mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer-rs.git
synced 2024-11-22 01:21:05 +00:00
examples: Add Direct2D/DirectWrite text rendering example
Similar to overlay-composition example but for Direct2D/DirectWrite Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer-rs/-/merge_requests/1206>
This commit is contained in:
Seungha Yang
Sebastian Dröge
parent
85e427345e
commit
6cb19c1f18
2 changed files with 364 additions and 1 deletions
|
|
@ -47,7 +47,7 @@ windows = { version = "0.48", features=["Win32_Graphics_Direct3D11",
|
|||
"Win32_Foundation", "Win32_Graphics_Direct3D", "Win32_Graphics_Dxgi",
|
||||
"Win32_Graphics_Dxgi_Common", "Win32_Graphics_Direct2D",
|
||||
"Win32_Graphics_Direct2D_Common", "Win32_Graphics_DirectWrite",
|
||||
"Foundation_Numerics"], optional = true }
|
||||
"Win32_Graphics_Imaging", "Win32_System_Com", "Foundation_Numerics"], optional = true }
|
||||
|
||||
[target.'cfg(target_os = "macos")'.dependencies]
|
||||
cocoa = "0.24"
|
||||
|
|
@ -173,6 +173,10 @@ required-features = ["pango-cairo"]
|
|||
name = "overlay-composition"
|
||||
required-features = ["overlay-composition"]
|
||||
|
||||
[[bin]]
|
||||
name = "overlay-composition-d2d"
|
||||
required-features = ["windows"]
|
||||
|
||||
[[bin]]
|
||||
name = "ges"
|
||||
required-features = ["ges"]
|
||||
|
|
|
|||
359
examples/src/bin/overlay-composition-d2d.rs
Normal file
359
examples/src/bin/overlay-composition-d2d.rs
Normal file
|
|
@ -0,0 +1,359 @@
|
|||
// This example demonstrates how to draw an overlay on a video stream using
|
||||
// Direct2D/DirectWrite/WIC and the overlay composition element.
|
||||
|
||||
// {videotestsrc} - {overlaycomposition} - {capsfilter} - {videoconvert} - {autovideosink}
|
||||
// The capsfilter element allows us to dictate the video resolution we want for the
|
||||
// videotestsrc and the overlaycomposition element.
|
||||
|
||||
use std::sync::{Arc, Mutex};
|
||||
|
||||
use byte_slice_cast::*;
|
||||
|
||||
use anyhow::Error;
|
||||
use derive_more::{Display, Error};
|
||||
use gst::prelude::*;
|
||||
use windows::{
|
||||
Foundation::Numerics::*,
|
||||
Win32::{
|
||||
Graphics::{
|
||||
Direct2D::{Common::*, *},
|
||||
DirectWrite::*,
|
||||
Dxgi::Common::*,
|
||||
Imaging::*,
|
||||
},
|
||||
System::Com::*,
|
||||
},
|
||||
};
|
||||
|
||||
#[derive(Debug, Display, Error)]
|
||||
#[display(fmt = "Received error from {}: {} (debug: {:?})", src, error, debug)]
|
||||
struct ErrorMessage {
|
||||
src: glib::GString,
|
||||
error: glib::Error,
|
||||
debug: Option<glib::GString>,
|
||||
}
|
||||
|
||||
struct DrawingContext {
|
||||
// Factory for creating render target
|
||||
d2d_factory: ID2D1Factory,
|
||||
|
||||
// Used to create WIC bitmap surface
|
||||
wic_factory: IWICImagingFactory,
|
||||
|
||||
// text layout holding text information (string, font, size, etc)
|
||||
text_layout: IDWriteTextLayout,
|
||||
|
||||
// Holding rendred image
|
||||
bitmap: Option<IWICBitmap>,
|
||||
|
||||
// Bound to bitmap and used to actual Direct2D rendering
|
||||
render_target: Option<ID2D1RenderTarget>,
|
||||
|
||||
info: Option<gst_video::VideoInfo>,
|
||||
}
|
||||
|
||||
// Required for IWICBitmap
|
||||
unsafe impl Send for DrawingContext {}
|
||||
|
||||
fn create_pipeline() -> Result<gst::Pipeline, Error> {
|
||||
gst::init()?;
|
||||
|
||||
let pipeline = gst::Pipeline::default();
|
||||
|
||||
// The videotestsrc supports multiple test patterns. In this example, we will use the
|
||||
// pattern with a white ball moving around the video's center point.
