tutorials: Add playback-tutorial-1

This commit is contained in:
yatinmaan 2021-04-26 19:31:18 +05:30
parent 890cd03632
commit ffe6821813
2 changed files with 221 additions and 0 deletions

View file

@ -26,3 +26,7 @@ tutorial5-quartz = ["tutorial5"]
[[bin]]
name = "basic-tutorial-13"
required-features = ["termion"]
[[bin]]
name = "playback-tutorial-1"
required-features = ["termion"]

View file

@ -0,0 +1,217 @@
use glib::FlagsClass;
use gst::prelude::*;
use anyhow::Error;
use termion::event::Key;
use termion::input::TermRead;
use std::{thread, time};
#[path = "../tutorials-common.rs"]
mod tutorials_common;
fn analyze_streams(playbin: &gst::Element) {
let n_video = playbin.property("n-video").unwrap().get::<i32>().unwrap();
let n_audio = playbin.property("n-audio").unwrap().get::<i32>().unwrap();
let n_text = playbin.property("n-text").unwrap().get::<i32>().unwrap();
println!(
"{} video stream(s), {} audio stream(s), {} text stream(s)",
n_video, n_audio, n_text
);
for i in 0..n_video {
let tags = playbin
.emit_by_name("get-video-tags", &[&i])
.unwrap()
.unwrap();
if let Ok(tags) = tags.get::<gst::TagList>() {
println!("video stream {}:", i);
if let Some(codec) = tags.get::<gst::tags::VideoCodec>() {
println!(" codec: {}", codec.get());
}
}
}
for i in 0..n_audio {
let tags = playbin
.emit_by_name("get-audio-tags", &[&i])
.unwrap()
.unwrap();
if let Ok(tags) = tags.get::<gst::TagList>() {
println!("audio stream {}:", i);
if let Some(codec) = tags.get::<gst::tags::AudioCodec>() {
println!(" codec: {}", codec.get());
}
if let Some(codec) = tags.get::<gst::tags::LanguageCode>() {
println!(" language: {}", codec.get());
}
if let Some(codec) = tags.get::<gst::tags::Bitrate>() {
println!(" bitrate: {}", codec.get());
}
}
}
for i in 0..n_text {
let tags = playbin
.emit_by_name("get-text-tags", &[&i])
.unwrap()
.unwrap();
if let Ok(tags) = tags.get::<gst::TagList>() {
println!("subtitle stream {}:", i);
if let Some(codec) = tags.get::<gst::tags::LanguageCode>() {
println!(" language: {}", codec.get());
}
}
}
let current_video = playbin
.property("current-video")
.unwrap()
.get::<i32>()
.unwrap();
let current_audio = playbin
.property("current-audio")
.unwrap()
.get::<i32>()
.unwrap();
let current_text = playbin
.property("current-text")
.unwrap()
.get::<i32>()
.unwrap();
println!(
"Currently playing video stream {}, audio stream {}, text stream {}",
current_video, current_audio, current_text
);
println!("Type any number and hit ENTER to select a different audio stream");
}
fn handle_keyboard(playbin: &gst::Element, main_loop: &glib::MainLoop) {
let mut stdin = termion::async_stdin().keys();
loop {
if let Some(Ok(input)) = stdin.next() {
match input {
Key::Char(index) => {
if let Some(index) = index.to_digit(10) {
// Here index can only be 0-9
let index = index as i32;
let n_audio = playbin.property("n-audio").unwrap().get::<i32>().unwrap();
if index < n_audio {
println!("Setting current audio stream to {}", index);
playbin.set_property("current-audio", index).unwrap();
} else {
eprintln!("Index out of bounds");
}
}
}
Key::Ctrl('c') => {
main_loop.quit();
break;
}
_ => continue,
};
}
thread::sleep(time::Duration::from_millis(50));
}
}
fn tutorial_main() -> Result<(), Error> {
// Set up main loop
let main_loop = glib::MainLoop::new(None, false);
// Initialize GStreamer
gst::init()?;
// Create PlayBin element
let playbin = gst::ElementFactory::make("playbin", Some("playbin"))?;
// Set URI to play
let uri =
"https://www.freedesktop.org/software/gstreamer-sdk/data/media/sintel_cropped_multilingual.webm";
playbin.set_property("uri", uri)?;
// Set flags to show Audio and Video but ignore Subtitles
let flags = playbin.property("flags")?;
let flags_class = FlagsClass::new(flags.type_()).unwrap();
let flags = flags_class
.builder_with_value(flags)
.unwrap()
.set_by_nick("audio")
.set_by_nick("video")
.unset_by_nick("text")
.build()
.unwrap();
playbin.set_property_from_value("flags", &flags)?;
// Set connection speed. This will affect some internal decisions of playbin
playbin.set_property("connection-speed", 56u64)?;
// Handle keyboard input
let playbin_clone = playbin.clone();
let main_loop_clone = main_loop.clone();
thread::spawn(move || handle_keyboard(&playbin_clone, &main_loop_clone));
// Add a bus watch, so we get notified when a message arrives
let playbin_clone = playbin.clone();
let main_loop_clone = main_loop.clone();
let bus = playbin.bus().unwrap();
bus.add_watch(move |_bus, message| {
use gst::MessageView;
match message.view() {
MessageView::Error(err) => {
eprintln!(
"Error received from element {:?} {}",
err.src().map(|s| s.path_string()),
err.error()
);
eprintln!("Debugging information: {:?}", err.debug());
main_loop_clone.quit();
Continue(false)
}
MessageView::StateChanged(state_changed) => {
if state_changed
.src()
.map(|s| s == playbin_clone)
.unwrap_or(false)
&& state_changed.current() == gst::State::Playing
{
analyze_streams(&playbin_clone);
}
Continue(true)
}
MessageView::Eos(..) => {
println!("Reached end of stream");
main_loop_clone.quit();
Continue(false)
}
_ => Continue(true),
}
})?;
// Set to PLAYING
playbin.set_state(gst::State::Playing)?;
// Set GLib mainlooop to run
main_loop.run();
// Clean up
playbin.set_state(gst::State::Null)?;
Ok(())
}
fn main() {
// tutorials_common::run is only required to set up the application environment on macOS
// (but not necessary in normal Cocoa applications where this is set up automatically)
match tutorials_common::run(tutorial_main) {
Ok(_) => {}
Err(err) => eprintln!("Failed: {}", err),
};
}