[Asterisk-cvs] asterisk/formats format_vox.c,1.12,1.13
markster at lists.digium.com
markster at lists.digium.com
Thu Mar 11 15:04:04 CST 2004
Update of /usr/cvsroot/asterisk/formats
In directory mongoose.digium.com:/tmp/cvs-serv30275/formats
Modified Files:
format_vox.c
Log Message:
Make ADPCM frames standard
Index: format_vox.c
===================================================================
RCS file: /usr/cvsroot/asterisk/formats/format_vox.c,v
retrieving revision 1.12
retrieving revision 1.13
diff -u -d -r1.12 -r1.13
--- format_vox.c 2 Oct 2003 23:17:32 -0000 1.12
+++ format_vox.c 11 Mar 2004 19:57:10 -0000 1.13
@@ -33,7 +33,6 @@
#endif
#define BUF_SIZE 80 /* 160 samples */
-#define BUF_SHIFT 5
struct ast_filestream {
void *reserved[AST_RESERVED_POINTERS];
@@ -42,7 +41,7 @@
struct ast_frame fr; /* Frame information */
char waste[AST_FRIENDLY_OFFSET]; /* Buffer for sending frames, etc */
char empty; /* Empty character */
- unsigned char buf[BUF_SIZE + BUF_SHIFT]; /* Output Buffer */
+ unsigned char buf[BUF_SIZE]; /* Output Buffer */
int lasttimeout;
struct timeval last;
short signal; /* Signal level (file side) */
@@ -59,143 +58,6 @@
static char *desc = "Dialogic VOX (ADPCM) File Format";
static char *exts = "vox";
-/*
- * Step size index shift table
- */
-
-static short indsft[8] = { -1, -1, -1, -1, 2, 4, 6, 8 };
-
-/*
- * Step size table, where stpsz[i]=floor[16*(11/10)^i]
- */
-
-static short stpsz[49] = {
- 16, 17, 19, 21, 23, 25, 28, 31, 34, 37, 41, 45, 50, 55, 60, 66, 73,
- 80, 88, 97, 107, 118, 130, 143, 157, 173, 190, 209, 230, 253, 279,
- 307, 337, 371, 408, 449, 494, 544, 598, 658, 724, 796, 876, 963,
- 1060, 1166, 1282, 1411, 1552
-};
-
-/*
- * Nibble to bit map
- */
-
-static short nbl2bit[16][4] = {
- {1, 0, 0, 0}, {1, 0, 0, 1}, {1, 0, 1, 0}, {1, 0, 1, 1},
- {1, 1, 0, 0}, {1, 1, 0, 1}, {1, 1, 1, 0}, {1, 1, 1, 1},
- {-1, 0, 0, 0}, {-1, 0, 0, 1}, {-1, 0, 1, 0}, {-1, 0, 1, 1},
- {-1, 1, 0, 0}, {-1, 1, 0, 1}, {-1, 1, 1, 0}, {-1, 1, 1, 1}
-};
-
-/*
- * Decode(encoded)
- * Decodes the encoded nibble from the adpcm file.
- *
- * Results:
- * Returns the encoded difference.
- *
- * Side effects:
- * Sets the index to the step size table for the next encode.
- */
-
-static inline void
-decode (unsigned char encoded, short *ssindex, short *signal, unsigned char *rkey, unsigned char *next)
-{
- short diff, step;
- step = stpsz[*ssindex];
-
- diff = step * nbl2bit[encoded][1] +
- (step >> 1) * nbl2bit[encoded][2] +
- (step >> 2) * nbl2bit[encoded][3] +
- (step >> 3);
- if (nbl2bit[encoded][2] && (step & 0x1))
- diff++;
- diff *= nbl2bit[encoded][0];
-
- if ( *next & 0x1 )
- *signal -= 8;
- else if ( *next & 0x2 )
- *signal += 8;
-
- *signal += diff;
-
- if (*signal > 2047)
- *signal = 2047;
- else if (*signal < -2047)
- *signal = -2047;
-
- *next = 0;
- if( encoded & 0x7 )
- *rkey = 0;
- else if ( ++(*rkey) == 24 ) {
- *rkey = 0;
- if (*signal > 0)
- *next = 0x1;
- else if (*signal < 0)
- *next = 0x2;
- }
-
- *ssindex = *ssindex + indsft[(encoded & 7)];
- if (*ssindex < 0)
- *ssindex = 0;
- else if (*ssindex > 48)
- *ssindex = 48;
-}
-
-/*
- * Adpcm
- * Takes a signed linear signal and encodes it as ADPCM
- * For more information see http://support.dialogic.com/appnotes/adpcm.pdf
- *
- * Results:
- * Foo.