|
||||
let src = gst::ElementFactory::make("videotestsrc")
|
||||
.property_from_str("pattern", "ball")
|
||||
.build()?;
|
||||
|
||||
let overlay = gst::ElementFactory::make("overlaycomposition").build()?;
|
||||
|
||||
let caps = gst_video::VideoCapsBuilder::new()
|
||||
.width(800)
|
||||
.height(800)
|
||||
.framerate((30, 1).into())
|
||||
.build();
|
||||
let capsfilter = gst::ElementFactory::make("capsfilter")
|
||||
.property("caps", &caps)
|
||||
.build()?;
|
||||
|
||||
let videoconvert = gst::ElementFactory::make("videoconvert").build()?;
|
||||
let sink = gst::ElementFactory::make("autovideosink").build()?;
|
||||
|
||||
pipeline.add_many(&[&src, &overlay, &capsfilter, &videoconvert, &sink])?;
|
||||
gst::Element::link_many(&[&src, &overlay, &capsfilter, &videoconvert, &sink])?;
|
||||
|
||||
// Most Direct2D/DirectWrite APIs (including factory methods) are marked as
|
||||
// "unsafe", but they shouldn't fail in practice
|
||||
let drawer = unsafe {
|
||||
let d2d_factory =
|
||||
D2D1CreateFactory::<ID2D1Factory>(D2D1_FACTORY_TYPE_MULTI_THREADED, None).unwrap();
|
||||
let dwrite_factory =
|
||||
DWriteCreateFactory::<IDWriteFactory>(DWRITE_FACTORY_TYPE_SHARED).unwrap();
|
||||
let text_format = dwrite_factory
|
||||
.CreateTextFormat(
|
||||
windows::w!("Arial"),
|
||||
None,
|
||||
DWRITE_FONT_WEIGHT_BOLD,
|
||||
DWRITE_FONT_STYLE_NORMAL,
|
||||
DWRITE_FONT_STRETCH_NORMAL,
|
||||
32f32,
|
||||
windows::w!("en-us"),
|
||||
)
|
||||
.unwrap();
|
||||
let text_layout = dwrite_factory
|
||||
.CreateTextLayout(
|
||||
windows::w!("GStreamer").as_wide(),
|
||||
&text_format,
|
||||
// Size will be updated later on "caps-changed" signal
|
||||
800f32,
|
||||
800f32,
|
||||
)
|
||||
.unwrap();
|
||||
|
||||
// Top (default) and center alignment
|
||||
text_layout
|
||||
.SetTextAlignment(DWRITE_TEXT_ALIGNMENT_CENTER)
|
||||
.unwrap();
|
||||
|
||||
let wic_factory: IWICImagingFactory =
|
||||
CoCreateInstance(&CLSID_WICImagingFactory, None, CLSCTX_ALL).unwrap();
|
||||
|
||||
Arc::new(Mutex::new(DrawingContext {
|
||||
d2d_factory,
|
||||
wic_factory,
|
||||
text_layout,
|
||||
bitmap: None,
|
||||
render_target: None,
|
||||
info: None,
|
||||
}))
|
||||
};
|
||||
|
||||
overlay.connect_closure(
|
||||
"draw",
|
||||
false,
|
||||
glib::closure!(@strong drawer => move |_overlay: &gst::Element,
|
||||
sample: &gst::Sample| {
|
||||
use std::f64::consts::PI;
|
||||
|
||||
let drawer = drawer.lock().unwrap();
|
||||
|
||||
let buffer = sample.buffer().unwrap();
|
||||
let timestamp = buffer.pts().unwrap();
|
||||
|
||||
let info = drawer.info.as_ref().unwrap();
|
||||
let text_layout = &drawer.text_layout;
|
||||
let bitmap = drawer.bitmap.as_ref().unwrap();
|
||||
let render_target = drawer.render_target.as_ref().unwrap();
|
||||
|
||||
let global_angle = 360. * (timestamp % (10 * gst::ClockTime::SECOND)).nseconds() as f64
|
||||
/ (10.0 * gst::ClockTime::SECOND.nseconds() as f64);
|
||||
let center_x = (info.width() / 2) as f32;
|
||||
let center_y = (info.height() / 2) as f32;
|
||||
let top_margin = (info.height() / 20) as f32;
|
||||
|
||||
unsafe {
|
||||
