fix android bit rate

Cargo.lock

@@ -4265,6 +4265,7 @@ dependencies = [
  "quest",
  "repng",
  "serde 1.0.136",
+ "serde_json 1.0.79",
  "target_build_utils",
  "tracing",
  "webm",

flutter/android/app/src/main/kotlin/com/carriez/flutter_hbb/MainService.kt

@@ -72,7 +72,13 @@ class MainService : Service() {
     @Keep
     fun rustGetByName(name: String): String {
         return when (name) {
-            "screen_size" -> "${SCREEN_INFO.width}:${SCREEN_INFO.height}"
+            "screen_size" -> {
+                JSONObject().apply {
+                    put("width",SCREEN_INFO.width)
+                    put("height",SCREEN_INFO.height)
+                    put("scale",SCREEN_INFO.scale)
+                }.toString()
+            }
             else -> ""
         }
     }

libs/scrap/Cargo.toml

@@ -28,6 +28,7 @@ android_logger = "0.10"
 jni = "0.19"
 lazy_static = "1.4"
 log = "0.4"
+serde_json = "1.0"
 
 [target.'cfg(not(target_os = "android"))'.dev-dependencies]
 repng = "0.2"

libs/scrap/src/common/android.rs

@@ -1,11 +1,13 @@
 use crate::android::ffi::*;
 use crate::rgba_to_i420;
 use lazy_static::lazy_static;
+use serde_json::Value;
+use std::collections::HashMap;
 use std::io;
 use std::sync::Mutex;
 
 lazy_static! {
-    static ref SCREEN_SIZE: Mutex<(u16, u16)> = Mutex::new((0, 0));
+    static ref SCREEN_SIZE: Mutex<(u16, u16, u16)> = Mutex::new((0, 0, 0)); // (width, height, scale)
 }
 
 pub struct Capturer {
@@ -65,9 +67,7 @@ impl Display {
     pub fn primary() -> io::Result<Display> {
         let mut size = SCREEN_SIZE.lock().unwrap();
         if size.0 == 0 || size.1 == 0 {
-            let (w, h) = get_size().unwrap_or((0, 0));
-            size.0 = w;
-            size.1 = h;
+            *size = get_size().unwrap_or_default();
         }
         Ok(Display {
             default: true,
@@ -111,19 +111,33 @@ impl Display {
 
     pub fn refresh_size() {
         let mut size = SCREEN_SIZE.lock().unwrap();
-        let (w, h) = get_size().unwrap_or((0, 0));
-        size.0 = w;
-        size.1 = h;
+        *size = get_size().unwrap_or_default();
+    }
+
+    // Big android screen size will be shrinked, to improve performance when screen-capturing and encoding
+    // e.g 2280x1080 size will be set to 1140x540, and `scale` is 2
+    // need to multiply by `4` (2*2) when compute the bitrate
+    pub fn fix_quality() -> u16 {
+        let scale = SCREEN_SIZE.lock().unwrap().2;
+        if scale <= 0 {
+            1
+        } else {
+            scale * scale
+        }
     }
 }
 
-fn get_size() -> Option<(u16, u16)> {
+fn get_size() -> Option<(u16, u16, u16)> {
     let res = call_main_service_get_by_name("screen_size").ok()?;
-    if res.len() > 0 {
-        let mut sp = res.split(":");
-        let w = sp.next()?.parse::<u16>().ok()?;
-        let h = sp.next()?.parse::<u16>().ok()?;
-        return Some((w, h));
+    if let Ok(json) = serde_json::from_str::<HashMap<String, Value>>(&res) {
+        if let (Some(Value::Number(w)), Some(Value::Number(h)), Some(Value::Number(scale))) =
+            (json.get("width"), json.get("height"), json.get("scale"))
+        {
+            let w = w.as_i64()? as _;
+            let h = h.as_i64()? as _;
+            let scale = scale.as_i64()? as _;
+            return Some((w, h, scale));
+        }
     }
     None
 }

libs/scrap/src/common/mod.rs

@@ -19,7 +19,7 @@ cfg_if! {
     } else if #[cfg(dxgi)] {
         mod dxgi;
         pub use self::dxgi::*;
-    } else if #[cfg(android)] {
+    } else if #[cfg(target_os = "android")] {
         mod android;
         pub use self::android::*;
     }else {
@@ -36,13 +36,11 @@ mod vpx;
 
 #[inline]
 pub fn would_block_if_equal(old: &mut Vec<u128>, b: &[u8]) -> std::io::Result<()> {
-    let b = unsafe {
-        std::slice::from_raw_parts::<u128>(b.as_ptr() as _, b.len() / 16)
-    };
+    let b = unsafe { std::slice::from_raw_parts::<u128>(b.as_ptr() as _, b.len() / 16) };
     if b == &old[..] {
         return Err(std::io::ErrorKind::WouldBlock.into());
     }
     old.resize(b.len(), 0);
     old.copy_from_slice(b);
     Ok(())
-}
+}

libs/scrap/src/lib.rs

@@ -14,13 +14,13 @@ pub mod quartz;
 #[cfg(x11)]
 pub mod x11;
 
-#[cfg(all(x11, feature="wayland"))]
+#[cfg(all(x11, feature = "wayland"))]
 pub mod wayland;
 
 #[cfg(dxgi)]
 pub mod dxgi;
 
-#[cfg(android)]
+#[cfg(target_os = "android")]
 pub mod android;
 
 mod common;

src/server/video_service.rs

@@ -567,5 +567,15 @@ fn get_quality(w: usize, h: usize, q: i32) -> (u32, u32, u32, i32) {
     let bitrate = q >> 8 & 0xFF;
     let quantizer = q & 0xFF;
     let b = ((w * h) / 1000) as u32;
+
+    #[cfg(target_os = "android")]
+    {
+        // fix when andorid screen shrinks
+        let fix = Display::fix_quality() as u32;
+        log::debug!("Android screen, fix quality:{}", fix);
+        let b = b * fix;
+        return (bitrate as u32 * b / 100, quantizer as _, 56, 7);
+    }
+
     (bitrate as u32 * b / 100, quantizer as _, 56, 7)
 }