Enable building WebRTC without built-in software codecs

This CL adds a GN build flag to include builtin software codecs
(enabled by default).

When setting the flag to false, libvpx can also be excluded. The
benefit is that the resulting binary is smaller.

Replaces https://webrtc-review.googlesource.com/c/src/+/29203

Bug: webrtc:7925
Change-Id: Id330ea8a43169e449ee139eca18e4557cc932e10
Reviewed-on: https://webrtc-review.googlesource.com/36340
Commit-Queue: Anders Carlsson <andersc@webrtc.org>
Reviewed-by: Patrik Höglund <phoglund@webrtc.org>
Reviewed-by: Taylor Brandstetter <deadbeef@webrtc.org>
Reviewed-by: Erik Språng <sprang@webrtc.org>
Reviewed-by: Magnus Jedvert <magjed@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#21818}

sdk/objc/Framework/Classes/PeerConnection/RTCDefaultVideoDecoderFactory.m

@@ -11,21 +11,25 @@
 #import "WebRTC/RTCVideoCodecFactory.h"
 
 #import "WebRTC/RTCVideoCodecH264.h"
+#if defined(USE_BUILTIN_SW_CODECS)
 #import "WebRTC/RTCVideoDecoderVP8.h"
 #if !defined(RTC_DISABLE_VP9)
 #import "WebRTC/RTCVideoDecoderVP9.h"
 #endif
+#endif
 
 @implementation RTCDefaultVideoDecoderFactory
 
 - (id<RTCVideoDecoder>)createDecoder:(RTCVideoCodecInfo *)info {
   if ([info.name isEqualToString:kRTCVideoCodecH264Name]) {
     return [[RTCVideoDecoderH264 alloc] init];
+#if defined(USE_BUILTIN_SW_CODECS)
   } else if ([info.name isEqualToString:kRTCVideoCodecVp8Name]) {
     return [RTCVideoDecoderVP8 vp8Decoder];
 #if !defined(RTC_DISABLE_VP9)
   } else if ([info.name isEqualToString:kRTCVideoCodecVp9Name]) {
     return [RTCVideoDecoderVP9 vp9Decoder];
+#endif
 #endif
   }
 
@@ -35,9 +39,11 @@
 - (NSArray<RTCVideoCodecInfo *> *)supportedCodecs {
   return @[
     [[RTCVideoCodecInfo alloc] initWithName:kRTCVideoCodecH264Name],
+#if defined(USE_BUILTIN_SW_CODECS)
     [[RTCVideoCodecInfo alloc] initWithName:kRTCVideoCodecVp8Name],
 #if !defined(RTC_DISABLE_VP9)
-    [[RTCVideoCodecInfo alloc] initWithName:kRTCVideoCodecVp9Name]
+    [[RTCVideoCodecInfo alloc] initWithName:kRTCVideoCodecVp9Name],
+#endif
 #endif
   ];
 }

sdk/objc/Framework/Classes/PeerConnection/RTCDefaultVideoEncoderFactory.m

@@ -12,10 +12,12 @@
 
 #import "WebRTC/RTCVideoCodec.h"
 #import "WebRTC/RTCVideoCodecH264.h"
+#if defined(USE_BUILTIN_SW_CODECS)
 #import "WebRTC/RTCVideoEncoderVP8.h"
 #if !defined(RTC_DISABLE_VP9)
 #import "WebRTC/RTCVideoEncoderVP9.h"
 #endif
+#endif
 
 @implementation RTCDefaultVideoEncoderFactory
 
@@ -40,29 +42,36 @@
       [[RTCVideoCodecInfo alloc] initWithName:kRTCVideoCodecH264Name
                                    parameters:constrainedBaselineParams];
 
+#if defined(USE_BUILTIN_SW_CODECS)
   RTCVideoCodecInfo *vp8Info = [[RTCVideoCodecInfo alloc] initWithName:kRTCVideoCodecVp8Name];
 
 #if !defined(RTC_DISABLE_VP9)
   RTCVideoCodecInfo *vp9Info = [[RTCVideoCodecInfo alloc] initWithName:kRTCVideoCodecVp9Name];
 #endif
-
-  return @[ constrainedHighInfo,
-            constrainedBaselineInfo,
-            vp8Info,
-#if !defined(RTC_DISABLE_VP9)
-            vp9Info
 #endif
-            ];
+
+  return @[
+    constrainedHighInfo,
+    constrainedBaselineInfo,
+#if defined(USE_BUILTIN_SW_CODECS)
+    vp8Info,
+#if !defined(RTC_DISABLE_VP9)
+    vp9Info,
+#endif
+#endif
+  ];
 }
 
