libtwamr encoder: always emit frame->mode = mode; In the original implementation of amr_encode_frame(), the 'mode' member of the output struct was set to 0xFF if the output frame type is TX_NO_DATA. This design was made to mimic the mode field (16-bit word) being set to 0xFFFF (or -1) in 3GPP test sequence format - but nothing actually depends on this struct member being set in any way, and amr_frame_to_tseq() generates the needed 0xFFFF on its own, based on frame->type being equal to TX_NO_DATA. It is simpler and more efficient to always set frame->mode to the actual encoding mode in amr_encode_frame(), and this new behavior has already been documented in doc/AMR-library-API description in anticipation of the present change.

/*
 * Here we implement our PCM read helper function for "robe" format.
 */

#include <stdio.h>
#include <stdint.h>
#include "roberead.h"

int robe_get_pcm_block(FILE *inf, int16_t *pcm)
{
	uint8_t bytes[320], *dp;
	int cc, i;

	cc = fread(bytes, 1, 320, inf);
	cc >>= 1;
	dp = bytes;
	for (i = 0; i < cc; i++) {
		pcm[i] = (dp[0] << 8) | dp[1];
		dp += 2;
	}
	while (i < 160)
		pcm[i++] = 0;
	return cc;
}