diff options
Diffstat (limited to 'pjmedia/src/pjmedia/g711.c')
| -rw-r--r-- | pjmedia/src/pjmedia/g711.c | 600 |
1 files changed, 600 insertions, 0 deletions
diff --git a/pjmedia/src/pjmedia/g711.c b/pjmedia/src/pjmedia/g711.c new file mode 100644 index 00000000..55ced1b9 --- /dev/null +++ b/pjmedia/src/pjmedia/g711.c @@ -0,0 +1,600 @@ +/* $Header: /pjproject-0.3/pjmedia/src/pjmedia/g711.c 5 10/14/05 12:23a Bennylp $ */
+/* This file contains file from Sun Microsystems, Inc, with the complete
+ * copyright notice in the second half of this file.
+ */
+#include <pjmedia/codec.h>
+#include <pj/pool.h>
+#include <pj/string.h>
+#include <string.h> /* memset */
+
+#define G711_BPS 64000
+#define G711_CODEC_CNT 0 /* number of codec to preallocate in memory */
+
+/* These are the only public functions exported to applications */
+PJ_DECL(pj_status_t) g711_init_factory (pj_codec_factory *factory, pj_pool_t *pool);
+PJ_DECL(pj_status_t) g711_deinit_factory (pj_codec_factory *factory);
+
+/* Algorithm prototypes. */
+static unsigned char linear2alaw(int pcm_val); /* 2's complement (16-bit range) */
+static int alaw2linear(unsigned char a_val);
+static unsigned char linear2ulaw(int pcm_val);
+static int ulaw2linear(unsigned char u_val);
+
+/* Prototypes for G711 factory */
+static pj_status_t g711_match_id( pj_codec_factory *factory, const pj_codec_id *id );
+static pj_status_t g711_default_attr( pj_codec_factory *factory, const pj_codec_id *id, pj_codec_attr *attr );
+static unsigned g711_enum_codecs (pj_codec_factory *factory, unsigned count, pj_codec_id codecs[]);
+static pj_codec* g711_alloc_codec( pj_codec_factory *factory, const pj_codec_id *id);
+static void g711_dealloc_codec( pj_codec_factory *factory, pj_codec *codec );
+
+/* Prototypes for G711 implementation. */
+static pj_status_t g711_codec_default_attr (pj_codec *codec, pj_codec_attr *attr);
+static pj_status_t g711_init( pj_codec *codec, pj_pool_t *pool );
+static pj_status_t g711_open( pj_codec *codec, pj_codec_attr *attr );
+static pj_status_t g711_close( pj_codec *codec );
+static pj_status_t g711_encode( pj_codec *codec, const struct pj_audio_frame *input,
+ unsigned output_buf_len, struct pj_audio_frame *output);
+static pj_status_t g711_decode( pj_codec *codec, const struct pj_audio_frame *input,
+ unsigned output_buf_len, struct pj_audio_frame *output);
+
+/* Definition for G711 codec operations. */
+static pj_codec_op g711_op =
+{
+ &g711_codec_default_attr ,
+ &g711_init,
+ &g711_open,
+ &g711_close,
+ &g711_encode,
+ &g711_decode
+};
+
+/* Definition for G711 codec factory operations. */
+static pj_codec_factory_op g711_factory_op =
+{
+ &g711_match_id,
+ &g711_default_attr,
+ &g711_enum_codecs,
+ &g711_alloc_codec,
+ &g711_dealloc_codec
+};
+
+/* G711 factory private data */
+struct g711_factory_private
+{
+ pj_pool_t *pool;
+ pj_codec codec_list;
+};
+
+/* G711 codec private data. */
+struct g711_private
+{
+ unsigned pt;
+};
+
+
+PJ_DEF(pj_status_t) g711_init_factory (pj_codec_factory *factory, pj_pool_t *pool)
+{
+ struct g711_factory_private *priv;
+ //enum { CODEC_MEM_SIZE = sizeof(pj_codec) + sizeof(struct g711_private) + 4 };
+
+ /* Create pool. */
+ /*
+ pool = pj_pool_pool_create_pool(pp, "g711ftry",
