Android-在使用WebRTC发送到Wowza流媒体引擎之前旋转视频帧

我想使用WebRTC将视频从android摄像头传输到Wowza流媒体引擎（WSE）。当设备处于横向模式时，一切正常。然后，我尝试通过将设备置于纵向模式来传输数据

我在WSE播放器中注意到的第一件事是视频流被逆时针旋转了90度。我发现WebRTC在发送到WSE之前不会旋转来自onPreviewFrameAPI的每个视频帧，不幸的是，WSE至少到目前为止不支持任何旋转视频帧的机制

所以我检查了WebRTC android本机源代码，并对其进行了修改，以在发送到WSE之前旋转每个视频帧。现在我可以在WSE播放器中看到纵向模式的视频流

但它有一个问题，就是有时候视频流看起来很奇怪。请看下面的图片

我把相机放在固定的位置。WSE player第一次显示第一个，但有时会显示第二个

这是我更改的WebRTC源代码中的文件。 ~/webrtc/src/sdk/android/src/jni/androidvideotracksource.cc

void AndroidVideoTrackSource:：OnByteBufferFrameCaptured（const void*frame_数据，
整数长度，
整数宽度，
整数高度，
视频旋转，
int64（时间戳）{
RTC_DCHECK（摄像头_线程_检查器_.CalledOnValidThread（））；
int64\u t camera\u time\u us=时间戳\u ns/rtc:：KNumNanoSec微秒；
int64\u t翻译\u照相机\u时间\u我们=
时间戳对齐器TranslateTimestamp（摄像头时间戳，rtc:：TimeMicros（））；
int-u宽度；
内倾高度；
int裁剪宽度；
国际作物联合会高度；
int crop_x；
国际作物研究所；
如果（！自适应帧（宽度、高度、相机时间和自适应宽度），
&调整高度、裁剪宽度、裁剪高度和裁剪x，
&作物（y）{
返回；
}
const uint8_t*y_平面=静态（帧数据）；
常数8_t*uv_平面=y_平面+宽度*高度；
const int uv_width=（宽度+1）/2；
RTC检查（长度、宽度*高度+2*紫外线宽度*（（高度+1）/2））；
//只能裁剪偶数像素。
作物x&=~1；
作物y&=~1；
//只需修改指针即可进行裁剪。
y_平面+=宽度*裁剪y+裁剪x；
uv_平面+=uv_宽度*裁剪_y+裁剪_x；
rtc:：作用域_refptr缓冲区=
缓冲区\池\创建缓冲区（调整的\宽度、调整的\高度）；
nv12toi420\u刻度盘。nv12toi420刻度盘(
y_平面，宽度，uv_平面，uv_宽度*2，裁剪_宽度，裁剪_高度，
buffer->MutableDataY（），buffer->stripy（），
//交换U和V，因为我们有NV21，而不是NV12。
buffer->MutableDataV（），buffer->StrideV（），buffer->MutableDataU（），
缓冲区->步幅（），缓冲区->宽度（），缓冲区->高度（）；
//TODO:将I420机架顺时针旋转90度。
rtc:：作用域\u refptr旋转\u缓冲区=
I420Buffer:：Rotate（*buffer，kVideoRotation_90）；
OnFrame（视频帧（旋转的缓冲区、旋转、平移的摄像机、时间）；
}

我添加了这行代码来顺时针旋转I420帧90度

// TODO: Rotate I420 frame 90 degrees clockwise.
  rtc::scoped_refptr<I420Buffer> rotated_buffer =
      I420Buffer::Rotate(*buffer, kVideoRotation_90);

//TODO:将I420帧顺时针旋转90度。
rtc:：作用域\u refptr旋转\u缓冲区=
I420Buffer:：Rotate（*buffer，kVideoRotation_90）；

