Refactor: bitstream.c full cleanup

This commit is contained in:
Marko Viitanen 2013-09-18 15:45:46 +03:00
parent df8c5a6acd
commit db3d8d8a6e

View file

@ -18,7 +18,7 @@
#include <math.h>
#include <string.h>
#include <stdarg.h>
/* for hton */
//for hton
#ifdef WIN32
#include <Winsock2.h>
#else
@ -54,38 +54,43 @@ int floor_log2(unsigned int n) {
return ((n == 0) ? (-1) : pos);
}
//Initialize the Exp Golomb code table with desired number of values
/**
* \brief Initialize the Exp Golomb code table with desired number of values
* \param len table length to init
*
* Allocates g_exp_table with len*sizeof(bit_table) and fills it with exponential golomb codes
*/
void init_exp_golomb(uint32_t len)
{
uint32_t code_num;
uint32_t M;
uint32_t info;
g_exp_table=(bit_table*)malloc(len*sizeof(bit_table));
g_exp_table = (bit_table*)malloc(len*sizeof(bit_table));
for(code_num=0;code_num<len;code_num++)
{
M=(uint32_t)floor_log2(code_num+1);
info=code_num+1-(uint32_t)pow(2,M);
g_exp_table[code_num].len=M*2+1;
g_exp_table[code_num].value=(1<<M)|info;
//printf_cavlc("Len: %i %x\n", M*2+1, (1<<M)|info);
for (code_num = 0; code_num < len; code_num++) {
M = (uint32_t)floor_log2(code_num + 1);
info = code_num + 1 - (uint32_t)pow(2, M);
g_exp_table[code_num].len = M * 2 + 1;
g_exp_table[code_num].value = (1<<M) | info;
}
}
/*
* Clear bitstream
/**
* \brief Clear bitstream
*/
void bitstream_init(bitstream* stream)
void bitstream_init(bitstream *stream)
{
stream->cur_byte=0;
stream->cur_bit=0;
stream->cur_byte = 0;
stream->cur_bit = 0;
memset(stream->data, 0, sizeof(uint32_t)*32);
}
/*
* Allocate buffer
/**
* \brief Allocate buffer
* \param stream pointer bitstream to put the data
* \param alloc size to allocate
*/
void bitstream_alloc(bitstream* stream, uint32_t alloc)
void bitstream_alloc(bitstream *stream, uint32_t alloc)
{
stream->buffer = (uint8_t*)malloc(alloc);
stream->bufferlen = alloc;
@ -93,127 +98,110 @@ void bitstream_alloc(bitstream* stream, uint32_t alloc)
bitstream_clear_buffer(stream);
}
void bitstream_clear_buffer(bitstream* stream)
/**
* \brief clear output buffer
*/
void bitstream_clear_buffer(bitstream *stream)
{
memset(stream->buffer,0,stream->bufferlen);
memset(stream->buffer, 0, stream->bufferlen);
stream->buffer_pos = 0;
}
/*!
\brief Put bits to bitstream
\param stream pointer bitstream to put the data
\param data input data
\param bits number of bits to write from data to stream
*/
void bitstream_put(bitstream* stream, uint32_t data, uint8_t bits)
/**
* \brief Put bits to bitstream
* \param stream pointer bitstream to put the data
* \param data input data
* \param bits number of bits to write from data to stream
*/
void bitstream_put(bitstream *stream, uint32_t data, uint8_t bits)
{
uint32_t bitsleft=32-stream->cur_bit;
uint32_t bitsleft = 32 - stream->cur_bit;
#ifdef VERBOSE
uint8_t i=0;
printf_bitstream("put: ");
for(i=0;i<bits;i++)
{
for (i = 0; i < bits; i++) {
printf("%i",(data&(1<<(bits-i-1)))?1:0);
}
printf_bitstream("\n");
//printf_bitstream(" count: %i\n",bits);
#endif
//Theres space for all the bits
if(bits<=bitsleft)
{
//There's space for all the bits
if (bits <= bitsleft) {
stream->data[stream->cur_byte] |= (data<<((bitsleft-bits)));
