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-rw-r--r--addons/mp3/interface.c323
1 files changed, 323 insertions, 0 deletions
diff --git a/addons/mp3/interface.c b/addons/mp3/interface.c
new file mode 100644
index 000000000..9ced53342
--- /dev/null
+++ b/addons/mp3/interface.c
@@ -0,0 +1,323 @@
+#include <asterisk.h>
+#include <asterisk/logger.h>
+
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "mpg123.h"
+#include "mpglib.h"
+
+
+void InitMP3Constants(void)
+{
+ init_layer3_const();
+ make_decode_tables_const();
+
+}
+
+
+BOOL InitMP3(struct mpstr *mp, long outscale)
+{
+ /* quiet 4096 med 8192 */
+
+ memset(mp,0,sizeof(struct mpstr));
+
+ mp->framesize = 0;
+ mp->fsizeold = -1;
+ mp->bsize = 0;
+ mp->head = mp->tail = NULL;
+ mp->fr.single = 3; /* force mono */
+ mp->bsnum = 0;
+ mp->synth_bo = 1;
+ mp->outsamplerate = 8000;
+
+ make_decode_tables_scale(mp, outscale);
+
+ init_layer3_sample_limits(mp, SBLIMIT);
+
+ return !0;
+}
+
+void ExitMP3(struct mpstr *mp)
+{
+ struct buf *b,*bn;
+
+ b = mp->tail;
+ while(b) {
+ free(b->pnt);
+ bn = b->next;
+ free(b);
+ b = bn;
+ }
+}
+
+static struct buf *addbuf(struct mpstr *mp,char *buf,int size)
+{
+ struct buf *nbuf;
+
+ nbuf = malloc( sizeof(struct buf) );
+ if(!nbuf) {
+ ast_log(LOG_WARNING,"Out of memory!\n");
+ return NULL;
+ }
+ nbuf->pnt = malloc(size);
+ if(!nbuf->pnt) {
+ free(nbuf);
+ return NULL;
+ }
+ nbuf->size = size;
+ memcpy(nbuf->pnt,buf,size);
+ nbuf->next = NULL;
+ nbuf->prev = mp->head;
+ nbuf->pos = 0;
+
+ if(!mp->tail) {
+ mp->tail = nbuf;
+ }
+ else {
+ mp->head->next = nbuf;
+ }
+
+ mp->head = nbuf;
+ mp->bsize += size;
+
+ return nbuf;
+}
+
+static void remove_buf(struct mpstr *mp)
+{
+ struct buf *buf = mp->tail;
+
+ mp->tail = buf->next;
+ if(mp->tail)
+ mp->tail->prev = NULL;
+ else {
+ mp->tail = mp->head = NULL;
+ }
+
+ free(buf->pnt);
+ free(buf);
+
+}
+
+static int read_buf_byte(int *error, struct mpstr *mp)
+{
+ unsigned int b;int pos;
+
+ pos = mp->tail->pos;
+ while(pos >= mp->tail->size) {
+ remove_buf(mp);
+ pos = mp->tail->pos;
+ if(!mp->tail) {
+ /* We may pick up this error a few times*/
+ /* But things have gone pear shaped */
+ ast_log(LOG_WARNING,"Fatal Buffer error!\n");
+ *error = 1;
+ return (0);
+ }
+ }
+
+ b = mp->tail->pnt[pos];
+ mp->bsize--;
+ mp->tail->pos++;
+
+
+ return b;
+}
+
+static int read_head(struct mpstr *mp)
+{
+ unsigned long head;
+ int error=0;
+
+
+ head = read_buf_byte(&error, mp);
+ head <<= 8;
+ head |= read_buf_byte(&error, mp);
+ head <<= 8;
+ head |= read_buf_byte(&error, mp);
+ head <<= 8;
+ head |= read_buf_byte(&error, mp);
+
+ mp->header = head;
+
+ if(error){
+ return (1);
+ }else
+ return (0);
+
+}
+
+static int head_check(unsigned long head)
+{
+ if( (head & 0xffe00000) != 0xffe00000)
+ return FALSE;
+ if(!((head>>17)&3))
+ return FALSE;
+ if( ((head>>12)&0xf) == 0xf || ((head>>12)&0xf) == 0)
+ return FALSE;
+ if( ((head>>10)&0x3) == 0x3 )
+ return FALSE;
+ if ((head & 0xffff0000) == 0xfffe0000)
