将RawImage保存到文件

Question

因此，我设置了一个RawImage，它可以从VR耳机的通过摄像头捕捉图像。

现在图片已经正确显示了，我想保存它.

public class CameraCaptureBehaviour : MonoBehaviour
{
    private const string Tag = "[CAMERA_CAPTURE]";
    private const int CaptureFrequency = 500;
    [field:SerializeField] private RawImage CameraImage { get; set; }

    private int count = 0;

    private void Update()
    {
        if (++count % CaptureFrequency != 0) return;
        AndroidHelper.LogCat("Trying to get image", Tag);
        try
        {
            SaveImage();
        }
        catch (Exception e)
        {
            AndroidHelper.LogCat(e.Message, Tag);
        }
    }

    private void SaveImage()
    {
        var texture = CameraImage.texture;
        if (texture == null)
        {
            AndroidHelper.LogCat("No camera image found.", Tag);
            return;
        }

        var texture2d = (Texture2D) texture;
        var imageBytes = texture2d.EncodeToJPG();
        
        AndroidHelper.LogCat($"imageBytes is null: {imageBytes == null}", Tag);
        if (imageBytes == null) return;
        
        var filename = DateTime.Now.ToString("yyyyMMddHHmmssffff") + ".jpg";
        var filepath = Path.Combine(Application.persistentDataPath, filename);
        AndroidHelper.LogCat($"{imageBytes.Length} to {filepath}", Tag);
        try
        {
            File.WriteAllBytes(filepath, imageBytes);
            AndroidHelper.LogCat("SAVED", Tag);
        }
        catch (Exception e)
        {
            AndroidHelper.LogCat(e.Message, Tag);
        }
    }
}

这给了我

[CAMERA_CAPTURE] Trying to get image
[CAMERA_CAPTURE] imageBytes is null: False
[CAMERA_CAPTURE] 0 to /storage/emulated/0/Android/data/my.app/files/202203290841482532.png
[CAMERA_CAPTURE] SAVED

我不知道为什么图像应该是空的。

让我们试试将Color32数组转换为字节数组以通过网络发送建议的将Color32数组转换为字节数组以通过网络发送：

public class CameraCaptureBehaviour : MonoBehaviour
{
    private const string Tag = "[CAMERA_CAPTURE]";
    private const int CaptureFrequency = 500;
    [field:SerializeField] private RawImage CameraImage { get; set; }

    private int count = 0;

    private void Update()
    {
        if (++count % CaptureFrequency != 0) return;
        AndroidHelper.LogCat("Trying to get image", Tag);
        try
        {
            SaveImage();
        }
        catch (Exception e)
        {
            AndroidHelper.LogCat(e.Message, Tag);
        }
    }

    private void SaveImage()
    {
        var texture = CameraImage.texture;
        if (texture == null)
        {
            AndroidHelper.LogCat("No camera image found.", Tag);
            return;
        }

        var texture2d = (Texture2D) texture;

        var color32 = new Color32Array();
        color32.colors = texture2d.GetPixels32();
        var imageBytes = color32.byteArray;
        
        AndroidHelper.LogCat($"imageBytes is null: {imageBytes == null}", Tag);
        if (imageBytes == null) return;
        
        var filename = DateTime.Now.ToString("yyyyMMddHHmmssffff") + ".jpg";
        var filepath = Path.Combine(Application.persistentDataPath, filename);
        AndroidHelper.LogCat($"{imageBytes.Length} to {filepath}", Tag);
        try
        {
            File.WriteAllBytes(filepath, imageBytes);
            AndroidHelper.LogCat("SAVED", Tag);
        }
        catch (Exception e)
        {
            AndroidHelper.LogCat(e.Message, Tag);
        }
    }
}

[StructLayout(LayoutKind.Explicit)]
public struct Color32Array
{
    [FieldOffset(0)]
    public byte[] byteArray;

    [FieldOffset(0)]
    public Color32[] colors;
}

这给了我

[CAMERA_CAPTURE] Trying to get image
[CAMERA_CAPTURE] Texture '' is not configured correctly to allow GetPixels

我还发现了https://answers.unity.com/questions/1503328/save-rawimage-texture-to-file.html --就像所有听起来完全符合你需要但几年前被问到的问题一样--完全缺乏有用的信息。

我只想把我在护目镜里看到的这张该死的照片保存下来，那不会很困难吧？！

如果能提供一些帮助，我们将不胜感激。

如何保存RawImage

(注：texture.GetType().FullName给了我UnityEngine.Texture2D)

(注意:检索后我检查了纹理大小，它是600x600的，所以图片不只是0像素大)

Answer 1

将图像布利特到RenderTexture，然后使用它创建一个新的Texture2D

private static Texture2D GetReadableTexture2d(Texture texture)
{
    var tmp = RenderTexture.GetTemporary(
        texture.width,
        texture.height,
        0,
        RenderTextureFormat.Default,
        RenderTextureReadWrite.Linear
    );
    Graphics.Blit(texture, tmp);

    var previousRenderTexture = RenderTexture.active;
    RenderTexture.active = tmp;

    var texture2d = new Texture2D(texture.width, texture.height);
    texture2d.ReadPixels(new Rect(0, 0, texture.width, texture.height), 0, 0);
    texture2d.Apply();

    RenderTexture.active = previousRenderTexture;
    RenderTexture.ReleaseTemporary(tmp);
    return texture2d;
}

然后，生成的Texture2D可以是EncodeToPNGd并保存：

public void SaveImage()
{
    SaveImage(GetReadableTexture2d(CameraImage.texture));
}

private static void SaveImage(Texture2D texture)
{
    var imageBytes = texture.EncodeToPNG();

    if (imageBytes.Length == 0)
    {
        AndroidHelper.LogCat($"Trying to save empty picture. Abort.", Tag);
        return;
    }

    var filename = DateTime.Now.ToString("yyyyMMddHHmmssffff") + ".png";
    var filepath = Path.Combine(Application.persistentDataPath, filename);
    AndroidHelper.LogCat($"{imageBytes.Length} to {filepath}", Tag);
    try
    {
        File.WriteAllBytes(filepath, imageBytes);
        AndroidHelper.LogCat("SAVED", Tag);
    }
    catch (Exception e)
    {
        AndroidHelper.LogCat(e.Message, Tag);
    }
}

不确定是否有更简单的方法，但这似乎是可行的，至少。

Answer 2

你可以叫texture2d.EncodeToJPG到texture2D，你说得对。但是，您不能只是将任何纹理转换到texture2D中。嗯，你可以，但事情不一定会解决，因为你知道你自己；

要将RENDERtexture转换为Texture2D，可以执行以下操作：

RenderTexture.active = texture;
Texture2D texture2d = new Texture2D(texture.width, texture.height);
texture2d.ReadPixels(new Rect(0, 0, texture.width, texture.height),0, 0);
texture2d.Apply();
RenderTexture.active = null;

如果这不起作用，您可以尝试Graphics.CopyTexture()，如derHugo所指出的，也可以使用google将特定的纹理类型转换为Texture2D

Answer 3

我认为您不能简单地将RawImage.texture转换为Texture2D。试着把它复制成实际的样子。

var texture2d = new Texture2D(texture.width, texture.hight);
Graphics.CopyTexture(texture, texture2d);    

请参阅Graphics.CopyTexture