stream->cur_bit+=bits;
bits=0;
}
//No space for everything, store the bits we can and continue later
else
{
stream->cur_bit += bits;
bits = 0;
} else { //No space for everything, store the bits we can and continue later
stream->data[stream->cur_byte] |= (data>>(bits-bitsleft));
stream->cur_bit=32;
bits-=bitsleft;
stream->cur_bit = 32;
bits -= bitsleft;
}
//Check if the buffer is full
if(stream->cur_bit==32)
{
bitsleft=32;
//Check if the buffer is full, and flush to output if it is
if (stream->cur_bit == 32) {
bitsleft = 32;
stream->cur_byte++;
stream->cur_bit = 0;
if(stream->cur_byte==32)
{
if (stream->cur_byte == 32) {
//Flush data out
bitstream_flush(stream);
}
}
//..still some writing to do
if(bits!=0)
{
//Write the last of the bits (if buffer was full and flushed before)
if (bits != 0) {
stream->data[stream->cur_byte] |= (data<<(bitsleft-bits));
stream->cur_bit+=bits;
stream->cur_bit += bits;
}
}
/*!
\brief Align the bitstream
*/
void bitstream_align(bitstream* stream)
{
bitstream_put(stream,1, 1);
if((stream->cur_bit&7) != 0)
{
bitstream_put(stream,0, 8-(stream->cur_bit&7));
}
}
void bitstream_align_zero(bitstream* stream)
{
if((stream->cur_bit&7) != 0)
{
bitstream_put(stream,0, 8-(stream->cur_bit&7));
}
}
void bitstream_flush(bitstream* stream)
{
/*
* SAVE DATA TO OUTPUT
/**
* \brief Align the bitstream with one-bit padding
*/
void bitstream_align(bitstream *stream)
{
bitstream_put(stream, 1, 1);
if ((stream->cur_bit & 7) != 0) {
bitstream_put(stream, 0, 8 - (stream->cur_bit & 7));
}
}
/**
* \brief Align the bitstream with zero
*/
void bitstream_align_zero(bitstream *stream)
{
if ((stream->cur_bit & 7) != 0) {
bitstream_put(stream, 0, 8 - (stream->cur_bit & 7));
}
}
/**
* \brief Flush bitstream to output
*/
void bitstream_flush(bitstream *stream)
{
int i;
uint32_t correct_endian;
if(stream->output)
{
if(stream->cur_byte)
{
fwrite(&stream->data[0], stream->cur_byte*4, 1, stream->output);
}
//If output open, write to output
if (stream->output) {
if (stream->cur_byte) fwrite(&stream->data[0], stream->cur_byte * 4, 1, stream->output);
if (stream->cur_bit>>3) fwrite(&stream->data[stream->cur_byte], stream->cur_bit>>3, 1, stream->output);
if(stream->cur_bit>>3)
{
fwrite(&stream->data[stream->cur_byte], stream->cur_bit>>3, 1, stream->output);
}
}
/* No file open, write to buffer */
else
{
if(stream->cur_byte)
{
/* Handle endianness issue */
for(i = 0; i < stream->cur_byte; i++)
{
/* "network" is big-endian */
} else { //No file open, write to buffer
if (stream->cur_byte) {
//Handle endianness issue
for (i = 0; i < stream->cur_byte; i++) {
//"network" is big-endian
correct_endian = htonl(stream->data[i]);
memcpy((uint8_t*)&stream->buffer[stream->buffer_pos],&correct_endian,4);
memcpy((uint8_t*)&stream->buffer[stream->buffer_pos], &correct_endian, 4);
stream->buffer_pos += 4;
}
}
if(stream->cur_bit>>3)
{
if (stream->cur_bit>>3) {
correct_endian = htonl(stream->data[stream->cur_byte]);
memcpy((uint8_t*)&stream->buffer[stream->buffer_pos],&correct_endian,stream->cur_bit>>3);
memcpy((uint8_t*)&stream->buffer[stream->buffer_pos], &correct_endian, stream->cur_bit>>3);
stream->buffer_pos += stream->cur_bit>>3;
}
}