diff options
Diffstat (limited to 'src/pcm_utils.c')
| -rw-r--r-- | src/pcm_utils.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/src/pcm_utils.c b/src/pcm_utils.c index 52f9294b7..cb6f93f63 100644 --- a/src/pcm_utils.c +++ b/src/pcm_utils.c @@ -385,6 +385,29 @@ pcm_convert_channels_2_to_1(int16_t *dest, const int16_t *src, } } +static void +pcm_convert_channels_n_to_2(int16_t *dest, + unsigned src_channels, const int16_t *src, + unsigned num_frames) +{ + unsigned c; + + assert(src_channels > 0); + + while (num_frames-- > 0) { + int32_t sum = 0; + int16_t value; + + for (c = 0; c < src_channels; ++c) + sum += *src++; + value = sum / (int)src_channels; + + /* XXX this is actually only mono ... */ + *dest++ = value; + *dest++ = value; + } +} + static const int16_t * pcm_convertChannels(int8_t dest_channels, int8_t src_channels, const int16_t *src, @@ -406,6 +429,9 @@ pcm_convertChannels(int8_t dest_channels, pcm_convert_channels_1_to_2(buf, src, num_frames); else if (src_channels == 2 && dest_channels == 1) pcm_convert_channels_2_to_1(buf, src, num_frames); + else if (dest_channels == 2) + pcm_convert_channels_n_to_2(buf, src_channels, src, + num_frames); else { ERROR("conversion %u->%u channels is not supported\n", src_channels, dest_channels); |