那些遇到过的问题

How to have similar mechanism of center-crop on ExoPlayer's PlayerView , but not on the center?

and*_*per 19 android crop scale exoplayer

Background

We record a video of the user's face, and usually the face is located at the upper half of the video.

Later we wish to view the video, but the aspect ratio of the PlayerView might be different than the one of the video, so there needs to be some scaling and cropping.

The problem

我发现缩放PlayerView它的唯一方法是将它显示在它所拥有的整个空间中,但保持纵横比(当然需要在需要时进行裁剪),是通过使用app:resize_mode="zoom".以下是中心裁剪的示例:http://s000.tinyupload.com/？file_id = 00574047057406286563.显示内容的视图具有相似的宽高比越多,所需的裁剪越少.

但这仅适用于中心,这意味着它需要0.5x0.5的视频点,并从那一点开始进行缩放.这导致许多丢失视频重要内容的情况.

例如,如果我们有一个以纵向拍摄的视频,并且我们有一个方形的PlayerView并想要显示顶部区域,那么这将是可见的部分:

PlayerView

当然,如果内容本身是正方形,并且视图也是正方形,则应该显示整个内容,而不进行裁剪.

我试过的

我试过通过Internet,StackOverflow(这里)和Github搜索,但我找不到怎么做.我发现的唯一线索是关于AspectRatioFrameLayout和AspectRatioTextureView,但我没有找到如何将它们用于此任务,如果它甚至可能的话.

我被告知(这里)我应该使用普通TextureView,并直接提供它SimpleExoPlayer使用SimpleExoPlayer.setVideoTextureView.并使用它设置一个特殊的转换TextureView.setTransform.

After a lot of trying what is best to use (and looking at video-crop repository , SuperImageView repository , and JCropImageView repository which have examples of scale/crop of ImageView and video), I've published a working sample that seems to show the video correctly, but I'm still not sure about it, as I also use an ImageView that's shown on top of it before it starts playing (to have a nicer transition instead of black content).

Here's the current code:

class MainActivity : AppCompatActivity() {
    private val imageResId = R.drawable.test
    private val videoResId = R.raw.test
    private val percentageY = 0.2f
    private var player: SimpleExoPlayer? = null


    override fun onCreate(savedInstanceState: Bundle?) {
        window.setBackgroundDrawable(ColorDrawable(0xff000000.toInt()))
        super.onCreate(savedInstanceState)
        if (cache == null) {
            cache = SimpleCache(File(cacheDir, "media"), LeastRecentlyUsedCacheEvictor(MAX_PREVIEW_CACHE_SIZE_IN_BYTES))
        }
        setContentView(R.layout.activity_main)
//        imageView.visibility = View.INVISIBLE
        imageView.setImageResource(imageResId)
        imageView.doOnPreDraw {
            imageView.imageMatrix = prepareMatrixForImageView(imageView, imageView.drawable.intrinsicWidth.toFloat(), imageView.drawable.intrinsicHeight.toFloat())
//            imageView.imageMatrix = prepareMatrix(imageView, imageView.drawable.intrinsicWidth.toFloat(), imageView.drawable.intrinsicHeight.toFloat())
//            imageView.visibility = View.VISIBLE
        }
    }

    override fun onStart() {
        super.onStart()
        playVideo()
    }

    private fun prepareMatrix(view: View, contentWidth: Float, contentHeight: Float): Matrix {
        var scaleX = 1.0f
        var scaleY = 1.0f
        val viewWidth = view.measuredWidth.toFloat()
        val viewHeight = view.measuredHeight.toFloat()
        Log.d("AppLog", "viewWidth $viewWidth viewHeight $viewHeight contentWidth:$contentWidth contentHeight:$contentHeight")
        if (contentWidth > viewWidth && contentHeight > viewHeight) {
            scaleX = contentWidth / viewWidth
            scaleY = contentHeight / viewHeight
        } else if (contentWidth < viewWidth && contentHeight < viewHeight) {
            scaleY = viewWidth / contentWidth
            scaleX = viewHeight / contentHeight
        } else if (viewWidth > contentWidth)
            scaleY = viewWidth / contentWidth / (viewHeight / contentHeight)
        else if (viewHeight > contentHeight)
            scaleX = viewHeight / contentHeight / (viewWidth / contentWidth)
        val matrix = Matrix()
        val pivotPercentageX = 0.5f
        val pivotPercentageY = percentageY

