History

Add G.722 ADPCM audio decoder

Originally committed as revision 25086 to svn://svn.ffmpeg.org/ffmpeg/trunk

Martin Storsjö committed 16 years ago

Commit 58e37ea1 parent a3f0d2b6 files · +311 −2Browse files

Unified · Split

6 files
  1. Changelog +1 −0
  2. doc/general.texi +1 −0
  3. libavcodec/Makefile +1 −0
  4. libavcodec/allcodecs.c +1 −0
  5. libavcodec/avcodec.h +3 −2
  6. libavcodec/g722.c +304 −0
Changelog+1−0
@@ -33,6 +33,7 @@ version <next>: · 32 unmodified lines
3333 - Apple HTTP Live Streaming demuxer
3434 - a64 codec
3535 - MMS-HTTP support
36+- G.722 ADPCM audio decoder
3637
3738
3839 version 0.6:
doc/general.texi+1−0
@@ -535,6 +535,7 @@ following image formats are supported: · 534 unmodified lines
535535 @item ADPCM Electronic Arts R2 @tab @tab X
536536 @item ADPCM Electronic Arts R3 @tab @tab X
537537 @item ADPCM Electronic Arts XAS @tab @tab X
538+@item ADPCM G.722 @tab @tab X
538539 @item ADPCM G.726 @tab X @tab X
539540 @item ADPCM IMA AMV @tab @tab X
540541 @tab Used in AMV files
libavcodec/Makefile+1−0
@@ -475,6 +475,7 @@ OBJS-$(CONFIG_ADPCM_EA_R1_DECODER) += adpcm.o · 474 unmodified lines
475475 OBJS-$(CONFIG_ADPCM_EA_R2_DECODER) += adpcm.o
476476 OBJS-$(CONFIG_ADPCM_EA_R3_DECODER) += adpcm.o
477477 OBJS-$(CONFIG_ADPCM_EA_XAS_DECODER) += adpcm.o
478+OBJS-$(CONFIG_ADPCM_G722_DECODER) += g722.o
478479 OBJS-$(CONFIG_ADPCM_G726_DECODER) += g726.o
479480 OBJS-$(CONFIG_ADPCM_G726_ENCODER) += g726.o
480481 OBJS-$(CONFIG_ADPCM_IMA_AMV_DECODER) += adpcm.o
libavcodec/allcodecs.c+1−0
@@ -317,6 +317,7 @@ void avcodec_register_all(void) · 316 unmodified lines
317317 REGISTER_DECODER (ADPCM_EA_R2, adpcm_ea_r2);
318318 REGISTER_DECODER (ADPCM_EA_R3, adpcm_ea_r3);
319319 REGISTER_DECODER (ADPCM_EA_XAS, adpcm_ea_xas);
320+ REGISTER_DECODER (ADPCM_G722, adpcm_g722);
320321 REGISTER_ENCDEC (ADPCM_G726, adpcm_g726);
321322 REGISTER_DECODER (ADPCM_IMA_AMV, adpcm_ima_amv);
322323 REGISTER_DECODER (ADPCM_IMA_DK3, adpcm_ima_dk3);
libavcodec/avcodec.h+3−2
@@ -31,8 +31,8 @@ · 30 unmodified lines
3131 #include "libavutil/cpu.h"
3232
3333 #define LIBAVCODEC_VERSION_MAJOR 52
34−#define LIBAVCODEC_VERSION_MINOR 87
35−#define LIBAVCODEC_VERSION_MICRO 5
34+#define LIBAVCODEC_VERSION_MINOR 88
35+#define LIBAVCODEC_VERSION_MICRO 0
3636
3737 #define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
3838 LIBAVCODEC_VERSION_MINOR, \
@@ -284,6 +284,7 @@ enum CodecID { · 245 unmodified lines
284284 CODEC_ID_ADPCM_EA_XAS,
285285 CODEC_ID_ADPCM_EA_MAXIS_XA,
286286 CODEC_ID_ADPCM_IMA_ISS,
287+ CODEC_ID_ADPCM_G722,
287288
288289 /* AMR */
289290 CODEC_ID_AMR_NB= 0x12000,
libavcodec/g722.c+304−0
@@ -0,0 +1,304 @@
1+/*
2+ * G.722 ADPCM audio decoder
3+ *
4+ * Copyright (c) CMU 1993 Computer Science, Speech Group
5+ * Chengxiang Lu and Alex Hauptmann
6+ * Copyright (c) 2005 Steve Underwood <steveu at coppice.org>
7+ * Copyright (c) 2009 Kenan Gillet
8+ * Copyright (c) 2010 Martin Storsjo
9+ *
10+ * This file is part of FFmpeg.
11+ *
12+ * FFmpeg is free software; you can redistribute it and/or
13+ * modify it under the terms of the GNU Lesser General Public
14+ * License as published by the Free Software Foundation; either
15+ * version 2.1 of the License, or (at your option) any later version.
16+ *
