Adjust for initial cropping when adapting frame.

webrtc/sdk/objc/Framework/Classes/Video/objcvideotracksource.mm

 /*
  *  Copyright (c) 2017 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.
  */
 
@@ skipping 36 matching lines @@
     buffer = new rtc::RefCountedObject<ObjCFrameBuffer>(frame.buffer);
   } else if ([frame.buffer isKindOfClass:[RTCCVPixelBuffer class]]) {
     // Adapted CVPixelBuffer frame.
     RTCCVPixelBuffer *rtcPixelBuffer = (RTCCVPixelBuffer *)frame.buffer;
     buffer = new rtc::RefCountedObject<ObjCFrameBuffer>([[RTCCVPixelBuffer alloc]
         initWithPixelBuffer:rtcPixelBuffer.pixelBuffer
                adaptedWidth:adapted_width
               adaptedHeight:adapted_height
                   cropWidth:crop_width
                  cropHeight:crop_height
-                      cropX:crop_x
-                      cropY:crop_y]);
+                      cropX:crop_x + rtcPixelBuffer.cropX
+                      cropY:crop_y + rtcPixelBuffer.cropY]);
   } else {
     // Adapted I420 frame.
     // TODO(magjed): Optimize this I420 path.
     rtc::scoped_refptr<I420Buffer> i420_buffer = I420Buffer::Create(adapted_width, adapted_height);
     buffer = new rtc::RefCountedObject<ObjCFrameBuffer>(frame.buffer);
     i420_buffer->CropAndScaleFrom(*buffer->ToI420(), crop_x, crop_y, crop_width, crop_height);
     buffer = i420_buffer;
   }
 
   // Applying rotation is only supported for legacy reasons and performance is
   // not critical here.
   webrtc::VideoRotation rotation = static_cast<webrtc::VideoRotation>(frame.rotation);
   if (apply_rotation() && rotation != kVideoRotation_0) {
     buffer = I420Buffer::Rotate(*buffer->ToI420(), rotation);
     rotation = kVideoRotation_0;
   }
 
   OnFrame(webrtc::VideoFrame(buffer, rotation, translated_timestamp_us));
 }
 
 }  // namespace webrtc