// Begin drawing
|
||||
render_target.BeginDraw();
|
||||
|
||||
// Clear background
|
||||
render_target.Clear(Some(&D2D1_COLOR_F {
|
||||
r: 0f32,
|
||||
g: 0f32,
|
||||
b: 0f32,
|
||||
a: 0f32,
|
||||
}));
|
||||
|
||||
// This loop will render 10 times the string "GStreamer" in a circle
|
||||
for i in 0..10 {
|
||||
let angle = (360. * f64::from(i)) / 10.0;
|
||||
let red = ((1.0 + f64::cos((angle - 60.0) * PI / 180.0)) / 2.0) as f32;
|
||||
let text_brush = render_target
|
||||
.CreateSolidColorBrush(
|
||||
&D2D1_COLOR_F {
|
||||
r: red,
|
||||
g: 0f32,
|
||||
b: 1f32 - red,
|
||||
a: 1f32,
|
||||
},
|
||||
None,
|
||||
)
|
||||
.unwrap();
|
||||
|
||||
let angle = (angle + global_angle) as f32;
|
||||
let matrix = Matrix3x2::rotation(angle, center_x, center_y);
|
||||
render_target.SetTransform(&matrix);
|
||||
render_target.DrawTextLayout(
|
||||
D2D_POINT_2F { x: 0f32, y: top_margin },
|
||||
text_layout,
|
||||
&text_brush,
|
||||
D2D1_DRAW_TEXT_OPTIONS_NONE,
|
||||
);
|
||||
}
|
||||
|
||||
// EndDraw may not be successful for some reasons.
|
||||
// Ignores any error in this example
|
||||
let _ = render_target.EndDraw(None, None);
|
||||
|
||||
// Make sure all operations is completed before copying
|
||||
// bitmap to buffer
|
||||
let _ = render_target.Flush(None::<*mut u64>, None::<*mut u64>);
|
||||
}
|
||||
|
||||
let mut buffer = gst::Buffer::with_size((info.width() * info.height() * 4) as usize).unwrap();
|
||||
{
|
||||
let buffer_mut = buffer.get_mut().unwrap();
|
||||
let mut map = buffer_mut.map_writable().unwrap();
|
||||
let dst = map.as_mut_slice_of::<u8>().unwrap();
|
||||
|
||||
unsafe {
|
||||
// Bitmap size is equal to the background image size.
|
||||
// Copy entire memory
|
||||
bitmap.CopyPixels(std::ptr::null(), info.width() * 4, dst).unwrap();
|
||||
}
|
||||
}
|
||||
|
||||
gst_video::VideoMeta::add_full(
|
||||
buffer.get_mut().unwrap(),
|
||||
gst_video::VideoFrameFlags::empty(),
|
||||
gst_video::VideoFormat::Bgra,
|
||||
info.width(),
|
||||
info.height(),
|
||||
&[0],
|
||||
&[(info.width() * 4) as i32],
|
||||
)
|
||||
.unwrap();
|
||||
|
||||
// Turn the buffer into a VideoOverlayRectangle, then place
|
||||
// that into a VideoOverlayComposition and return it.
|
||||
//
|
||||
// A VideoOverlayComposition can take a Vec of such rectangles
|
||||
// spaced around the video frame, but we're just outputting 1
|
||||
// here
|
||||
let rect = gst_video::VideoOverlayRectangle::new_raw(
|
||||
&buffer,
|
||||
0,
|
||||
0,
|
||||
info.width(),
|
||||
info.height(),
|
||||
gst_video::VideoOverlayFormatFlags::PREMULTIPLIED_ALPHA,
|
||||
);
|
||||
|
||||
gst_video::VideoOverlayComposition::new(Some(&rect))
|
||||
.unwrap()
|
||||
}),
|
||||
);
|
||||
|
||||
// Add a signal handler to the overlay's "caps-changed" signal. This could e.g.
|
||||
// be called when the sink that we render to does not support resizing the image
|
||||
// itself - but the user just changed the window-size. The element after the overlay
|
||||
// will then change its caps and we use the notification about this change to
|
||||
// resize our canvas's size.
