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authorwm4 <wm4@nowhere>2013-05-13 00:38:35 +0200
committerwm4 <wm4@nowhere>2013-05-13 00:39:07 +0200
commit279f4b59dc08950a90379ef5905736167c79a438 (patch)
treedd00ee2e8fe1ae2476e3350574ed364c593b4da0 /audio/reorder_ch.c
parent35c8f7b6082871d690c4355d5173dde939bf60ec (diff)
downloadmpv-279f4b59dc08950a90379ef5905736167c79a438.tar.bz2
mpv-279f4b59dc08950a90379ef5905736167c79a438.tar.xz
audio: fix compilation with older libavresample versions
The libavresample version of the current Libav stable release lacks the avresample_set_channel_mapping() function. (FFmpeg's libswresample seems to be fine, because they added swr_set_channel_mapping() first.) Add a cheap/slow workaround to do channel reordering on our own. We don't use the recently removed MPlayer code (see commit 586b75a), because that is not generic enough. The functionality should be the same as with full-featured libavresample, and any differences are bugs. It's probably slower, though.
Diffstat (limited to 'audio/reorder_ch.c')
-rw-r--r--audio/reorder_ch.c53
1 files changed, 52 insertions, 1 deletions
diff --git a/audio/reorder_ch.c b/audio/reorder_ch.c
index 3a2b747668..57cb664a6f 100644
--- a/audio/reorder_ch.c
+++ b/audio/reorder_ch.c
@@ -22,8 +22,10 @@
#include <inttypes.h>
#include <string.h>
+#include <assert.h>
-#include "audio/reorder_ch.h"
+#include "chmap.h"
+#include "reorder_ch.h"
static inline void reorder_to_planar_(void *restrict out, const void *restrict in,
size_t size, size_t nchan, size_t nmemb)
@@ -92,3 +94,52 @@ void reorder_to_packed(uint8_t *out, uint8_t **in,
else
reorder_to_packed_(out, in, size, nchan, nmemb);
}
+
+#define MAX_SAMPLESIZE 8
+
+static void reorder_channels_(uint8_t *restrict data, int *restrict ch_order,
+ size_t sample_size, size_t num_ch,
+ size_t num_frames)
+{
+ char buffer[MP_NUM_CHANNELS * MAX_SAMPLESIZE];
+ for (size_t f = 0; f < num_frames; f++) {
+ for (uint8_t c = 0; c < num_ch; c++) {
+ memcpy(buffer + sample_size * c, data + sample_size * ch_order[c],
+ sample_size);
+ }
+ memcpy(data, buffer, sample_size * num_ch);
+ data += num_ch * sample_size;
+ }
+}
+
+// Reorders for each channel:
+// out[ch] = in[ch_order[ch]] (but in-place)
+// num_ch is the number of channels
+// sample_size is e.g. 2 for s16le
+// full byte size of in/out = num_ch * sample_size * num_frames
+// Do not use this function in new code; use libavresample instead.
+void reorder_channels(void *restrict data, int *restrict ch_order,
+ size_t sample_size, size_t num_ch, size_t num_frames)
+{
+ // Check 1:1 mapping
+ bool need_reorder = false;
+ for (int n = 0; n < num_ch; n++)
+ need_reorder |= ch_order[n] != n;
+ if (!need_reorder)
+ return;
+ assert(sample_size <= MAX_SAMPLESIZE);
+ assert(num_ch <= MP_NUM_CHANNELS);
+ // See reorder_to_planar() why this is done this way
+ // s16 and float are the most common sample sizes, and 6 channels is the
+ // most common case where reordering is required.
+ if (sample_size == 2 && num_ch == 6)
+ reorder_channels_(data, ch_order, 2, 6, num_frames);
+ else if (sample_size == 2)
+ reorder_channels_(data, ch_order, 2, num_ch, num_frames);
+ else if (sample_size == 4 && num_ch == 6)
+ reorder_channels_(data, ch_order, 4, 6, num_frames);
+ else if (sample_size == 4)
+ reorder_channels_(data, ch_order, 4, num_ch, num_frames);
+ else
+ reorder_channels_(data, ch_order, sample_size, num_ch, num_frames);
+}