+ return FALSE;
+
+ return TRUE;
+}
+
+static int head_shift(struct mpstr *mp)
+{
+ unsigned long head;
+ int error = 0;
+
+ head = mp->header;
+
+ head <<= 8;
+ head |= read_buf_byte(&error, mp);
+
+ mp->header = head;
+
+ if (error){
+ return (1);
+ }else
+ return (0);
+
+}
+
+
+int decodeMP3(struct mpstr *mp,char *in,int isize,char *out,
+ int osize,int *done)
+{
+ int len;
+ long n,m;
+ int down_sample_sblimit;
+
+ if(osize < 4608) {
+ ast_log(LOG_WARNING,"To less out space\n");
+ return MP3_ERR;
+ }
+
+ if(in) {
+ if(addbuf(mp,in,isize) == NULL) {
+ return MP3_ERR;
+ }
+ }
+
+ /* First decode header */
+ if(mp->framesize == 0) {
+ if(mp->bsize < 4) {
+ return MP3_NEED_MORE;
+ }
+ if (read_head(mp))
+ return MP3_ERR;
+
+ if(!head_check(mp->header) ) {
+ int i;
+
+ ast_log(LOG_WARNING,"Junk at the beginning of frame %08lx\n",mp->header);
+
+ /* step in byte steps through next 64K */
+ for(i=0;i<65536;i++) {
+ if(!mp->bsize)
+ return MP3_NEED_MORE;
+
+ if(head_shift(mp))
+ return MP3_ERR;
+
+ if(head_check(mp->header))
+ break;
+ }
+ if(i == 65536) {
+ ast_log(LOG_WARNING,"Giving up searching valid MPEG header\n");
+ return MP3_ERR;
+ }
+ }
+
+ decode_header(&mp->fr,mp->header);
+ mp->framesize = mp->fr.framesize;
+
+ if (!mp->initmp3){
+ mp->initmp3 = 1;
+
+ n = freqs[mp->fr.sampling_frequency];
+ if (mp->outsamplerate) {
+ m = mp->outsamplerate;
+ }
+ else {
+ m =n;
+ }
+
+ if (synth_ntom_set_step(n,m))
+ return MP3_ERR;
+
+
+ if(n>m) {
+ down_sample_sblimit = SBLIMIT * m;
+ down_sample_sblimit /= n;
+ }
+ else {
+ down_sample_sblimit = SBLIMIT;
+ }
+
+ init_layer3_sample_limits(mp, down_sample_sblimit);
+
+ }
+ }
+
+
+ if(mp->fr.framesize > mp->bsize)
+ return MP3_NEED_MORE;
+
+ (mp->worksample).wordpointer = mp->bsspace[mp->bsnum] + 512;
+ mp->bsnum = (mp->bsnum + 1) & 0x1;
+ (mp->worksample).bitindex = 0;
+
+ len = 0;
+ while(len < mp->framesize) {
+ int nlen;
+ int blen = mp->tail->size - mp->tail->pos;
+ if( (mp->framesize - len) <= blen) {
+ nlen = mp->framesize-len;
+ }
+ else {
+ nlen = blen;
+ }
+ memcpy((mp->worksample).wordpointer+len,mp->tail->pnt+mp->tail->pos,nlen);
+ len += nlen;
+ mp->tail->pos += nlen;
+ mp->bsize -= nlen;
+ if(mp->tail->pos == mp->tail->size) {
+ remove_buf(mp);
+ }
+ }
+
+ *done = 0;
+ if(mp->fr.error_protection)
+ getbits(mp, 16);
+
+ if (do_layer3(mp,(unsigned char *) out,done))
+ return MP3_ERR;
+
+ mp->fsizeold = mp->framesize;
+ mp->framesize = 0;
+
+ return MP3_OK;
+}
+
+int set_pointer(struct mpstr *mp, long backstep)
+{
+ unsigned char *bsbufold;
+ if(mp->fsizeold < 0 && backstep > 0) {
+ ast_log(LOG_WARNING,"Can't step back %ld!\n",backstep);
+ return MP3_ERR;
+ }
+ bsbufold = mp->bsspace[mp->bsnum] + 512;
+ (mp->worksample).wordpointer -= backstep;
+ if (backstep)
+ memcpy((mp->worksample).wordpointer,bsbufold+mp->fsizeold-backstep,backstep);
+ (mp->worksample).bitindex = 0;
+ return MP3_OK;
+}
+
+
+
+
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-02 07:32:50 +0000