History

Add native GSM 06.10 audio decoder.

Originally committed as revision 24158 to svn://svn.ffmpeg.org/ffmpeg/trunk

Reimar Döffinger committed 16 years ago

Commit b5769341 parent a6f8f116 files · +326 −5Browse files

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6 files
  1. Changelog +1 −0
  2. doc/general.texi +4 −4
  3. libavcodec/Makefile +2 −0
  4. libavcodec/allcodecs.c +2 −0
  5. libavcodec/avcodec.h +1 −1
  6. libavcodec/gsmdec.c +316 −0
Changelog+1−0
@@ -19,6 +19,7 @@ version <next>: · 18 unmodified lines
1919 - RTP depacketization of SVQ3
2020 - -strict inofficial replaced by -strict unofficial
2121 - ffplay -exitonkeydown and -exitonmousedown options added
22+- native GSM / GSM MS decoder
2223
2324
2425
doc/general.texi+4−4
@@ -589,10 +589,10 @@ following image formats are supported: · 588 unmodified lines
589589 @item Enhanced AC-3 @tab @tab X
590590 @item FLAC (Free Lossless Audio Codec) @tab X @tab IX
591591 @item G.729 @tab @tab X
592−@item GSM @tab E @tab E
593− @tab supported through external library libgsm
594−@item GSM Microsoft variant @tab E @tab E
595− @tab supported through external library libgsm
592+@item GSM @tab E @tab X
593+ @tab encoding supported through external library libgsm
594+@item GSM Microsoft variant @tab E @tab X
595+ @tab encoding supported through external library libgsm
596596 @item IMC (Intel Music Coder) @tab @tab X
597597 @item MACE (Macintosh Audio Compression/Expansion) 3:1 @tab @tab X
598598 @item MACE (Macintosh Audio Compression/Expansion) 6:1 @tab @tab X
libavcodec/Makefile+2−0
@@ -130,6 +130,8 @@ OBJS-$(CONFIG_FRAPS_DECODER) += fraps.o huffman.o · 129 unmodified lines
130130 OBJS-$(CONFIG_FRWU_DECODER) += frwu.o
131131 OBJS-$(CONFIG_GIF_DECODER) += gifdec.o lzw.o
132132 OBJS-$(CONFIG_GIF_ENCODER) += gif.o lzwenc.o
133+OBJS-$(CONFIG_GSM_DECODER) += gsmdec.o
134+OBJS-$(CONFIG_GSM_MS_DECODER) += gsmdec.o
133135 OBJS-$(CONFIG_H261_DECODER) += h261dec.o h261.o \
134136 mpegvideo.o error_resilience.o
135137 OBJS-$(CONFIG_H261_ENCODER) += h261enc.o h261.o \
libavcodec/allcodecs.c+2−0
@@ -230,6 +230,8 @@ void avcodec_register_all(void) · 229 unmodified lines
230230 REGISTER_DECODER (DSICINAUDIO, dsicinaudio);
231231 REGISTER_DECODER (EAC3, eac3);
232232 REGISTER_ENCDEC (FLAC, flac);
233+ REGISTER_DECODER (GSM, gsm);
234+ REGISTER_DECODER (GSM_MS, gsm_ms);
233235 REGISTER_DECODER (IMC, imc);
234236 REGISTER_DECODER (MACE3, mace3);
235237 REGISTER_DECODER (MACE6, mace6);
libavcodec/avcodec.h+1−1
@@ -30,7 +30,7 @@ · 29 unmodified lines
3030 #include "libavutil/avutil.h"
3131
3232 #define LIBAVCODEC_VERSION_MAJOR 52
33−#define LIBAVCODEC_VERSION_MINOR 80
33+#define LIBAVCODEC_VERSION_MINOR 81
3434 #define LIBAVCODEC_VERSION_MICRO 0
3535
3636 #define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
libavcodec/gsmdec.c+316−0
@@ -0,0 +1,316 @@
1+/*
2+ * gsm 06.10 decoder
3+ * Copyright (c) 2010 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
4+ *
5+ * This file is part of FFmpeg.
