/****************************************************************************
Non static functions
****************************************************************************/
int32_t get_next_nal_unit(nal_unit * nalu)
{
int32_t i, segment_start;
int32_t nalu_size = 0;
// search for the next NALU start
for (;;) {
if (input_remain <= 4)
return 0; //scan the ring BUF
if ((!ring_buf[ring_pos]) &&
(!ring_buf[(ring_pos + 1) & RING_MOD]) &&
(!ring_buf[(ring_pos + 2) & RING_MOD]) &&
(ring_buf[(ring_pos + 3) & RING_MOD] == 1))
break;
gnn_advance();
}
for (i = 0; i < 4; ++i)
gnn_advance();
// add bytes to the NALU until the end is found
segment_start = ring_pos;
while (input_remain) {
if ((!ring_buf[ring_pos]) &&
(!ring_buf[(ring_pos + 1) & RING_MOD]) &&
(!ring_buf[(ring_pos + 2) & RING_MOD]))
break;
ring_pos = (ring_pos + 1) & RING_MOD;
--input_remain;
if (ring_pos == 0) {
gnn_add_segment(RING_BUF_SIZE);
input_read(&ring_buf[HALF_RING], HALF_RING);
}
if (ring_pos == HALF_RING) {
gnn_add_segment(HALF_RING);
input_read(&ring_buf[0], HALF_RING);
}
}
gnn_add_segment(ring_pos);
if (!nalu_size)
return 0;
// read the NAL unit
nal_pos[0] = 0;
nal_bit[0] = 0;
nalu->forbidden_zero_bit = input_get_bits(1);
nalu->nal_ref_idc = input_get_bits(2);
nalu->nal_unit_type = input_get_bits(5);
nalu->last_rbsp_byte = &nal_buf[0][nalu_size - 1];
nalu->NumBytesInNALunit = nalu_size;
EBSPtoRBSP(nal_buf[0],nalu_size,0);
return 1;
}
int NALUtoRBSP (NALU_t *nalu)
{
assert (nalu != NULL);
nalu->len = EBSPtoRBSP (nalu->buf, nalu->len, 1) ;
return nalu->len ;
}
unsigned char *remove_03emu(unsigned char *from, unsigned char *to)
{
int num=to-from;
int newsize = EBSPtoRBSP (from,num,0); //TODO: Do something if newsize == -1 (broken NAL)
if (newsize==-1)
return NULL;
return from+newsize;
}
int NALUtoRBSP (NALU_t *nalu)
{
assert (nalu != NULL); //++ È·±£nalu²»Îª¿Õ
nalu->len = EBSPtoRBSP (nalu->buf, nalu->len, 1) ;
return nalu->len ;
}
AVCDec_Status BitstreamInit(AVCDecBitstream *stream, uint8 *buffer, int size)
{
EBSPtoRBSP(buffer, &size);
stream->incnt = 0;
stream->incnt_next = 0;
stream->bitcnt = 0;
stream->curr_word = stream->next_word = 0;
stream->read_pos = 0;
stream->bitstreamBuffer = buffer;
stream->data_end_pos = size;
stream->nal_size = size;
return AVCDEC_SUCCESS;
}
