使用内置的机器人类比其他 Java 库容易得多,并且应该可以满足您的需求。
如果您需要 >= 30fps(每秒超过 30 个屏幕截图)的流畅视频,您应该首先尝试使用机器人方法并使用其中的性能改进异步存储屏幕截图.
如果它不适合您,请尝试使用JNA也就是说(尽管它更复杂)几乎可以保证能够实现流畅的屏幕捕获。
与机器人的接触
机器人类确实能够做你想做的事情,大多数机器人屏幕捕获方法所面临的问题是saving的屏幕截图。一种方法可能如下所示:循环 captureScreen() 方法,将屏幕抓取到 BufferedImage 中,将其转换为字节数组,并在将图像的未来引用添加到目标文件后,使用异步文件写入器将其保存到目标文件中。 ArrayList能够在存储图像数据的同时继续进行。
// Pseudo code
while (capturing)
{
grab bufferedImage (screenCapture) from screen
convert bufferImage to byte array
start asynchronous file channel to write to the output file
and add the future reference (return value) to the ArrayList
}
与 JNA 的接触
原问题:Java中如何快速截图?
由于仅链接是不好的做法,因此我将在此处发布示例:
import java.awt.Rectangle;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.DataBuffer;
import java.awt.image.DataBufferInt;
import java.awt.image.DataBufferUShort;
import java.awt.image.DirectColorModel;
import java.awt.image.Raster;
import java.awt.image.WritableRaster;
import com.sun.jna.Native;
import com.sun.jna.platform.win32.W32API;
import com.sun.jna.win32.W32APIOptions;
public class JNAScreenShot
{
public static BufferedImage getScreenshot(Rectangle bounds)
{
W32API.HDC windowDC = GDI.GetDC(USER.GetDesktopWindow());
W32API.HBITMAP outputBitmap = GDI.CreateCompatibleBitmap(windowDC, bounds.width, bounds.height);
try
{
W32API.HDC blitDC = GDI.CreateCompatibleDC(windowDC);
try
{
W32API.HANDLE oldBitmap = GDI.SelectObject(blitDC, outputBitmap);
try
{
GDI.BitBlt(blitDC, 0, 0, bounds.width, bounds.height, windowDC, bounds.x, bounds.y, GDI32.SRCCOPY);
}
finally
{
GDI.SelectObject(blitDC, oldBitmap);
}
GDI32.BITMAPINFO bi = new GDI32.BITMAPINFO(40);
bi.bmiHeader.biSize = 40;
boolean ok = GDI.GetDIBits(blitDC, outputBitmap, 0, bounds.height, (byte[]) null, bi, GDI32.DIB_RGB_COLORS);
if (ok)
{
GDI32.BITMAPINFOHEADER bih = bi.bmiHeader;
bih.biHeight = -Math.abs(bih.biHeight);
bi.bmiHeader.biCompression = 0;
return bufferedImageFromBitmap(blitDC, outputBitmap, bi);
}
else
{
return null;
}
}
finally
{
GDI.DeleteObject(blitDC);
}
}
finally
{
GDI.DeleteObject(outputBitmap);
}
}
private static BufferedImage bufferedImageFromBitmap(GDI32.HDC blitDC, GDI32.HBITMAP outputBitmap, GDI32.BITMAPINFO bi)
{
GDI32.BITMAPINFOHEADER bih = bi.bmiHeader;
int height = Math.abs(bih.biHeight);
final ColorModel cm;
final DataBuffer buffer;
final WritableRaster raster;
int strideBits = (bih.biWidth * bih.biBitCount);
int strideBytesAligned = (((strideBits - 1) | 0x1F) + 1) >> 3;
final int strideElementsAligned;
switch (bih.biBitCount)
{
case 16:
strideElementsAligned = strideBytesAligned / 2;
cm = new DirectColorModel(16, 0x7C00, 0x3E0, 0x1F);
buffer = new DataBufferUShort(strideElementsAligned * height);
raster = Raster.createPackedRaster(buffer, bih.biWidth, height, strideElementsAligned, ((DirectColorModel) cm).getMasks(), null);
break;
case 32:
strideElementsAligned = strideBytesAligned / 4;
cm = new DirectColorModel(32, 0xFF0000, 0xFF00, 0xFF);
buffer = new DataBufferInt(strideElementsAligned * height);
raster = Raster.createPackedRaster(buffer, bih.biWidth, height, strideElementsAligned, ((DirectColorModel) cm).getMasks(), null);
break;
default:
throw new IllegalArgumentException("Unsupported bit count: " + bih.biBitCount);
}
final boolean ok;
switch (buffer.getDataType())
{
case DataBuffer.TYPE_INT:
{
int[] pixels = ((DataBufferInt) buffer).getData();
ok = GDI.GetDIBits(blitDC, outputBitmap, 0, raster.getHeight(), pixels, bi, 0);
}
break;
case DataBuffer.TYPE_USHORT:
{
short[] pixels = ((DataBufferUShort) buffer).getData();
ok = GDI.GetDIBits(blitDC, outputBitmap, 0, raster.getHeight(), pixels, bi, 0);
}
break;
default:
throw new AssertionError("Unexpected buffer element type: " + buffer.getDataType());
}
if (ok)
{
return new BufferedImage(cm, raster, false, null);
}
else
{
return null;
}
}
private static final User32 USER = User32.INSTANCE;
private static final GDI32 GDI = GDI32.INSTANCE;
}
interface GDI32 extends com.sun.jna.platform.win32.GDI32
{
GDI32 INSTANCE = (GDI32) Native.loadLibrary(GDI32.class);
boolean BitBlt(HDC hdcDest, int nXDest, int nYDest, int nWidth, int nHeight, HDC hdcSrc, int nXSrc, int nYSrc, int dwRop);
HDC GetDC(HWND hWnd);
boolean GetDIBits(HDC dc, HBITMAP bmp, int startScan, int scanLines, byte[] pixels, BITMAPINFO bi, int usage);
boolean GetDIBits(HDC dc, HBITMAP bmp, int startScan, int scanLines, short[] pixels, BITMAPINFO bi, int usage);
boolean GetDIBits(HDC dc, HBITMAP bmp, int startScan, int scanLines, int[] pixels, BITMAPINFO bi, int usage);
int SRCCOPY = 0xCC0020;
}
interface User32 extends com.sun.jna.platform.win32.User32
{
User32 INSTANCE = (User32) Native.loadLibrary(User32.class, W32APIOptions.UNICODE_OPTIONS);
HWND GetDesktopWindow();
}
更多信息和方法
使用 Java 和 awt.Robot 时提高屏幕捕获速度
http://www.dreamincode.net/forums/topic/234896-faster-screen-capture/
如何在屏幕捕获程序中使用 Java 获得超过 30FPS?
http://ffmpeg.org
See also
http://www.thepcwizard.in/2012/12/java-screen-capturing-tutorial.html
如何开发屏幕截图转视频应用
http://hiddensciencex.blogspot.co.at/2014/01/fast-screen-capture-in-java-example.html
http://www.coderanch.com/t/340180/GUI/java/efficient-screenshot-Java
http://www.javaworld.com/article/2071755/learn-java/capture-the-screen.html
ffmpeg 用于屏幕捕获?
Java 小程序屏幕截图到视频
使用 Java 进行 DirectX 程序的屏幕截图