fix android bit rate

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
 }