af_lavcac3enc, encode: support planar formats

This fixes operation with current ffmpeg releases.

Note that this planarization is slow and should be reverted once proper
planar audio support is there in mpv.

1 files changed, 35 insertions, 1 deletions

diff --git a/audio/reorder_ch.c b/audio/reorder_ch.c
index 4b51a79439..330a807eae 100644
--- a/audio/reorder_ch.c
+++ b/audio/reorder_ch.c
@@ -1368,7 +1368,6 @@ void reorder_channel_nch(void *buf,
                         samples, samplesize);
 }
 
-
 #ifdef TEST
 
 static void test_copy(int channels) {
@@ -1398,3 +1397,38 @@ int main(int argc, char *argv[]) {
 }
 
 #endif
+
+static inline void reorder_to_planar_(void *restrict out, const void *restrict in,
+        size_t size, size_t nchan, size_t nmemb) {
+    size_t i, c;
+    char *outptr = (char *) out;
+    size_t instep = nchan * size;
+
+    for (c = 0; c < nchan; ++c) {
+        const char *inptr = ((const char *) in) + c * size;
+        for (i = 0; i < nmemb; ++i, inptr += instep, outptr += size) {
+            memcpy(outptr, inptr, size);
+        }
+    }
+}
+
+void reorder_to_planar(void *restrict out, const void *restrict in,
+        size_t size, size_t nchan, size_t nmemb)
+{
+    // special case for mono (nothing to do...)
+    if (nchan == 1)
+        memcpy(out, in, size * nchan * nmemb);
+    // these calls exist to insert an inline copy of to_planar_ here with known
+    // value of size to help the compiler replace the memcpy calls by mov
+    // instructions
+    else if (size == 1)
+        reorder_to_planar_(out, in, 1, nchan, nmemb);
+    else if (size == 2)
+        reorder_to_planar_(out, in, 2, nchan, nmemb);
+    else if (size == 4)
+        reorder_to_planar_(out, in, 4, nchan, nmemb);
+    // general case (calls memcpy a lot, should actually never happen, but
+    // stays here for correctness purposes)
+    else
+        reorder_to_planar_(out, in, size, nchan, nmemb);
+}