6+ *
7+ * FFmpeg is free software; you can redistribute it and/or
8+ * modify it under the terms of the GNU Lesser General Public
9+ * License as published by the Free Software Foundation; either
10+ * version 2.1 of the License, or (at your option) any later version.
11+ *
12+ * FFmpeg is distributed in the hope that it will be useful,
13+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
14+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15+ * Lesser General Public License for more details.
16+ *
17+ * You should have received a copy of the GNU Lesser General Public
18+ * License along with FFmpeg; if not, write to the Free Software
19+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20+ */
21+
22+/**
23+ * @file
24+ * GSM decoder
25+ */
26+
27+#define ALT_BITSTREAM_READER_LE
28+#include "avcodec.h"
29+#include "get_bits.h"
30+
31+// input and output sizes in byte
32+#define GSM_BLOCK_SIZE 33
33+#define GSM_MS_BLOCK_SIZE 65
34+#define GSM_FRAME_SIZE 160
35+
36+typedef struct {
37+ int16_t ref_buf[280];
38+ int v[9];
39+ int lar[2][8];
40+ int lar_idx;
41+ int msr;
42+} GSMContext;
43+
44+static av_cold int gsm_init(AVCodecContext *avctx)
45+{
46+ avctx->channels = 1;
47+ if (!avctx->sample_rate)
48+ avctx->sample_rate = 8000;
49+ avctx->sample_fmt = SAMPLE_FMT_S16;
50+
51+ switch (avctx->codec_id) {
52+ case CODEC_ID_GSM:
53+ avctx->frame_size = GSM_FRAME_SIZE;
54+ avctx->block_align = GSM_BLOCK_SIZE;
55+ break;
56+ case CODEC_ID_GSM_MS:
57+ avctx->frame_size = 2 * GSM_FRAME_SIZE;
58+ avctx->block_align = GSM_MS_BLOCK_SIZE;
59+ }
60+
61+ return 0;
62+}
63+
64+static const int16_t dequant_tab[64][8] = {
65+ { -28, -20, -12, -4, 4, 12, 20, 28},
66+ { -56, -40, -24, -8, 8, 24, 40, 56},
67+ { -84, -60, -36, -12, 12, 36, 60, 84},
68+ { -112, -80, -48, -16, 16, 48, 80, 112},
69+ { -140, -100, -60, -20, 20, 60, 100, 140},
70+ { -168, -120, -72, -24, 24, 72, 120, 168},
71+ { -196, -140, -84, -28, 28, 84, 140, 196},
72+ { -224, -160, -96, -32, 32, 96, 160, 224},
73+ { -252, -180, -108, -36, 36, 108, 180, 252},
74+ { -280, -200, -120, -40, 40, 120, 200, 280},
75+ { -308, -220, -132, -44, 44, 132, 220, 308},
76+ { -336, -240, -144, -48, 48, 144, 240, 336},
77+ { -364, -260, -156, -52, 52, 156, 260, 364},
78+ { -392, -280, -168, -56, 56, 168, 280, 392},
79+ { -420, -300, -180, -60, 60, 180, 300, 420},
80+ { -448, -320, -192, -64, 64, 192, 320, 448},
81+ { -504, -360, -216, -72, 72, 216, 360, 504},
82+ { -560, -400, -240, -80, 80, 240, 400, 560},
83+ { -616, -440, -264, -88, 88, 264, 440, 616},
84+ { -672, -480, -288, -96, 96, 288, 480, 672},
85+ { -728, -520, -312, -104, 104, 312, 520, 728},
86+ { -784, -560, -336, -112, 112, 336, 560, 784},