---

我将感谢任何帮助

我终于想出了解决这个问题的办法。以下是我的步骤： 第1步：确保将流媒体活动锁定为纵向 步骤2:在WebRTC android本机源代码中的文件中更改此方法 ~/webrtc/src/sdk/android/src/jni/androidvideotracksource.cc 原始版本：

void AndroidVideoTrackSource::OnByteBufferFrameCaptured(const void* frame_data,
                                                        int length,
                                                        int width,
                                                        int height,
                                                        VideoRotation rotation,
                                                        int64_t timestamp_ns) {
  RTC_DCHECK(camera_thread_checker_.CalledOnValidThread());

  int64_t camera_time_us = timestamp_ns / rtc::kNumNanosecsPerMicrosec;
  int64_t translated_camera_time_us =
      timestamp_aligner_.TranslateTimestamp(camera_time_us, rtc::TimeMicros());

  int adapted_width;
  int adapted_height;
  int crop_width;
  int crop_height;
  int crop_x;
  int crop_y;

  if (!AdaptFrame(width, height, camera_time_us, &adapted_width,
                  &adapted_height, &crop_width, &crop_height, &crop_x,
                  &crop_y)) {
    return;
  }

  const uint8_t* y_plane = static_cast<const uint8_t*>(frame_data);
  const uint8_t* uv_plane = y_plane + width * height;
  const int uv_width = (width + 1) / 2;

  RTC_CHECK_GE(length, width * height + 2 * uv_width * ((height + 1) / 2));

  // Can only crop at even pixels.
  crop_x &= ~1;
  crop_y &= ~1;
  // Crop just by modifying pointers.
  y_plane += width * crop_y + crop_x;
  uv_plane += uv_width * crop_y + crop_x;

  rtc::scoped_refptr<I420Buffer> buffer =
      buffer_pool_.CreateBuffer(adapted_width, adapted_height);

  nv12toi420_scaler_.NV12ToI420Scale(
      y_plane, width, uv_plane, uv_width * 2, crop_width, crop_height,
      buffer->MutableDataY(), buffer->StrideY(),
      // Swap U and V, since we have NV21, not NV12.
      buffer->MutableDataV(), buffer->StrideV(), buffer->MutableDataU(),
      buffer->StrideU(), buffer->width(), buffer->height());

  OnFrame(VideoFrame(rotated_buffer, rotation, translated_camera_time_us));
}

void AndroidVideoTrackSource::OnByteBufferFrameCaptured(const void* frame_data,
                                                        int length,
                                                        int width,
                                                        int height,
                                                        VideoRotation rotation,
                                                        int64_t timestamp_ns) {
  RTC_DCHECK(camera_thread_checker_.CalledOnValidThread());

  int64_t camera_time_us = timestamp_ns / rtc::kNumNanosecsPerMicrosec;
  int64_t translated_camera_time_us =
      timestamp_aligner_.TranslateTimestamp(camera_time_us, rtc::TimeMicros());

  int adapted_width;
  int adapted_height;
  int crop_width;
  int crop_height;
  int crop_x;
  int crop_y;

  if (!AdaptFrame(width, height, camera_time_us, &adapted_width,
                  &adapted_height, &crop_width, &crop_height, &crop_x,
                  &crop_y)) {
    return;
  }

  const uint8_t* y_plane = static_cast<const uint8_t*>(frame_data);
  const uint8_t* uv_plane = y_plane + width * height;
  const int uv_width = (width + 1) / 2;

  RTC_CHECK_GE(length, width * height + 2 * uv_width * ((height + 1) / 2));

  // Can only crop at even pixels.
  crop_x &= ~1;
  crop_y &= ~1;
  // Crop just by modifying pointers.
  y_plane += width * crop_y + crop_x;
  uv_plane += uv_width * crop_y + crop_x;

  rtc::scoped_refptr<I420Buffer> buffer =
      buffer_pool_.CreateBuffer(adapted_width, adapted_height);

  nv12toi420_scaler_.NV12ToI420Scale(
      y_plane, width, uv_plane, uv_width * 2, crop_width, crop_height,
      buffer->MutableDataY(), buffer->StrideY(),
      // Swap U and V, since we have NV21, not NV12.
      buffer->MutableDataV(), buffer->StrideV(), buffer->MutableDataU(),
      buffer->StrideU(), buffer->width(), buffer->height());

  // TODO: Comment out this line of code to apply custom code.
  // OnFrame(VideoFrame(buffer, rotation, translated_camera_time_us));

  // TODO: The custom code to rotate video frame before passing
  // to next layers of WebRTC.

