ObjC: Add implementationName for injectable codecs

BUG=webrtc:7924

Review-Url: https://codereview.webrtc.org/2987253003
Cr-Commit-Position: refs/heads/master@{#19213}

webrtc/sdk/objc/Framework/Classes/PeerConnection/RTCVideoCodecH264.mm

@@ -181,6 +181,10 @@ class H264VideoToolboxDecodeCompleteCallback : public webrtc::DecodedImageCallba
                                                                high:kHighH264QpThreshold];
 }
 
+- (NSString *)implementationName {
+  return @"VideoToolbox";
+}
+
 @end
 
 // Decoder.
@@ -247,6 +251,10 @@ class H264VideoToolboxDecodeCompleteCallback : public webrtc::DecodedImageCallba
       image, missingFrames, header.release(), &codecSpecificInfo, renderTimeMs);
 }
 
+- (NSString *)implementationName {
+  return @"VideoToolbox";
+}
+
 @end
 
 // Encoder factory.

webrtc/sdk/objc/Framework/Classes/VideoToolbox/objc_video_decoder_factory.mm

@@ -10,6 +10,7 @@
 
 #include "webrtc/sdk/objc/Framework/Classes/VideoToolbox/objc_video_decoder_factory.h"
 
+#import "NSString+StdString.h"
 #import "RTCVideoCodec+Private.h"
 #import "WebRTC/RTCVideoCodec.h"
 #import "WebRTC/RTCVideoCodecFactory.h"
@@ -30,7 +31,8 @@ namespace webrtc {
 namespace {
 class ObjCVideoDecoder : public VideoDecoder {
  public:
-  ObjCVideoDecoder(id<RTCVideoDecoder> decoder) : decoder_(decoder) {}
+  ObjCVideoDecoder(id<RTCVideoDecoder> decoder)
+      : decoder_(decoder), implementation_name_([decoder implementationName].stdString) {}
   ~ObjCVideoDecoder() { [decoder_ destroy]; }
 
   int32_t InitDecode(const VideoCodec *codec_settings, int32_t number_of_cores) {
@@ -85,8 +87,11 @@ class ObjCVideoDecoder : public VideoDecoder {
 
   int32_t Release() { return [decoder_ releaseDecoder]; }
 
+  const char *ImplementationName() const { return implementation_name_.c_str(); }
+
  private:
   id<RTCVideoDecoder> decoder_;
+  const std::string implementation_name_;
 };
 }  // namespace
 

webrtc/sdk/objc/Framework/Classes/VideoToolbox/objc_video_encoder_factory.mm

@@ -10,6 +10,9 @@
 
 #include "webrtc/sdk/objc/Framework/Classes/VideoToolbox/objc_video_encoder_factory.h"
 
+#include <string>
+
+#import "NSString+StdString.h"
 #import "RTCVideoCodec+Private.h"
 #import "WebRTC/RTCVideoCodec.h"
 #import "WebRTC/RTCVideoCodecFactory.h"
@@ -32,7 +35,8 @@ namespace webrtc {
 namespace {
 class ObjCVideoEncoder : public VideoEncoder {
  public:
-  ObjCVideoEncoder(id<RTCVideoEncoder> encoder) : encoder_(encoder) {}
+  ObjCVideoEncoder(id<RTCVideoEncoder> encoder)
+      : encoder_(encoder), implementation_name_([encoder implementationName].stdString) {}
   ~ObjCVideoEncoder() { [encoder_ destroy]; }
 
   int32_t InitEncode(const VideoCodec *codec_settings,
@@ -118,8 +122,11 @@ class ObjCVideoEncoder : public VideoEncoder {
         ScalingSettings(false /* enabled */);
   }
 
+  const char *ImplementationName() const { return implementation_name_.c_str(); }
+
  private:
   id<RTCVideoEncoder> encoder_;
+  const std::string implementation_name_;
 };
 }  // namespace
 

webrtc/sdk/objc/Framework/Headers/WebRTC/RTCVideoCodec.h

@@ -128,14 +128,13 @@ RTC_EXPORT
     codecSpecificInfo:(id<RTCCodecSpecificInfo>)info
            frameTypes:(NSArray<NSNumber *> *)frameTypes;
 - (BOOL)setBitrate:(uint32_t)bitrateKbit framerate:(uint32_t)framerate;
+- (NSString *)implementationName;
 
 /** Returns QP scaling settings for encoder. The quality scaler adjusts the resolution in order to
  *  keep the QP from the encoded images within the given range. Returning nil from this function
  *  disables quality scaling. */
 - (RTCVideoEncoderQpThresholds *)scalingSettings;
 
-// TODO(andersc): Add implementationName method.
-
 @end
 
 /** Protocol for decoder implementations. */
@@ -152,8 +151,7 @@ RTC_EXPORT
     fragmentationHeader:(RTCRtpFragmentationHeader *)fragmentationHeader
       codecSpecificInfo:(__nullable id<RTCCodecSpecificInfo>)info
            renderTimeMs:(int64_t)renderTimeMs;
-
-// TODO(andersc): Add implementationName method.
+- (NSString *)implementationName;
 
 @end