@@ -26,6 +26,7 @@

 #include "libavutil/log.h"

 #include "libavutil/fifo.h"

+#include "libavutil/opt.h"

 #include "libavcodec/avcodec.h"

 #include "libavformat/avformat.h"

 #include "libavformat/timefilter.h"

@@ -36,6 +37,7 @@

 #define FIFO_PACKETS_NUM 16

 typedef struct {

+    AVClass        *class;

     jack_client_t * client;

     int             activated;

     sem_t           packet_count;

@@ -136,7 +138,7 @@ static int supply_new_packets(JackData *self, AVFormatContext *context)

     return 0;

 }

-static int start_jack(AVFormatContext *context, AVFormatParameters *params)

+static int start_jack(AVFormatContext *context)

 {

     JackData *self = context->priv_data;

     jack_status_t status;

@@ -153,7 +155,6 @@ static int start_jack(AVFormatContext *context, AVFormatParameters *params)

     sem_init(&self->packet_count, 0, 0);

     self->sample_rate = jack_get_sample_rate(self->client);

-    self->nports      = params->channels;

     self->ports       = av_malloc(self->nports * sizeof(*self->ports));

     self->buffer_size = jack_get_buffer_size(self->client);

@@ -225,10 +226,7 @@ static int audio_read_header(AVFormatContext *context, AVFormatParameters *param

     AVStream *stream;

     int test;

-    if (params->sample_rate <= 0 || params->channels <= 0)

-        return -1;

-

-    if ((test = start_jack(context, params)))

+    if ((test = start_jack(context)))

         return test;

     stream = av_new_stream(context, 0);

@@ -314,6 +312,19 @@ static int audio_read_close(AVFormatContext *context)

     return 0;

 }

+#define OFFSET(x) offsetof(JackData, x)

+static const AVOption options[] = {

+    { "channels", "Number of audio channels.", OFFSET(nports), FF_OPT_TYPE_INT, { 2 }, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },

+    { NULL },

+};

+

+static const AVClass jack_indev_class = {

+    .class_name     = "JACK indev",

+    .item_name      = av_default_item_name,

+    .option         = options,

+    .version        = LIBAVUTIL_VERSION_INT,

+};

+

 AVInputFormat ff_jack_demuxer = {

     "jack",

     NULL_IF_CONFIG_SMALL("JACK Audio Connection Kit"),

@@ -323,4 +334,5 @@ AVInputFormat ff_jack_demuxer = {

     audio_read_packet,

     audio_read_close,

     .flags = AVFMT_NOFILE,

+    .priv_class = &jack_indev_class,

 };