17+ * FFmpeg is distributed in the hope that it will be useful,
18+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
19+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20+ * Lesser General Public License for more details.
21+ *
22+ * You should have received a copy of the GNU Lesser General Public
23+ * License along with FFmpeg; if not, write to the Free Software
24+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25+ */
26+
27+/**
28+ * @file
29+ *
30+ * G.722 ADPCM audio codec
31+ *
32+ * This G.722 decoder is a bit-exact implementation of the ITU G.722
33+ * specification for all three specified bitrates - 64000bps, 56000bps
34+ * and 48000bps. It passes the ITU tests.
35+ *
36+ * @note For the 56000bps and 48000bps bitrates, the lowest 1 or 2 bits
37+ * respectively of each byte are ignored.
38+ */
39+
40+#include "avcodec.h"
41+#include "mathops.h"
42+#include "get_bits.h"
43+
44+#define PREV_SAMPLES_BUF_SIZE 1024
45+
46+typedef struct {
47+ int16_t prev_samples[PREV_SAMPLES_BUF_SIZE]; ///< memory of past decoded samples
48+ int prev_samples_pos; ///< the number of values in prev_samples
49+
50+ /**
51+ * The band[0] and band[1] correspond respectively to the lower band and higher band.
52+ */
53+ struct G722Band {
54+ int16_t s_predictor; ///< predictor output value
55+ int32_t s_zero; ///< previous output signal from zero predictor
56+ int8_t part_reconst_mem[2]; ///< signs of previous partially reconstructed signals
57+ int16_t prev_qtzd_reconst; ///< previous quantized reconstructed signal (internal value, using low_inv_quant4)
58+ int16_t pole_mem[2]; ///< second-order pole section coefficient buffer
59+ int32_t diff_mem[6]; ///< quantizer difference signal memory
60+ int16_t zero_mem[6]; ///< Seventh-order zero section coefficient buffer
61+ int16_t log_factor; ///< delayed 2-logarithmic quantizer factor
62+ int16_t scale_factor; ///< delayed quantizer scale factor
63+ } band[2];
64+} G722Context;
65+
66+
67+static const int8_t sign_lookup[2] = { -1, 1 };
68+
69+static const int16_t inv_log2_table[32] = {
70+ 2048, 2093, 2139, 2186, 2233, 2282, 2332, 2383,
71+ 2435, 2489, 2543, 2599, 2656, 2714, 2774, 2834,
72+ 2896, 2960, 3025, 3091, 3158, 3228, 3298, 3371,
73+ 3444, 3520, 3597, 3676, 3756, 3838, 3922, 4008
74+};
75+static const int16_t high_log_factor_step[2] = { 798, -214 };
76+static const int16_t high_inv_quant[4] = { -926, -202, 926, 202 };
77+/**
78+ * low_log_factor_step[index] == wl[rl42[index]]
79+ */
80+static const int16_t low_log_factor_step[16] = {
81+ -60, 3042, 1198, 538, 334, 172, 58, -30,
82+ 3042, 1198, 538, 334, 172, 58, -30, -60
83+};
84+static const int16_t low_inv_quant4[16] = {
85+ 0, -2557, -1612, -1121, -786, -530, -323, -150,
86+ 2557, 1612, 1121, 786, 530, 323, 150, 0
87+};
88+
89+/**
90+ * quadrature mirror filter (QMF) coefficients
91+ *
92+ * ITU-T G.722 Table 11
93+ */
94+static const int16_t qmf_coeffs[12] = {
95+ 3, -11, 12, 32, -210, 951, 3876, -805, 362, -156, 53, -11,
96+};
97+
98+
99+/**
100+ * adaptive predictor
101+ *
102+ * @param cur_diff the dequantized and scaled delta calculated from the
103+ * current codeword
104+ */
105+static void do_adaptive_prediction(struct G722Band *band, const int cur_diff)
106+{
107+ int sg[2], limit, i, cur_qtzd_reconst;