  // Rotate I420 frame rotation degrees.
  // Value of the rotation is 90 or 270 based on camera orientation.
  rtc::scoped_refptr<I420Buffer> rotated_buffer =
      I420Buffer::Rotate(*buffer, rotation);

  // Make sure the I420 frame has valid side in portrait mode.
  rtc::scoped_refptr<I420Buffer> final_buffer =
      buffer_pool_.CreateBuffer(height, width);
  final_buffer->ScaleFrom(*rotated_buffer);

  // After rotating the I420 frame, set value of the rotation to 0.
  // This mean we do not want to rotate the frame in next layers anymore.
  rotation = kVideoRotation_0;

  // Pass processed frame to the next layers.
  OnFrame(VideoFrame(final_buffer, rotation, translated_camera_time_us));
}

void AndroidVideoTrackSource:：OnByteBufferFrameCaptured（const void*frame_数据，
整数长度，
整数宽度，
整数高度，
视频旋转，
int64（时间戳）{
RTC_DCHECK（摄像头_线程_检查器_.CalledOnValidThread（））；
int64\u t camera\u time\u us=时间戳\u ns/rtc:：KNumNanoSec微秒；
int64\u t翻译\u照相机\u时间\u我们=
时间戳对齐器TranslateTimestamp（摄像头时间戳，rtc:：TimeMicros（））；
int-u宽度；
内倾高度；
int裁剪宽度；
国际作物联合会高度；
int crop_x；
国际作物研究所；
如果（！自适应帧（宽度、高度、相机时间和自适应宽度），
&调整高度、裁剪宽度、裁剪高度和裁剪x，
&作物（y）{
返回；
}
const uint8_t*y_平面=静态（帧数据）；
常数8_t*uv_平面=y_平面+宽度*高度；
const int uv_width=（宽度+1）/2；
RTC检查（长度、宽度*高度+2*紫外线宽度*（（高度+1）/2））；
//只能裁剪偶数像素。
作物x&=~1；
作物y&=~1；
//只需修改指针即可进行裁剪。
y_平面+=宽度*裁剪y+裁剪x；
uv_平面+=uv_宽度*裁剪_y+裁剪_x；
rtc:：作用域_refptr缓冲区=
缓冲区\池\创建缓冲区（调整的\宽度、调整的\高度）；
nv12toi420\u刻度盘。nv12toi420刻度盘(
y_平面，宽度，uv_平面，uv_宽度*2，裁剪_宽度，裁剪_高度，
buffer->MutableDataY（），buffer->stripy（），
//交换U和V，因为我们有NV21，而不是NV12。
buffer->MutableDataV（），buffer->StrideV（），buffer->MutableDataU（），
缓冲区->步幅（），缓冲区->宽度（），缓冲区->高度（）；
OnFrame（视频帧（旋转的缓冲区、旋转、平移的摄像机、时间）；
}

修改版本：

void AndroidVideoTrackSource::OnByteBufferFrameCaptured(const void* frame_data,
                                                        int length,
                                                        int width,
                                                        int height,
                                                        VideoRotation rotation,
                                                        int64_t timestamp_ns) {
  RTC_DCHECK(camera_thread_checker_.CalledOnValidThread());

  int64_t camera_time_us = timestamp_ns / rtc::kNumNanosecsPerMicrosec;
  int64_t translated_camera_time_us =
      timestamp_aligner_.TranslateTimestamp(camera_time_us, rtc::TimeMicros());

  int adapted_width;
  int adapted_height;
  int crop_width;
  int crop_height;
  int crop_x;
  int crop_y;

  if (!AdaptFrame(width, height, camera_time_us, &adapted_width,
                  &adapted_height, &crop_width, &crop_height, &crop_x,
                  &crop_y)) {
    return;
  }

  const uint8_t* y_plane = static_cast<const uint8_t*>(frame_data);
  const uint8_t* uv_plane = y_plane + width * height;
  const int uv_width = (width + 1) / 2;