|
||||
// Another possibility for when this might happen is, when our video is a network
|
||||
// stream that dynamically changes resolution when enough bandwith is available.
|
||||
overlay.connect_closure(
|
||||
"caps-changed",
|
||||
false,
|
||||
glib::closure!(move |_overlay: &gst::Element,
|
||||
caps: &gst::Caps,
|
||||
_width: u32,
|
||||
_height: u32| {
|
||||
let mut drawer = drawer.lock().unwrap();
|
||||
let info = gst_video::VideoInfo::from_caps(caps).unwrap();
|
||||
|
||||
unsafe {
|
||||
// Update text layout to be identical to new video resolution
|
||||
drawer.text_layout.SetMaxWidth(info.width() as f32).unwrap();
|
||||
drawer
|
||||
.text_layout
|
||||
.SetMaxHeight(info.height() as f32)
|
||||
.unwrap();
|
||||
|
||||
// Create new WIC bitmap with PBGRA format (pre-multiplied BGRA)
|
||||
let bitmap = drawer
|
||||
.wic_factory
|
||||
.CreateBitmap(
|
||||
info.width(),
|
||||
info.height(),
|
||||
&GUID_WICPixelFormat32bppPBGRA,
|
||||
WICBitmapCacheOnDemand,
|
||||
)
|
||||
.unwrap();
|
||||
|
||||
let render_target = drawer
|
||||
.d2d_factory
|
||||
.CreateWicBitmapRenderTarget(
|
||||
&bitmap,
|
||||
&D2D1_RENDER_TARGET_PROPERTIES {
|
||||
r#type: D2D1_RENDER_TARGET_TYPE_DEFAULT,
|
||||
pixelFormat: D2D1_PIXEL_FORMAT {
|
||||
format: DXGI_FORMAT_B8G8R8A8_UNORM,
|
||||
alphaMode: D2D1_ALPHA_MODE_PREMULTIPLIED,
|
||||
},
|
||||
// zero means default DPI
|
||||
dpiX: 0f32,
|
||||
dpiY: 0f32,
|
||||
usage: D2D1_RENDER_TARGET_USAGE_NONE,
|
||||
minLevel: D2D1_FEATURE_LEVEL_DEFAULT,
|
||||
},
|
||||
)
|
||||
.unwrap();
|
||||
|
||||
drawer.render_target = Some(render_target);
|
||||
drawer.bitmap = Some(bitmap);
|
||||
}
|
||||
drawer.info = Some(info);
|
||||
}),
|
||||
);
|
||||
|
||||
Ok(pipeline)
|
||||
}
|
||||
|
||||
fn main_loop(pipeline: gst::Pipeline) -> Result<(), Error> {
|
||||
pipeline.set_state(gst::State::Playing)?;
|
||||
|
||||
let bus = pipeline
|
||||
.bus()
|
||||
.expect("Pipeline without bus. Shouldn't happen!");
|
||||
|
||||
for msg in bus.iter_timed(gst::ClockTime::NONE) {
|
||||
use gst::MessageView;
|
||||
|
||||
match msg.view() {
|
||||
MessageView::Eos(..) => break,
|
||||
MessageView::Error(err) => {
|
||||
pipeline.set_state(gst::State::Null)?;
|
||||
return Err(ErrorMessage {
|
||||
src: msg
|
||||
.src()
|
||||
.map(|s| s.path_string())
|
||||
.unwrap_or_else(|| glib::GString::from("UNKNOWN")),
|
||||
error: err.error(),
|
||||
debug: err.debug(),
|
||||
}
|
||||
.into());
|
||||
}
|
||||
_ => (),
|
||||
}
|
||||
}
|
||||
|
||||
pipeline.set_state(gst::State::Null)?;
|
||||
|
||||
Ok(())
|
||||
}
|
||||
|
||||
fn main() {
|
||||
// WIC requires COM initialization
|
||||
unsafe {
|
||||
CoInitializeEx(None, COINIT_MULTITHREADED).unwrap();
|
||||
}
|
||||
|
||||
match create_pipeline().and_then(main_loop) {
|
||||
Ok(r) => r,
|
||||
Err(e) => eprintln!("Error! {}", e),
|
||||
}
|
||||
|
||||
unsafe {
|
||||
CoUninitialize();
|
||||
}
|
||||
}
|
||||
Loading…
Reference in a new issue