Tweaks to jack input, lower latency and distinction from jack-out

Signed-off-by: falkTX <falktx@falktx.com>

libavdevice/jack.c

@@ -38,7 +38,7 @@
 /**
  * Size of the internal FIFO buffers as a number of audio packets
  */
-#define FIFO_PACKETS_NUM 16
+#define FIFO_PACKETS_NUM 4
 
 typedef struct JackData {
     AVClass        *class;
@@ -196,7 +196,7 @@ static int start_jack(AVFormatContext *context)
     self->filled_pkts = av_fifo_alloc_array(FIFO_PACKETS_NUM, sizeof(AVPacket));
     /* New packets FIFO with one extra packet for safety against underruns */
     self->new_pkts    = av_fifo_alloc_array((FIFO_PACKETS_NUM + 1), sizeof(AVPacket));
-    if (!self->new_pkts) {
+    if (!self->new_pkts || !self->filled_pkts) {
         jack_client_close(self->client);
         return AVERROR(ENOMEM);
     }
@@ -303,12 +303,12 @@ static int audio_read_packet(AVFormatContext *context, AVPacket *pkt)
     }
 
     if (self->pkt_xrun) {
-        av_log(context, AV_LOG_WARNING, "Audio packet xrun\n");
+        av_log(context, AV_LOG_WARNING, "Audio sink packet xrun\n");
         self->pkt_xrun = 0;
     }
 
     if (self->jack_xrun) {
-        av_log(context, AV_LOG_WARNING, "JACK xrun\n");
+        av_log(context, AV_LOG_WARNING, "JACK input xrun\n");
         self->jack_xrun = 0;
     }