        matrix.setScale(scaleX, scaleY, viewWidth * pivotPercentageX, viewHeight * pivotPercentageY)
        return matrix
    }

    private fun prepareMatrixForVideo(view: View, contentWidth: Float, contentHeight: Float): Matrix {
        val msWidth = view.measuredWidth
        val msHeight = view.measuredHeight
        val matrix = Matrix()
        matrix.setScale(1f, (contentHeight / contentWidth) * (msWidth.toFloat() / msHeight), msWidth / 2f, percentageY * msHeight) /*,msWidth/2f,msHeight/2f*/
        return matrix
    }

    private fun prepareMatrixForImageView(view: View, contentWidth: Float, contentHeight: Float): Matrix {
        val dw = contentWidth
        val dh = contentHeight
        val msWidth = view.measuredWidth
        val msHeight = view.measuredHeight
//        Log.d("AppLog", "viewWidth $msWidth viewHeight $msHeight contentWidth:$contentWidth contentHeight:$contentHeight")
        val scalew = msWidth.toFloat() / dw
        val theoryh = (dh * scalew).toInt()
        val scaleh = msHeight.toFloat() / dh
        val theoryw = (dw * scaleh).toInt()
        val scale: Float
        var dx = 0
        var dy = 0
        if (scalew > scaleh) { // fit width
            scale = scalew
//            dy = ((msHeight - theoryh) * 0.0f + 0.5f).toInt() // + 0.5f for rounding
        } else {
            scale = scaleh
            dx = ((msWidth - theoryw) * 0.5f + 0.5f).toInt() // + 0.5f for rounding
        }
        dy = ((msHeight - theoryh) * percentageY + 0.5f).toInt() // + 0.5f for rounding
        val matrix = Matrix()
//        Log.d("AppLog", "scale:$scale dx:$dx dy:$dy")
        matrix.setScale(scale, scale)
        matrix.postTranslate(dx.toFloat(), dy.toFloat())
        return matrix
    }

    private fun playVideo() {
        player = ExoPlayerFactory.newSimpleInstance(this@MainActivity, DefaultTrackSelector())
        player!!.setVideoTextureView(textureView)
        player!!.addVideoListener(object : VideoListener {
            override fun onVideoSizeChanged(width: Int, height: Int, unappliedRotationDegrees: Int, pixelWidthHeightRatio: Float) {
                super.onVideoSizeChanged(width, height, unappliedRotationDegrees, pixelWidthHeightRatio)
                Log.d("AppLog", "onVideoSizeChanged: $width $height")
                val videoWidth = if (unappliedRotationDegrees % 180 == 0) width else height
                val videoHeight = if (unappliedRotationDegrees % 180 == 0) height else width
                val matrix = prepareMatrixForVideo(textureView, videoWidth.toFloat(), videoHeight.toFloat())
                textureView.setTransform(matrix)
            }

            override fun onRenderedFirstFrame() {
                Log.d("AppLog", "onRenderedFirstFrame")
                player!!.removeVideoListener(this)
//                imageView.animate().alpha(0f).setDuration(5000).start()
                imageView.visibility = View.INVISIBLE
            }
        })
        player!!.volume = 0f
        player!!.repeatMode = Player.REPEAT_MODE_ALL
        player!!.playRawVideo(this, videoResId)
        player!!.playWhenReady = true
        //        player!!.playVideoFromUrl(this, "https://sample-videos.com/video123/mkv/240/big_buck_bunny_240p_20mb.mkv", cache!!)
        //        player!!.playVideoFromUrl(this, "https://sample-videos.com/video123/mkv/720/big_buck_bunny_720p_1mb.mkv", cache!!)
        //        player!!.playVideoFromUrl(this@MainActivity, "https://sample-videos.com/video123/mkv/720/big_buck_bunny_720p_1mb.mkv")
    }

