| |
| /*! |
| ************************************************************************ |
| * \file nalu.c |
| * |
| * \brief |
| * Common NALU support functions |
| * |
| * \author |
| * Main contributors (see contributors.h for copyright, address and affiliation details) |
| * - Stephan Wenger <stewe@cs.tu-berlin.de> |
| ************************************************************************ |
| */ |
| |
| #include <assert.h> |
| #include <memory.h> |
| |
| #include "global.h" |
| #include "nalu.h" |
| |
| /*! |
| ************************************************************************************* |
| * \brief |
| * Converts an RBSP to a NALU |
| * |
| * \param rbsp |
| * byte buffer with the rbsp |
| * \param nalu |
| * nalu structure to be filled |
| * \param rbsp_size |
| * size of the rbsp in bytes |
| * \param nal_unit_type |
| * as in JVT doc |
| * \param nal_reference_idc |
| * as in JVT doc |
| * \param min_num_bytes |
| * some incomprehensible CABAC stuff |
| * \param UseAnnexbLongStartcode |
| * when 1 and when using AnnexB bytestreams, then use a long startcode prefix |
| * |
| * \return |
| * length of the NALU in bytes |
| ************************************************************************************* |
| */ |
| |
| int RBSPtoNALU (unsigned char *rbsp, NALU_t *nalu, int rbsp_size, int nal_unit_type, int nal_reference_idc, |
| int min_num_bytes, int UseAnnexbLongStartcode) |
| { |
| int len; |
| |
| assert (nalu != NULL); |
| assert (nal_reference_idc <=3 && nal_reference_idc >=0); |
| assert (nal_unit_type > 0 && nal_unit_type <= 10); |
| assert (rbsp_size < MAXRBSPSIZE); |
| |
| nalu->forbidden_bit = 0; |
| nalu->nal_reference_idc = nal_reference_idc; |
| nalu->nal_unit_type = nal_unit_type; |
| nalu->startcodeprefix_len = UseAnnexbLongStartcode?4:3; |
| nalu->buf[0] = |
| nalu->forbidden_bit << 7 | |
| nalu->nal_reference_idc << 5 | |
| nalu->nal_unit_type; |
| |
| memcpy (&nalu->buf[1], rbsp, rbsp_size); |
| // printf ("First Byte %x\n", nalu->buf[0]); |
| // printf ("RBSPtoNALU: Before: NALU len %d\t RBSP %x %x %x %x\n", rbsp_size, (unsigned) nalu->buf[1], (unsigned) nalu->buf[2], (unsigned) nalu->buf[3], (unsigned) nalu->buf[4]); |
| |
| len = 1 + RBSPtoEBSP (&nalu->buf[1], 0, rbsp_size, min_num_bytes); |
| |
| // printf ("RBSPtoNALU: After : NALU len %d\t EBSP %x %x %x %x\n", rbsp_size, (unsigned) nalu->buf[1], (unsigned) nalu->buf[2], (unsigned) nalu->buf[3], (unsigned) nalu->buf[4]); |
| // printf ("len %d\n\n", len); |
| nalu->len = len; |
| |
| return len; |
| } |
| |
| |
