From: Dan Minor <dminor@mozilla.com>
Date: Thu, 21 Mar 2019 15:48:00 +0000
Subject: Bug 1535584 - Restore UpdateCodecFrameSize to vp9_impl.cc; r=bwc

Differential Revision: https://phabricator.services.mozilla.com/D23713
Mercurial Revision: https://hg.mozilla.org/mozilla-central/rev/0898f9cfe09273e1d86c38abdd576cdf273009f0
---
 .../codecs/vp9/libvpx_vp9_encoder.cc          | 50 +++++++++++++++++++
 1 file changed, 50 insertions(+)

diff --git a/modules/video_coding/codecs/vp9/libvpx_vp9_encoder.cc b/modules/video_coding/codecs/vp9/libvpx_vp9_encoder.cc
index 35b13058a2..5877373b76 100644
--- a/modules/video_coding/codecs/vp9/libvpx_vp9_encoder.cc
+++ b/modules/video_coding/codecs/vp9/libvpx_vp9_encoder.cc
@@ -1159,6 +1159,14 @@ int LibvpxVp9Encoder::Encode(const VideoFrame& input_image,
     config_changed_ = false;
   }
 
+  if (input_image.width() != codec_.width ||
+      input_image.height() != codec_.height) {
+    int ret = UpdateCodecFrameSize(input_image);
+    if (ret < 0) {
+      return ret;
+    }
+  }
+
   RTC_DCHECK_EQ(input_image.width(), raw_->d_w);
   RTC_DCHECK_EQ(input_image.height(), raw_->d_h);
 
@@ -1286,6 +1294,48 @@ int LibvpxVp9Encoder::Encode(const VideoFrame& input_image,
   return WEBRTC_VIDEO_CODEC_OK;
 }
 
+int LibvpxVp9Encoder::UpdateCodecFrameSize(
+    const VideoFrame& input_image) {
+  RTC_LOG(LS_INFO) << "Reconfiging VP from " <<
+          codec_.width << "x" << codec_.height << " to " <<
+          input_image.width() << "x" << input_image.height();
+  // Preserve latest bitrate/framerate setting
+  // TODO: Mozilla - see below, we need to save more state here.
+  //uint32_t old_bitrate_kbit = config_->rc_target_bitrate;
+  //uint32_t old_framerate = codec_.maxFramerate;
+
+  codec_.width = input_image.width();
+  codec_.height = input_image.height();
+
+  vpx_img_free(raw_);
+  raw_ = vpx_img_wrap(NULL, VPX_IMG_FMT_I420, codec_.width, codec_.height,
+                      1, NULL);
+  // Update encoder context for new frame size.
+  config_->g_w = codec_.width;
+  config_->g_h = codec_.height;
+
+  // Determine number of threads based on the image size and #cores.
+  config_->g_threads = NumberOfThreads(codec_.width, codec_.height,
+                                       num_cores_);
+
+  // NOTE: We would like to do this the same way vp8 does it
+  // (with vpx_codec_enc_config_set()), but that causes asserts
+  // in AQ 3 (cyclic); and in AQ 0 it works, but on a resize to smaller
+  // than 1/2 x 1/2 original it asserts in convolve().  Given these
+  // bugs in trying to do it the "right" way, we basically re-do
+  // the initialization.
+  vpx_codec_destroy(encoder_); // clean up old state
+  int result = InitAndSetControlSettings(&codec_);
+  if (result == WEBRTC_VIDEO_CODEC_OK) {
+    // TODO: Mozilla rates have become much more complicated, we need to store
+    // more state or find another way of doing this.
+    //return SetRates(old_bitrate_kbit, old_framerate);
+    RTC_CHECK(false);
+    return WEBRTC_VIDEO_CODEC_UNINITIALIZED;
+  }
+  return result;
+}
+
 bool LibvpxVp9Encoder::PopulateCodecSpecific(CodecSpecificInfo* codec_specific,
                                              absl::optional<int>* spatial_idx,
                                              absl::optional<int>* temporal_idx,
-- 
2.34.1