    override fun onStop() {
        super.onStop()
        player!!.setVideoTextureView(null)
        //        playerView.player = null
        player!!.release()
        player = null
    }

    companion object {
        const val MAX_PREVIEW_CACHE_SIZE_IN_BYTES = 20L * 1024L * 1024L
        var cache: com.google.android.exoplayer2.upstream.cache.Cache? = null

        @JvmStatic
        fun getUserAgent(context: Context): String {
            val packageManager = context.packageManager
            val info = packageManager.getPackageInfo(context.packageName, 0)
            val appName = info.applicationInfo.loadLabel(packageManager).toString()
            return Util.getUserAgent(context, appName)
        }
    }

    fun SimpleExoPlayer.playRawVideo(context: Context, @RawRes rawVideoRes: Int) {
        val dataSpec = DataSpec(RawResourceDataSource.buildRawResourceUri(rawVideoRes))
        val rawResourceDataSource = RawResourceDataSource(context)
        rawResourceDataSource.open(dataSpec)
        val factory: DataSource.Factory = DataSource.Factory { rawResourceDataSource }
        prepare(LoopingMediaSource(ExtractorMediaSource.Factory(factory).createMediaSource(rawResourceDataSource.uri)))
    }

    fun SimpleExoPlayer.playVideoFromUrl(context: Context, url: String, cache: Cache? = null) = playVideoFromUri(context, Uri.parse(url), cache)

    fun SimpleExoPlayer.playVideoFile(context: Context, file: File) = playVideoFromUri(context, Uri.fromFile(file))

    fun SimpleExoPlayer.playVideoFromUri(context: Context, uri: Uri, cache: Cache? = null) {
        val factory = if (cache != null)
            CacheDataSourceFactory(cache, DefaultHttpDataSourceFactory(getUserAgent(context)))
        else
            DefaultDataSourceFactory(context, MainActivity.getUserAgent(context))
        val mediaSource = ExtractorMediaSource.Factory(factory).createMediaSource(uri)
        prepare(mediaSource)
    }
}
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在我遇到目前的情况之前,我遇到了各种各样的问题,并且我已经多次更新了这个问题.现在它甚至适用于我所谈论的百分比,所以如果我愿意,我可以将其设置为视频顶部的20%.但是,我仍然认为它有可能出现问题,因为当我尝试将其设置为50%时,我注意到内容可能不适合整个View.

我甚至查看了ImageView的源代码(这里),看看如何使用中心裁剪.当应用于ImageView时,它仍然可以作为中心裁剪,但是当我在视频上使用相同的技术时,它给了我一个非常错误的结果.

问题

我的目标是显示ImageView和视频,以便它可以平滑地从静态图像转换为视频.所有这一切都同时具有从顶部20%的顶级作物(例如).我在这里发布了一个示例项目,试用它并分享我发现的内容.

