summaryrefslogtreecommitdiffstats
path: root/wsutil/g711.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 20:34:10 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 20:34:10 +0000
commite4ba6dbc3f1e76890b22773807ea37fe8fa2b1bc (patch)
tree68cb5ef9081156392f1dd62a00c6ccc1451b93df /wsutil/g711.c
parentInitial commit. (diff)
downloadwireshark-e4ba6dbc3f1e76890b22773807ea37fe8fa2b1bc.tar.xz
wireshark-e4ba6dbc3f1e76890b22773807ea37fe8fa2b1bc.zip
Adding upstream version 4.2.2.upstream/4.2.2
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'wsutil/g711.c')
-rw-r--r--wsutil/g711.c300
1 files changed, 300 insertions, 0 deletions
diff --git a/wsutil/g711.c b/wsutil/g711.c
new file mode 100644
index 00000000..e6c3dcae
--- /dev/null
+++ b/wsutil/g711.c
@@ -0,0 +1,300 @@
+/*
+ * 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
+ */
+
+#include "g711.h"
+
+/*
+ * 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 */
+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};
+
+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.
+ */
+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
+ *
+ */
+int
+alaw2linear(
+ unsigned char a_val)
+{
+ int t;
+ int seg;
+ /*printf(" vrednost a_val %X ", a_val);*/
+ 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;
+ }
+ /*printf("izracunan int %d in njegov hex %X \n", t,t);*/
+ 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.
+ */
+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.
+ */
+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)));
+ * }
+ */
+
+/*
+ * Editor modelines - https://www.wireshark.org/tools/modelines.html
+ *
+ * Local variables:
+ * c-basic-offset: 8
+ * tab-width: 8
+ * indent-tabs-mode: t
+ * End:
+ *
+ * vi: set shiftwidth=8 tabstop=8 noexpandtab:
+ * :indentSize=8:tabSize=8:noTabs=false:
+ */