108+
109+ const int cur_part_reconst = band->s_zero + cur_diff < 0;
110+
111+ sg[0] = sign_lookup[cur_part_reconst != band->part_reconst_mem[0]];
112+ sg[1] = sign_lookup[cur_part_reconst == band->part_reconst_mem[1]];
113+ band->part_reconst_mem[1] = band->part_reconst_mem[0];
114+ band->part_reconst_mem[0] = cur_part_reconst;
115+
116+ band->pole_mem[1] = av_clip((sg[0] * av_clip(band->pole_mem[0], -8191, 8191) >> 5) +
117+ (sg[1] << 7) + (band->pole_mem[1] * 127 >> 7), -12288, 12288);
118+
119+ limit = 15360 - band->pole_mem[1];
120+ band->pole_mem[0] = av_clip(-192 * sg[0] + (band->pole_mem[0] * 255 >> 8), -limit, limit);
121+
122+
123+ if (cur_diff) {
124+ for (i = 0; i < 6; i++)
125+ band->zero_mem[i] = ((band->zero_mem[i]*255) >> 8) +
126+ ((band->diff_mem[i]^cur_diff) < 0 ? -128 : 128);
127+ } else
128+ for (i = 0; i < 6; i++)
129+ band->zero_mem[i] = (band->zero_mem[i]*255) >> 8;
130+
131+ for (i = 5; i > 0; i--)
132+ band->diff_mem[i] = band->diff_mem[i-1];
133+ band->diff_mem[0] = av_clip_int16(cur_diff << 1);
134+
135+ band->s_zero = 0;
136+ for (i = 5; i >= 0; i--)
137+ band->s_zero += (band->zero_mem[i]*band->diff_mem[i]) >> 15;
138+
139+
140+ cur_qtzd_reconst = av_clip_int16((band->s_predictor + cur_diff) << 1);
141+ band->s_predictor = av_clip_int16(band->s_zero +
142+ (band->pole_mem[0] * cur_qtzd_reconst >> 15) +
143+ (band->pole_mem[1] * band->prev_qtzd_reconst >> 15));
144+ band->prev_qtzd_reconst = cur_qtzd_reconst;
145+}
146+
147+static int inline linear_scale_factor(const int log_factor)
148+{
149+ const int wd1 = inv_log2_table[(log_factor >> 6) & 31];
150+ const int shift = log_factor >> 11;
151+ return shift < 0 ? wd1 >> -shift : wd1 << shift;
152+}
153+
154+static void update_low_predictor(struct G722Band *band, const int ilow)
155+{
156+ do_adaptive_prediction(band,
157+ band->scale_factor * low_inv_quant4[ilow] >> 10);
158+
159+ // quantizer adaptation
160+ band->log_factor = av_clip((band->log_factor * 127 >> 7) +
161+ low_log_factor_step[ilow], 0, 18432);
162+ band->scale_factor = linear_scale_factor(band->log_factor - (8 << 11));
163+}
164+
165+static void update_high_predictor(struct G722Band *band, const int dhigh,
166+ const int ihigh)
167+{
168+ do_adaptive_prediction(band, dhigh);
169+
170+ // quantizer adaptation
171+ band->log_factor = av_clip((band->log_factor * 127 >> 7) +
172+ high_log_factor_step[ihigh&1], 0, 22528);
173+ band->scale_factor = linear_scale_factor(band->log_factor - (10 << 11));
174+}
175+
176+static void apply_qmf(const int16_t *prev_samples, int *xout1, int *xout2)
177+{
178+ int i;
179+
180+ *xout1 = 0;
181+ *xout2 = 0;
182+ for (i = 0; i < 12; i++) {
183+ MAC16(*xout2, prev_samples[2*i ], qmf_coeffs[i ]);
184+ MAC16(*xout1, prev_samples[2*i+1], qmf_coeffs[11-i]);
185+ }
186+}
187+
188+static av_cold int g722_init(AVCodecContext * avctx)
189+{
190+ G722Context *c = avctx->priv_data;
191+
192+ if (avctx->channels != 1) {
193+ av_log(avctx, AV_LOG_ERROR, "Only mono tracks are allowed.\n");
194+ return AVERROR_INVALIDDATA;
195+ }
196+ avctx->sample_fmt = SAMPLE_FMT_S16;
197+
198+ switch (avctx->bits_per_coded_sample) {
199+ case 8:
200+ case 7:
201+ case 6:
202+ break;
203+ default:
204+ av_log(avctx, AV_LOG_WARNING, "Unsupported bits_per_coded_sample [%d], "