+ G711_CODEC_CNT*CODEC_MEM_SIZE +
+ sizeof(struct g711_factory_private),
+ CODEC_MEM_SIZE, NULL);
+ if (!pool)
+ return -1;
+ */
+
+ priv = pj_pool_alloc(pool, sizeof(struct g711_factory_private));
+ if (!priv)
+ return -1;
+
+ factory->factory_data = priv;
+ factory->op = &g711_factory_op;
+
+ priv->pool = pool;
+ pj_list_init(&priv->codec_list);
+ return 0;
+}
+
+PJ_DEF(pj_status_t) g711_deinit_factory (pj_codec_factory *factory)
+{
+ struct g711_factory_private *priv = factory->factory_data;
+
+ /* Invalidate member to help detect errors */
+ priv->pool = NULL;
+ priv->codec_list.next = priv->codec_list.prev = NULL;
+ return 0;
+}
+
+static pj_status_t g711_match_id( pj_codec_factory *factory, const pj_codec_id *id )
+{
+ PJ_UNUSED_ARG(factory)
+
+ /* It's sufficient to check payload type only. */
+ return (id->pt==PJ_RTP_PT_PCMU || id->pt==PJ_RTP_PT_PCMA) ? 0 : -1;
+}
+
+static pj_status_t g711_default_attr (pj_codec_factory *factory,
+ const pj_codec_id *id,
+ pj_codec_attr *attr )
+{
+ PJ_UNUSED_ARG(factory)
+
+ memset(attr, 0, sizeof(pj_codec_attr));
+ attr->sample_rate = 8000;
+ attr->avg_bps = G711_BPS;
+ attr->pcm_bits_per_sample = 16;
+ attr->ptime = 20;
+ attr->pt = id->pt;
+
+ /* Default all flag bits disabled. */
+
+ return PJ_SUCCESS;
+}
+
+static unsigned g711_enum_codecs (pj_codec_factory *factory,
+ unsigned count, pj_codec_id codecs[])
+{
+ PJ_UNUSED_ARG(factory)
+
+ if (count > 0) {
+ codecs[0].type = PJ_MEDIA_TYPE_AUDIO;
+ codecs[0].pt = PJ_RTP_PT_PCMU;
+ codecs[0].encoding_name = pj_str("PCMU");
+ codecs[0].sample_rate = 8000;
+ }
+ if (count > 1) {
+ codecs[1].type = PJ_MEDIA_TYPE_AUDIO;
+ codecs[1].pt = PJ_RTP_PT_PCMA;
+ codecs[1].encoding_name = pj_str("PCMA");
+ codecs[1].sample_rate = 8000;
+ }
+
+ return 2;
+}
+
+static pj_codec *g711_alloc_codec( pj_codec_factory *factory, const pj_codec_id *id)
+{
+ struct g711_factory_private *priv = factory->factory_data;
+ pj_codec *codec = NULL;
+
+ /* Allocate new codec if no more is available */
+ if (pj_list_empty(&priv->codec_list)) {
+ struct g711_private *codec_priv;
+
+ codec = pj_pool_alloc(priv->pool, sizeof(pj_codec));
+ codec_priv = pj_pool_alloc(priv->pool, sizeof(struct g711_private));
+ if (!codec || !codec_priv)
+ return NULL;
+
+ codec_priv->pt = id->pt;
+
+ codec->factory = factory;
+ codec->op = &g711_op;
+ codec->codec_data = codec_priv;
+ } else {
+ codec = priv->codec_list.next;
+ pj_list_erase(codec);
+ }
+
+ /* Zero the list, for error detection in g711_dealloc_codec */
+ codec->next = codec->prev = NULL;
+
+ return codec;
+}
+
+static void g711_dealloc_codec( pj_codec_factory *factory, pj_codec *codec )
+{
+ struct g711_factory_private *priv = factory->factory_data;
+
+ /* Check that this node has not been deallocated before */
+ pj_assert (codec->next==NULL && codec->prev==NULL);
+ if (codec->next!=NULL || codec->prev!=NULL) {
+ return;
+ }
+
+ /* Insert at the back of the list */
+ pj_list_insert_before(&priv->codec_list, codec);
+}
+
+static pj_status_t g711_codec_default_attr (pj_codec *codec, pj_codec_attr *attr)
+{
+ struct g711_private *priv = codec->codec_data;
+ pj_codec_id id;
+
+ id.pt = priv->pt;
+ return g711_default_attr (NULL, &id, attr);
+}
+
+static pj_status_t g711_init( pj_codec *codec, pj_pool_t *pool )
