[Libav-user] Not able to resample with libavfilter

[Paul B Mahol]

On 6/19/17, amey jain <amey.jain7 at gmail.com> wrote:
> Hi,
> I want resampled output of 5512 Hz, mono channel, in float. I am using
> aformat filter with these parameters and buffersrc sink. All things
> are working fine except for the output frames collected from sink.
> When I get sample_rate using frame->sample_rate, I get 48000 as
> output. Also the value to nb_samples remains same. Can someone guide
> me out here. Below is code I am using.
>
> //buffer src aformat initialized
>
> resample = avfilter_get_by_name("aformat");
> resample_ctx = avfilter_graph_alloc_filter(filter_graph, resample,
> "aformat");
> av_get_channel_layout_string(ch_layout, sizeof(ch_layout),
> 0,AV_CH_LAYOUT_MONO);
> av_opt_set(resample_ctx, "channel_layout", ch_layout,
> AV_OPT_SEARCH_CHILDREN);
> av_opt_set(resample_ctx,
> "sample_fmt",av_get_sample_fmt_name(AV_SAMPLE_FMT_FLT),
> AV_OPT_SEARCH_CHILDREN);
> av_opt_set_q(resample_ctx, "time_base", (AVRational){ 1, 5512
> },AV_OPT_SEARCH_CHILDREN);
> av_opt_set_int(resample_ctx, "sample_rate", 5512, AV_OPT_SEARCH_CHILDREN);
> avfilter_init_str(resample_ctx, NULL);
>
> //buffer sink abuffersink initialized and all three linked together

Mandatory code is missing. We can not guess it, please provide it or
ask for help
somewhere else.