Signed-off-by: Marton Balint <c...@passwd.hu>
---
libavutil/channel_layout.c | 40 ++++++++++++++++++++++++++------------
1 file changed, 28 insertions(+), 12 deletions(-)
diff --git a/libavutil/channel_layout.c b/libavutil/channel_layout.c
index c60ccf368f..fb2335a334 100644
--- a/libavutil/channel_layout.c
+++ b/libavutil/channel_layout.c
@@ -644,29 +644,29 @@ int av_channel_layout_copy(AVChannelLayout *dst, const
AVChannelLayout *src)
}
/**
- * If the custom layout is n-th order standard-order ambisonic, with optional
- * extra non-diegetic channels at the end, write its string description in bp.
- * Return a negative error code on error.
+ * If the layout is n-th order standard-order ambisonic, with optional
+ * extra non-diegetic channels at the end, return the order.
+ * Return a negative error code otherwise.
*/
-static int try_describe_ambisonic(AVBPrint *bp, const AVChannelLayout
*channel_layout)
+static int ambisonic_order(const AVChannelLayout *channel_layout)
{
int i, highest_ambi, order;
highest_ambi = -1;
- if (channel_layout->order == AV_CHANNEL_ORDER_AMBISONIC)
+ if (channel_layout->order == AV_CHANNEL_ORDER_AMBISONIC) {
highest_ambi = channel_layout->nb_channels -
av_popcount64(channel_layout->u.mask) - 1;
- else {
+ } else if (channel_layout->order == AV_CHANNEL_ORDER_CUSTOM) {
const AVChannelCustom *map = channel_layout->u.map;
for (i = 0; i < channel_layout->nb_channels; i++) {
int is_ambi = CHAN_IS_AMBI(map[i].id);
/* ambisonic following non-ambisonic */
if (i > 0 && is_ambi && !CHAN_IS_AMBI(map[i - 1].id))
- return 0;
+ return AVERROR(EINVAL);
/* non-default ordering */
if (is_ambi && map[i].id - AV_CHAN_AMBISONIC_BASE != i)
- return 0;
+ return AVERROR(EINVAL);
if (CHAN_IS_AMBI(map[i].id))
highest_ambi = i;
@@ -674,17 +674,33 @@ static int try_describe_ambisonic(AVBPrint *bp, const
AVChannelLayout *channel_l
}
/* no ambisonic channels*/
if (highest_ambi < 0)
- return 0;
+ return AVERROR(EINVAL);
order = floor(sqrt(highest_ambi));
/* incomplete order - some harmonics are missing */
if ((order + 1) * (order + 1) != highest_ambi + 1)
+ return AVERROR(EINVAL);
+
+ return order;
+}
+
+/**
+ * If the custom layout is n-th order standard-order ambisonic, with optional
+ * extra non-diegetic channels at the end, write its string description in bp.
+ * Return a negative error code on error.
+ */
+static int try_describe_ambisonic(AVBPrint *bp, const AVChannelLayout
*channel_layout)
+{
+ int nb_ambi_channels;
+ int order = ambisonic_order(channel_layout);
+ if (order < 0)
return 0;
av_bprintf(bp, "ambisonic %d", order);
/* extra channels present */
- if (highest_ambi < channel_layout->nb_channels - 1) {
+ nb_ambi_channels = (order + 1) * (order + 1);
+ if (nb_ambi_channels < channel_layout->nb_channels) {
AVChannelLayout extra = { 0 };
char buf[128];
@@ -696,12 +712,12 @@ static int try_describe_ambisonic(AVBPrint *bp, const
AVChannelLayout *channel_l
const AVChannelCustom *map = channel_layout->u.map;
extra.order = AV_CHANNEL_ORDER_CUSTOM;
- extra.nb_channels = channel_layout->nb_channels - highest_ambi - 1;
+ extra.nb_channels = channel_layout->nb_channels - nb_ambi_channels;
extra.u.map = av_calloc(extra.nb_channels,
sizeof(*extra.u.map));
if (!extra.u.map)
return AVERROR(ENOMEM);
- memcpy(extra.u.map, &map[highest_ambi + 1],
+ memcpy(extra.u.map, &map[nb_ambi_channels],
sizeof(*extra.u.map) * extra.nb_channels);
}
--
2.31.1
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