205+ "assuming 8\n",
206+ avctx->bits_per_coded_sample);
207+ case 0:
208+ avctx->bits_per_coded_sample = 8;
209+ break;
210+ }
211+
212+ c->band[0].scale_factor = 8;
213+ c->band[1].scale_factor = 2;
214+ c->prev_samples_pos = 22;
215+
216+ if (avctx->lowres)
217+ avctx->sample_rate /= 2;
218+
219+ return 0;
220+}
221+
222+static const int16_t low_inv_quant5[32] = {
223+ -35, -35, -2919, -2195, -1765, -1458, -1219, -1023,
224+ -858, -714, -587, -473, -370, -276, -190, -110,
225+ 2919, 2195, 1765, 1458, 1219, 1023, 858, 714,
226+ 587, 473, 370, 276, 190, 110, 35, -35
227+};
228+static const int16_t low_inv_quant6[64] = {
229+ -17, -17, -17, -17, -3101, -2738, -2376, -2088,
230+ -1873, -1689, -1535, -1399, -1279, -1170, -1072, -982,
231+ -899, -822, -750, -682, -618, -558, -501, -447,
232+ -396, -347, -300, -254, -211, -170, -130, -91,
233+ 3101, 2738, 2376, 2088, 1873, 1689, 1535, 1399,
234+ 1279, 1170, 1072, 982, 899, 822, 750, 682,
235+ 618, 558, 501, 447, 396, 347, 300, 254,
236+ 211, 170, 130, 91, 54, 17, -54, -17
237+};
238+
239+static const int16_t *low_inv_quants[3] = { low_inv_quant6, low_inv_quant5,
240+ low_inv_quant4 };
241+
242+static int g722_decode_frame(AVCodecContext *avctx, void *data,
243+ int *data_size, AVPacket *avpkt)
244+{
245+ G722Context *c = avctx->priv_data;
246+ int16_t *out_buf = data;
247+ int j, out_len = 0;
248+ const int skip = 8 - avctx->bits_per_coded_sample;
249+ const int16_t *quantizer_table = low_inv_quants[skip];
250+ GetBitContext gb;
251+
252+ init_get_bits(&gb, avpkt->data, avpkt->size * 8);
253+
254+ for (j = 0; j < avpkt->size; j++) {
255+ int ilow, ihigh, rlow;
256+
257+ ihigh = get_bits(&gb, 2);
258+ ilow = get_bits(&gb, 6 - skip);
259+ skip_bits(&gb, skip);
260+
261+ rlow = av_clip((c->band[0].scale_factor * quantizer_table[ilow] >> 10)
262+ + c->band[0].s_predictor, -16384, 16383);
263+
264+ update_low_predictor(&c->band[0], ilow >> (2 - skip));
265+
266+ if (!avctx->lowres) {
267+ const int dhigh = c->band[1].scale_factor *
268+ high_inv_quant[ihigh] >> 10;
269+ const int rhigh = av_clip(dhigh + c->band[1].s_predictor,
270+ -16384, 16383);
271+ int xout1, xout2;
272+
273+ update_high_predictor(&c->band[1], dhigh, ihigh);
274+
275+ c->prev_samples[c->prev_samples_pos++] = rlow + rhigh;
276+ c->prev_samples[c->prev_samples_pos++] = rlow - rhigh;
277+ apply_qmf(c->prev_samples + c->prev_samples_pos - 24,
278+ &xout1, &xout2);
279+ out_buf[out_len++] = av_clip_int16(xout1 >> 12);
280+ out_buf[out_len++] = av_clip_int16(xout2 >> 12);
281+ if (c->prev_samples_pos >= PREV_SAMPLES_BUF_SIZE) {
282+ memmove(c->prev_samples,
283+ c->prev_samples + c->prev_samples_pos - 22,
284+ 22 * sizeof(c->prev_samples[0]));
285+ c->prev_samples_pos = 22;
286+ }
287+ } else
288+ out_buf[out_len++] = rlow;
289+ }
290+ *data_size = out_len << 1;
291+ return avpkt->size;
292+}
293+
294+AVCodec adpcm_g722_decoder = {
295+ .name = "g722",
296+ .type = AVMEDIA_TYPE_AUDIO,
297+ .id = CODEC_ID_ADPCM_G722,
298+ .priv_data_size = sizeof(G722Context),
299+ .init = g722_init,
300+ .decode = g722_decode_frame,
301+ .long_name = NULL_IF_CONFIG_SMALL("G.722 ADPCM"),
302+ .max_lowres = 1,
303+};
304+

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