所以现在我的问题是为什么这对于imageView和/或视频似乎不太好用:

  1. 事实证明,我尝试过的矩阵创作都不适用于ImageView或视频.这究竟是什么问题？如何更改它们才能看起来一样？例如,从前20%进行规模裁剪？

  2. 我尝试使用两者的精确矩阵,但似乎每个都需要不同,即使两者具有完全相同的大小和内容大小.为什么我需要每个不同的矩阵？

编辑:在回答了这个问题之后,我决定制作一个如何使用它的小样本(这里有 Github存储库):

import android.content.Context
import android.graphics.Matrix
import android.graphics.PointF
import android.net.Uri
import android.os.Bundle
import android.view.TextureView
import android.view.View
import androidx.annotation.RawRes
import androidx.appcompat.app.AppCompatActivity
import androidx.core.view.doOnPreDraw
import com.google.android.exoplayer2.ExoPlayerFactory
import com.google.android.exoplayer2.Player
import com.google.android.exoplayer2.SimpleExoPlayer
import com.google.android.exoplayer2.source.ExtractorMediaSource
import com.google.android.exoplayer2.source.LoopingMediaSource
import com.google.android.exoplayer2.trackselection.DefaultTrackSelector
import com.google.android.exoplayer2.upstream.*
import com.google.android.exoplayer2.upstream.cache.Cache
import com.google.android.exoplayer2.upstream.cache.CacheDataSourceFactory
import com.google.android.exoplayer2.upstream.cache.LeastRecentlyUsedCacheEvictor
import com.google.android.exoplayer2.upstream.cache.SimpleCache
import com.google.android.exoplayer2.util.Util
import com.google.android.exoplayer2.video.VideoListener
import kotlinx.android.synthetic.main.activity_main.*
import java.io.File

// https://stackoverflow.com/questions/54216273/how-to-have-similar-mechanism-of-center-crop-on-exoplayers-playerview-but-not
class MainActivity : AppCompatActivity() {
    companion object {
        private val FOCAL_POINT = PointF(0.5f, 0.2f)
        private const val IMAGE_RES_ID = R.drawable.test
        private const val VIDEO_RES_ID = R.raw.test
        private var cache: Cache? = null
        private const val MAX_PREVIEW_CACHE_SIZE_IN_BYTES = 20L * 1024L * 1024L

        @JvmStatic
        fun getUserAgent(context: Context): String {
            val packageManager = context.packageManager
            val info = packageManager.getPackageInfo(context.packageName, 0)
            val appName = info.applicationInfo.loadLabel(packageManager).toString()
            return Util.getUserAgent(context, appName)
        }
    }

    private var player: SimpleExoPlayer? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        if (cache == null)
            cache = SimpleCache(File(cacheDir, "media"), LeastRecentlyUsedCacheEvictor(MAX_PREVIEW_CACHE_SIZE_IN_BYTES))
        //        imageView.visibility = View.INVISIBLE
        imageView.setImageResource(IMAGE_RES_ID)
    }

    private fun prepareMatrix(view: View, mediaWidth: Float, mediaHeight: Float, focalPoint: PointF): Matrix? {
        if (view.visibility == View.GONE)
            return null
        val viewHeight = (view.height - view.paddingTop - view.paddingBottom).toFloat()
        val viewWidth = (view.width - view.paddingStart - view.paddingEnd).toFloat()
        if (viewWidth <= 0 || viewHeight <= 0)
            return null
        val matrix = Matrix()
        if (view is TextureView)
        // Restore true media size for further manipulation.
            matrix.setScale(mediaWidth / viewWidth, mediaHeight / viewHeight)
        val scaleFactorY = viewHeight / mediaHeight
        val scaleFactor: Float
        var px = 0f
        var py = 0f
        if (mediaWidth * scaleFactorY >= viewWidth) {
            // Fit height
            scaleFactor = scaleFactorY
            px = -(mediaWidth * scaleFactor - viewWidth) * focalPoint.x / (1 - scaleFactor)
        } else {
            // Fit width
            scaleFactor = viewWidth / mediaWidth
            py = -(mediaHeight * scaleFactor - viewHeight) * focalPoint.y / (1 - scaleFactor)
        }
        matrix.postScale(scaleFactor, scaleFactor, px, py)
        return matrix
    }