  RTC_CHECK_GE(length, width * height + 2 * uv_width * ((height + 1) / 2));

  // Can only crop at even pixels.
  crop_x &= ~1;
  crop_y &= ~1;
  // Crop just by modifying pointers.
  y_plane += width * crop_y + crop_x;
  uv_plane += uv_width * crop_y + crop_x;

  rtc::scoped_refptr<I420Buffer> buffer =
      buffer_pool_.CreateBuffer(adapted_width, adapted_height);

  nv12toi420_scaler_.NV12ToI420Scale(
      y_plane, width, uv_plane, uv_width * 2, crop_width, crop_height,
      buffer->MutableDataY(), buffer->StrideY(),
      // Swap U and V, since we have NV21, not NV12.
      buffer->MutableDataV(), buffer->StrideV(), buffer->MutableDataU(),
      buffer->StrideU(), buffer->width(), buffer->height());

  OnFrame(VideoFrame(rotated_buffer, rotation, translated_camera_time_us));
}

void AndroidVideoTrackSource::OnByteBufferFrameCaptured(const void* frame_data,
                                                        int length,
                                                        int width,
                                                        int height,
                                                        VideoRotation rotation,
                                                        int64_t timestamp_ns) {
  RTC_DCHECK(camera_thread_checker_.CalledOnValidThread());

  int64_t camera_time_us = timestamp_ns / rtc::kNumNanosecsPerMicrosec;
  int64_t translated_camera_time_us =
      timestamp_aligner_.TranslateTimestamp(camera_time_us, rtc::TimeMicros());

  int adapted_width;
  int adapted_height;
  int crop_width;
  int crop_height;
  int crop_x;
  int crop_y;

  if (!AdaptFrame(width, height, camera_time_us, &adapted_width,
                  &adapted_height, &crop_width, &crop_height, &crop_x,
                  &crop_y)) {
    return;
  }

  const uint8_t* y_plane = static_cast<const uint8_t*>(frame_data);
  const uint8_t* uv_plane = y_plane + width * height;
  const int uv_width = (width + 1) / 2;

  RTC_CHECK_GE(length, width * height + 2 * uv_width * ((height + 1) / 2));

  // Can only crop at even pixels.
  crop_x &= ~1;
  crop_y &= ~1;
  // Crop just by modifying pointers.
  y_plane += width * crop_y + crop_x;
  uv_plane += uv_width * crop_y + crop_x;

  rtc::scoped_refptr<I420Buffer> buffer =
      buffer_pool_.CreateBuffer(adapted_width, adapted_height);

  nv12toi420_scaler_.NV12ToI420Scale(
      y_plane, width, uv_plane, uv_width * 2, crop_width, crop_height,
      buffer->MutableDataY(), buffer->StrideY(),
      // Swap U and V, since we have NV21, not NV12.
      buffer->MutableDataV(), buffer->StrideV(), buffer->MutableDataU(),
      buffer->StrideU(), buffer->width(), buffer->height());

  // TODO: Comment out this line of code to apply custom code.
  // OnFrame(VideoFrame(buffer, rotation, translated_camera_time_us));

  // TODO: The custom code to rotate video frame before passing
  // to next layers of WebRTC.

  // Rotate I420 frame rotation degrees.
  // Value of the rotation is 90 or 270 based on camera orientation.
  rtc::scoped_refptr<I420Buffer> rotated_buffer =
      I420Buffer::Rotate(*buffer, rotation);

  // Make sure the I420 frame has valid side in portrait mode.
  rtc::scoped_refptr<I420Buffer> final_buffer =
      buffer_pool_.CreateBuffer(height, width);
  final_buffer->ScaleFrom(*rotated_buffer);

  // After rotating the I420 frame, set value of the rotation to 0.
  // This mean we do not want to rotate the frame in next layers anymore.
  rotation = kVideoRotation_0;

  // Pass processed frame to the next layers.
  OnFrame(VideoFrame(final_buffer, rotation, translated_camera_time_us));
}

void AndroidVideoTrackSource:：OnByteBufferFrameCaptured（const void*frame_数据