87+ { -840, -600, -360, -120, 120, 360, 600, 840},
88+ { -896, -640, -384, -128, 128, 384, 640, 896},
89+ { -1008, -720, -432, -144, 144, 432, 720, 1008},
90+ { -1120, -800, -480, -160, 160, 480, 800, 1120},
91+ { -1232, -880, -528, -176, 176, 528, 880, 1232},
92+ { -1344, -960, -576, -192, 192, 576, 960, 1344},
93+ { -1456, -1040, -624, -208, 208, 624, 1040, 1456},
94+ { -1568, -1120, -672, -224, 224, 672, 1120, 1568},
95+ { -1680, -1200, -720, -240, 240, 720, 1200, 1680},
96+ { -1792, -1280, -768, -256, 256, 768, 1280, 1792},
97+ { -2016, -1440, -864, -288, 288, 864, 1440, 2016},
98+ { -2240, -1600, -960, -320, 320, 960, 1600, 2240},
99+ { -2464, -1760, -1056, -352, 352, 1056, 1760, 2464},
100+ { -2688, -1920, -1152, -384, 384, 1152, 1920, 2688},
101+ { -2912, -2080, -1248, -416, 416, 1248, 2080, 2912},
102+ { -3136, -2240, -1344, -448, 448, 1344, 2240, 3136},
103+ { -3360, -2400, -1440, -480, 480, 1440, 2400, 3360},
104+ { -3584, -2560, -1536, -512, 512, 1536, 2560, 3584},
105+ { -4032, -2880, -1728, -576, 576, 1728, 2880, 4032},
106+ { -4480, -3200, -1920, -640, 640, 1920, 3200, 4480},
107+ { -4928, -3520, -2112, -704, 704, 2112, 3520, 4928},
108+ { -5376, -3840, -2304, -768, 768, 2304, 3840, 5376},
109+ { -5824, -4160, -2496, -832, 832, 2496, 4160, 5824},
110+ { -6272, -4480, -2688, -896, 896, 2688, 4480, 6272},
111+ { -6720, -4800, -2880, -960, 960, 2880, 4800, 6720},
112+ { -7168, -5120, -3072, -1024, 1024, 3072, 5120, 7168},
113+ { -8063, -5759, -3456, -1152, 1152, 3456, 5760, 8064},
114+ { -8959, -6399, -3840, -1280, 1280, 3840, 6400, 8960},
115+ { -9855, -7039, -4224, -1408, 1408, 4224, 7040, 9856},
116+ {-10751, -7679, -4608, -1536, 1536, 4608, 7680, 10752},
117+ {-11647, -8319, -4992, -1664, 1664, 4992, 8320, 11648},
118+ {-12543, -8959, -5376, -1792, 1792, 5376, 8960, 12544},
119+ {-13439, -9599, -5760, -1920, 1920, 5760, 9600, 13440},
120+ {-14335, -10239, -6144, -2048, 2048, 6144, 10240, 14336},
121+ {-16127, -11519, -6912, -2304, 2304, 6912, 11519, 16127},
122+ {-17919, -12799, -7680, -2560, 2560, 7680, 12799, 17919},
123+ {-19711, -14079, -8448, -2816, 2816, 8448, 14079, 19711},
124+ {-21503, -15359, -9216, -3072, 3072, 9216, 15359, 21503},
125+ {-23295, -16639, -9984, -3328, 3328, 9984, 16639, 23295},
126+ {-25087, -17919, -10752, -3584, 3584, 10752, 17919, 25087},
127+ {-26879, -19199, -11520, -3840, 3840, 11520, 19199, 26879},
128+ {-28671, -20479, -12288, -4096, 4096, 12288, 20479, 28671}
129+};
130+
131+static void apcm_dequant_add(GetBitContext *gb, int16_t *dst)
132+{
133+ int i;
134+ int maxidx = get_bits(gb, 6);
135+ const int16_t *tab = dequant_tab[maxidx];
136+ for (i = 0; i < 13; i++)