    private fun playVideo() {
        player = ExoPlayerFactory.newSimpleInstance(this@MainActivity, DefaultTrackSelector())
        player!!.setVideoTextureView(textureView)
        player!!.addVideoListener(object : VideoListener {
            override fun onVideoSizeChanged(videoWidth: Int, videoHeight: Int, unappliedRotationDegrees: Int, pixelWidthHeightRatio: Float) {
                super.onVideoSizeChanged(videoWidth, videoHeight, unappliedRotationDegrees, pixelWidthHeightRatio)
                textureView.setTransform(prepareMatrix(textureView, videoWidth.toFloat(), videoHeight.toFloat(), FOCAL_POINT))
            }

            override fun onRenderedFirstFrame() {
                //                Log.d("AppLog", "onRenderedFirstFrame")
                player!!.removeVideoListener(this)
                imageView.animate().alpha(0f).setDuration(2000).start()
                //                imageView.visibility = View.INVISIBLE
            }
        })
        player!!.volume = 0f
        player!!.repeatMode = Player.REPEAT_MODE_ALL
        player!!.playRawVideo(this, VIDEO_RES_ID)
        player!!.playWhenReady = true
        //        player!!.playVideoFromUrl(this, "https://sample-videos.com/video123/mkv/240/big_buck_bunny_240p_20mb.mkv", cache!!)
        //        player!!.playVideoFromUrl(this, "https://sample-videos.com/video123/mkv/720/big_buck_bunny_720p_1mb.mkv", cache!!)
        //        player!!.playVideoFromUrl(this@MainActivity, "https://sample-videos.com/video123/mkv/720/big_buck_bunny_720p_1mb.mkv")
    }

    override fun onStart() {
        super.onStart()
        imageView.doOnPreDraw {
            val imageWidth: Float = imageView.drawable.intrinsicWidth.toFloat()
            val imageHeight: Float = imageView.drawable.intrinsicHeight.toFloat()
            imageView.imageMatrix = prepareMatrix(imageView, imageWidth, imageHeight, FOCAL_POINT)
        }
        playVideo()
    }

    override fun onStop() {
        super.onStop()
        if (player != null) {
            player!!.setVideoTextureView(null)
            //        playerView.player = null
            player!!.release()
            player = null
        }
    }

    override fun onDestroy() {
        super.onDestroy()
        if (!isChangingConfigurations)
            cache?.release()
    }

    fun SimpleExoPlayer.playRawVideo(context: Context, @RawRes rawVideoRes: Int) {
        val dataSpec = DataSpec(RawResourceDataSource.buildRawResourceUri(rawVideoRes))
        val rawResourceDataSource = RawResourceDataSource(context)
        rawResourceDataSource.open(dataSpec)
        val factory: DataSource.Factory = DataSource.Factory { rawResourceDataSource }
        prepare(LoopingMediaSource(ExtractorMediaSource.Factory(factory).createMediaSource(rawResourceDataSource.uri)))
    }

    fun SimpleExoPlayer.playVideoFromUrl(context: Context, url: String, cache: Cache? = null) = playVideoFromUri(context, Uri.parse(url), cache)

    fun SimpleExoPlayer.playVideoFile(context: Context, file: File) = playVideoFromUri(context, Uri.fromFile(file))

    fun SimpleExoPlayer.playVideoFromUri(context: Context, uri: Uri, cache: Cache? = null) {
        val factory = if (cache != null)
            CacheDataSourceFactory(cache, DefaultHttpDataSourceFactory(getUserAgent(context)))
        else
            DefaultDataSourceFactory(context, MainActivity.getUserAgent(context))
        val mediaSource = ExtractorMediaSource.Factory(factory).createMediaSource(uri)
        prepare(mediaSource)
    }
}
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如果需要,这里是ImageView的解决方案:

class ScaleCropImageView(context: Context, attrs: AttributeSet?) : AppCompatImageView(context, attrs) {
    var focalPoint = PointF(0.5f, 0.5f)
        set(value) {
            field = value
            updateMatrix()
        }
    private val viewWidth: Float
        get() = (width - paddingLeft - paddingRight).toFloat()

    private val viewHeight: Float
        get() = (height - paddingTop - paddingBottom).toFloat()

    init {
        scaleType = ScaleType.MATRIX
    }

    override fun onSizeChanged(w: Int, h: Int, oldw: Int, oldh: Int) {
        super.onSizeChanged(w, h, oldw, oldh)
        updateMatrix()
    }

    override fun setImageDrawable(drawable: Drawable?) {
        super.setImageDrawable(drawable)
        updateMatrix()
    }

