char array to qint24 array

[goocreations]

I'm doing music processing on 24bit samples. The raw samples are stored in a char array. I want to convert this array to a qint24 array.

Now since there is no qint24 type, I decided to use qint32. A char has a size of 1 byte, so I will have to convert 3 chars to a 24bit sample at a time and store it in a qint32. This is what I'm currently doing:

char temp[3];
int bufferCurrent;
for(int i = 0; i < size; ++i)
{
	bufferCurrent = i * 3;
	temp[0] = buffer[bufferCurrent];
	temp[1] = buffer[bufferCurrent + 1];
	temp[2] = buffer[bufferCurrent + 2];
	result[i] = reinterpret_cast<qint32>(temp);
}

buffer is the char array and result my new array for the 24bit samples. g++ complaints that it can't convert char* to qint32 (loses precision).

So I basically need some way to convert 3 chars to a qint32. Any ideas of how to accomplish this?

[teemup]

I believe you could do this (didn't test it, but should work)

int a,b,c;
for(int i = 0; i < size; i+= 3)
{	
	a = (buffer[i]);
	if (i + 1 < size)
		b =  (buffer[i+1]);
	else
		b = 0;
	if (i + 2 < size)
		c =  (buffer[i+2]);	
	else
		c = 0;
	
	result[i] = (qint32)((a << 16) | (b << 8) | c); 
}

This also takes in account situations where amount of original samples is not dividable by 3.