137+ dst[3*i] += tab[get_bits(gb, 3)];
138+}
139+
140+static inline int gsm_mult(int a, int b)
141+{
142+ return (a * b + (1 << 14)) >> 15;
143+}
144+
145+static const uint16_t long_term_gain_tab[4] = {
146+ 3277, 11469, 21299, 32767
147+};
148+
149+static void long_term_synth(int16_t *dst, int lag, int gain_idx)
150+{
151+ int i;
152+ const int16_t *src = dst - lag;
153+ uint16_t gain = long_term_gain_tab[gain_idx];
154+ for (i = 0; i < 40; i++)
155+ dst[i] = gsm_mult(gain, src[i]);
156+}
157+
158+static inline int decode_log_area(int coded, int factor, int offset)
159+{
160+ coded <<= 10;
161+ coded -= offset;
162+ return gsm_mult(coded, factor) << 1;
163+}
164+
165+static av_noinline int get_rrp(int filtered)
166+{
167+ int abs = FFABS(filtered);
168+ if (abs < 11059) abs <<= 1;
169+ else if (abs < 20070) abs += 11059;
170+ else abs = (abs >> 2) + 26112;
171+ return filtered < 0 ? -abs : abs;
172+}
173+
174+static int filter_value(int in, int rrp[8], int v[9])
175+{
176+ int i;
177+ for (i = 7; i >= 0; i--) {
178+ in -= gsm_mult(rrp[i], v[i]);
179+ v[i + 1] = v[i] + gsm_mult(rrp[i], in);
180+ }
181+ v[0] = in;
182+ return in;
183+}
184+
185+static void short_term_synth(GSMContext *ctx, int16_t *dst, const int16_t *src)
186+{
187+ int i;
188+ int rrp[8];
189+ int *lar = ctx->lar[ctx->lar_idx];
190+ int *lar_prev = ctx->lar[ctx->lar_idx ^ 1];
191+ for (i = 0; i < 8; i++)
192+ rrp[i] = get_rrp((lar_prev[i] >> 2) + (lar_prev[i] >> 1) + (lar[i] >> 2));
193+ for (i = 0; i < 13; i++)
194+ dst[i] = filter_value(src[i], rrp, ctx->v);
195+
196+ for (i = 0; i < 8; i++)
197+ rrp[i] = get_rrp((lar_prev[i] >> 1) + (lar [i] >> 1));
198+ for (i = 13; i < 27; i++)
199+ dst[i] = filter_value(src[i], rrp, ctx->v);
200+
201+ for (i = 0; i < 8; i++)
202+ rrp[i] = get_rrp((lar_prev[i] >> 2) + (lar [i] >> 1) + (lar[i] >> 2));
203+ for (i = 27; i < 40; i++)
204+ dst[i] = filter_value(src[i], rrp, ctx->v);
205+
206+ for (i = 0; i < 8; i++)
207+ rrp[i] = get_rrp(lar[i]);
208+ for (i = 40; i < 160; i++)
209+ dst[i] = filter_value(src[i], rrp, ctx->v);
210+
211+ ctx->lar_idx ^= 1;
212+}
213+
214+static int postprocess(int16_t *data, int msr)
215+{
216+ int i;
217+ for (i = 0; i < 160; i++) {
218+ msr = av_clip_int16(data[i] + gsm_mult(msr, 28180));
219+ data[i] = av_clip_int16(msr << 1) & ~7;
220+ }
221+ return msr;
222+}
223+
224+static int gsm_decode_block(AVCodecContext *avctx, int16_t *samples,
225+ GetBitContext *gb)
226+{
227+ GSMContext *ctx = avctx->priv_data;
228+ int i;
229+ int16_t *ref_dst = ctx->ref_buf + 120;
230+ int *lar = ctx->lar[ctx->lar_idx];
231+ lar[0] = decode_log_area(get_bits(gb, 6), 13107, 1 << 15);