    @Suppress("MemberVisibilityCanBePrivate")
    fun updateMatrix() {
        if (scaleType != ImageView.ScaleType.MATRIX)
            return
        val dr = drawable ?: return
        imageMatrix = prepareMatrix(
                viewWidth, viewHeight,
                dr.intrinsicWidth.toFloat(), dr.intrinsicHeight.toFloat(), focalPoint, Matrix()
        )
    }

    private fun prepareMatrix(
            viewWidth: Float, viewHeight: Float, mediaWidth: Float, mediaHeight: Float,
            focalPoint: PointF, matrix: Matrix
    ): Matrix? {
        if (viewWidth <= 0 || viewHeight <= 0)
            return null
        var scaleFactor = viewHeight / mediaHeight
        if (mediaWidth * scaleFactor >= viewWidth) {
            // Fit height
            matrix.postScale(scaleFactor, scaleFactor, -(mediaWidth * scaleFactor - viewWidth) * focalPoint.x / (1 - scaleFactor), 0f)
        } else {
            // Fit width
            scaleFactor = viewWidth / mediaWidth
            matrix.postScale(scaleFactor, scaleFactor, 0f, -(mediaHeight * scaleFactor - viewHeight) * focalPoint.y / (1 - scaleFactor))
        }
        return matrix
    }
}
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Che*_*amp 9

问题是如何操纵图像,ImageView.ScaleType.CENTER_CROP但是将焦点从中心移动到距离图像顶部20%的另一个位置.首先,让我们看一下CENTER_CROP:

从文档:

CENTER_CROP

均匀缩放图像(保持图像的纵横比),使图像的尺寸(宽度和高度)等于或大于视图的相应尺寸(减去填充).然后图像在视图中居中.从XML,使用以下语法:android:scaleType="centerCrop".

换句话说,缩放图像而不失真,使得图像的宽度或高度(或宽度和高度)都适合视图,以便视图完全被图像填充(无间隙).

另一种想到这一点的方法是将图像的中心"固定"到视图的中心.然后缩放图像以满足上述标准.

在下面的视频中,白线标出图像的中心; 红线标出视图的中心.比例类型是CENTER_CROP.注意图像的中心点和视图是如何重合的.当视图改变大小时,无论视图大小如何,这两个点都会继续重叠并始终显示在视图的中心.

在此输入图像描述

那么,在不同的位置(如距离顶部20%)具有类似中心作物的行为意味着什么？与中心裁剪一样,我们可以指定距离图像顶部20%的点和距离视图顶部20%的点将像50%点一样"固定"在中心裁剪中"固定".此点的水平位置保持在图像和视图的50%.现在可以缩放图像以满足中心裁剪的其他条件,其指定图像的宽度和/或高度将适合视图而没有间隙.(视图大小被理解为视图大小减去填充.)

这是20%作物行为的简短视频.在此视频中,白线显示图像的中间,红线显示视图中的固定点,显示在水平红线后面的蓝线表示距图像顶部20%.(演示项目在GitHub上.

在此输入图像描述

以下结果显示了提供的完整图像以及从静止图像过渡的方框中的视频..

