eden-emu/opus
19
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Code for handling multiple frames per packet

Browse source 
Barely tested
This commit is contained in:
Jean-Marc Valin 2011-03-13 20:41:52 -04:00
parent 0fe4078b30
commit a7d31b7b15
2 changed files with 118 additions and 16 deletions
Download patch file Download diff file Expand all files Collapse all files

132
src/opus_decoder.c
View file

@ -100,7 +100,7 @@ static int opus_packet_get_mode(const unsigned char *data)
return mode;
}
int opus_decode(OpusDecoder *st, const unsigned char *data,
static int opus_decode_frame(OpusDecoder *st, const unsigned char *data,
int len, short *pcm, int frame_size, int decode_fec)
{
int i, silk_ret=0, celt_ret=0;
@ -120,25 +120,15 @@ int opus_decode(OpusDecoder *st, const unsigned char *data,
int c;
/* Payloads of 1 (2 including ToC) or 0 trigger the PLC/DTX */
if (len<=2)
if (len<=1)
data = NULL;
audiosize = st->frame_size;
if (data != NULL)
{
mode =opus_packet_get_mode(data);
st->bandwidth = opus_packet_get_bandwidth(data);
audiosize = opus_packet_get_samples_per_frame(data, st->Fs);
st->stream_channels = opus_packet_get_nb_channels(data);
if (opus_packet_get_nb_frames(data, len)>1)
{
/* FIXME: Handle the case of multiple frames */
}
len -= 1;
data += 1;
mode = st->mode;
ec_dec_init(&dec,(unsigned char*)data,len);
} else {
audiosize = frame_size;
mode = st->prev_mode;
}
@ -154,7 +144,7 @@ int opus_decode(OpusDecoder *st, const unsigned char *data,
{
transition = 1;
if (mode == MODE_CELT_ONLY)
opus_decode(st, NULL, 0, pcm_transition, IMAX(st->Fs/100, audiosize), 0);
opus_decode_frame(st, NULL, 0, pcm_transition, IMAX(st->Fs/100, audiosize), 0);
}
if (audiosize > frame_size)
{
@ -256,7 +246,7 @@ int opus_decode(OpusDecoder *st, const unsigned char *data,
transition = 0;
if (transition && mode != MODE_CELT_ONLY)
opus_decode(st, NULL, 0, pcm_transition, IMAX(st->Fs/100, audiosize), 0);
opus_decode_frame(st, NULL, 0, pcm_transition, IMAX(st->Fs/100, audiosize), 0);
/* 5 ms redundant frame for CELT->SILK*/
if (redundancy && celt_to_silk)
@ -325,6 +315,116 @@ int opus_decode(OpusDecoder *st, const unsigned char *data,
}
int parse_size(const unsigned char *data, int len, short *size)
{
if (len<1)
{
*size = -1;
return -1;
} else if (data[0]<252)
{
*size = data[0];
return 1;
} else if (len<2)
{
*size = -1;
return -1;
} else {
*size = 4*data[1] + data[0];
return 2;
}
}
int opus_decode(OpusDecoder *st, const unsigned char *data,
int len, short *pcm, int frame_size, int decode_fec)
{
int i, bytes, nb_samples;
int count;
/* 48 x 2.5 ms = 120 ms */
short size[48];
if (len<1)
return CELT_BAD_ARG;
count = opus_packet_get_nb_frames(data, len);
st->mode = opus_packet_get_mode(data);
st->bandwidth = opus_packet_get_bandwidth(data);
st->frame_size = opus_packet_get_samples_per_frame(data, st->Fs);
st->stream_channels = opus_packet_get_nb_channels(data);
data++;
len--;
switch (data[-1]&0x3)
{
/* One frame */
case 0:
count=1;
size[0] = len;
break;
/* Two CBR frames */
case 1:
count=2;
if (len&0x1)
return OPUS_CORRUPTED_DATA;
size[0] = size[1] = len/2;
break;
/* Two VBR frames */
case 2:
count = 2;
bytes = parse_size(data, len, size);
len -= bytes;
if (size[0]<0 || size[0] > len)
return OPUS_CORRUPTED_DATA;
data += bytes;
size[1] = len-size[0];
break;
/* Multiple CBR/VBR frames (from 0 to 120 ms) */
case 3:
if (len<1)
return OPUS_CORRUPTED_DATA;
/* Number of frames encoded in bits 0 to 5 */
count = data[0]&0x3F;
data++;
len--;
/* Bit 7 is VBR flag (bit 6 is ignored) */
if (data[0]&0x80)
{
/* VBR case */
int last_size=len;
for (i=0;i<count-1;i++)
{
bytes = parse_size(data, len, size+i);
len -= bytes;
if (size[i]<0 || size[i] > len)
return OPUS_CORRUPTED_DATA;
data += bytes;
last_size -= bytes+size[i];
}
if (last_size<0)
return OPUS_CORRUPTED_DATA;
if (count)
size[count-1]=last_size;
} else {
/* CBR case */
int sz = count != 0 ? len/count : 0;
if (sz*count!=len)
return OPUS_CORRUPTED_DATA;
for (i=0;i<count;i++)
size[i] = sz;
}
break;
}
/* FIXME: Check if the number of samples fits in the output buffer */
nb_samples=0;
for (i=0;i<count;i++)
{
int ret;
ret = opus_decode_frame(st, data, len, pcm, frame_size-nb_samples, decode_fec);
if (ret<0)
return ret;
data += size[i];
pcm += ret;
nb_samples += ret;
}
return nb_samples;
}
int opus_decoder_ctl(OpusDecoder *st, int request, ...)
{
va_list ap;

2
src/opus_decoder.h
View file

@ -40,7 +40,9 @@ struct OpusDecoder {
int bandwidth;
/* Sampling rate (at the API level) */
int Fs;
int mode;
int prev_mode;
int frame_size;
int prev_redundancy;
#ifdef OPUS_TEST_RANGE_CODER_STATE