232+ lar[1] = decode_log_area(get_bits(gb, 6), 13107, 1 << 15);
233+ lar[2] = decode_log_area(get_bits(gb, 5), 13107, (1 << 14) + 2048*2);
234+ lar[3] = decode_log_area(get_bits(gb, 5), 13107, (1 << 14) - 2560*2);
235+ lar[4] = decode_log_area(get_bits(gb, 4), 19223, (1 << 13) + 94*2);
236+ lar[5] = decode_log_area(get_bits(gb, 4), 17476, (1 << 13) - 1792*2);
237+ lar[6] = decode_log_area(get_bits(gb, 3), 31454, (1 << 12) - 341*2);
238+ lar[7] = decode_log_area(get_bits(gb, 3), 29708, (1 << 12) - 1144*2);
239+
240+ for (i = 0; i < 4; i++) {
241+ int lag = get_bits(gb, 7);
242+ int gain_idx = get_bits(gb, 2);
243+ int offset = get_bits(gb, 2);
244+ lag = av_clip(lag, 40, 120);
245+ long_term_synth(ref_dst, lag, gain_idx);
246+ apcm_dequant_add(gb, ref_dst + offset);
247+ ref_dst += 40;
248+ }
249+ memcpy(ctx->ref_buf, ctx->ref_buf + 160, 120 * sizeof(*ctx->ref_buf));
250+ short_term_synth(ctx, samples, ctx->ref_buf + 120);
251+ // for optimal speed this could be merged with short_term_synth,
252+ // not done yet because it is a bit ugly
253+ ctx->msr = postprocess(samples, ctx->msr);
254+ return 0;
255+}
256+
257+static int gsm_decode_frame(AVCodecContext *avctx, void *data,
258+ int *data_size, AVPacket *avpkt)
259+{
260+ int res;
261+ GetBitContext gb;
262+ const uint8_t *buf = avpkt->data;
263+ int buf_size = avpkt->size;
264+ int16_t *samples = data;
265+ int frame_bytes = 2 * avctx->frame_size;
266+
267+ if (*data_size < frame_bytes)
268+ return -1;
269+ *data_size = 0;
270+ if(buf_size < avctx->block_align)
271+ return AVERROR_INVALIDDATA;
272+ init_get_bits(&gb, buf, buf_size * 8);
273+
274+ switch (avctx->codec_id) {
275+ case CODEC_ID_GSM:
276+ if (get_bits(&gb, 4) != 0xd)
277+ av_log(avctx, AV_LOG_WARNING, "Missing GSM magic!\n");
278+ res = gsm_decode_block(avctx, samples, &gb);
279+ if (res < 0)
280+ return res;
281+ break;
282+ case CODEC_ID_GSM_MS:
283+ res = gsm_decode_block(avctx, samples, &gb);
284+ if (res < 0)
285+ return res;
286+ res = gsm_decode_block(avctx, samples + GSM_FRAME_SIZE, &gb);
287+ if (res < 0)
288+ return res;
289+ }
290+ *data_size = frame_bytes;
291+ return avctx->block_align;
292+}
293+
294+AVCodec gsm_decoder = {
295+ "gsm",
296+ AVMEDIA_TYPE_AUDIO,
297+ CODEC_ID_GSM,
298+ sizeof(GSMContext),
299+ gsm_init,
300+ NULL,
301+ NULL,
302+ gsm_decode_frame,
303+ .long_name = NULL_IF_CONFIG_SMALL("GSM"),
304+};
305+
306+AVCodec gsm_ms_decoder = {
307+ "gsm_ms",
308+ AVMEDIA_TYPE_AUDIO,
309+ CODEC_ID_GSM_MS,
310+ sizeof(GSMContext),
311+ gsm_init,
312+ NULL,
313+ NULL,
314+ gsm_decode_frame,
315+ .long_name = NULL_IF_CONFIG_SMALL("GSM Microsoft variant"),
316+};

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