 - (id<RTCVideoEncoder>)createEncoder:(RTCVideoCodecInfo *)info {
   if ([info.name isEqualToString:kRTCVideoCodecH264Name]) {
     return [[RTCVideoEncoderH264 alloc] initWithCodecInfo:info];
+#if defined(USE_BUILTIN_SW_CODECS)
   } else if ([info.name isEqualToString:kRTCVideoCodecVp8Name]) {
     return [RTCVideoEncoderVP8 vp8Encoder];
 #if !defined(RTC_DISABLE_VP9)
   } else if ([info.name isEqualToString:kRTCVideoCodecVp9Name]) {
     return [RTCVideoEncoderVP9 vp9Encoder];
+#endif
 #endif
   }
 

sdk/objc/Framework/Classes/PeerConnection/RTCPeerConnectionFactory+Native.h

@@ -23,12 +23,14 @@ class AudioProcessing;
 
 }  // namespace webrtc
 
+#if defined(USE_BUILTIN_SW_CODECS)
 namespace cricket {
 
 class WebRtcVideoEncoderFactory;
 class WebRtcVideoDecoderFactory;
 
 }  // namespace cricket
+#endif
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -56,6 +58,7 @@ NS_ASSUME_NONNULL_BEGIN
                             audioProcessingModule:
                                 (rtc::scoped_refptr<webrtc::AudioProcessing>)audioProcessingModule;
 
+#if defined(USE_BUILTIN_SW_CODECS)
 /* Initialize object with legacy injectable native audio/video encoder/decoder factories
    TODO(andersc): Remove this when backwards compatiblity is no longer needed.
  */
@@ -67,6 +70,7 @@ NS_ASSUME_NONNULL_BEGIN
       legacyNativeVideoEncoderFactory:(cricket::WebRtcVideoEncoderFactory*)videoEncoderFactory
       legacyNativeVideoDecoderFactory:(cricket::WebRtcVideoDecoderFactory*)videoDecoderFactory
                     audioDeviceModule:(nullable webrtc::AudioDeviceModule *)audioDeviceModule;
+#endif
 
 @end
 

sdk/objc/Framework/Classes/PeerConnection/RTCPeerConnectionFactory.mm

@@ -58,6 +58,17 @@
 - (instancetype)init {
 #ifdef HAVE_NO_MEDIA
   return [self initWithNoMedia];
+#elif !defined(USE_BUILTIN_SW_CODECS)
+  return [self initWithNativeAudioEncoderFactory:webrtc::CreateBuiltinAudioEncoderFactory()
+                       nativeAudioDecoderFactory:webrtc::CreateBuiltinAudioDecoderFactory()
+                       nativeVideoEncoderFactory:std::unique_ptr<webrtc::VideoEncoderFactory>(
+                                                     new webrtc::ObjCVideoEncoderFactory(
+                                                         [[RTCVideoEncoderFactoryH264 alloc] init]))
+                       nativeVideoDecoderFactory:std::unique_ptr<webrtc::VideoDecoderFactory>(
+                                                     new webrtc::ObjCVideoDecoderFactory(
+                                                         [[RTCVideoDecoderFactoryH264 alloc] init]))
+                               audioDeviceModule:nullptr
+                           audioProcessingModule:nullptr];
 #else
   return [self initWithNativeAudioEncoderFactory:webrtc::CreateBuiltinAudioEncoderFactory()
                        nativeAudioDecoderFactory:webrtc::CreateBuiltinAudioDecoderFactory()
@@ -139,6 +150,7 @@
   return [self initWithNoMedia];
 #else
   if (self = [self initNative]) {
+#if defined(USE_BUILTIN_SW_CODECS)
     if (!videoEncoderFactory) {
       auto legacy_video_encoder_factory = rtc::MakeUnique<webrtc::ObjCVideoEncoderFactory>(
           [[RTCVideoEncoderFactoryH264 alloc] init]);
@@ -149,6 +161,7 @@
           [[RTCVideoDecoderFactoryH264 alloc] init]);
       videoDecoderFactory = ConvertVideoDecoderFactory(std::move(legacy_video_decoder_factory));
     }
+#endif
     _nativeFactory = webrtc::CreatePeerConnectionFactory(_networkThread.get(),
                                                          _workerThread.get(),
                                                          _signalingThread.get(),
@@ -165,6 +178,7 @@
 #endif
 }
 
+#if defined(USE_BUILTIN_SW_CODECS)
 - (instancetype)
     initWithNativeAudioEncoderFactory:
         (rtc::scoped_refptr<webrtc::AudioEncoderFactory>)audioEncoderFactory
@@ -190,6 +204,7 @@
   return self;
 #endif
 }
+#endif
 
 - (RTCAudioSource *)audioSourceWithConstraints:(nullable RTCMediaConstraints *)constraints {
   std::unique_ptr<webrtc::MediaConstraints> nativeConstraints;