Add resolution bitrate thresholds to EncoderInfo.

When provided, these thresholds will be used instead of WebRTC default
limits specified in DropDueToSize() and GetMaxDefaultVideoBitrateKbps().

Bug: none
Change-Id: Ida45ea832041963b8b8475d69114b5c60a172fb7
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/142170
Commit-Queue: Sergey Silkin <ssilkin@webrtc.org>
Reviewed-by: Erik Språng <sprang@webrtc.org>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Reviewed-by: Alex Glaznev <glaznev@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#28390}

sdk/android/api/org/webrtc/VideoEncoder.java

@@ -11,6 +11,8 @@
 package org.webrtc;
 
 import android.support.annotation.Nullable;
+import java.util.Collections;
+import java.util.List;
 import org.webrtc.EncodedImage;
 
 /**
@@ -181,6 +183,59 @@ public interface VideoEncoder {
     }
   }
 
+  /**
+   * Bitrate thresholds for resolution.
+   */
+  public class ResolutionBitrateThresholds {
+    /**
+     * Maximum size of video frame, in pixels, the bitrate thresholds are intended for.
+     */
+    public final int frameSizePixels;
+
+    /**
+     * Recommended minimum bitrate to start encoding.
+     */
+    public final int minStartBitrateBps;
+
+    /**
+     * Recommended minimum bitrate.
+     */
+    public final int minBitrateBps;
+
+    /**
+     * Recommended maximum bitrate.
+     */
+    public final int maxBitrateBps;
+
+    public ResolutionBitrateThresholds(
+        int frameSizePixels, int minStartBitrateBps, int minBitrateBps, int maxBitrateBps) {
+      this.frameSizePixels = frameSizePixels;
+      this.minStartBitrateBps = minStartBitrateBps;
+      this.minBitrateBps = minBitrateBps;
+      this.maxBitrateBps = maxBitrateBps;
+    }
+
+    @CalledByNative("ResolutionBitrateThresholds")
+    public int getFrameSizePixels() {
+      return frameSizePixels;
+    }
+
+    @CalledByNative("ResolutionBitrateThresholds")
+    public int getMinStartBitrateBps() {
+      return minStartBitrateBps;
+    }
+
+    @CalledByNative("ResolutionBitrateThresholds")
+    public int getMinBitrateBps() {
+      return minBitrateBps;
+    }
+
+    @CalledByNative("ResolutionBitrateThresholds")
+    public int getMaxBitrateBps() {
+      return maxBitrateBps;
+    }
+  }
+
   public interface Callback {
     /**
      * Call to return an encoded frame. It is safe to assume the byte buffer held by |frame| is not
@@ -240,6 +295,14 @@ public interface VideoEncoder {
   /** Any encoder that wants to use WebRTC provided quality scaler must implement this method. */
   @CalledByNative ScalingSettings getScalingSettings();
 
+  /** Returns the list of resolution bitrate thresholds. */
+  @CalledByNative
+  default ResolutionBitrateThresholds[] getResolutionBitrateThresholds() {
+    // TODO(ssilkin): Update downstream projects and remove default implementation.
+    ResolutionBitrateThresholds thresholds[] = {};
+    return thresholds;
+  }
+
   /**
    * Should return a descriptive name for the implementation. Gets called once and cached. May be
    * called from arbitrary thread.