纵向模式下的MediaRecorder视频捕获 [英] MediaRecorder video capturing in portrait mode

问题描述

我正在尝试制作自定义视频应用. Iwork仅使用清单 2.2(API 8)中的设置.

I'm try to make custom video app. Iwork using settings in manifest 2.2 only (API 8).

一切顺利，但我不明白为什么肖像模式视频与lanscape模式视频没有区别.

All goes well but I don't understand why portrait mode video does not differ from lanscape one.

要检测设备更改的方向，我在surfaceChanged()中使用此代码

To make detection of device changed orientation I use this code within surfaceChanged()

        if (mCamera != null) {

        Camera.Parameters p = mCamera.getParameters();

        try {
            mCamera.stopPreview();
        } catch (Exception e) {
            // TODO: handle exception
        }

        int previewWidth = 0;
        int previewHeight = 0;

        if (mPreviewSize != null) {
            Display display = ((WindowManager) mContext.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
            int rotation = display.getRotation();

            switch (rotation) {
            case Surface.ROTATION_0:
                previewWidth = mPreviewSize.height;
                previewHeight = mPreviewSize.width;
                mCamera.setDisplayOrientation(90);
                break;

            case Surface.ROTATION_90:
                previewWidth = mPreviewSize.width;
                previewHeight = mPreviewSize.height;
                mCamera.setDisplayOrientation(0);
                break;

            case Surface.ROTATION_180:
                previewWidth = mPreviewSize.height;
                previewHeight = mPreviewSize.width;
                mCamera.setDisplayOrientation(270);
                break;

            case Surface.ROTATION_270:
                previewWidth = mPreviewSize.width;
                previewHeight = mPreviewSize.height;
                mCamera.setDisplayOrientation(180);
                break;
            }

            p.setPreviewSize(previewWidth, previewHeight);
            mCamera.setParameters(p);
        }
    try {
        mCamera.setPreviewDisplay(mHolder);
        mCamera.startPreview();
    } catch (Exception e) {
        Log.d(TAG, "Cannot start preview.", e);
    }
}

像魅力一样工作.如果我旋转设备表面更改方向，请调用surfaceChanged，将相机设置为适当的DisplayRotation.

Works like a charm. If I rotate device surface change orientation, calling surfaceChanged, where camera is set to appropriate DisplayRotation.

问题是如何稍后确定是以lanscape模式还是纵向模式捕获的视频.当我得到所有视频时，都是以横向拍摄的.它不依赖于setDisplayOrientation，后者仅影响预览过程.

The question is how to determine later if the video captured either in lanscape mode or in portrait one. As I got all the videos are captured in landscape orientation. It does not depend of setDisplayOrientation which affect only preview process.

我也发现了这个问题，我发现如果使用标准的Camera应用程序，它会向视频文件中写入特殊标签(在MediaInfo中可见):旋转:90 用于拍摄人像.

Also exploring the problem I noticed that if to use standard Camera app it writes special tag to video file (seen in MediaInfo): Rotation : 90 for the portrait captured videos.

但是MediaRecorder类没有.

But MediaRecorder class does not.

似乎是问题所在.有人要解决这个问题吗?

Seems that is the problem. Anybody got to solve this?

推荐答案

找到了！ 确实，您可以更改预览，可以为视频添加标签，但是无法实际更改视频...(可能是速度问题或其他原因)

Found it ! Indeed, you can change the preview, you can tag the video, but there's no way to actually change the video... (maybe a speed issue or something)

camera.setDisplayOrientation(90);

要旋转预览，然后

recorder.setOrientationHint(90);

要将视频标记为旋转90°，那么手机在阅读时会自动旋转视频.

To tag the video as having a 90° rotation, then the phone will automatically rotate it when reading.

所以您要做的就是

            camera = Camera.open();
        //Set preview with a 90° ortientation
        camera.setDisplayOrientation(90);
        camera.unlock();

        holder = getHolder();
        holder.addCallback(this);
        holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

        recorder = new MediaRecorder();
        recorder.setCamera(camera);
        recorder.setAudioSource(MediaRecorder.AudioSource.MIC);
        recorder.setVideoSource(MediaRecorder.VideoSource.DEFAULT);
        recorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
        recorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
        recorder.setVideoEncoder(MediaRecorder.VideoEncoder.MPEG_4_SP);
        recorder.setOutputFile(getVideoFolder()+rnd.nextString()+".mp4");
        recorder.setPreviewDisplay(holder.getSurface());
        //Tags the video with a 90° angle in order to tell the phone how to display it
        recorder.setOrientationHint(90);

        if (recorder != null) {
            try {
                recorder.prepare();
            } catch (IllegalStateException e) {
                Log.e("IllegalStateException", e.toString());
            } catch (IOException e) {
                Log.e("IOException", e.toString());
            }
        }

        recorder.start();

希望有帮助；-)

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