Make jpeg quality configurable.

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## HEAD
 
+### Enhancements
+
+- You can now set screen JPEG quality with the `SCREEN_JPEG_QUALITY` environment variable at launch time. Can be useful for slow networks.
+
 ### Fixes
 
 - Fixed Lenovo A806 and most likely other cheap Lenovo devices as well by updating [adbkit](https://github.com/openstf/adbkit).

lib/cli.js

@@ -64,6 +64,10 @@ program
     , 'screen WebSocket URL pattern'
     , String
     , 'ws://${publicIp}:${publicPort}')
+  .option('--screen-jpeg-quality <quality>'
+    , 'screen JPEG quality'
+    , Number
+    , process.env.SCREEN_JPEG_QUALITY || 80)
   .option('--connect-url-pattern <pattern>'
     , 'adb connect URL pattern'
     , String
@@ -113,6 +117,7 @@ program
         , '--adb-host', options.adbHost
         , '--adb-port', options.adbPort
         , '--screen-ws-url-pattern', options.screenWsUrlPattern
+        , '--screen-jpeg-quality', options.screenJpegQuality
         , '--connect-url-pattern', options.connectUrlPattern
         , '--heartbeat-interval', options.heartbeatInterval
         , '--vnc-initial-size', options.vncInitialSize.join('x')
@@ -182,6 +187,10 @@ program
     , 'screen WebSocket URL pattern'
     , String
     , 'ws://${publicIp}:${publicPort}')
+  .option('--screen-jpeg-quality <quality>'
+    , 'screen JPEG quality'
+    , Number
+    , process.env.SCREEN_JPEG_QUALITY || 80)
   .option('--heartbeat-interval <ms>'
     , 'heartbeat interval'
     , Number
@@ -228,6 +237,7 @@ program
     , adbHost: options.adbHost
     , adbPort: options.adbPort
     , screenWsUrlPattern: options.screenWsUrlPattern
+    , screenJpegQuality: options.screenJpegQuality
     , screenPort: options.screenPort
     , connectUrlPattern: options.connectUrlPattern
     , connectPort: options.connectPort

lib/units/device/plugins/screen/stream.js

@@ -228,7 +228,11 @@ module.exports = syrup.serial()
 
     FrameProducer.prototype._startService = function() {
       log.info('Launching screen service')
-      return minicap.run(util.format('-S -P %s', this.frameConfig.toString()))
+      return minicap.run(util.format(
+          '-S -Q %d -P %s'
+        , options.screenJpegQuality
+        , this.frameConfig.toString()
+        ))
         .timeout(10000)
     }
 

package.json

@@ -59,7 +59,7 @@
     "lodash": "^4.14.2",
     "markdown-serve": "^0.3.2",
     "mime": "^1.3.4",
-    "minicap-prebuilt": "^1.2.0",
+    "minicap-prebuilt": "^1.3.0",
     "minimatch": "^3.0.3",
     "my-local-ip": "^1.0.0",
     "openid": "^2.0.1",