c->yu = clip(c->y + (((c->tbls->W[I] << 5) - c->y) >> 5), 544, 5120); c->yl += c->yu + ((-c->yl)>>6); - + /* Next iteration for Y */ al = (c->ap >= 256) ? 1<<6 : c->ap >> 2; c->y = (c->yl + (c->yu - (c->yl>>6))*al) >> 6; - + /* Next iteration for SE and SEZ */ c->se = 0; for (i=0; i<6; i++) - c->se += mult(i2f(c->b[i] >> 2, &f), &c->dq[i]); + c->se += mult(i2f(c->b[i] >> 2, &f), &c->dq[i]); c->sez = c->se >> 1; for (i=0; i<2; i++) - c->se += mult(i2f(c->a[i] >> 2, &f), &c->sr[i]); + c->se += mult(i2f(c->a[i] >> 2, &f), &c->sr[i]); c->se >>= 1; return clip(re_signal << 2, -0xffff, 0xffff); @@ -270,13 +273,13 @@ static int g726_reset(G726Context* c, int bit_rate) c->tbls = &G726Tables_pool[bit_rate/8000 - 2]; for (i=0; i<2; i++) { - i2f(0, &c->sr[i]); - c->a[i] = 0; - c->pk[i] = 1; + i2f(0, &c->sr[i]); + c->a[i] = 0; + c->pk[i] = 1; } for (i=0; i<6; i++) { - i2f(0, &c->dq[i]); - c->b[i] = 0; + i2f(0, &c->dq[i]); + c->b[i] = 0; } c->ap = 0; c->dms = 0; @@ -297,46 +300,60 @@ static int16_t g726_decode(G726Context* c, int16_t i) return g726_iterate(c, i); } +#ifdef CONFIG_ENCODERS static int16_t g726_encode(G726Context* c, int16_t sig) { - uint8_t i; - - i = quant(c, sig/4 - c->se) & ((1<tbls->bits) - 1); - g726_iterate(c, i); - return i; + uint8_t i; + + i = quant(c, sig/4 - c->se) & ((1<tbls->bits) - 1); + g726_iterate(c, i); + return i; } +#endif /* Interfacing to the libavcodec */ typedef struct AVG726Context { - G726Context c; - int bits_left; - int bit_buffer; - int code_size; + G726Context c; + int bits_left; + int bit_buffer; + int code_size; } AVG726Context; static int g726_init(AVCodecContext * avctx) { AVG726Context* c = (AVG726Context*)avctx->priv_data; - + if (avctx->channels != 1 || (avctx->bit_rate != 16000 && avctx->bit_rate != 24000 && - avctx->bit_rate != 32000 && avctx->bit_rate != 40000)) { + avctx->bit_rate != 32000 && avctx->bit_rate != 40000)) { av_log(avctx, AV_LOG_ERROR, "G726: unsupported audio format\n"); - return -1; + return -1; } - if (avctx->sample_rate != 8000 && avctx->strict_std_compliance>=0) { + if (avctx->sample_rate != 8000 && avctx->strict_std_compliance>FF_COMPLIANCE_INOFFICIAL) { av_log(avctx, AV_LOG_ERROR, "G726: unsupported audio format\n"); - return -1; + return -1; } g726_reset(&c->c, avctx->bit_rate); c->code_size = c->c.tbls->bits; c->bit_buffer = 0; c->bits_left = 0; + avctx->coded_frame = avcodec_alloc_frame(); + if (!avctx->coded_frame) + return -ENOMEM; + avctx->coded_frame->key_frame = 1; + + return 0; +} + +static int g726_close(AVCodecContext *avctx) +{ + av_freep(&avctx->coded_frame); return 0; } +#ifdef CONFIG_ENCODERS static int g726_encode_frame(AVCodecContext *avctx, uint8_t *dst, int buf_size, void *data) { @@ -347,12 +364,13 @@ static int g726_encode_frame(AVCodecContext *avctx, init_put_bits(&pb, dst, 1024*1024); for (; buf_size; buf_size--) - put_bits(&pb, c->code_size, g726_encode(&c->c, *samples++)); + put_bits(&pb, c->code_size, g726_encode(&c->c, *samples++)); flush_put_bits(&pb); - return put_bits_count(&pb)>>3; -} + return put_bits_count(&pb)>>3; +} +#endif static int g726_decode_frame(AVCodecContext *avctx, void *data, int *data_size, @@ -362,25 +380,25 @@ static int g726_decode_frame(AVCodecContext *avctx, short *samples = data; uint8_t code; uint8_t mask; - GetBitContext gb; - + GetBitContext gb; + if (!buf_size) goto out; - + mask = (1<code_size) - 1; init_get_bits(&gb, buf, buf_size * 8); if (c->bits_left) { int s = c->code_size - c->bits_left;; - code = (c->bit_buffer << s) | get_bits(&gb, s); - *samples++ = g726_decode(&c->c, code & mask); + code = (c->bit_buffer << s) | get_bits(&gb, s); + *samples++ = g726_decode(&c->c, code & mask); } - + while (get_bits_count(&gb) + c->code_size <= buf_size*8) - *samples++ = g726_decode(&c->c, get_bits(&gb, c->code_size) & mask); - + *samples++ = g726_decode(&c->c, get_bits(&gb, c->code_size) & mask); + c->bits_left = buf_size*8 - get_bits_count(&gb); c->bit_buffer = get_bits(&gb, c->bits_left); - + out: *data_size = (uint8_t*)samples - (uint8_t*)data; return buf_size; @@ -394,7 +412,7 @@ AVCodec adpcm_g726_encoder = { sizeof(AVG726Context), g726_init, g726_encode_frame, - NULL, + g726_close, NULL, }; #endif //CONFIG_ENCODERS @@ -406,6 +424,6 @@ AVCodec adpcm_g726_decoder = { sizeof(AVG726Context), g726_init, NULL, - NULL, + g726_close, g726_decode_frame, };