ffplay: try multiple sample rates if audio open fails

Should fix ticket #3509.
Signed-off-by: Marton Balint <cus@passwd.hu>

ffplay.c

@@ -2415,6 +2415,8 @@ static int audio_open(void *opaque, int64_t wanted_channel_layout, int wanted_nb
     SDL_AudioSpec wanted_spec, spec;
     const char *env;
     static const int next_nb_channels[] = {0, 0, 1, 6, 2, 6, 4, 6};
+    static const int next_sample_rates[] = {0, 44100, 48000, 96000, 192000};
+    int next_sample_rate_idx = FF_ARRAY_ELEMS(next_sample_rates) - 1;
 
     env = SDL_getenv("SDL_AUDIO_CHANNELS");
     if (env) {
@@ -2425,24 +2427,32 @@ static int audio_open(void *opaque, int64_t wanted_channel_layout, int wanted_nb
         wanted_channel_layout = av_get_default_channel_layout(wanted_nb_channels);
         wanted_channel_layout &= ~AV_CH_LAYOUT_STEREO_DOWNMIX;
     }
-    wanted_spec.channels = av_get_channel_layout_nb_channels(wanted_channel_layout);
+    wanted_nb_channels = av_get_channel_layout_nb_channels(wanted_channel_layout);
+    wanted_spec.channels = wanted_nb_channels;
     wanted_spec.freq = wanted_sample_rate;
     if (wanted_spec.freq <= 0 || wanted_spec.channels <= 0) {
         av_log(NULL, AV_LOG_ERROR, "Invalid sample rate or channel count!\n");
         return -1;
     }
+    while (next_sample_rate_idx && next_sample_rates[next_sample_rate_idx] >= wanted_spec.freq)
+        next_sample_rate_idx--;
     wanted_spec.format = AUDIO_S16SYS;
     wanted_spec.silence = 0;
     wanted_spec.samples = SDL_AUDIO_BUFFER_SIZE;
     wanted_spec.callback = sdl_audio_callback;
     wanted_spec.userdata = opaque;
     while (SDL_OpenAudio(&wanted_spec, &spec) < 0) {
-        av_log(NULL, AV_LOG_WARNING, "SDL_OpenAudio (%d channels): %s\n", wanted_spec.channels, SDL_GetError());
+        av_log(NULL, AV_LOG_WARNING, "SDL_OpenAudio (%d channels, %d Hz): %s\n",
+               wanted_spec.channels, wanted_spec.freq, SDL_GetError());
         wanted_spec.channels = next_nb_channels[FFMIN(7, wanted_spec.channels)];
         if (!wanted_spec.channels) {
-            av_log(NULL, AV_LOG_ERROR,
-                   "No more channel combinations to try, audio open failed\n");
-            return -1;
+            wanted_spec.freq = next_sample_rates[next_sample_rate_idx--];
+            wanted_spec.channels = wanted_nb_channels;
+            if (!wanted_spec.freq) {
+                av_log(NULL, AV_LOG_ERROR,
+                       "No more combinations to try, audio open failed\n");
+                return -1;
+            }
         }
         wanted_channel_layout = av_get_default_channel_layout(wanted_spec.channels);
     }