avconv: use default channel layouts when they are unknown

If either input or output layout is known and the channel counts match,
use the known layout for both. Otherwise choose the default layout based on
av_get_default_channel_layout().

Changed some FATE references due to some WAVE files now having a non-zero
channel mask.

avconv.c

@@ -2145,6 +2145,51 @@ static void print_sdp(OutputFile *output_files, int n)
     av_freep(&avc);
 }
 
+static void get_default_channel_layouts(OutputStream *ost, InputStream *ist)
+{
+    char layout_name[256];
+    AVCodecContext *enc = ost->st->codec;
+    AVCodecContext *dec = ist->st->codec;
+
+    if (!dec->channel_layout) {
+        if (enc->channel_layout && dec->channels == enc->channels) {
+            dec->channel_layout = enc->channel_layout;
+        } else {
+            dec->channel_layout = av_get_default_channel_layout(dec->channels);
+
+            if (!dec->channel_layout) {
+                av_log(NULL, AV_LOG_FATAL, "Unable to find default channel "
+                       "layout for Input Stream #%d.%d\n", ist->file_index,
+                       ist->st->index);
+                exit_program(1);
+            }
+        }
+        av_get_channel_layout_string(layout_name, sizeof(layout_name),
+                                     dec->channels, dec->channel_layout);
+        av_log(NULL, AV_LOG_WARNING, "Guessed Channel Layout for  Input Stream "
+               "#%d.%d : %s\n", ist->file_index, ist->st->index, layout_name);
+    }
+    if (!enc->channel_layout) {
+        if (dec->channels == enc->channels) {
+            enc->channel_layout = dec->channel_layout;
+            return;
+        } else {
+            enc->channel_layout = av_get_default_channel_layout(enc->channels);
+        }
+        if (!enc->channel_layout) {
+            av_log(NULL, AV_LOG_FATAL, "Unable to find default channel layout "
+                   "for Output Stream #%d.%d\n", ost->file_index,
+                   ost->st->index);
+            exit_program(1);
+        }
+        av_get_channel_layout_string(layout_name, sizeof(layout_name),
+                                     enc->channels, enc->channel_layout);
+        av_log(NULL, AV_LOG_WARNING, "Guessed Channel Layout for Output Stream "
+               "#%d.%d : %s\n", ost->file_index, ost->st->index, layout_name);
+    }
+}
+
+
 static int init_input_stream(int ist_index, OutputStream *output_streams, int nb_output_streams,
                              char *error, int error_len)
 {
@@ -2183,6 +2228,17 @@ static int init_input_stream(int ist_index, OutputStream *output_streams, int nb
         }
         assert_codec_experimental(ist->st->codec, 0);
         assert_avoptions(ist->opts);
+
+        if (ist->st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
+            for (i = 0; i < nb_output_streams; i++) {
+                OutputStream *ost = &output_streams[i];
+                if (ost->source_index == ist_index) {
+                    if (!ist->st->codec->channel_layout || !ost->st->codec->channel_layout)
+                        get_default_channel_layouts(ost, ist);
+                    break;
+                }
+            }
+        }
     }
 
     ist->last_dts = ist->st->avg_frame_rate.num ? - ist->st->codec->has_b_frames * AV_TIME_BASE / av_q2d(ist->st->avg_frame_rate) : 0;

tests/ref/acodec/pcm_f32le

-46f44f86a18984a832206ab9e29a79f2 *./tests/data/acodec/pcm_f32le.wav
+653d82a64b7bd96ac193e105e9f92d4c *./tests/data/acodec/pcm_f32le.wav
 2116880 ./tests/data/acodec/pcm_f32le.wav
 64151e4bcc2b717aa5a8454d424d6a1f *./tests/data/pcm_f32le.acodec.out.wav
 stddev:    0.00 PSNR:999.99 MAXDIFF:    0 bytes:  1058400/  1058400

tests/ref/acodec/pcm_f64le

-ba17c6d1a270e1333e981f239bf7eb45 *./tests/data/acodec/pcm_f64le.wav
+48b4cd378f47a50dc902aa03cc8280ed *./tests/data/acodec/pcm_f64le.wav
 4233680 ./tests/data/acodec/pcm_f64le.wav
 64151e4bcc2b717aa5a8454d424d6a1f *./tests/data/pcm_f64le.acodec.out.wav
 stddev:    0.00 PSNR:999.99 MAXDIFF:    0 bytes:  1058400/  1058400

tests/ref/acodec/pcm_s24daud

 8168a5c1343553ef027541830f2cb879 *./tests/data/acodec/pcm_s24daud.302
 10368730 ./tests/data/acodec/pcm_s24daud.302
-f552afadfdfcd6348a07095da6382de5 *./tests/data/pcm_s24daud.acodec.out.wav
+7ce988d6c5b2bf0ebf0216ba15bc5cee *./tests/data/pcm_s24daud.acodec.out.wav
 stddev: 9416.28 PSNR: 16.85 MAXDIFF:42744 bytes:  6911796/  1058400

tests/ref/acodec/pcm_s24le

-a85380fb79b0d4fff38e24ac1e34bb94 *./tests/data/acodec/pcm_s24le.wav
+18ea73985dbdf59e23f5aba66145e6fe *./tests/data/acodec/pcm_s24le.wav
 1587668 ./tests/data/acodec/pcm_s24le.wav
 64151e4bcc2b717aa5a8454d424d6a1f *./tests/data/pcm_s24le.acodec.out.wav
 stddev:    0.00 PSNR:999.99 MAXDIFF:    0 bytes:  1058400/  1058400

tests/ref/acodec/pcm_s32le

-da6ed80f4f40f0082577dea80827e014 *./tests/data/acodec/pcm_s32le.wav
+8d8849fa5c5d91b9cb74f5c74e937faf *./tests/data/acodec/pcm_s32le.wav
 2116868 ./tests/data/acodec/pcm_s32le.wav
 64151e4bcc2b717aa5a8454d424d6a1f *./tests/data/pcm_s32le.acodec.out.wav
 stddev:    0.00 PSNR:999.99 MAXDIFF:    0 bytes:  1058400/  1058400