[SCM] libav/experimental: Add a G.722 encoder
siretart at users.alioth.debian.org
siretart at users.alioth.debian.org
Sun Jun 30 17:16:03 UTC 2013
The following commit has been merged in the experimental branch:
commit 21e681ba57735bca225f1f903c7e93ffdb0f86ba
Author: Martin Storsjö <martin at martin.st>
Date: Thu Sep 23 21:33:29 2010 +0000
Add a G.722 encoder
Originally committed as revision 25164 to svn://svn.ffmpeg.org/ffmpeg/trunk
diff --git a/Changelog b/Changelog
index 503ac43..682d399 100644
--- a/Changelog
+++ b/Changelog
@@ -33,7 +33,7 @@ version <next>:
- Apple HTTP Live Streaming demuxer
- a64 codec
- MMS-HTTP support
-- G.722 ADPCM audio decoder
+- G.722 ADPCM audio encoder/decoder
- R10k video decoder
- ocv_smooth filter
diff --git a/doc/general.texi b/doc/general.texi
index 9a3200f..b9953cc 100644
--- a/doc/general.texi
+++ b/doc/general.texi
@@ -536,7 +536,7 @@ following image formats are supported:
@item ADPCM Electronic Arts R2 @tab @tab X
@item ADPCM Electronic Arts R3 @tab @tab X
@item ADPCM Electronic Arts XAS @tab @tab X
- at item ADPCM G.722 @tab @tab X
+ at item ADPCM G.722 @tab X @tab X
@item ADPCM G.726 @tab X @tab X
@item ADPCM IMA AMV @tab @tab X
@tab Used in AMV files
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index a9bb529..83aece2 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -477,6 +477,7 @@ OBJS-$(CONFIG_ADPCM_EA_R2_DECODER) += adpcm.o
OBJS-$(CONFIG_ADPCM_EA_R3_DECODER) += adpcm.o
OBJS-$(CONFIG_ADPCM_EA_XAS_DECODER) += adpcm.o
OBJS-$(CONFIG_ADPCM_G722_DECODER) += g722.o
+OBJS-$(CONFIG_ADPCM_G722_ENCODER) += g722.o
OBJS-$(CONFIG_ADPCM_G726_DECODER) += g726.o
OBJS-$(CONFIG_ADPCM_G726_ENCODER) += g726.o
OBJS-$(CONFIG_ADPCM_IMA_AMV_DECODER) += adpcm.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index bc8831f..d499f25 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -318,7 +318,7 @@ void avcodec_register_all(void)
REGISTER_DECODER (ADPCM_EA_R2, adpcm_ea_r2);
REGISTER_DECODER (ADPCM_EA_R3, adpcm_ea_r3);
REGISTER_DECODER (ADPCM_EA_XAS, adpcm_ea_xas);
- REGISTER_DECODER (ADPCM_G722, adpcm_g722);
+ REGISTER_ENCDEC (ADPCM_G722, adpcm_g722);
REGISTER_ENCDEC (ADPCM_G726, adpcm_g726);
REGISTER_DECODER (ADPCM_IMA_AMV, adpcm_ima_amv);
REGISTER_DECODER (ADPCM_IMA_DK3, adpcm_ima_dk3);
diff --git a/libavcodec/g722.c b/libavcodec/g722.c
index 8707d16..51a0f39 100644
--- a/libavcodec/g722.c
+++ b/libavcodec/g722.c
@@ -1,5 +1,5 @@
/*
- * G.722 ADPCM audio decoder
+ * G.722 ADPCM audio encoder/decoder
*
* Copyright (c) CMU 1993 Computer Science, Speech Group
* Chengxiang Lu and Alex Hauptmann
@@ -219,6 +219,7 @@ static av_cold int g722_init(AVCodecContext * avctx)
return 0;
}
+#if CONFIG_ADPCM_G722_DECODER
static const int16_t low_inv_quant5[32] = {
-35, -35, -2919, -2195, -1765, -1458, -1219, -1023,
