examples/tutorials: The get-XXX-tags signals on playbin can return a None taglist

This commit is contained in:
Sebastian Dröge 2021-11-21 18:38:39 +02:00
parent 1ffcea4da7
commit 27613a8901
3 changed files with 50 additions and 40 deletions

View file

@ -75,18 +75,20 @@ fn example_main() {
// application is via properties, signals or action signals (or custom messages, events, queries).
// So what the following code does, is essentially asking playbin to tell us its already
// internally stored tag list for this stream index.
let tags = playbin.emit_by_name::<gst::TagList>("get-audio-tags", &[&idx]);
let tags = playbin.emit_by_name::<Option<gst::TagList>>("get-audio-tags", &[&idx]);
if let Some(artist) = tags.get::<gst::tags::Artist>() {
println!(" Artist: {}", artist.get());
}
if let Some(tags) = tags {
if let Some(artist) = tags.get::<gst::tags::Artist>() {
println!(" Artist: {}", artist.get());
}
if let Some(title) = tags.get::<gst::tags::Title>() {
println!(" Title: {}", title.get());
}
if let Some(title) = tags.get::<gst::tags::Title>() {
println!(" Title: {}", title.get());
}
if let Some(album) = tags.get::<gst::tags::Album>() {
println!(" Album: {}", album.get());
if let Some(album) = tags.get::<gst::tags::Album>() {
println!(" Album: {}", album.get());
}
}
None

View file

@ -42,24 +42,26 @@ mod tutorial5 {
let x = playbin.property::<i32>(propname);
for i in 0..x {
let tags = playbin.emit_by_name::<gst::TagList>(signame, &[&i]);
let tags = playbin.emit_by_name::<Option<gst::TagList>>(signame, &[&i]);
textbuf.insert_at_cursor(&format!("{} stream {}:\n ", stype, i));
if let Some(tags) = tags {
textbuf.insert_at_cursor(&format!("{} stream {}:\n ", stype, i));
if let Some(codec) = tags.get::<gst::tags::VideoCodec>() {
textbuf.insert_at_cursor(&format!(" codec: {} \n", codec.get()));
}
if let Some(codec) = tags.get::<gst::tags::VideoCodec>() {
textbuf.insert_at_cursor(&format!(" codec: {} \n", codec.get()));
}
if let Some(codec) = tags.get::<gst::tags::AudioCodec>() {
textbuf.insert_at_cursor(&format!(" codec: {} \n", codec.get()));
}
if let Some(codec) = tags.get::<gst::tags::AudioCodec>() {
textbuf.insert_at_cursor(&format!(" codec: {} \n", codec.get()));
}
if let Some(lang) = tags.get::<gst::tags::LanguageCode>() {
textbuf.insert_at_cursor(&format!(" language: {} \n", lang.get()));
}
if let Some(lang) = tags.get::<gst::tags::LanguageCode>() {
textbuf.insert_at_cursor(&format!(" language: {} \n", lang.get()));
}
if let Some(bitrate) = tags.get::<gst::tags::Bitrate>() {
textbuf.insert_at_cursor(&format!(" bitrate: {} \n", bitrate.get()));
if let Some(bitrate) = tags.get::<gst::tags::Bitrate>() {
textbuf.insert_at_cursor(&format!(" bitrate: {} \n", bitrate.get()));
}
}
}
}

View file

@ -21,35 +21,41 @@ fn analyze_streams(playbin: &gst::Element) {
);
for i in 0..n_video {
let tags = playbin.emit_by_name::<gst::TagList>("get-video-tags", &[&i]);
let tags = playbin.emit_by_name::<Option<gst::TagList>>("get-video-tags", &[&i]);
println!("video stream {}:", i);
if let Some(codec) = tags.get::<gst::tags::VideoCodec>() {
println!(" codec: {}", codec.get());
if let Some(tags) = tags {
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::<gst::TagList>("get-audio-tags", &[&i]);
let tags = playbin.emit_by_name::<Option<gst::TagList>>("get-audio-tags", &[&i]);
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());
if let Some(tags) = tags {
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::<gst::TagList>("get-text-tags", &[&i]);
let tags = playbin.emit_by_name::<Option<gst::TagList>>("get-text-tags", &[&i]);
println!("subtitle stream {}:", i);
if let Some(codec) = tags.get::<gst::tags::LanguageCode>() {
println!(" language: {}", codec.get());
if let Some(tags) = tags {
println!("subtitle stream {}:", i);
if let Some(codec) = tags.get::<gst::tags::LanguageCode>() {
println!(" language: {}", codec.get());
}
}
}