asrc_anullsrc: do not set samplerate and channel layout explicitly

They are auto-negotiated.

libavfilter/asrc_anullsrc.c

@@ -29,56 +29,6 @@
 #include "avfilter.h"
 #include "internal.h"
 
-typedef struct {
-    uint64_t channel_layout;
-    int64_t sample_rate;
-} ANullContext;
-
-static int init(AVFilterContext *ctx, const char *args)
-{
-    ANullContext *priv = ctx->priv;
-    char channel_layout_str[128] = "";
-
-    priv->sample_rate = 44100;
-    priv->channel_layout = AV_CH_LAYOUT_STEREO;
-
-    if (args)
-        sscanf(args, "%"PRId64":%s", &priv->sample_rate, channel_layout_str);
-
-    if (priv->sample_rate < 0) {
-        av_log(ctx, AV_LOG_ERROR, "Invalid negative sample rate: %"PRId64"\n", priv->sample_rate);
-        return AVERROR(EINVAL);
-    }
-
-    if (*channel_layout_str)
-        if (!(priv->channel_layout = av_get_channel_layout(channel_layout_str))
-            && sscanf(channel_layout_str, "%"PRId64, &priv->channel_layout) != 1) {
-            av_log(ctx, AV_LOG_ERROR, "Invalid value '%s' for channel layout\n",
-                   channel_layout_str);
-            return AVERROR(EINVAL);
-        }
-
-    return 0;
-}
-
-static int config_props(AVFilterLink *outlink)
-{
-    ANullContext *priv = outlink->src->priv;
-    char buf[128];
-    int chans_nb;
-
-    outlink->sample_rate = priv->sample_rate;
-    outlink->channel_layout = priv->channel_layout;
-
-    chans_nb = av_get_channel_layout_nb_channels(priv->channel_layout);
-    av_get_channel_layout_string(buf, sizeof(buf), chans_nb, priv->channel_layout);
-    av_log(outlink->src, AV_LOG_VERBOSE,
-           "sample_rate:%"PRId64 " channel_layout:%"PRId64 " channel_layout_description:'%s'\n",
-           priv->sample_rate, priv->channel_layout, buf);
-
-    return 0;
-}
-
 static int request_frame(AVFilterLink *link)
 {
     return -1;
@@ -88,7 +38,6 @@ static const AVFilterPad avfilter_asrc_anullsrc_outputs[] = {
     {
         .name          = "default",
         .type          = AVMEDIA_TYPE_AUDIO,
-        .config_props  = config_props,
         .request_frame = request_frame,
     },
     { NULL }
@@ -98,9 +47,6 @@ AVFilter avfilter_asrc_anullsrc = {
     .name        = "anullsrc",
     .description = NULL_IF_CONFIG_SMALL("Null audio source, never return audio frames."),
 
-    .init        = init,
-    .priv_size   = sizeof(ANullContext),
-
     .inputs      = NULL,
 
     .outputs     = avfilter_asrc_anullsrc_outputs,