在此输入图像描述

MainActivity.kt
prepareMatrix()是用于确定如何缩放/裁剪图像的方法.视频还有一些额外的工作要做,因为当视频TextureView分配给视频时,视频看起来适合作为缩放类型"FIT_XY" TextureView.由于此缩放,必须在prepareMatrix()调用视频之前恢复媒体大小

class MainActivity : AppCompatActivity() {
    private val imageResId = R.drawable.test
    private val videoResId = R.raw.test
    private var player: SimpleExoPlayer? = null
    private val mFocalPoint = PointF(0.5f, 0.2f)

    override fun onCreate(savedInstanceState: Bundle?) {
        window.setBackgroundDrawable(ColorDrawable(0xff000000.toInt()))
        super.onCreate(savedInstanceState)
        if (cache == null) {
            cache = SimpleCache(File(cacheDir, "media"), LeastRecentlyUsedCacheEvictor(MAX_PREVIEW_CACHE_SIZE_IN_BYTES))
        }
        setContentView(R.layout.activity_main)
        //        imageView.visibility = View.INVISIBLE
        imageView.setImageResource(imageResId)
        imageView.doOnPreDraw {
            imageView.scaleType = ImageView.ScaleType.MATRIX
            val imageWidth: Float = ContextCompat.getDrawable(this, imageResId)!!.intrinsicWidth.toFloat()
            val imageHeight: Float = ContextCompat.getDrawable(this, imageResId)!!.intrinsicHeight.toFloat()
            imageView.imageMatrix = prepareMatrix(imageView, imageWidth, imageHeight, mFocalPoint, Matrix())
            val b = BitmapFactory.decodeResource(resources, imageResId)
            val d = BitmapDrawable(resources, b.copy(Bitmap.Config.ARGB_8888, true))
            val c = Canvas(d.bitmap)
            val p = Paint()
            p.color = resources.getColor(android.R.color.holo_red_dark)
            p.style = Paint.Style.STROKE
            val strokeWidth = 10
            p.strokeWidth = strokeWidth.toFloat()
            // Horizontal line
            c.drawLine(0f, imageHeight * mFocalPoint.y, imageWidth, imageHeight * mFocalPoint.y, p)
            // Vertical line
            c.drawLine(imageWidth * mFocalPoint.x, 0f, imageWidth * mFocalPoint.x, imageHeight, p)
            // Line in horizontal and vertical center
            p.color = resources.getColor(android.R.color.white)
            c.drawLine(imageWidth / 2, 0f, imageWidth / 2, imageHeight, p)
            c.drawLine(0f, imageHeight / 2, imageWidth, imageHeight / 2, p)

            imageView.setImageBitmap(d.bitmap)
            imageViewFull.setImageBitmap(d.bitmap)
        }
    }

    fun startPlay(view: View) {
        playVideo()
    }

    private fun getViewWidth(view: View): Float {
        return (view.width - view.paddingStart - view.paddingEnd).toFloat()
    }

    private fun getViewHeight(view: View): Float {
        return (view.height - view.paddingTop - view.paddingBottom).toFloat()
    }

    private fun prepareMatrix(targetView: View, mediaWidth: Float, mediaHeight: Float,
                              focalPoint: PointF, matrix: Matrix): Matrix {
        if (targetView.visibility != View.VISIBLE) {
            return matrix
        }
        val viewHeight = getViewHeight(targetView)
        val viewWidth = getViewWidth(targetView)
        val scaleFactorY = viewHeight / mediaHeight
        val scaleFactor: Float
        val px: Float
        val py: Float
        if (mediaWidth * scaleFactorY >= viewWidth) {
            // Fit height
            scaleFactor = scaleFactorY
            px = -(mediaWidth * scaleFactor - viewWidth) * focalPoint.x / (1 - scaleFactor)
            py = 0f
        } else {
            // Fit width
            scaleFactor = viewWidth / mediaWidth
            px = 0f
            py = -(mediaHeight * scaleFactor - viewHeight) * focalPoint.y / (1 - scaleFactor)
        }
        matrix.postScale(scaleFactor, scaleFactor, px, py)
        return matrix
    }

