问题描述
我正在尝试使用JCodec在Java SE桌面应用程序内部将一系列图像转换成视频.我尝试的几种方法都导致Windows Media Player无法播放视频.
I'm trying to use JCodec to turn a series of images into a video inside of a Java SE desktop application. The few methods I've tried all resulted in a video that Windows Media Player could not play.
我不清楚这是编解码器问题(可疑)还是我没有正确创建视频.当我尝试在Windows Media Player中播放视频时，我得到:
It is unclear to me if this is a codec issue (doubtful) or if I'm not creating the video properly. When I try to play the video in Windows Media Player I get:
这是我最近一直在使用的拼凑在一起的示例.我真的不了解视频格式的内部原理，所以我什至不能完全确定其中一些代码在做什么.
Here is the cobbled together sample that I've been using most recently. I really don't understand the internals of the video format, so I'm not even entirely sure what some of the code is doing.
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.Arrays;
import javax.imageio.ImageIO;
import org.jcodec.codecs.h264.H264Encoder;
import org.jcodec.codecs.h264.H264Utils;
import org.jcodec.common.NIOUtils;
import org.jcodec.common.SeekableByteChannel;
import org.jcodec.common.model.ColorSpace;
import org.jcodec.common.model.Picture;
import org.jcodec.containers.mp4.Brand;
import org.jcodec.containers.mp4.MP4Packet;
import org.jcodec.containers.mp4.TrackType;
import org.jcodec.containers.mp4.muxer.FramesMP4MuxerTrack;
import org.jcodec.containers.mp4.muxer.MP4Muxer;
import org.jcodec.scale.AWTUtil;
import org.jcodec.scale.RgbToYuv420;
public class CreateVideo {
private SeekableByteChannel ch;
private Picture toEncode;
private RgbToYuv420 transform;
private H264Encoder encoder;
private ArrayList<ByteBuffer> spsList;
private ArrayList<ByteBuffer> ppsList;
private FramesMP4MuxerTrack outTrack;
private ByteBuffer _out;
private int frameNo;
private MP4Muxer muxer;
public CreateVideo(File out) throws IOException {
ch = NIOUtils.writableFileChannel(out);
// Transform to convert between RGB and YUV
transform = new RgbToYuv420(0, 0);
// Muxer that will store the encoded frames
muxer = new MP4Muxer(ch, Brand.MP4);
// Add video track to muxer
outTrack = muxer.addTrackForCompressed(TrackType.VIDEO, 25);
// Allocate a buffer big enough to hold output frames
_out = ByteBuffer.allocate(1920 * 1080 * 6);
// Create an instance of encoder
encoder = new H264Encoder();
// Encoder extra data ( SPS, PPS ) to be stored in a special place of
// MP4
spsList = new ArrayList<ByteBuffer>();
ppsList = new ArrayList<ByteBuffer>();
}
public void encodeImage(BufferedImage bi) throws IOException {
if (toEncode == null) {
toEncode = Picture.create(bi.getWidth(), bi.getHeight(), ColorSpace.YUV420);
}
// Perform conversion
for (int i = 0; i < 3; i++) {
Arrays.fill(toEncode.getData()[i], 0);
}
transform.transform(AWTUtil.fromBufferedImage(bi), toEncode);
// Encode image into H.264 frame, the result is stored in '_out' buffer
_out.clear();
ByteBuffer result = encoder.encodeFrame(_out, toEncode);
// Based on the frame above form correct MP4 packet
spsList.clear();
ppsList.clear();
H264Utils.encodeMOVPacket(result, spsList, ppsList);
// Add packet to video track
outTrack.addFrame(new MP4Packet(result, frameNo, 25, 1, frameNo, true, null, frameNo, 0));
frameNo++;
}
public void finish() throws IOException {
// Push saved SPS/PPS to a special storage in MP4
outTrack.addSampleEntry(H264Utils.createMOVSampleEntry(spsList, ppsList));
// Write MP4 header and finalize recording
muxer.writeHeader();
NIOUtils.closeQuietly(ch);
}
public static void main(String[] args) throws IOException {
CreateVideo encoder = new CreateVideo(new File("C:\\video\\video.mp4"));
for (int i = 10; i < 34; i++) {
String filename = String.format("C:\\video\\%02d.png", i);
BufferedImage bi = ImageIO.read(new File(filename));
encoder.encodeImage(bi);
}
encoder.finish();
}
}
如果有一些更简单的编解码器/容器，我就不受H264或MP4的束缚.唯一的要求是它应在没有安装其他软件的Windows 7基准框架上播放.
I'm not tied to H264 or MP4 if there is some easier codec/container. The only requirement is that it should play on a baseline Windows 7 box with no additional software installed.
推荐答案
我在使用jcodec的RgbToYuv420()转换时遇到很多问题.
我使用自己的函数将RGB BufferedImage转换为Yuv420.
我遇到的一个问题是RgbToYuv420对计算出的upix和vpix求平均值值，这导致我的mp4中的颜色全部变色了.
I had a lot of issues with jcodec's RgbToYuv420() transform.
I used my own function to transform my RGB BufferedImage to Yuv420.
One issue I had was that RgbToYuv420 averages the computed upix and vpixvalues, and it was causing the colors in my mp4 to be all wonky.
// make a YUV420J out of BufferedImage pixels
private Picture makeFrame(BufferedImage bi, ColorSpace cs)
{
DataBuffer imgdata = bi.getRaster().getDataBuffer();
int[] ypix = new int[imgdata.getSize()];
int[] upix = new int[ imgdata.getSize() >> 2 ];
int[] vpix = new int[ imgdata.getSize() >> 2 ];
int ipx = 0, uvoff = 0;
for (int h = 0; h < bi.getHeight(); h++) {
for (int w = 0; w < bi.getWidth(); w++) {
int elem = imgdata.getElem(ipx);
int r = 0x0ff & (elem >>> 16);
int g = 0x0ff & (elem >>> 8);
int b = 0x0ff & elem;
ypix[ipx] = ((66 * r + 129 * g + 25 * b) >> 8) + 16;
if ((0 != w % 2) && (0 != h % 2)) {
upix[uvoff] = (( -38 * r + -74 * g + 112 * b) >> 8) + 128;
vpix[uvoff] = (( 112 * r + -94 * g + -18 * b) >> 8) + 128;
uvoff++;
}
ipx++;
}
}
int[][] pix = { ypix, upix, vpix, null };
// old API
// return new Picture(bi.getWidth(), bi.getHeight(), pix, ColorSpace.YUV420J);
return Picture.createPicture(bi.getWidth(), bi.getHeight(), pix, ColorSpace.YUV420J);
}
这篇关于如何使用JCodec将一系列图像转换为视频?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！