+{
+ /* There's nothing to do here really */
+ PJ_UNUSED_ARG(codec)
+ PJ_UNUSED_ARG(pool)
+
+ return PJ_SUCCESS;
+}
+
+static pj_status_t g711_open( pj_codec *codec, pj_codec_attr *attr )
+{
+ struct g711_private *priv = codec->codec_data;
+ priv->pt = attr->pt;
+ return PJ_SUCCESS;
+}
+
+static pj_status_t g711_close( pj_codec *codec )
+{
+ PJ_UNUSED_ARG(codec);
+ /* Nothing to do */
+ return PJ_SUCCESS;
+}
+
+static pj_status_t g711_encode( pj_codec *codec, const struct pj_audio_frame *input,
+ unsigned output_buf_len, struct pj_audio_frame *output)
+{
+ pj_int16_t *samples = (pj_int16_t*) input->buf;
+ struct g711_private *priv = codec->codec_data;
+
+ /* Check output buffer length */
+ if (output_buf_len < input->size / 2)
+ return -1;
+
+ /* Encode */
+ if (priv->pt == PJ_RTP_PT_PCMA) {
+ unsigned i;
+ pj_uint8_t *dst = output->buf;
+
+ for (i=0; i!=input->size/2; ++i, ++dst) {
+ *dst = linear2alaw(samples[i]);
+ }
+ } else if (priv->pt == PJ_RTP_PT_PCMU) {
+ unsigned i;
+ pj_uint8_t *dst = output->buf;
+
+ for (i=0; i!=input->size/2; ++i, ++dst) {
+ *dst = linear2ulaw(samples[i]);
+ }
+
+ } else {
+ return -1;
+ }
+
+ output->type = PJ_AUDIO_FRAME_AUDIO;
+ output->size = input->size / 2;
+
+ return 0;
+}
+
+static pj_status_t g711_decode( pj_codec *codec, const struct pj_audio_frame *input,
+ unsigned output_buf_len, struct pj_audio_frame *output)
+{
+ struct g711_private *priv = codec->codec_data;
+
+ /* Check output buffer length */
+ if (output_buf_len < input->size * 2)
+ return -1;
+
+ /* Decode */
+ if (priv->pt == PJ_RTP_PT_PCMA) {
+ unsigned i;
+ pj_uint8_t *src = input->buf;
+ pj_uint16_t *dst = output->buf;
+
+ for (i=0; i!=input->size; ++i) {
+ *dst++ = (pj_uint16_t) alaw2linear(*src++);
+ }
+ } else if (priv->pt == PJ_RTP_PT_PCMU) {
+ unsigned i;
+ pj_uint8_t *src = input->buf;
+ pj_uint16_t *dst = output->buf;
+
+ for (i=0; i!=input->size; ++i) {
+ *dst++ = (pj_uint16_t) ulaw2linear(*src++);
+ }
+
+ } else {
+ return -1;
+ }
+
+ output->type = PJ_AUDIO_FRAME_AUDIO;
+ output->size = input->size * 2;
+
+ return 0;
+}
+
+
+/*
+ * This source code is a product of Sun Microsystems, Inc. and is provided
+ * for unrestricted use. Users may copy or modify this source code without
+ * charge.
+ *
+ * SUN SOURCE CODE IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING
+ * THE WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
+ *
+ * Sun source code is provided with no support and without any obligation on
+ * the part of Sun Microsystems, Inc. to assist in its use, correction,
+ * modification or enhancement.
+ *
+ * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
+ * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY THIS SOFTWARE
+ * OR ANY PART THEREOF.
+ *
+ * In no event will Sun Microsystems, Inc. be liable for any lost revenue
+ * or profits or other special, indirect and consequential damages, even if
+ * Sun has been advised of the possibility of such damages.
+ *
+ * Sun Microsystems, Inc.
+ * 2550 Garcia Avenue
+ * Mountain View, California 94043
+ */
+
+
+
+#ifdef _MSC_VER
+# pragma warning ( disable: 4244 ) /* Conversion from int to char etc */
+#endif
+
+/*
+ * g711.c
+ *
+ * u-law, A-law and linear PCM conversions.