    private fun playVideo() {
        player = ExoPlayerFactory.newSimpleInstance(this@MainActivity, DefaultTrackSelector())
        player!!.setVideoTextureView(textureView)
        player!!.addVideoListener(object : VideoListener {
            override fun onVideoSizeChanged(width: Int, height: Int, unappliedRotationDegrees: Int, pixelWidthHeightRatio: Float) {
                super.onVideoSizeChanged(width, height, unappliedRotationDegrees, pixelWidthHeightRatio)
                val matrix = Matrix()
                // Restore true media size for further manipulation.
                matrix.setScale(width / getViewWidth(textureView), height / getViewHeight(textureView))
                textureView.setTransform(prepareMatrix(textureView, width.toFloat(), height.toFloat(), mFocalPoint, matrix))
            }

            override fun onRenderedFirstFrame() {
                Log.d("AppLog", "onRenderedFirstFrame")
                player!!.removeVideoListener(this)
                imageView.animate().alpha(0f).setDuration(2000).start()
                imageView.visibility = View.INVISIBLE
            }
        })
        player!!.volume = 0f
        player!!.repeatMode = Player.REPEAT_MODE_ALL
        player!!.playRawVideo(this, videoResId)
        player!!.playWhenReady = true
        //        player!!.playVideoFromUrl(this, "https://sample-videos.com/video123/mkv/240/big_buck_bunny_240p_20mb.mkv", cache!!)
        //        player!!.playVideoFromUrl(this, "https://sample-videos.com/video123/mkv/720/big_buck_bunny_720p_1mb.mkv", cache!!)
        //        player!!.playVideoFromUrl(this@MainActivity, "https://sample-videos.com/video123/mkv/720/big_buck_bunny_720p_1mb.mkv")
    }

    override fun onStop() {
        super.onStop()
        if (player != null) {
            player!!.setVideoTextureView(null)
            //        playerView.player = null
            player!!.release()
            player = null
        }
    }

    companion object {
        const val MAX_PREVIEW_CACHE_SIZE_IN_BYTES = 20L * 1024L * 1024L
        var cache: com.google.android.exoplayer2.upstream.cache.Cache? = null

        @JvmStatic
        fun getUserAgent(context: Context): String {
            val packageManager = context.packageManager
            val info = packageManager.getPackageInfo(context.packageName, 0)
            val appName = info.applicationInfo.loadLabel(packageManager).toString()
            return Util.getUserAgent(context, appName)
        }
    }

    fun SimpleExoPlayer.playRawVideo(context: Context, @RawRes rawVideoRes: Int) {
        val dataSpec = DataSpec(RawResourceDataSource.buildRawResourceUri(rawVideoRes))
        val rawResourceDataSource = RawResourceDataSource(context)
        rawResourceDataSource.open(dataSpec)
        val factory: DataSource.Factory = DataSource.Factory { rawResourceDataSource }
        prepare(LoopingMediaSource(ExtractorMediaSource.Factory(factory).createMediaSource(rawResourceDataSource.uri)))
    }

    fun SimpleExoPlayer.playVideoFromUrl(context: Context, url: String, cache: Cache? = null) = playVideoFromUri(context, Uri.parse(url), cache)

    fun SimpleExoPlayer.playVideoFile(context: Context, file: File) = playVideoFromUri(context, Uri.fromFile(file))

    fun SimpleExoPlayer.playVideoFromUri(context: Context, uri: Uri, cache: Cache? = null) {
        val factory = if (cache != null)
            CacheDataSourceFactory(cache, DefaultHttpDataSourceFactory(getUserAgent(context)))
        else
            DefaultDataSourceFactory(context, MainActivity.getUserAgent(context))
        val mediaSource = ExtractorMediaSource.Factory(factory).createMediaSource(uri)
        prepare(mediaSource)
    }
}
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