- *
- * Side effects:
- * signal gets updated with each pass.
- */
-
-static inline unsigned char
-adpcm (short csig, short *ssindex, short *signal)
-{
- short diff, step;
- unsigned char encoded;
- unsigned char zero_count, next_flag;
- step = stpsz[*ssindex];
- /*
- * Clip csig if too large or too small
- */
-
- csig >>= 4;
-
- diff = csig - *signal;
-
- if (diff < 0)
- {
- encoded = 8;
- diff = -diff;
- }
- else
- encoded = 0;
- if (diff >= step)
- {
- encoded |= 4;
- diff -= step;
- }
- step >>= 1;
- if (diff >= step)
- {
- encoded |= 2;
- diff -= step;
- }
- step >>= 1;
- if (diff >= step)
- encoded |= 1;
-
- decode (encoded, ssindex, signal, &zero_count, &next_flag);
-
- return (encoded);
-}
-
static struct ast_filestream *vox_open(int fd)
{
/* We don't have any header to read or anything really, but
@@ -263,31 +125,19 @@
static struct ast_frame *vox_read(struct ast_filestream *s, int *whennext)
{
int res;
- int x;
/* Send a frame from the file to the appropriate channel */
s->fr.frametype = AST_FRAME_VOICE;
s->fr.subclass = AST_FORMAT_ADPCM;
s->fr.offset = AST_FRIENDLY_OFFSET;
s->fr.mallocd = 0;
s->fr.data = s->buf;
- if ((res = read(s->fd, s->buf + BUF_SHIFT, BUF_SIZE)) < 1) {
+ if ((res = read(s->fd, s->buf, BUF_SIZE)) < 1) {
if (res)
ast_log(LOG_WARNING, "Short read (%d) (%s)!\n", res, strerror(errno));
return NULL;
}
- /* Store index, then signal */
- s->buf[0] = s->ssindex & 0xff;
- s->buf[1] = (s->signal >> 8) & 0xff;
- s->buf[2] = s->signal & 0xff;
- s->buf[3] = s->zero_count;
- s->buf[4] = s->next_flag;
- /* Do the decoder to be sure we get the right stuff in the signal and index fields. */
- for (x=BUF_SHIFT;x<res+BUF_SHIFT;x++) {
- decode (s->buf[x] >> 4, &s->ssindex, &s->signal, &s->zero_count, &s->next_flag);
- decode (s->buf[x] & 0xf, &s->ssindex, &s->signal, &s->zero_count, &s->next_flag);
- }
s->fr.samples = res * 2;
- s->fr.datalen = res + BUF_SHIFT;
+ s->fr.datalen = res;
*whennext = s->fr.samples;
return &s->fr;
}
@@ -303,11 +153,7 @@
ast_log(LOG_WARNING, "Asked to write non-ADPCM frame (%d)!\n", f->subclass);
return -1;
}
- if (f->datalen < BUF_SHIFT) {
- ast_log(LOG_WARNING, "Invalid frame of data (< %d bytes long) from %s\n", BUF_SHIFT, f->src);
- return -1;
- }
- if ((res = write(fs->fd, f->data + BUF_SHIFT, f->datalen - BUF_SHIFT)) != f->datalen - BUF_SHIFT) {
+ if ((res = write(fs->fd, f->data, f->datalen)) != f->datalen) {
ast_log(LOG_WARNING, "Bad write (%d/%d): %s\n", res, f->datalen, strerror(errno));
return -1;
}
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