+ */
+#define SIGN_BIT (0x80) /* Sign bit for a A-law byte. */
+#define QUANT_MASK (0xf) /* Quantization field mask. */
+#define NSEGS (8) /* Number of A-law segments. */
+#define SEG_SHIFT (4) /* Left shift for segment number. */
+#define SEG_MASK (0x70) /* Segment field mask. */
+
+static short seg_end[8] = {0xFF, 0x1FF, 0x3FF, 0x7FF,
+ 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF};
+
+/* copy from CCITT G.711 specifications */
+static unsigned char _u2a[128] = { /* u- to A-law conversions */
+ 1, 1, 2, 2, 3, 3, 4, 4,
+ 5, 5, 6, 6, 7, 7, 8, 8,
+ 9, 10, 11, 12, 13, 14, 15, 16,
+ 17, 18, 19, 20, 21, 22, 23, 24,
+ 25, 27, 29, 31, 33, 34, 35, 36,
+ 37, 38, 39, 40, 41, 42, 43, 44,
+ 46, 48, 49, 50, 51, 52, 53, 54,
+ 55, 56, 57, 58, 59, 60, 61, 62,
+ 64, 65, 66, 67, 68, 69, 70, 71,
+ 72, 73, 74, 75, 76, 77, 78, 79,
+ 81, 82, 83, 84, 85, 86, 87, 88,
+ 89, 90, 91, 92, 93, 94, 95, 96,
+ 97, 98, 99, 100, 101, 102, 103, 104,
+ 105, 106, 107, 108, 109, 110, 111, 112,
+ 113, 114, 115, 116, 117, 118, 119, 120,
+ 121, 122, 123, 124, 125, 126, 127, 128};
+
+static unsigned char _a2u[128] = { /* A- to u-law conversions */
+ 1, 3, 5, 7, 9, 11, 13, 15,
+ 16, 17, 18, 19, 20, 21, 22, 23,
+ 24, 25, 26, 27, 28, 29, 30, 31,
+ 32, 32, 33, 33, 34, 34, 35, 35,
+ 36, 37, 38, 39, 40, 41, 42, 43,
+ 44, 45, 46, 47, 48, 48, 49, 49,
+ 50, 51, 52, 53, 54, 55, 56, 57,
+ 58, 59, 60, 61, 62, 63, 64, 64,
+ 65, 66, 67, 68, 69, 70, 71, 72,
+ 73, 74, 75, 76, 77, 78, 79, 79,
+ 80, 81, 82, 83, 84, 85, 86, 87,
+ 88, 89, 90, 91, 92, 93, 94, 95,
+ 96, 97, 98, 99, 100, 101, 102, 103,
+ 104, 105, 106, 107, 108, 109, 110, 111,
+ 112, 113, 114, 115, 116, 117, 118, 119,
+ 120, 121, 122, 123, 124, 125, 126, 127};
+
+static int
+search(
+ int val,
+ short *table,
+ int size)
+{
+ int i;
+
+ for (i = 0; i < size; i++) {
+ if (val <= *table++)
+ return (i);
+ }
+ return (size);
+}
+
+/*
+ * linear2alaw() - Convert a 16-bit linear PCM value to 8-bit A-law
+ *
+ * linear2alaw() accepts an 16-bit integer and encodes it as A-law data.
+ *
+ * Linear Input Code Compressed Code
+ * ------------------------ ---------------
+ * 0000000wxyza 000wxyz
+ * 0000001wxyza 001wxyz
+ * 000001wxyzab 010wxyz
+ * 00001wxyzabc 011wxyz
+ * 0001wxyzabcd 100wxyz
+ * 001wxyzabcde 101wxyz
+ * 01wxyzabcdef 110wxyz
+ * 1wxyzabcdefg 111wxyz
+ *
+ * For further information see John C. Bellamy's Digital Telephony, 1982,
+ * John Wiley & Sons, pps 98-111 and 472-476.
