iOS HW H264 support.

webrtc/modules/video_coding/codecs/h264/h264.mm

+/*
+ *  Copyright (c) 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.
+ *
+ */
+
+#include "webrtc/modules/video_coding/codecs/h264/include/h264.h"
+
+#if defined(WEBRTC_IOS)
+#import <UIKit/UIKit.h>
+#endif
+
+#if defined(WEBRTC_IOS) || defined(WEBRTC_MAC)
+#include "webrtc/modules/video_coding/codecs/h264/h264_video_toolbox_decoder.h"
+#include "webrtc/modules/video_coding/codecs/h264/h264_video_toolbox_encoder.h"
+#endif
+
+namespace webrtc {
+
+H264Encoder* H264Encoder::Create() {
+#if defined(WEBRTC_VIDEO_TOOLBOX_SUPPORTED)
+#if defined(WEBRTC_IOS)
+  // Bail if we aren't actually running on an iOS8 device.

[pbos-webrtc, 2015/06/23 19:13:56]

I do not believe we handle "return nullptr;" well at all outside this function.
If we claim to support H264 through cricket::VideoCodec (SDP) we must also
support it. You need to turn this into a query so that we can actually check
whether the encoder is supported or not before trying to create them.

[tkchin_webrtc, 2015/06/24 23:21:14]

Done.

+  if ([[[UIDevice currentDevice] systemVersion] doubleValue] < 8.0) {
+    return nullptr;
+  }
+#endif  // WEBRTC_IOS
+  return new H264VideoToolboxEncoder();
+#else
+  return nullptr;
+#endif  // WEBRTC_VIDEO_TOOLBOX_SUPPORTED
+}
+
+H264Decoder* H264Decoder::Create() {
+#if defined(WEBRTC_VIDEO_TOOLBOX_SUPPORTED)
+#if defined(WEBRTC_IOS)
+  // Bail if we aren't actually running on an iOS8 device.
+  if ([[[UIDevice currentDevice] systemVersion] doubleValue] < 8.0) {
+    return nullptr;
+  }
+#endif
+  return new H264VideoToolboxDecoder();
+#else   // WEBRTC_IOS
+  return nullptr;
+#endif  // WEBRTC_VIDEO_TOOLBOX_SUPPORTED
+}
+
+}  // namespace webrtc