Make QualityScaler not downscale below QVGA.

webrtc/api/java/jni/androidmediaencoder_jni.cc

 /*
  *  Copyright 2015 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 334 matching lines @@
       jni, j_output_buffer_info_class, "presentationTimestampUs", "J");
   CHECK_EXCEPTION(jni) << "MediaCodecVideoEncoder ctor failed";
   srand(time(NULL));
   AllowBlockingCalls();
 }
 
 int32_t MediaCodecVideoEncoder::InitEncode(
     const webrtc::VideoCodec* codec_settings,
     int32_t /* number_of_cores */,
     size_t /* max_payload_size */) {
-  const int kMinDimension = 180;
   if (codec_settings == NULL) {
     ALOGE << "NULL VideoCodec instance";
     return WEBRTC_VIDEO_CODEC_ERR_PARAMETER;
   }
   // Factory should guard against other codecs being used with us.
   RTC_CHECK(codec_settings->codecType == codecType_)
       << "Unsupported codec " << codec_settings->codecType << " for "
       << codecType_;
 
   codec_mode_ = codec_settings->mode;
@@ skipping 24 matching lines @@
       quality_scaler_.Init(kLowQpThreshold, kBadQpThreshold, false,
                            codec_settings->startBitrate, codec_settings->width,
                            codec_settings->height,
                            codec_settings->maxFramerate);
     } else {
       // When adding codec support to additional hardware codecs, also configure
       // their QP thresholds for scaling.
       RTC_NOTREACHED() << "Unsupported codec without configured QP thresholds.";
       scale_ = false;
     }
-    quality_scaler_.SetMinResolution(kMinDimension, kMinDimension);
     QualityScaler::Resolution res = quality_scaler_.GetScaledResolution();
-    init_width = std::max(res.width, kMinDimension);
-    init_height = std::max(res.height, kMinDimension);
+    init_width = res.width;
+    init_height = res.height;
     ALOGD << "Scaled resolution: " << init_width << " x " << init_height;
   }
 
   return codec_thread_->Invoke<int32_t>(
       Bind(&MediaCodecVideoEncoder::InitEncodeOnCodecThread,
            this,
            init_width,
            init_height,
            codec_settings->startBitrate,
            codec_settings->maxFramerate,
@@ skipping 219 matching lines @@
     ALOGW << "Encoder drop frame - failed callback.";
     drop_next_input_frame_ = false;
     current_timestamp_us_ += rtc::kNumMicrosecsPerSec / last_set_fps_;
     frames_dropped_media_encoder_++;
     OnDroppedFrame();
     return WEBRTC_VIDEO_CODEC_OK;
   }
 
   RTC_CHECK(frame_types->size() == 1) << "Unexpected stream count";
 
   // Check if we accumulated too many frames in encoder input buffers and drop

[pbos-webrtc, 2016/04/13 14:00:54]

(Sorry, this is part of a rebase.)

   // frame if so.
   if (frames_in_queue_ > MAX_ENCODER_Q_SIZE) {
     ALOGD << "Already " << frames_in_queue_ << " frames in the queue, dropping"
           << ". TS: " << (int)(current_timestamp_us_ / 1000)
           << ". Fps: " << last_set_fps_
           << ". Consecutive drops: " << consecutive_full_queue_frame_drops_;
     current_timestamp_us_ += rtc::kNumMicrosecsPerSec / last_set_fps_;
     consecutive_full_queue_frame_drops_++;
     if (consecutive_full_queue_frame_drops_ >=
         ENCODER_STALL_FRAMEDROP_THRESHOLD) {
@@ skipping 599 matching lines @@
 }
 
 void MediaCodecVideoEncoderFactory::DestroyVideoEncoder(
     webrtc::VideoEncoder* encoder) {
   ALOGD << "Destroy video encoder.";
   delete encoder;
 }
 
 }  // namespace webrtc_jni