-858, -714, -587, -473, -370, -276, -190, -110,
@@ -301,4 +302,84 @@ AVCodec adpcm_g722_decoder = {
.long_name = NULL_IF_CONFIG_SMALL("G.722 ADPCM"),
.max_lowres = 1,
};
+#endif
+
+#if CONFIG_ADPCM_G722_ENCODER
+static const int16_t low_quant[33] = {
+ 35, 72, 110, 150, 190, 233, 276, 323,
+ 370, 422, 473, 530, 587, 650, 714, 786,
+ 858, 940, 1023, 1121, 1219, 1339, 1458, 1612,
+ 1765, 1980, 2195, 2557, 2919
+};
+
+static inline void filter_samples(G722Context *c, const int16_t *samples,
+ int *xlow, int *xhigh)
+{
+ int xout1, xout2;
+ c->prev_samples[c->prev_samples_pos++] = samples[0];
+ c->prev_samples[c->prev_samples_pos++] = samples[1];
+ apply_qmf(c->prev_samples + c->prev_samples_pos - 24, &xout1, &xout2);
+ *xlow = xout1 + xout2 >> 13;
+ *xhigh = xout1 - xout2 >> 13;
+ if (c->prev_samples_pos >= PREV_SAMPLES_BUF_SIZE) {
+ memmove(c->prev_samples,
+ c->prev_samples + c->prev_samples_pos - 22,
+ 22 * sizeof(c->prev_samples[0]));
+ c->prev_samples_pos = 22;
+ }
+}
+
+static inline int encode_high(const struct G722Band *state, int xhigh)
+{
+ int diff = av_clip_int16(xhigh - state->s_predictor);
+ int pred = 141 * state->scale_factor >> 8;
+ /* = diff >= 0 ? (diff < pred) + 2 : diff >= -pred */
+ return ((diff ^ (diff >> (sizeof(diff)*8-1))) < pred) + 2*(diff >= 0);
+}
+
+static inline int encode_low(const struct G722Band* state, int xlow)
+{
+ int diff = av_clip_int16(xlow - state->s_predictor);
+ /* = diff >= 0 ? diff : -(diff + 1) */
+ int limit = diff ^ (diff >> (sizeof(diff)*8-1));
+ int i = 0;
+ limit = limit + 1 << 10;
+ if (limit > low_quant[8] * state->scale_factor)
+ i = 9;
+ while (i < 29 && limit > low_quant[i] * state->scale_factor)
+ i++;
+ return (diff < 0 ? (i < 2 ? 63 : 33) : 61) - i;
+}
+
+static int g722_encode_frame(AVCodecContext *avctx,
+ uint8_t *dst, int buf_size, void *data)
+{
+ G722Context *c = avctx->priv_data;
+ const int16_t *samples = data;
+ int i;
+
+ for (i = 0; i < buf_size >> 1; i++) {
+ int xlow, xhigh, ihigh, ilow;
+ filter_samples(c, &samples[2*i], &xlow, &xhigh);
+ ihigh = encode_high(&c->band[1], xhigh);
+ ilow = encode_low(&c->band[0], xlow);
+ update_high_predictor(&c->band[1], c->band[1].scale_factor *
+ high_inv_quant[ihigh] >> 10, ihigh);
+ update_low_predictor(&c->band[0], ilow >> 2);
+ *dst++ = ihigh << 6 | ilow;
+ }
+ return i;
+}
+
+AVCodec adpcm_g722_encoder = {
+ .name = "g722",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .id = CODEC_ID_ADPCM_G722,
+ .priv_data_size = sizeof(G722Context),
+ .init = g722_init,
+ .encode = g722_encode_frame,
+ .long_name = NULL_IF_CONFIG_SMALL("G.722 ADPCM"),
+ .sample_fmts = (enum SampleFormat[]){SAMPLE_FMT_S16,SAMPLE_FMT_NONE},
+};
+#endif
--
Libav/FFmpeg packaging
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