+ */
+static unsigned char
+linear2alaw(
+ int pcm_val) /* 2's complement (16-bit range) */
+{
+ int mask;
+ int seg;
+ unsigned char aval;
+
+ if (pcm_val >= 0) {
+ mask = 0xD5; /* sign (7th) bit = 1 */
+ } else {
+ mask = 0x55; /* sign bit = 0 */
+ pcm_val = -pcm_val - 8;
+ }
+
+ /* Convert the scaled magnitude to segment number. */
+ seg = search(pcm_val, seg_end, 8);
+
+ /* Combine the sign, segment, and quantization bits. */
+
+ if (seg >= 8) /* out of range, return maximum value. */
+ return (0x7F ^ mask);
+ else {
+ aval = seg << SEG_SHIFT;
+ if (seg < 2)
+ aval |= (pcm_val >> 4) & QUANT_MASK;
+ else
+ aval |= (pcm_val >> (seg + 3)) & QUANT_MASK;
+ return (aval ^ mask);
+ }
+}
+
+/*
+ * alaw2linear() - Convert an A-law value to 16-bit linear PCM
+ *
+ */
+static int
+alaw2linear(
+ unsigned char a_val)
+{
+ int t;
+ int seg;
+
+ a_val ^= 0x55;
+
+ t = (a_val & QUANT_MASK) << 4;
+ seg = ((unsigned)a_val & SEG_MASK) >> SEG_SHIFT;
+ switch (seg) {
+ case 0:
+ t += 8;
+ break;
+ case 1:
+ t += 0x108;
+ break;
+ default:
+ t += 0x108;
+ t <<= seg - 1;
+ }
+ return ((a_val & SIGN_BIT) ? t : -t);
+}
+
+#define BIAS (0x84) /* Bias for linear code. */
+
+/*
+ * linear2ulaw() - Convert a linear PCM value to u-law
+ *
+ * In order to simplify the encoding process, the original linear magnitude
+ * is biased by adding 33 which shifts the encoding range from (0 - 8158) to
+ * (33 - 8191). The result can be seen in the following encoding table:
+ *
+ * Biased Linear Input Code Compressed Code
+ * ------------------------ ---------------
+ * 00000001wxyza 000wxyz
+ * 0000001wxyzab 001wxyz
+ * 000001wxyzabc 010wxyz
+ * 00001wxyzabcd 011wxyz
+ * 0001wxyzabcde 100wxyz
+ * 001wxyzabcdef 101wxyz
+ * 01wxyzabcdefg 110wxyz
+ * 1wxyzabcdefgh 111wxyz
+ *
+ * Each biased linear code has a leading 1 which identifies the segment
+ * number. The value of the segment number is equal to 7 minus the number
+ * of leading 0's. The quantization interval is directly available as the
+ * four bits wxyz. * The trailing bits (a - h) are ignored.
+ *
+ * Ordinarily the complement of the resulting code word is used for
+ * transmission, and so the code word is complemented before it is returned.
+ *
+ * For further information see John C. Bellamy's Digital Telephony, 1982,
+ * John Wiley & Sons, pps 98-111 and 472-476.
+ */
+static unsigned char
+linear2ulaw(
+ int pcm_val) /* 2's complement (16-bit range) */
+{
+ int mask;
+ int seg;
+ unsigned char uval;
+
+ /* Get the sign and the magnitude of the value. */
+ if (pcm_val < 0) {
+ pcm_val = BIAS - pcm_val;
+ mask = 0x7F;
+ } else {
+ pcm_val += BIAS;
+ mask = 0xFF;
+ }
+
+ /* Convert the scaled magnitude to segment number. */
+ seg = search(pcm_val, seg_end, 8);
+
+ /*
+ * Combine the sign, segment, quantization bits;
+ * and complement the code word.
+ */
+ if (seg >= 8) /* out of range, return maximum value. */
+ return (0x7F ^ mask);
+ else {
+ uval = (seg << 4) | ((pcm_val >> (seg + 3)) & 0xF);
+ return (uval ^ mask);
+ }
+
+}
+
+/*
+ * ulaw2linear() - Convert a u-law value to 16-bit linear PCM
+ *
+ * First, a biased linear code is derived from the code word. An unbiased
+ * output can then be obtained by subtracting 33 from the biased code.
+ *
+ * Note that this function expects to be passed the complement of the
+ * original code word. This is in keeping with ISDN conventions.
+ */
+static int
+ulaw2linear(
+ unsigned char u_val)
+{
+ int t;
+
+ /* Complement to obtain normal u-law value. */
+ u_val = ~u_val;
+
+ /*
+ * Extract and bias the quantization bits. Then
+ * shift up by the segment number and subtract out the bias.
+ */
+ t = ((u_val & QUANT_MASK) << 3) + BIAS;
+ t <<= ((unsigned)u_val & SEG_MASK) >> SEG_SHIFT;
+
+ return ((u_val & SIGN_BIT) ? (BIAS - t) : (t - BIAS));
+}
+
+/* A-law to u-law conversion */
+unsigned char
+alaw2ulaw(
+ unsigned char aval)
+{
+ aval &= 0xff;
+ return ((aval & 0x80) ? (0xFF ^ _a2u[aval ^ 0xD5]) :
+ (0x7F ^ _a2u[aval ^ 0x55]));
+}
+
+/* u-law to A-law conversion */
+unsigned char
+ulaw2alaw(
+ unsigned char uval)
+{
+ uval &= 0xff;
+ return ((uval & 0x80) ? (0xD5 ^ (_u2a[0xFF ^ uval] - 1)) :
+ (0x55 ^ (_u2a[0x7F ^ uval] - 1)));
+}
+
+
+
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