From 5981bf2eb66858eeea2072a81ac122433b10a3b7 Mon Sep 17 00:00:00 2001
From: Peter Hanspers <peterhanspers@webrtc.org>
Date: Tue, 1 Jun 2021 07:31:00 +0200
Subject: [PATCH] Add resolution alignment properties to RTCVideoEncoder
 protocol.
MIME-Version: 1.0
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With this change, RTCVideoEncoder can specify:
- requested_resolution_alignment,
- apply_alignment_to_all_simulcast_layers
in the same way scaling_settings is specified.

Change-Id: I3de79a2eabaae581d6a9f2ef3e39496b9545a4f5

Bug: webrtc:12829
Change-Id: I3de79a2eabaae581d6a9f2ef3e39496b9545a4f5
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/220933
Reviewed-by: Kári Helgason <kthelgason@webrtc.org>
Reviewed-by: Åsa Persson <asapersson@webrtc.org>
Reviewed-by: Abby Yeh <abbyyeh@webrtc.org>
Commit-Queue: Peter Hanspers <peterhanspers@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#34196}
---
 .../api/video_codec/RTCWrappedNativeVideoEncoder.mm    | 10 ++++++++++
 sdk/objc/base/RTCVideoEncoder.h                        |  7 +++++++
 sdk/objc/components/video_codec/RTCVideoEncoderH264.mm |  8 ++++++++
 sdk/objc/native/src/objc_video_encoder_factory.mm      |  2 ++
 4 files changed, 27 insertions(+)

diff --git a/sdk/objc/api/video_codec/RTCWrappedNativeVideoEncoder.mm b/sdk/objc/api/video_codec/RTCWrappedNativeVideoEncoder.mm
index 843b6ad001..ea2a459360 100644
--- a/sdk/objc/api/video_codec/RTCWrappedNativeVideoEncoder.mm
+++ b/sdk/objc/api/video_codec/RTCWrappedNativeVideoEncoder.mm
@@ -69,4 +69,14 @@
   return nil;
 }
 
+- (NSInteger)resolutionAlignment {
+  RTC_NOTREACHED();
+  return 1;
+}
+
+- (BOOL)applyAlignmentToAllSimulcastLayers {
+  RTC_NOTREACHED();
+  return NO;
+}
+
 @end
diff --git a/sdk/objc/base/RTCVideoEncoder.h b/sdk/objc/base/RTCVideoEncoder.h
index 29e8a89901..f5b24d8fa5 100644
--- a/sdk/objc/base/RTCVideoEncoder.h
+++ b/sdk/objc/base/RTCVideoEncoder.h
@@ -43,6 +43,13 @@ RTC_OBJC_EXPORT
  *  disables quality scaling. */
 - (nullable RTC_OBJC_TYPE(RTCVideoEncoderQpThresholds) *)scalingSettings;
 
+/** Resolutions should be aligned to this value. */
+@property(nonatomic, readonly) NSInteger resolutionAlignment;
+
+/** If enabled, resolution alignment is applied to all simulcast layers simultaneously so that when
+    scaled, all resolutions comply with 'resolutionAlignment'. */
+@property(nonatomic, readonly) BOOL applyAlignmentToAllSimulcastLayers;
+
 @end
 
 NS_ASSUME_NONNULL_END
diff --git a/sdk/objc/components/video_codec/RTCVideoEncoderH264.mm b/sdk/objc/components/video_codec/RTCVideoEncoderH264.mm
index e64f61912a..ae03bf8c86 100644
--- a/sdk/objc/components/video_codec/RTCVideoEncoderH264.mm
+++ b/sdk/objc/components/video_codec/RTCVideoEncoderH264.mm
@@ -529,6 +529,14 @@ NSUInteger GetMaxSampleRate(const webrtc::H264ProfileLevelId &profile_level_id)
   return WEBRTC_VIDEO_CODEC_OK;
 }
 
+- (NSInteger)resolutionAlignment {
+  return 1;
+}
+
+- (BOOL)applyAlignmentToAllSimulcastLayers {
+  return NO;
+}
+
 #pragma mark - Private
 
 - (NSInteger)releaseEncoder {
diff --git a/sdk/objc/native/src/objc_video_encoder_factory.mm b/sdk/objc/native/src/objc_video_encoder_factory.mm
index e51fc9d319..13185aa9e0 100644
--- a/sdk/objc/native/src/objc_video_encoder_factory.mm
+++ b/sdk/objc/native/src/objc_video_encoder_factory.mm
@@ -95,6 +95,8 @@ class ObjCVideoEncoder : public VideoEncoder {
     info.scaling_settings = qp_thresholds ? ScalingSettings(qp_thresholds.low, qp_thresholds.high) :
                                             ScalingSettings::kOff;
 
+    info.requested_resolution_alignment = encoder_.resolutionAlignment > 0 ?: 1;
+    info.apply_alignment_to_all_simulcast_layers = encoder_.applyAlignmentToAllSimulcastLayers;
     info.is_hardware_accelerated = true;
     info.has_internal_source = false;
     return info;