Testing Opencore decoder

Once compiled, the test executable is in the folder /test/amrnb-dec
the program input is amr file and the output is wav file.

./amrnb-dec outamr8khz.amr outamr8khz.wav

Looking at the code, after decoding the stream, it needs to be converted to little endian for
wav format.

while (1) {
uint8_t buffer[500], littleendian[320], *ptr;
int size, i;
int16_t outbuffer[160];
/* Read the mode byte */
n = fread(buffer, 1, 1, in);
if (n <= 0)
break;
/* Find the packet size */
size = sizes[(buffer[0] >> 3) & 0x0f];
n = fread(buffer + 1, 1, size, in);
if (n != size)
break;

/* Decode the packet */
Decoder_Interface_Decode(amr, buffer, outbuffer, 0);

/* Convert to little endian and write to wav */
ptr = littleendian;
for (i = 0; i < 160; i++) {
*ptr++ = (outbuffer[i] >> 0) & 0xff;
*ptr++ = (outbuffer[i] >> 8) & 0xff;
}
wav_write_data(wav, littleendian, 320);
}