Improve YUV data image received resolution on MSDK-v5.9

Hello everyone, a few months ago I asked you how to extract the bitmap from the image captured in real time from the drone using YUV data listener. Post: https://sdk-forum.dji.net/hc/en-us/community/posts/25059494247449-FPVWidget-get-Bitmap-in-MSDK-V5

It worked, I managed to extract it here and continued, however I would like to improve the quality of the extracted image, is this possible by code? If there is any way, could you show me a code example?

Images extracted from YUV data converted to bitmap and saved as JPG are approximately 700kb in size.

I would really need a way to improve the quality of these images to a higher resolution (HD, FullHD etc) so that I can pass the bitmap to an extractor of the QRCodes present in the image.

The drone: Mavic 3 Enterprise

Code to extract YUV Data:

fun getBitmap(callback: FPVWidgetBitmapCallback): Bitmap? {
    var bitmap: Bitmap? = null

    if (videoDecoderYuv == null) return null

    videoDecoderYuv!!.addYuvDataListener(object : YuvDataListener {
        override fun onReceive(
            mediaFormat: MediaFormat?,
            data: ByteArray?,
            width: Int,
            height: Int
        ) {
            // This value may be increased if the photos come in the wrong color
            if (++block == 10) {
                block = 0
                data?.let {
                    AsyncTask.execute {
                        val yuvImage = YuvImage(prepareYuvDataToJPEG420P(data, width, height),
                            ImageFormat.NV21, width, height, null)
                        val out = ByteArrayOutputStream()
                        yuvImage.compressToJpeg(Rect(0, 0, width, height), 100, out)
                        val imageBytes = out.toByteArray()
                        bitmap = BitmapFactory.decodeByteArray(imageBytes, 0, imageBytes.size)
                        callback.onReceive(bitmap)

                        out.close()
                    }
                }
                videoDecoderYuv!!.removeYuvDataListener(this)
            }
        }
    })

    return bitmap
}

private fun prepareYuvDataToJPEG420P(yuvFrame: ByteArray, width: Int, height: Int): ByteArray {
    if (yuvFrame.size < width * height) {
        return yuvFrame
    }
    val length = width * height
    val u = ByteArray(width * height / 4)
    val v = ByteArray(width * height / 4)
    for (i in u.indices) {
        u[i] = yuvFrame[length + i]
        v[i] = yuvFrame[length + u.size + i]
    }
    for (i in u.indices) {
        yuvFrame[length + 2 * i] = v[i]
        yuvFrame[length + 2 * i + 1] = u[i]
    }
    return yuvFrame
}

DJI Developer Support

September 29, 2024 07:54

Are you referring to the blurriness of the image after the YUV data has undergone processing? Regarding data processing, the MSDK only provides a reference method; other processing methods need to be implemented by you.

Xaooo

September 30, 2024 03:13

Them both, i want to know a way to improve quality of image converted and a possible way to get a image with a better resolution from YUV data (like HD, full HD or another better resolution)

October 07, 2024 11:59

Any updates?

October 08, 2024 09:24

Sorry, but we do not have any guidance documents regarding YUV data processing. If you are considering using other interfaces, you may refer to the methods mentioned in this issue to generate photo files; however, there are currently no reference methods for modifying the resolution. https://sdk-forum.dji.net/hc/zh-cn/community/posts/33709871608089

Improve YUV data image received resolution on MSDK-v5.9

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