forked from mirrors/gstreamer-rs
79 lines
2.2 KiB
Rust
79 lines
2.2 KiB
Rust
extern crate gstreamer as gst;
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use gst::prelude::*;
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extern crate gstreamer_audio as gst_audio;
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extern crate byte_slice_cast;
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use byte_slice_cast::*;
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use std::u64;
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use std::i16;
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fn main() {
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gst::init().unwrap();
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let pipeline = gst::parse_launch(&format!(
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"audiotestsrc name=src ! audio/x-raw,format={},channels=1 ! fakesink",
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gst_audio::AUDIO_FORMAT_S16.to_string()
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)).unwrap();
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let bus = pipeline.get_bus().unwrap();
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let src = pipeline
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.clone()
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.dynamic_cast::<gst::Bin>()
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.unwrap()
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.get_by_name("src")
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.unwrap();
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let src_pad = src.get_static_pad("src").unwrap();
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src_pad.add_probe(gst::PAD_PROBE_TYPE_BUFFER, |_, probe_info| {
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if let Some(gst::PadProbeData::Buffer(ref buffer)) = probe_info.data {
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let map = buffer.map_readable().unwrap();
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let samples = if let Ok(samples) = map.as_slice().as_slice_of::<i16>() {
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samples
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} else {
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return gst::PadProbeReturn::Ok;
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};
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let sum: f64 = samples
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.iter()
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.map(|sample| {
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let f = (*sample as f64) / (i16::MAX as f64);
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f * f
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})
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.sum();
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let rms = (sum / (samples.len() as f64)).sqrt();
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println!("rms: {}", rms);
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}
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gst::PadProbeReturn::Ok
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});
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let ret = pipeline.set_state(gst::State::Playing);
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assert_ne!(ret, gst::StateChangeReturn::Failure);
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loop {
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use gst::MessageView;
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let msg = match bus.timed_pop(u64::MAX) {
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None => break,
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Some(msg) => msg,
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};
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match msg.view() {
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MessageView::Eos(..) => break,
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MessageView::Error(err) => {
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println!(
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"Error from {}: {} ({:?})",
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msg.get_src().get_path_string(),
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err.get_error(),
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err.get_debug()
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);
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break;
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}
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_ => (),
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}
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}
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let ret = pipeline.set_state(gst::State::Null);
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assert_ne!(ret, gst::StateChangeReturn::Failure);
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}
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